assignment on fluid and electrolyte imbalance

Fluid and Electrolytes, Acid-Base Balance

Fluid and electrolyte balance is a dynamic process that is crucial for life and homeostasis.

Fluid occupies almost 60% of the weight of an adult.
Body fluid is located in two fluid compartments: the intracellular space and the extracellular space .
Electrolytes in body fluids are active chemicals or cations that carry positive charges and anions that carry negative charges.
The major cations in the body fluid are sodium, potassium , calcium, magnesium, and hydrogen ions.
The major anions are chloride, bicarbonate, sulfate, and proteinate ions.

Negative and positive feedback, location of fluids, fluid regulation mechanisms, normal intake and output, overhydration and edema, dehydration, electrolytes, permeability of membranes, passive transport, active transport, fluid and electrolyte balance, acid, bases, and salts, potential of hydrogen, classification, pathophysiology, clinical manifestations, complications, assessment and diagnostic findings, pharmacologic therapy, nursing assessment, nursing care planning & goals, nursing interventions, discharge and home care guidelines, documentation guidelines, practice quiz: fluids and electrolytes, homeostasis.

Homeostasis is the dynamic process in which the body maintains balance by constantly adjusting to internal and external stimuli.

Feedback is the relaying of information about a given condition to the appropriate organ or system.
Negative feedback. Negative feedback occurs when the body reverses an original stimulus for the body to regain physiologic balance.
Positive feedback. Positive feedback enhances or intensifies the original stimulus.
Examples. Blood pressure control and maintenance of normal body temperature are examples of negative feedback while blood clotting after an injury and a woman in labor are examples of positive feedback.

Systems Involved in Feedback

The major systems involved in feedback are the nervous and endocrine systems.

Nervous system. The nervous system regulates homeostasis by sensing system deviations and sending nerve impulses to appropriate organs.
Endocrine system. The endocrine system uses the release and action of hormones to maintain homeostasis.

Body Fluids

Fluids make up a large portion of the body, which is approximately 50%-60% of the total body weight.

Main compartments. Body fluids are divided into two main compartments: the intracellular fluid and the extracellular fluid compartments.
Intracellular fluid. Intracellular fluid functions as a stabilizing agent for the parts of the cell, helps maintain cell shape and assists with transport of nutrients across the cell membrane, in and out of the cell.
Extracellular fluid. Extracellular fluid mostly appears as interstitial tissue fluid and intravascular fluid.
The thirst center. The thirst center in the hypothalamus stimulates or inhibits the desire for a person to drink.
Antidiuretic hormone. ADH regulates the amount of water the kidney tubules absorb and is released in response to low blood volume or in response to an increase in the concentration of sodium and other solutes in the intravascular fluids.
The RAA system. The RAA system controls fluid volume, in which when the blood volume decreases, blood flow to the renal juxtaglomerular apparatus is reduced, thereby activating the RAA system.
Atrial natriuretic peptide. The heart also plays a role in correcting overload imbalances, by releasing ANP from the right atrium .
Daily intake. An adult human at rest takes appropriately 2,500 ml of fluid daily.
Levels of intake. Approximate levels of intake include fluids 1, 200 ml, foods 1, 000 ml, and metabolic products 30 ml.
Daily output. Daily output should be approximately equal in intake.
Normal output. Normal output occurs as urine, breathing, perspiration, feces , and in minimal amounts of vaginal secretions.
Overhydration. Overhydration is an excess of water in the body.
Edema. Edema is the excess accumulation of fluid in interstitial tissue spaces, also called third-space fluid.
Cause of edema. Edema is caused by a disruption of the filtration and osmotic forces of the body’s circulating fluids.
Treatment of edema. Diuretics are commonly given for systemic edema.
Dehydration. Dehydration is a deficiency of body water or excessive loss of water.
External causes. External causes of dehydration include prolonged sun exposure and excessive exercise, as well as diarrhea , vomiting, and burns .
Treatment of dehydration. Supplemental fluids and electrolytes are often administered.

An electrolyte is a substance that will disassociate into ions when dissolved in water.

Origins. Electrolytes are found in the form of inorganic salts, acids, and bases.
Active chemicals. Electrolyte concentrations are measured according to their chemical activity and expressed as milliequivalents.
Ions. Each chemical element has an electrical charge, either positive or negative.
Intracellular electrolytes. Important intracellular electrolytes are potassium, magnesium, sulfate, and phosphate, and the most dominant cation is potassium while the most dominant anion is phosphate.
Extracellular electrolytes. Important extracellular electrolytes include sodium, chlorine, calcium, and bicarbonate, and the most essential cation is sodium while chlorine is the most important anion.

Fluid and Electrolyte Transport

Total electrolyte concentration affects the body’s fluid balance .

The body cells. Nutrients and oxygen should enter body cells while waste products should exit the body.
The cell membrane. The cell membrane separates the intracellular environment from the extracellular environment.
Permeability. The ability of a membrane to allow molecules to pass through is known as permeability.
Freely permeable membranes. These membranes allow almost any food or waste substance to pass through.
Selectively permeable. The cell membrane is selectively permeable, meaning that each cell’s membrane allows only certain specific substances to pass through.
Passive transport. Passive transport mechanisms include diffusion, osmosis, and filtration.
Diffusion. Diffusion, or the process of “being widely spread” , is the random movement of molecules from an area of higher concentration to an area of lower concentration.
Osmosis. Osmosis is the diffusion of a pure solvent, such as water, across a semipermeable membrane in response to a concentration gradient in situations where the molecules of a higher concentration are non-diffusible.
Filtration. Filtration is the transport of water and dissolved materials concentration already exists in the cell.
Mechanisms. Active transport mechanisms require specific enzymes and energy expenditure in the form of adenosine triphosphate (ATP) .
Processes. Active transport processes can move solutes “uphill”, against the normal rules of concentration and pressure.

Fluid and electrolyte balance is vital for the proper functioning of all body systems.

Osmolarity. This is the property of particles in a solution to dissociate into ions.
Electroneutrality. This is the balance of positive and negative charges.

Acid-Base Balance

Acid-base balance is another important aspect of homeostasis.

Acid. An acid is one type of compound that contains the hydrogen ion.
Base. A base or alkali is a compound that contains the hydroxyl ion.
Salt. Salt is a combination of a base and an acid and is created when the positive ions of a base replace the positive hydrogen ions of an acid.
Important salts. The body contains several important salts like sodium chloride, potassium chloride, calcium chloride, calcium carbonate, calcium phosphate, and sodium phosphate.
pH. The symbol of pH refers to the potential or power of hydrogen ion concentration within the solution.
Low pH. If the pH number is lower than 7 , the solution is an acid .
High pH. If the pH is greater than 7 , a solution is basic or alkaline.
Neutral pH. If the pH is 7 , then the solution is neutral .
Changes. A change in the pH of a solution by one pH unit means a tenfold change in hydrogen concentration.
Buffers. A buffer is a chemical system set up to resist changes, particularly in hydrogen ion levels.
Bicarbonate buffer system. Sodium bicarbonate and carbonic acid are the body’s major chemical buffers.
Carbon dioxide. The major compound controlled by the lungs is CO2, and the respiratory system can very rapidly compensate for too much acid and too little acid by increasing or decreasing the respiratory rate, thereby altering the level of CO2.
Bicarbonate. Bicarbonate ions are basic components in the body, and the kidneys are key in regulating the amount of bicarbonate in the body.
Measurement of arterial blood gas. The pH level and amounts of specific gases in the blood indicate if there is more acid or base and their associated values.
Respiratory acidosis. Respiratory acidosis occurs when breathing is inadequate and PaCO2 builds up.
Respiratory alkalosis. Respiratory alkalosis occurs as a result of hyperventilation or excess aspirin intake.
Metabolic acidosis. In metabolic acidosis, metabolism is impaired, causing a decrease in bicarbonates and a buildup of lactic acid.
Metabolic alkalosis. Metabolic alkalosis occurs when bicarbonate ion concentration increases, causing an elevation in blood pH.

There are different fluid volume disturbances that may affect an individual.

Fluid volume deficit or hypovolemia occurs when the loss of ECF volume exceeds the intake of fluid.
Fluid volume excess or hypervolemia refers to an isotonic volume expansion of the ECF caused by the abnormal retention of water and sodium in approximately the same proportions in which they normally exist in the ECF.

Disturbances in electrolyte balances are common in clinical practice and must be corrected.

Hyponatremia refers to a serum sodium level that is less than 135 mEq/L
Hypernatremia is a serum sodium level higher than 145 mEq/L .
Hypokalemia usually indicates a deficit in total potassium stores.
Hyperkalemia refers to a potassium level greater than 5.0 mEq/L.
Hypocalcemia are serum levels below 8.6 mg/dl .
Hypercalcemia is calcium level greater than 10.2 mg/dl .
Hypomagnesemia refers to a below-normal serum magnesium concentration.
Hypermagnesemia are serum levels over 2.3 mg/dl .
Hypophosphatemia is indicated by a value below 2.5 mg/dl .
Hyperphosphatemia is a serum phosphorus level that exceeds 4.5 mg/dl in adults.

Nurses need an understanding of the pathophysiology of fluid and electrolyte balance to anticipate, identify, and respond to possible imbalances.

Concentrations. Electrolyte concentrations vary from those in the ICF to those in the ECF.
Sodium. Sodium ions outnumber any other cations in the ECF; therefore it is essential in the fluid regulation of the body.
Potassium. The ECF has a low concentration of potassium and can tolerate only small changes in its concentrations.
Maintenance. The body expends a great deal of energy in maintaining the sodium and potassium concentrations through cell membrane pumps that exchange sodium and potassium ions.
Osmosis. When two different solutions are separated by a membrane that is impermeable to the dissolved substances, fluid shifts from the region of low solute concentration to the high solute concentration until the solutions are of equal concentration.
Diffusion. Diffusion is the natural tendency of a substance to move from an area of higher concentration to an area of lower concentration.

Causes of fluid and electrolyte imbalances are discussed below in general.

Fluid retention. Retention of sodium is associated with fluid retention.
Loss of sodium. Excessive loss of sodium is associated with decreased volume of body fluid.
Trauma. Trauma causes release of intracellular potassium which is extremely dangerous.
Loss of body fluids. FVD results from loss of body fluids and occurs more rapidly when coupled with decreased fluid intake.
Fluid overload. Fluid volume excess may be related to a simple fluid overload or diminished function of the homeostatic mechanisms responsible for regulating fluid balance.
Low or high electrolyte intake. Diets low or excessive in electrolytes could also cause electrolyte imbalances.
Medications. There are certain medications that could lead to electrolyte imbalances when taken against the physician’s orders.

Signs and symptoms that occur in fluid and electrolyte imbalances are discussed below.

Fluid volume deficit. Clinical signs and symptoms include acute weight loss, decreased skin turgor, oliguria, concentrated urine, orthostatic hypotension , a weak, rapid heart rate , flattened neck veins, increased temperature, thirst, decreased or delayed capillary refill, cool, clammy skin, muscle weakness , and cramps.
Fluid volume excess. Clinical manifestations of FVE include edema, distended neck veins, and crackles.
Hyponatremia. Signs and symptoms include anorexia , nausea and vomiting, headache, lethargy, dizziness, confusion , muscle cramps and weakness , muscular twitching, seizures, dry skin, and edema.
Hypernatremia. The signs and symptoms are thirsts, elevated body temperature, hallucinations, lethargy, restlessness, pulmonary edema, twitching, increased BP, and pulse.
Hypokalemia. Clinical manifestations are fatigue, anorexia, muscle weakness, polyuria, decreased bowel motility, paresthesia, ileus, abdominal distention, and hypoactive reflexes
Hyperkalemia. Signs and symptoms include muscle weakness, tachycardia, paresthesia, dysrhythmias, intestinal colic , cramps, abdominal distention, and anxiety .
Hypocalcemia. The signs and symptoms are numbness, tingling of fingers, toes, and circumoral region, positive Trousseau’s sign and Chvostek’s sign, seizures, hyperactive deep tendon reflexes, irritability, and bronchospasm.
Hypercalcemia. The signs and symptoms include muscle weakness, constipation , anorexia, nausea and vomiting, dehydration, hypoactive deep tendon reflexes lethargy, calcium stones, flank pain , pathologic fractures, and deep bone pain.
Hypomagnesemia. Clinical manifestations include neuromuscular irritability, positive Trousseau’s and Chvostek’s sign, insomnia , mood changes, anorexia, vomiting, and increased deep tendon reflexes.
Hypermagnesemia. Signs and symptoms are flushing, hypotension , muscle weakness, drowsiness, hypoactive reflexes, depressed respirations, and diaphoresis.
Hypophosphatemia. Signs and symptoms include paresthesias, muscle weakness, bone pain and tenderness, chest pain , confusion , seizures, tissue hypoxia, and nystagmus.
Hyperphosphatemia. Clinical manifestations are tetany, tachycardia, anorexia, nausea and vomiting, muscle weakness, and hyperactive reflexes.

Fluid and electrolyte imbalances could result in complications if not treated promptly.

Dehydration. Fluid volume deficit could result in dehydration of the body tissues.
Cardiac overload. Fluid volume excess could result in cardiac overload if left untreated.
SIADH. Water is retained abnormally in SIADH.
Cardiac arrest. Too much potassium administered could lead to cardiac arrest.

The following are laboratory studies useful in diagnosing fluid and electrolyte imbalances:

BUN. BUN may be decreased in FVE due to plasma dilution.
Hematocrit. Hematocrit levels in FVD are greater than normal because there is a decreased plasma volume.
Physical examination. A physical exam is necessary to observe the signs and symptoms of the imbalances.
Serum electrolyte levels. Measurement of electrolyte levels should be performed to check for the presence of an imbalance.
ECG . ECG changes can also contribute to the diagnosis of fluid and electrolyte imbalance .
ABG analysis. ABG analysis may reveal acid-base imbalances.

Medical Management

Treatment of fluid and volume imbalances needs accuracy to avoid consequences that can result in complications.

Isotonic electrolyte solutions. These solutions are used to treat the hypotensive patient with FVD because they expand plasma volume.
Accurate I&O. Accurate and frequent assessments of I&O should be performed when therapy should be slowed or increased to prevent volume deficit or overload.
Dialysis. Hemodialysis or peritoneal dialysis is performed to remove nitrogenous wastes and control potassium and acid-base balance, and remove sodium and fluid.
Nutritional therapy. Treatment of fluid and electrolyte imbalances should involve restrictions or enforcement of the concerned electrolyte.
AVP receptor agonists. These are new pharmacologic agents that treat hyponatremia by stimulating free water excretion.
Diuretics. To decrease fluid volume in FVE, diuretics are administered.
IV calcium gluconate. If serum potassium levels are dangerously elevated, it may be necessary to administer IV calcium gluconate.
Calcitonin. Calcitonin can be used to lower the serum calcium level and is particularly useful for patients with heart disease or heart failure who cannot tolerate large sodium loads.

Nursing Management

Nurses may use effective teaching and communication skills to help prevent and treat various fluid and electrolyte disturbances.

Close monitoring should be done for patients with fluid and electrolyte imbalances.

I&O. The nurse should monitor for fluid I&O at least every 8 hours, or even hourly.
Daily weight. Assess the patient’s weight daily to measure any gains or losses.
Vital signs. Vital signs should be closely monitored.
Physical exam. A physical exam is needed to reinforce other data about a fluid or electrolyte imbalance.

The following diagnoses are found in patients with fluid and electrolyte imbalances.

Excess fluid volume related to excess fluid intake and sodium intake.
Deficient fluid volume related to active fluid loss or failure of regulatory mechanisms.
Imbalanced nutrition : less than body requirements related to inability to ingest food or absorb nutrients.
Imbalanced nutrition: more than body requirements related to excessive intake.
Diarrhea related to adverse effects of medications or malabsorption.

Main Article: 10 Fluid And Electrolyte Imbalances Nursing Care Plans

Planning and goals for fluid and electrolyte imbalances include:

Maintenance of fluid volume at a functional level.
Display of normal laboratory values .
Demonstration appropriate changes in lifestyle and behaviors including eating patterns and food quantity/quality.
Reestablishment and maintenance of normal pattern and GI functioning.

There are specific nursing interventions for fluid and electrolyte imbalances that can aid in alleviating the patient’s condition.

Monitor turgor. Skin and tongue turgor are indicators of the fluid status of the patient.
Urine concentration. Obtain urine sample of the patient to check for urine concentration.
Oral and parenteral fluids. Administer oral or parenteral fluids as indicated to correct the deficit.
Oral rehydration solutions. These solutions provide fluid, glucose , and electrolytes in concentrations that are easily absorbed.
Central nervous system changes. The nurse must be alert for central nervous system changes such as lethargy, seizures, confusion, and muscle twitching.
Diet. The nurse must encourage intake of electrolytes that are deficient or restrict intake if the electrolyte levels are excessive.

Evaluation of the care plan can check the effectiveness of the treatments. The interventions are deemed effective if the client has:

Maintained fluid volume at a functional level.
Displayed normal laboratory results.
Demonstrated appropriate changes in lifestyle and behaviors including eating patterns and food quantity/quality.
Reestablished and maintained normal pattern and GI functioning.

After hospitalization, treatment and maintenance of the condition must continue at home.

Diet. A diet rich in all the nutrients and electrolytes that a person needs should be enforced.
Fluid intake. Fluid intake must take shape according to the recommendations of the physician.
Follow-up. A week after discharge, the patient must return for a follow-up checkup for evaluation of electrolyte and fluid status.
Medications. Compliance with prescribed medications should be strict to avoid recurrence of the condition.

Data should be documented for future medical and legal references. The nurse must document:

Individual findings, including factors affecting ability to manage body fluids and degree of deficit.
I&O, fluid balance, changes in weight, urine specific gravity, and vital signs.
Results of diagnostic testing and laboratory studies.
Plan of care.
Client’s responses to treatment, teaching, and actions performed.
Attainment or progress toward desired outcome.
Modifications to plan of care.

Here’s a 10-item quiz about the study guide . Please visit our nursing test bank page for more NCLEX practice questions .

1. ECF is primarily composed of:

A. Aqueous fluid and lymphatic fluid. B. CSF and interstitial fluid. C. Interstitial and intravascular fluids. D. Vascular fluid and CSF.

2. A chemical set up to resist changes, particularly in the level of pH, is:

A. A base. B. A buffer. C. A salt. D. An acid.

3. Water moves across a semipermeable membrane via which process?

A. Active transport. B. Diffusion. C. Filtration. D. Osmosis.

4. To balance water output, an average adult must have daily fluid intake of approximately:

A. 500-900 ml. B. 1,000-2,000 ml. C. 2,000-3,000 ml. D. 4,000-6,000 ml.

5. The primary organs involved in pH regulation are:

A. Kidneys and lungs. B. Heart and intestines. C. Lung and endocrine glands. D. Skin and kidneys.

6. A clinical manifestation not found in hypokalemia is:

A. Muscle weakness B. Oliguria C. Postural hypotension D. Bradycardia

7. The nurse should expect that a patient with mild fluid volume excess would be prescribed a diuretic that blocks sodium reabsorption in the distal tubule, such as:

A. Bumex B. Demadex C. HydroDIURIL D. Lasix

8. Nursing intervention for a patient with a diagnosis of hyponatremia includes all of the following except:

A. Assessing for symptoms of nausea and malaise. B. Encouraging the intake of low-sodium liquids such as coffee or tea. C. Monitoring neurologic status D. Restricting tap water intake.

9. To supplement a diet with foods rich in potassium, the nurse should recommend the addition of:

A. Fruits such as bananas and apricots B. Green leafy vegetables C. Milk and yogurt D. Nuts and legumes

10. The most characteristic manifestation of hypocalcemia and hypomagnesemia is:

A. Anorexia and nausea. B. Constipation C. Lack of coordination D. Tetany

Answers and Rationale

1. Answer: C. Interstitial and intravascular fluids.

C: The extracellular fluid is primarily composed of interstitial and intravascular fluids.
A: Aqueous fluid and lymphatic fluid is not a part of the ECF.
B: CSF is not a part of ECF while interstitial fluid is.
D: Vascular fluid and CSF is not a part of the ECF.

2. Answer: B. A buffer.

B: A buffer is a chemical system set up to resist changes, particularly in hydrogen ion levels.
A: A base or alkali is a compound that contains the hydroxyl ion.
C: A salt is a combination of a base and an acid and is created when the positive ions of a base replace the positive hydrogen ions of an acid.
D: An acid is one type of compound that contains the hydrogen ion.

3. Answer: D. Osmosis.

D: Osmosis is the diffusion of a pure solvent, such as water, across a semipermeable membrane in response to a concentration gradient in situations where the molecules of a higher concentration are non diffusible.
A: Active transport mechanisms require specific enzymes and energy expenditure in the form of adenosine triphosphate (ATP).
B: Diffusion, or the process of “being widely spread”, is the random movement of molecules from an area of higher concentration to an area of lower concentration.
C: Filtration is the transport of water and dissolved materials concentration already exists in the cell.

4. Answer: C. 2,000-3,000 ml.

C: An adult human at rest takes appropriately 2, 500 ml of fluid daily.
A: 500-900 ml is inadequate fluid intake.
B: 1,000-2,000 ml is inadequate fluid intake.
D: 4,000-6,000 ml is inadequate fluid intake.

5. Answer: A. Kidneys and lungs.

A: The kidneys and lungs are the primary organs involved in pH regulation.
B: The heart and the intestines are not involved in pH regulation.
C: The lung and endocrine glands are not involved in pH regulation.
D: The skin and kidneys are not involved in pH regulation.

6. Answer: B. Oliguria

B: Polyuria is present in hypokalemia instead of oliguria.
A: Muscle weakness is a clinical manifestation of hypokalemia.
C: Postural hypotension a clinical manifestation of hypokalemia.
D: Bradycardia a clinical manifestation of hypokalemia

7. Answer: D. Lasix

D: Lasix is a diuretic commonly prescribed for patients with mild fluid volume excess.
A: Bumex is not recommended for patients with mild fluid volume excess.
B: Demadex is not recommended for patients with mild fluid volume excess.
C: HydroDIURIL is not the diuretic that blocks sodium reabsorption in the distal tubule.

8. Answer: B. Encouraging the intake of low-sodium liquids such as coffee or tea.

B: The nurse should encourage intake of high-sodium liquids to correct hyponatremia.
A: The nurse must assess for nausea and malaise because these are clinical manifestations of hyponatremia.
C: Neurologic status should be monitored to avoid neurologic complications.
D: Tap water intake should be restricted for patients with hyponatremia.

9. Answer: A. Fruits such as bananas and apricots

A: Bananas and apricots are rich in potassium.
B: Green leafy vegetables are rich in iron.
C: Milk and yogurt are rich in calcium.
D: Nuts and legumes are rich in protein.

10. Answer: D. Tetany

D: Decreased levels of calcium and magnesium leads to tetany.
A: Anorexia is a manifestation of hypomagnesemia while nausea is a sign of hypercalcemia .
B: Constipation is not a manifestation of hypocalcemia or hypomagnesemia.
C: Lack of coordination is not a manifestation of hypocalcemia or hypomagnesemia.

8-Step Guide to ABG Analysis: Tic-Tac-Toe Method
10 Fluid And Electrolyte Imbalances Nursing Care Plans
Homeostasis, Fluids and Electrolytes NCLEX Practice Quiz 1 (30 Items)
Homeostasis, Fluids and Electrolytes NCLEX Practice Quiz 2 (30 Items)
Homeostasis, Fluids and Electrolytes NCLEX Practice Quiz 3 (30 Items)

10 thoughts on “Fluid and Electrolytes, Acid-Base Balance”

This study guide helped in addition to my textbook!

thanks a ton!

I am reading game of thrones and the hate you give

I GAIN TOO MUCH KNOWLEDGE FROM YOUR NURSESLABS I AAM VERY THANKFUL TO YOU!

Hi Mam / Sir, You are very sweet and generous with your support. Thank you.

Thank you so much! This has been made so simple and easy to grasp. I love it!

Well doe, well structured and evidence based practice

but Lack of Nursing procedure

Hi Abusoff, Thanks so much for the high praise! 😊 Really glad to hear you found the content on fluid and electrolytes acid-base balance super helpful. If you’ve got more questions or if there’s another topic you’re keen on diving into, just give a shout. Always here to keep the good stuff coming!

Nursing Fundamentals [Internet].

About Open RN

Chapter 15 Fluids and Electrolytes

15.1. fluids and electrolytes introduction, learning objectives.

Describe variables that influence fluid and electrolyte balance
Identify factors related to fluid/electrolyte balance across the life span
Assess a patient’s nutritional and fluid/electrolyte status
Outline specific nursing interventions to promote fluid and electrolyte balance
Base decisions on the signs and symptoms of fluid volume excess and fluid volume deficit
Base decisions on the interpretation of diagnostic tests and lab values indicative of a disturbance in fluid and electrolyte balance
Identify evidence-based practices

The human body maintains a delicate balance of fluids and electrolytes to help ensure proper functioning and homeostasis. When fluids or electrolytes become imbalanced, individuals are at risk for organ system dysfunction. If an imbalance goes undetected and is left untreated, organ systems cannot function properly and ultimately death will occur. Nurses must be able to recognize subtle changes in fluid or electrolyte balances in their patients so they can intervene promptly. Timely assessment and intervention prevent complications and save lives.

15.2. BASIC FLUID AND ELECTROLYTE CONCEPTS

Before learning about how to care for patients with fluid and electrolyte imbalances, it is important to understand the physiological processes of the body’s regulatory mechanisms. The body is in a constant state of change as fluids and electrolytes are shifted in and out of cells within the body in an attempt to maintain a nearly perfect balance. A slight change in either direction can have significant consequences on various body systems.

Body Fluids

Body fluids consist of water, electrolytes, blood plasma and component cells, proteins, and other soluble particles called solutes. Body fluids are found in two main areas of the body called intracellular and extracellular compartments. See Figure 15.1 [ 1 ] for an illustration of intracellular and extracellular compartments.

Figure 15.1

Intracellular and Extracellular Compartments

Intracellular fluids (ICF) are found inside cells and are made up of protein, water, electrolytes, and solutes. The most abundant electrolyte in intracellular fluid is potassium. Intracellular fluids are crucial to the body’s functioning. In fact, intracellular fluid accounts for 60% of the volume of body fluids and 40% of a person’s total body weight! [ 2 ]

Extracellular fluids (ECF) are fluids found outside of cells. The most abundant electrolyte in extracellular fluid is sodium. The body regulates sodium levels to control the movement of water into and out of the extracellular space due to osmosis.

Extracellular fluids can be further broken down into various types. The first type is known as intravascular fluid that is found in the vascular system that consists of arteries, veins, and capillary networks. Intravascular fluid is whole blood volume and also includes red blood cells, white blood cells, plasma, and platelets. Intravascular fluid is the most important component of the body’s overall fluid balance.

Loss of intravascular fluids causes the nursing diagnosis Deficient Fluid Volume , also referred to as hypovolemia . Intravascular fluid loss can be caused by several factors, such as excessive diuretic use, severe bleeding, vomiting, diarrhea, and inadequate oral fluid intake. If intravascular fluid loss is severe, the body cannot maintain adequate blood pressure and perfusion of vital organs. This can result in hypovolemic shock and cellular death when critical organs do not receive an oxygen-rich blood supply needed to perform cellular function.

A second type of extracellular fluid is interstitial fluid that refers to fluid outside of blood vessels and between the cells. For example, if you have ever cared for a patient with heart failure and noticed increased swelling in the feet and ankles, you have seen an example of excess interstitial fluid referred to as edema .

The remaining extracellular fluid, also called transcellular fluid , refers to fluid in areas such as cerebrospinal, synovial, intrapleural, and gastrointestinal system. [ 3 ]

Fluid Movement

Fluid movement occurs inside the body due to osmotic pressure, hydrostatic pressure, and osmosis. Proper fluid movement depends on intact and properly functioning vascular tissue lining, normal levels of protein content within the blood, and adequate hydrostatic pressures inside the blood vessels. Intact vascular tissue lining prevents fluid from leaking out of the blood vessels. Protein content of the blood (in the form of albumin) causes oncotic pressure that holds water inside the vascular compartment. For example, patients with decreased protein levels (i.e., low serum albumin) experience edema due to the leakage of intravascular fluid into interstitial areas because of decreased oncotic pressure.

Hydrostatic pressure is defined as pressure that a contained fluid exerts on what is confining it. In the intravascular fluid compartment, hydrostatic pressure is the pressure exerted by blood against the capillaries. Hydrostatic pressure opposes oncotic pressure at the arterial end of capillaries, where it pushes fluid and solutes out into the interstitial compartment. On the venous end of the capillary, hydrostatic pressure is reduced, which allows oncotic pressure to pull fluids and solutes back into the capillary. [ 4 ] , [ 5 ] See Figure 15.2 [ 6 ] for an illustration of hydrostatic pressure and oncotic pressure in a capillary.

Figure 15.2

Hydrostatic Pressure

Filtration occurs when hydrostatic pressure pushes fluids and solutes through a permeable membrane so they can be excreted. An example of this process is fluid and waste filtration through the glomerular capillaries in the kidneys. This filtration process within the kidneys allows excess fluid and waste products to be excreted from the body in the form of urine.

Fluid movement is also controlled through osmosis. Osmosis is water movement through a semipermeable membrane, from an area of lesser solute concentration to an area of greater solute concentration, in an attempt to equalize the solute concentrations on either side of the membrane. Only fluids and some particles dissolved in the fluid are able to pass through a semipermeable membrane; larger particles are blocked from getting through. Because osmosis causes fluid to travel due to a concentration gradient and no energy is expended during the process, it is referred to as passive transport . [ 7 ] See Figure 15.3 [ 8 ] for an illustration of osmosis where water has moved to the right side of the membrane to equalize the concentration of solutes on that side with the left side.

Figure 15.3

Osmosis causes fluid movement between the intravascular, interstitial, and intracellular fluid compartments based on solute concentration. For example, recall a time when you have eaten a large amount of salty foods. The sodium concentration of the blood becomes elevated. Due to the elevated solute concentration within the bloodstream, osmosis causes fluid to be pulled into the intravascular compartment from the interstitial and intracellular compartments to try to equalize the solute concentration. As fluid leaves the cells, they shrink in size. The shrinkage of cells is what causes many symptoms of dehydration, such as dry, sticky mucous membranes. Because the brain cells are especially susceptible to fluid movement due to osmosis, a headache may occur if adequate fluid intake does not occur.

Solute Movement

Solute movement is controlled by diffusion, active transport, and filtration. Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration to equalize the concentration of solutes throughout an area. (Note that diffusion is different from osmosis because osmosis is the movement of fluid whereas diffusion is the movement of solutes.) See Figure 15.4 [ 9 ] for an image of diffusion. Because diffusion travels down a concentration gradient, the solutes move freely without energy expenditure. An example of diffusion is the movement of inhaled oxygen molecules from alveoli to the capillaries in the lungs so that they can be distributed throughout the body.

Figure 15.4

Active transport , unlike diffusion, involves moving solutes and ions across a cell membrane from an area of lower concentration to an area of higher concentration. Because active transport moves solutes against a concentration gradient to prevent an overaccumulation of solutes in an area, energy is required for this process to take place. [ 10 ] An example of active transport is the sodium-potassium pump, which uses energy to maintain higher levels of sodium in the extracellular fluid and higher levels of potassium in the intracellular fluid. See Figure 15.5 [ 11 ] for an image of diffusion and the sodium-potassium pump regulating sodium and potassium levels in the extracellular and intracellular compartments. Recall that sodium (Na+) is the primary electrolyte in the extracellular space and potassium (K+) is the primary electrolyte in the intracellular space.

Figure 15.5

Sodium-Potassium Pump

Fluid and Electrolyte Regulation

The body must carefully regulate intravascular fluid accumulation and excretion to prevent fluid volume excesses or deficits and maintain adequate blood pressure. Water balance is regulated by several mechanisms including ADH, thirst, and the Renin-Angiotensin-Aldosterone System (RAAS).

Fluid intake is regulated by thirst. As fluid is lost and the sodium level increases in the intravascular space, serum osmolality increases. Serum osmolality is a measure of the concentration of dissolved solutes in the blood. Osmoreceptors in the hypothalamus sense increased serum osmolarity levels and trigger the release of ADH (antidiuretic hormone) in the kidneys to retain fluid. The osmoreceptors also produce the feeling of thirst to stimulate increased fluid intake. However, individuals must be able to mentally and physically respond to thirst signals to increase their oral intake. They must be alert, fluids must be accessible, and the person must be strong enough to reach for fluids. When a person is unable to respond to thirst signals, dehydration occurs. Older individuals are at increased risk of dehydration due to age-related impairment in thirst perception. The average adult intake of fluids is about 2,500 mL per day from both food and drink. An increased amount of fluids is needed if the patient has other medical conditions causing excessive fluid loss, such as sweating, fever, vomiting, diarrhea, and bleeding.

The Renin-Angiotensin-Aldosterone System (RAAS) plays an important role in regulating fluid output and blood pressure. See Figure 15.6 [ 12 ] for an illustration of the Renin-Angiotensin-Aldosterone System (RAAS). When there is decreased blood pressure (which can be caused by fluid loss), specialized kidney cells make and secrete renin into the bloodstream. Renin acts on angiotensinogen released by the liver and converts it to angiotensin I, which is then converted to angiotensin II. Angiotensin II does a few important things. First, angiotensin II causes vasoconstriction to increase blood flow to vital organs. It also stimulates the adrenal cortex to release aldosterone. Aldosterone is a steroid hormone that triggers increased sodium reabsorption by the kidneys and subsequent increased serum osmolality in the bloodstream. As you recall, increased serum osmolality causes osmosis to move fluid into the intravascular compartment in an effort to equalize solute particles. The increased fluids in the intravascular compartment increase circulating blood volume and help raise the person’s blood pressure. An easy way to remember this physiological process is “aldosterone saves salt” and “water follows salt.” [ 13 ]

Figure 15.6

Renin Angiotensin Aldosterone System (RAAS)

Fluid output occurs mostly through the kidneys in the form of urine. Fluid is also lost through the skin as perspiration, through the gastrointestinal tract in the form of stool, and through the lungs during respiration. Forty percent of daily fluid output occurs due to these “insensible losses” through the skin, gastrointestinal tract, and lungs and cannot be measured. The remaining 60% of daily fluid output is in the form of urine. Normally, the kidneys produce about 1,500 mL of urine per day when fluid intake is adequate. Decreased urine production is an early sign of dehydration or kidney dysfunction. It is important for nurses to assess urine output in patients at risk. If a patient demonstrates less than 30 mL/hour (or 0.5 mL/kg/hour) of urine output over eight hours, the provider should be notified for prompt intervention. See Figure 15.7 [ 14 ] for an illustration of an average adult’s daily water balance of 2,500 mL fluid intake balanced with 2,500 mL fluid output.

Figure 15.7

Water Balance

Fluid Imbalance

Two types of fluid imbalances are excessive fluid volume (also referred to as hypervolemia) and deficient fluid volume (also referred to as hypovolemia). These imbalances primarily refer to imbalances in the extracellular compartment, but can cause fluid movement in the intracellular compartments based on the sodium level of the blood.

Excessive Fluid Volume

Excessive fluid volume (also referred to as hypervolemia) occurs when there is increased fluid retained in the intravascular compartment. Patients at risk for developing excessive fluid volume are those with the following conditions:

Heart Failure
Kidney Failure
Pregnancy [ 15 ]

Symptoms of fluid overload include pitting edema, ascites, and dyspnea and crackles from fluid in the lungs. Edema is swelling in dependent tissues due to fluid accumulation in the interstitial spaces. Ascites is fluid retained in the abdomen.

Treatment depends on the cause of the fluid retention. Sodium and fluids are typically restricted and diuretics are often prescribed to eliminate the excess fluid. For more information about the nursing care of patients with excessive fluid volume, see the “ Applying the Nursing Process ” section.

Deficient Fluid Volume

Deficient fluid volume (also referred to as hypovolemia or dehydration) occurs when loss of fluid is greater than fluid input. Common causes of deficient fluid volume are diarrhea, vomiting, excessive sweating, fever, and poor oral fluid intake. Individuals who have a higher risk of dehydration include the following:

Older adults
Infants and children
Patients with chronic diseases such as diabetes mellitus and kidney disease
Patients taking diuretics and other medications that cause increased urine output
Individuals who exercise or work outdoors in hot weather [ 16 ]

In adults, symptoms of dehydration are as follows:

Feeling very thirsty
Urinating and sweating less than usual
Dark, concentrated urine
Feeling tired
Changes in mental status
Dizziness due to decreased blood pressure
Elevated heart rate [ 17 ]

In infants and young children, additional symptoms of dehydration include the following:

Crying without tears
No wet diapers for three hours or more
Being unusually sleepy or drowsy
Irritability
Eyes that look sunken
Sunken fontanel [ 18 ]

Dehydration can be mild and treated with increased oral intake such as water or sports drinks. Severe cases can be life-threatening and require the administration of intravenous fluids.

For more information about water balance and fluid movement, review the following video.

Video Review of Fluid and Electrolytes [ 19 ]

15.3. intravenous solutions.

When patients experience deficient fluid volume, intravenous (IV) fluids are often prescribed. IV fluid restores fluid to the intravascular compartment, and some IV fluids are also used to facilitate the movement of fluid between compartments due to osmosis. There are three types of IV fluids: isotonic, hypotonic, and hypertonic.

Isotonic Solutions

Isotonic solutions are IV fluids that have a similar concentration of dissolved particles as blood. An example of an isotonic IV solution is 0.9% Normal Saline (0.9% NaCl). Because the concentration of the IV fluid is similar to the blood, the fluid stays in the intravascular space and osmosis does not cause fluid movement between compartments. See Figure 15.8 [ 1 ] for an illustration of isotonic IV solution administration with no osmotic movement of fluid with cells. Isotonic solutions are used for patients with fluid volume deficit (also called hypovolemia) to raise their blood pressure. However, infusion of too much isotonic fluid can cause excessive fluid volume (also referred to as hypervolemia).

Figure 15.8

Lack of Fluid Movement When Isotonic IV Solution Is Administered

Hypotonic Solutions

Hypotonic solutions have a lower concentration of dissolved solutes than blood. An example of a hypotonic IV solution is 0.45% Normal Saline (0.45% NaCl). When hypotonic IV solutions are infused, it results in a decreased concentration of dissolved solutes in the blood as compared to the intracellular space. This imbalance causes osmotic movement of water from the intravascular compartment into the intracellular space. For this reason, hypotonic fluids are used to treat cellular dehydration. See Figure 15.9 [ 2 ] for an illustration of the osmotic movement of fluid into a cell when a hypotonic IV solution is administered, causing lower concentration of solutes (pink molecules) in the bloodstream compared to within the cell.

Figure 15.9

Hypotonic IV Solution Causing Osmotic Movement of Fluid Into Cell

However, if too much fluid moves out of the intravascular compartment into cells, cerebral edema can occur. It is also possible to cause worsening hypovolemia and hypotension if too much fluid moves out of the intravascular space and into the cells. Therefore, patient status should be monitored carefully when hypotonic solutions are infused.

Hypertonic Solutions

Hypertonic solutions have a higher concentration of dissolved particles than blood. An example of hypertonic IV solution is 3% Normal Saline (3% NaCl). When infused, hypertonic fluids cause an increased concentration of dissolved solutes in the intravascular space compared to the cells. This causes the osmotic movement of water out of the cells and into the intravascular space to dilute the solutes in the blood. See Figure 15.10 [ 3 ] for an illustration of osmotic movement of fluid out of a cell when hypertonic IV fluid is administered due to a higher concentration of solutes (pink molecules) in the bloodstream compared to the cell.

Figure 15.10

Hypertonic IV Solution Causing Osmotic Fluid Movement Out of a Cell

When administering hypertonic fluids, it is essential to monitor for signs of hypervolemia such as breathing difficulties and elevated blood pressure. Additionally, if hypertonic solutions with sodium are given, the patient’s serum sodium level should be closely monitored. [ 4 ] See Table 15.3 for a comparison of types of IV solutions, their uses, and nursing considerations.

Comparison of IV Solutions [ 6 ]

See Figure 15.11 [ 5 ] for an illustration comparing how different types of IV solutions affect red blood cell size.

Figure 15.11

Comparison of Osmotic Effects of Hypertonic, Isotonic, and Hypotonic IV Fluids on Red Blood Cells

Osmolarity is defined as the proportion of dissolved particles in an amount of fluid and is generally the term used to describe body fluids. As the dissolved particles become more concentrated, the osmolarity increases. Osmolality refers to the proportion of dissolved particles in a specific weight of fluid. The terms osmolarity and osmolality are often used interchangeably in clinical practice.

15.4. electrolytes.

Electrolytes play an important role in bodily functions and fluid regulation. There is a very narrow target range for normal electrolyte values, and slight abnormalities can have devastating consequences. For this reason, it is crucial to understand normal electrolyte ranges, causes of electrolyte imbalances, signs and symptoms of imbalances, and appropriate treatments.

Sodium levels in the blood typically range from 136-145 mEq/L. [ 1 ] Refer to each agency’s normal reference range on the lab report. Sodium is the most abundant electrolyte in the extracellular fluid (ECF) and is maintained by the sodium-potassium pump. Sodium plays an important role in maintaining adequate fluid balance in the intravascular and interstitial spaces. See the “ Fluid and Electrolyte Regulation ” section of this chapter for more information about how the body regulates sodium and water balance.

Hypernatremia refers to an elevated sodium level in the blood. Typically, hypernatremia is caused by excess water loss due to lack of fluid intake, vomiting, or diarrhea. As you recall, elevated sodium levels in the blood cause the osmotic movement of water out of the cells to dilute the blood. This causes the body’s cells to shrink, referred to as cellular dehydration. This fluid shift can have a significant impact on various organs within the body and is especially notable in the patient’s neurological function. As fluid shifts out of the brain cells, the nurse may notice symptoms such as confusion, irritability, lethargy, and even seizures. Other signs and symptoms of hypernatremia include severe thirst and sticky mucous membranes. See Figure 15.12 [ 2 ] for an illustration of a patient with severe thirst due to hypernatremia. Treatment for hypernatremia includes decreasing sodium intake, increasing oral water intake, and rehydrating with a hypotonic IV solution. [ 3 ] , [ 4 ]

Figure 15.12

Hypernatremia

Hyponatremia refers to a decreased sodium level in the blood. Hyponatremia can be caused by excess water intake or excessive administration of hypotonic IV solutions. For example, a marathon runner who only rehydrates with water (without other fluids with solutes like Gatorade) can develop hyponatremia. As with hypernatremia, altered sodium levels often cause neurological symptoms due to the movement of water into brain cells, causing them to swell. Symptoms of hyponatremia are headache, confusion, seizures, and coma. Treatment for hyponatremia depends on the cause and often consists of limiting water intake or discontinuing administration of hypotonic IV fluids. If hyponatremia is severe, a hypertonic IV saline solution may be prescribed to gradually raise the patient’s sodium level. [ 5 ]

Video Review of Fluids and Electrolytes: Sodium [ 6 ]

Potassium levels normally range from 3.5 to 5.1 mEq/L. [ 7 ] Refer to each agency’s normal reference range on the lab report. Potassium is the most abundant electrolyte in intracellular fluid and is maintained inside the cell by the sodium-potassium pump. Potassium is regulated by aldosterone in the kidneys and is obtained in the diet through consumption of foods such as bananas, oranges, and tomatoes. See Figure 15.13 [ 8 ] for an illustration of potassium regulation by aldosterone. Recall that aldosterone causes reabsorption of sodium and excretion of potassium in the distal tubule of the kidneys. In response to potassium levels rising or sodium levels falling in the bloodstream, the adrenal cortex releases aldosterone and targets the kidneys. In response, the kidneys excrete potassium and reabsorb sodium. Potassium is also impacted by the hormone insulin that moves potassium into the cells from the ECF. [ 9 ]

Figure 15.13

Potassium Regulation by Aldosterone

Potassium is necessary for normal cardiac function, neural function, and muscle contractility, including effective contractility of the cardiac muscles. Abnormal potassium levels can cause significantly abnormal heart rhythms and contractility. Potassium is poorly conserved by the body and much is lost with urine output. For this reason, it is often necessary to provide potassium supplements when administering loop and thiazide diuretics because potassium is excreted from the kidneys along with water. [ 10 ] Potassium supplementation can be given orally or by IV infusion mixed with fluids. Potassium must NEVER be administered IV push because it can immediately stop the heart.

Hyperkalemia refers to increased potassium levels in the blood. Hyperkalemia can be caused by kidney failure, metabolic acidosis, and administration of potassium-sparing diuretics or oral/intravenous potassium supplements. Signs and symptoms of hyperkalemia are generally cardiac in nature and include irritability, cramping, diarrhea, and electrocardiogram (ECG) abnormalities. As hyperkalemia worsens, ECG abnormalities may progress to cardiac dysrhythmias and cardiac arrest.

Treatment for hyperkalemia depends on the severity of the hyperkalemia symptoms. For mild symptoms, decreased potassium intake in the diet is helpful. Adjustment to medications contributing to increased levels of potassium may be indicated. For severe symptoms, administration of sodium polystyrene sulfonate (Kayexalate) orally or rectally helps bind excess potassium so it is excreted through the GI tract. Insulin may be administered to push potassium into cells and decrease serum potassium levels. When administering an insulin infusion, it is important to monitor blood glucose levels closely, often hourly per agency policy. The patient often requires supplemental IV dextrose to prevent low blood sugar levels when insulin is used for potassium reduction. IV calcium gluconate may also be given to prevent excess potassium from affecting cardiac muscle. This is a temporary measure and wears off quickly but allows time for other treatments to take effect and lower potassium levels before cardiac arrest develops. For severe symptomatic hyperkalemia, temporary hemodialysis may also be used to quickly decrease potassium levels. [ 11 ]

Hypokalemia refers to decreased potassium level in the blood. Hypokalemia can be caused by excessive vomiting, diarrhea, potassium-wasting diuretics, and insulin use, as well as lack of potassium in the diet. Signs and symptoms of hypokalemia include weakness, arrhythmias, lethargy, and a thready pulse. View helpful mnemonics for hypokalemia using the following hyperlink. Treatment for hypokalemia includes increasing oral intake of potassium in the diet and oral or IV potassium in fluids supplementation. It is important to remember that administering IV potassium too quickly can cause cardiac arrest. In fact, potassium is one of the ingredients used during lethal injection to stop the heart.

View helpful mnemonics for hypokalemia at Hypokalemia NCLEX Review Notes.

Video review about potassium [ 12 ].

Calcium levels normally range from 8.6-10.2 mg/dL. [ 13 ] Refer to each agency’s normal reference range on the lab report. Calcium circulates in the bloodstream, but the majority is stored in bones. Calcium is important for bone and teeth structure, nerve transmission, and muscle contraction. Calcium excretion and reabsorption are regulated by the parathyroid hormone (PTH) that is secreted from the parathyroid glands near the thyroid. See Figure 15.14 [ 14 ] for an illustration of the parathyroid glands. As PTH is secreted in response to low calcium levels in the blood, calcium is reabsorbed in both the kidneys and the intestine and released from the bones to increase serum calcium levels. Calcium is also affected by dietary intake and physical activity. Activity causes calcium to move into bones whereas immobility causes the release of calcium from bones, which cases them to become weak. Dietary sources of calcium include dairy products, green leafy vegetables, sardines, and whole grains. [ 15 ]

Figure 15.14

Parathyroid Glands

Hypercalcemia refers to an increased calcium level. It can be caused by prolonged immobilization that allows calcium to leach out of the bones and into the serum. Additionally, there are many types of cancers that may cause excessive calcium release from bones. Hypercalcemia can also be caused by hyperparathyroidism and parathyroid tumors, which can cause too much PTH secretion, causing too much calcium to be reabsorbed in the kidneys and intestines and released from bone.

Signs and symptoms of hypercalcemia often impact the gastrointestinal and musculoskeletal systems. These symptoms include nausea, vomiting, constipation, increased thirst and/or urination, and skeletal muscle weakness. Treatment for hypercalcemia includes decreasing calcium intake in the diet, phosphate supplementation (which has an inverse relationship to calcium), hemodialysis, surgical removal of the parathyroid gland (if hyperparathyroidism is causing the hypercalcemia), and weight-bearing exercises as tolerated. [ 16 ]

Hypocalcemia refers to a decreased calcium level in the blood. Hypocalcemia can be caused by hypoparathyroidism where not enough PTH is excreted, causing a decreased reabsorption of calcium and decreased release of calcium from the bones. Hypocalcemia is also caused by vitamin D deficiency and renal disease. Because phosphorus is inversely related to calcium, an abnormally high phosphorus level as seen with renal failure can also result in hypocalcemia.

Signs and symptoms of hypocalcemia often impact the musculoskeletal and nervous systems. These include paresthesias (numbness and tingling) of the lips, tongue, hands and feet, muscle cramps, and tetany. Chvostek’s sign is a classic sign of acute hypocalcemia and is an involuntary twitching of facial muscles when the facial nerve is tapped. A second classic sign of acute hypocalcemia is Trousseau’s sign where a hand spasm is caused by inflating a blood pressure cuff to a level above systolic pressure for 3 minutes. See a video of a patient experiencing Chvostek’s and Trousseau’s signs in the hyperlink below. Treatment of hypocalcemia includes increasing oral intake of dietary calcium and vitamin D and oral or IV calcium supplementation and decreasing the phosphorus level if it is elevated. [ 17 ]

View a video of a patient exhibiting Chvostek’s Sign and Trousseau’s Signs of hypocalcemia.

Phosphorus levels typically range from 2.5-4.0 mg/dL. Refer to each agency’s normal reference range on the lab report. Phosphorus is stored in the bones and is predominantly found in the ICF with small amounts in the ECF. Phosphorus is important in energy metabolism, RNA and DNA formation, nerve function, muscle contraction, and for bone, teeth, and membrane building and repair. Phosphorus is excreted by the kidneys and absorbed by the intestines. Dietary phosphorus sources include dairy products, fruits, vegetables, meat, and cereal. [ 18 ]

Hyperphosphatemia refers to an increased phosphorus level in the blood and can be caused by kidney disease, crush injuries, or overuse of phosphate-containing enemas. Hyperphosphatemia itself is usually asymptomatic, but signs of associated hypocalcemia may be present due to the inverse relationship between phosphorus and calcium. Treatment for hyperphosphatemia includes decreasing intake of phosphorus, administration of phosphate-binder medications to help with excretion, and hemodialysis. [ 19 ]

Hypophosphatemia is a decreased phosphorus level in the blood. Acute hypophosphatemia can be caused by acute alcohol abuse, burns, diuretic use, respiratory alkalosis, resolving diabetic ketoacidosis, and starvation. Chronic hypophosphatemia is caused by hyperparathyroidism, vitamin D deficiency, prolonged use of phosphate binders, and hypomagnesemia or hypokalemia. Hypophosphatemia is usually asymptomatic, but in severe cases, it can cause muscle weakness, anorexia, encephalopathy, seizures, and death. Treatment for hypophosphatemia includes treating what is causing the imbalance, oral or IV phosphorus replacement, and increased phosphate-containing foods in the diet. [ 20 ]

Magnesium levels typically range from 1.5-2.4 mEq/L. Refer to each agency’s reference range on the lab report. Magnesium is essential for normal cardiac, nerve, muscle, and immune system functioning. About half of the body’s magnesium is stored in the bones. About 1% is stored in ECF and the rest is found in ICF. [ 21 ] Dietary sources of magnesium include green leafy vegetables, citrus, peanut butter, almonds, legumes, and chocolate.

Hypermagnesemia refers to an elevated magnesium level in the blood. It is usually the result of renal failure, excess magnesium replacement, or use of magnesium containing laxatives or antacids. Signs and symptoms of hypermagnesemia include bradycardia, weak and thready pulse, lethargy, tremors, hyporeflexia, muscle weakness, and cardiac arrest. Treatment for hypermagnesemia involves increasing fluid intake, discontinuing magnesium-containing medications, and in severe cases, hemodialysis or peritoneal dialysis. Additionally, administration of calcium gluconate can be helpful to reduce the cardiac effects of hypermagnesemia until the magnesium level can be lowered. [ 22 ]

Hypomagnesemia refers to decreased magnesium level in the blood. It typically results from inadequate magnesium in the diet, or from loop diuretics that excrete magnesium. Patients with alcohol use disorder often have hypomagnesemia due to concurrent poor diet and impaired nutrient absorption that occurs with alcohol consumption. Chronic proton pump inhibitor use can also cause hypomagnesemia due to impaired nutrient absorption.

Signs and symptoms of hypomagnesemia include nausea, vomiting, lethargy, weakness, leg cramps, tremor, dysrhythmias, and tetany that is associated with concurrent hypocalcemia that can occur with hypomagnesemia. Treatment for hypomagnesemia consists of increasing dietary intake of magnesium containing foods and oral or IV magnesium supplementation. [ 23 ]

See Table 15.4 for a comparison of causes, symptoms, and treatments of different electrolyte imbalances. As always, refer to agency lab reference ranges when providing patient care.

Comparison of Causes, Symptoms, and Treatments of Imbalanced Electrolyte Levels

15.5. ACID-BASE BALANCE

As with electrolytes, correct balance of acids and bases in the body is essential to proper body functioning. Even a slight variance outside of normal can be life-threatening, so it is important to understand normal acid-base values, as well their causes and how to correct them. The kidneys and lungs work together to correct slight imbalances as they occur. As a result, the kidneys compensate for shortcomings of the lungs, and the lungs compensate for shortcomings of the kidneys.

Arterial Blood Gases

Arterial blood gases (ABG) are measured by collecting blood from an artery, rather than a vein, and are most commonly collected via the radial artery. ABGs measure the pH level of the blood, the partial pressure of arterial oxygen (PaO2), the partial pressure of arterial carbon dioxide (PaCO2), the bicarbonate level (HCO3), and the oxygen saturation level (SaO2).

Prior to collecting blood gases, it is important to ensure the patient has appropriate arterial blood flow to the hand. This is done by performing the Allen test. When performing the Allen test, pressure is held on both the radial and ulnar artery below the wrist. Pressure is released from the ulnar artery to check if blood flow is adequate. If arterial blood flow is adequate, warmth and color should return to the hand.

pH is a scale from 0-14 used to determine the acidity or alkalinity of a substance. A neutral pH is 7, which is the same pH as water. Normally, the blood has a pH between 7.35 and 7.45. A blood pH of less than 7.35 is considered acidic, and a blood pH of more than 7.45 is considered alkaline.

The pH of blood is a measure of hydrogen ion concentration. A low pH, less than 7.35, occurs in acidosis when the blood has a high hydrogen ion concentration. A high pH, greater than 7.45, occurs in alkalosis when the blood has a low hydrogen ion concentration. Hydrogen ions are by-products of the metabolism of substances such as proteins, fats, and carbohydrates. These by-products create extra hydrogen ions (H+) in the blood that need to be balanced and kept within normal range as described earlier.

The body has several mechanisms for maintaining blood pH. The lungs are essential for maintaining pH and the kidneys also play a role. For example, when the pH is too low (i.e., during acidosis), the respiratory rate quickly increases to eliminate acid in the form of carbon dioxide (CO2). The kidneys excrete additional hydrogen ions (acid) in the urine and retain bicarbonate (base). Conversely, when the pH is too high (i.e., during alkalosis), the respiratory rate decreases to retain acid in the form of CO2. The kidneys excrete bicarbonate (base) in the urine and retain hydrogen ions (acid).

PaCO2 is the partial pressure of arterial carbon dioxide in the blood. The normal PaCO2 level is 35-45 mmHg. CO2 forms an acid in the blood that is regulated by the lungs by changing the rate or depth of respirations.

As the respiratory rate increases or becomes deeper, additional CO2 is removed causing decreased acid (H+) levels in the blood and increased pH (so the blood becomes more alkaline). As the respiratory rate decreases or becomes more shallow, less CO2 is removed causing increased acid (H+) levels in the blood and decreased pH (so the blood becomes more acidic).

Generally, the lungs work quickly to regulate the PaCO2 levels and cause a quick change in the pH. Therefore, an acid-base problem caused by hypoventilation can be quickly corrected by increasing ventilation, and a problem caused by hyperventilation can be quickly corrected by decreasing ventilation. For example, if an anxious patient is hyperventilating, they may be asked to breathe into a paper bag to rebreathe some of the CO2 they are blowing off. Conversely, a postoperative patient who is experiencing hypoventilation due to the sedative effects of receiving morphine is asked to cough and deep breathe to blow off more CO2.

HCO3 is the bicarbonate level of the blood and the normal range is 22-26. HCO3 is a base managed by the kidneys and helps to make the blood more alkaline. The kidneys take longer than the lungs to adjust the acidity or alkalinity of the blood, and the response is not visible upon assessment. As the kidneys sense an alteration in pH, they begin to retain or excrete HCO3, depending on what is needed. If the pH becomes acidic, the kidneys retain HCO3 to increase the amount of bases present in the blood to increase the pH. Conversely, if the pH becomes alkalotic, the kidneys excrete more HCO3, causing the pH to decrease.

PaO2 is the partial pressure of arterial oxygen in the blood. It more accurately measures a patient’s oxygenation status than SaO2 (the measurement of hemoglobin saturation with oxygen). Therefore, ABG results are also used to manage patients in respiratory distress.

Table 15.5a

ABG Components, Descriptions, Adult Normal Values, and Critical Values [ 2 ]

Video Review of Acid-Base Balance [ 3 ]

Interpreting Arterial Blood Gases

After the ABG results are received, it is important to understand how to interpret them. A variety of respiratory, metabolic, electrolyte, or circulatory problems can cause acid-base imbalances. Correct interpretation also helps the nurse and other health care providers determine the appropriate treatment and evaluate the effectiveness of interventions.

Arterial blood gasses can be interpreted as one of four conditions: respiratory acidosis, respiratory alkalosis, metabolic acidosis, or metabolic alkalosis. Once this interpretation is made, conditions can further be classified as compensated, partially compensated, or uncompensated. A simple way to remember how to interpret ABGs is by using the ROME method of interpretation, which stands for R espiratory O pposite, M etabolic E qual. This means that the respiratory component (PaCO2) moves in the opposite direction of the pH if the respiratory system is causing the imbalance. If the metabolic system is causing the imbalance, the metabolic component (HCO3) moves in the same direction as the pH. Some nurses find the Tic-Tac-Toe method of interpretation helpful. If you would like to learn more about this method, click on the hyperlink below to view a video.

Review of Tic-Tac-Toe Method of ABG Interpretation [ 4 ]

Respiratory Acidosis

Respiratory acidosis develops when carbon dioxide (CO2) builds up in the body (referred to as hypercapnia ), causing the blood to become increasingly acidic. Respiratory acidosis is identified when reviewing ABGs and the pH level is below 7.35 and the PaCO2 level is above 45, indicating the cause of the acidosis is respiratory. Note that in respiratory acidosis, as the PaCO2 level increases, the pH level decreases. Respiratory acidosis is typically caused by a medical condition that decreases the exchange of oxygen and carbon dioxide at the alveolar level, such as an acute asthma exacerbation, chronic obstructive pulmonary disease (COPD), or an acute heart failure exacerbation causing pulmonary edema. It can also be caused by decreased ventilation from anesthesia, alcohol, or administration of medications such as opioids and sedatives.

Chronic respiratory diseases, such as COPD, often cause chronic respiratory acidosis that is fully compensated by the kidneys retaining HCO3. Because the carbon dioxide levels build up over time, the body adapts to elevated PaCO2 levels so they are better tolerated. However, in acute respiratory acidosis, the body has not had time to adapt to elevated carbon dioxide levels, causing mental status changes associated with hypercapnia. Acute respiratory acidosis is caused by acute respiratory conditions, such as an asthma attack or heart failure exacerbation with pulmonary edema when the lungs suddenly are not able to ventilate adequately. As breathing slows and respirations become shallow, less CO2 is excreted by the lungs and PaCO2 levels quickly rise.

Signs of symptoms of hypercapnia vary depending upon the level and rate of CO2 accumulation in arterial blood:

Patients with mild to moderate hypercapnia may be anxious and/or complain of mild dyspnea, daytime sluggishness, headaches, or hypersomnolence.
Patients with higher levels of CO2 or rapidly developing hypercapnia develop delirium, paranoia, depression, and confusion that can progress to seizures and coma as levels continue to rise.

Individuals with normal lung function typically exhibit a depressed level of consciousness when the PaCO2 is greater than 75 to 80 mmHg, whereas patients with chronic hypercapnia may not develop symptoms until the PaCO2 rises above 90 to 100 mmHg. [ 5 ]

When a patient demonstrates signs of potential hypercapnia, the nurse should assess airway, breathing, and circulation. Urgent assistance should be sought, especially if the patient is in respiratory distress. The provider will order an ABG and prescribe treatments based on assessment findings and potential causes. Treatment for respiratory acidosis typically involves improving ventilation and respiration by removing airway restrictions, reversing oversedation, administering nebulizer treatments, or increasing the rate and depth of respiration by using a BiPAP or CPAP devices. BiPAP and CPAP devices provide noninvasive positive pressure ventilation to increase the depth of respirations, remove carbon dioxide, and oxygenate the patient. If these noninvasive interventions are not successful, the patient is intubated and placed on mechanical ventilation. [ 6 ] , [ 7 ]

Breathing Retraining

While sitting or lying supine, the patient should place one hand on their abdomen and the other on the chest, and then be asked to observe which hand moves with greater excursion. In hyperventilating patients, this will almost always be the hand on the chest. Ask the patient to adjust their breathing so that the hand on the abdomen moves with greater excursion and the hand on the chest barely moves at all. Assure the patient that this is hard to learn and will take some practice to fully master. Ask the patient to breathe in slowly over four seconds, pause for a few seconds, and then breathe out over a period of eight seconds. After 5 to 10 such breathing cycles, the patient should begin to feel a sense of calmness with a reduction in anxiety and an improvement in hyperventilation. Symptoms should ideally resolve with continuation of this breathing exercise.

If the breathing retraining technique is not successful in resolving a hyperventilation episode and severe symptoms persist, the patient may be prescribed a small dose of a short-acting benzodiazepine (e.g., lorazepam 0.5 to 1 mg orally or 0.5 to 1 mg intravenously). Current research indicates that instructing patients who are hyperventilating to rebreathe carbon dioxide (CO2) by breathing into a paper bag can cause significant hypoxemia with significant complications, so this intervention is no longer recommended. If rebreathing is used, oxygen saturation levels should be continuously monitored. [ 9 ]

Metabolic Acidosis

Metabolic acidosis occurs when there is an accumulation of acids (hydrogen ions) and not enough bases (HCO3) in the body. Under normal conditions, the kidneys work to excrete acids through urine and neutralize excess acids by increasing bicarbonate (HCO3) reabsorption from the urine to maintain a normal pH. When the kidneys are not able to perform this buffering function to the level required to excrete and neutralize the excess acid, metabolic acidosis results.

Metabolic acidosis is characterized by a pH level below 7.35 and an HCO3 level below 22 when reviewing ABGs. It is important to notice that both the pH and HCO3 decrease with metabolic acidosis (i.e., the pH and HCO3 move in the same downward direction). A common cause of metabolic acidosis is diabetic ketoacidosis, where acids called ketones build up in the blood when blood sugar is extremely elevated. Another common cause of metabolic acidosis in hospitalized patients is lactic acidosis, which can be caused by impaired tissue oxygenation. Metabolic acidosis can also be caused by increased loss of bicarbonate due to severe diarrhea or from renal disease that causes decreased acid elimination. Additionally, toxins such as salicylate excess can cause metabolic acidosis. [ 10 ]

Nurses may first suspect that a patient has metabolic acidosis due to rapid breathing that occurs as the lungs try to remove excess CO2 in an attempt to resolve the acidosis. Other symptoms of metabolic acidosis include confusion, decreased level of consciousness, hypotension, and electrolyte disturbances that can progress to circulatory collapse and death if not treated promptly. It is important to quickly notify the provider of suspected metabolic acidosis so that an ABG can be drawn and treatment prescribed (based on the cause of the metabolic acidosis) to allow acid levels to improve. Treatment includes IV fluids to improve hydration status, glucose management, and circulatory support. When pH drops below 7.1, IV sodium bicarbonate is often prescribed to help neutralize the acids in the blood. [ 11 ] , [ 12 ]

Metabolic Alkalosis

Metabolic alkalosis occurs when there is too much bicarbonate (HCO3) in the body or an excessive loss of acid (H+ ions). Metabolic alkalosis is defined by a pH above 7.45 and an HCO3 level above 26 on ABG results. Note that both pH and HCO3 are elevated in metabolic alkalosis.

Metabolic alkalosis can be caused by gastrointestinal loss of hydrogen ions, excessive urine loss, excessive levels of bicarbonate, or a shift of hydrogen ions from the bloodstream into cells.

Prolonged vomiting or nasogastric suctioning can also cause metabolic alkalosis. Gastric secretions have high levels of hydrogen ions (H+), so as acid is lost, the pH level of the bloodstream increases.

Excessive urinary loss (due to diuretics or excessive mineralocorticoids) can cause metabolic alkalosis due to loss of hydrogen ions in the urine. Intravenous administration of sodium bicarbonate can also cause metabolic alkalosis due to increased levels of bases introduced into the body. Although it was once thought that excessive intake of calcium antacids could cause metabolic alkalosis, it has been found that this only occurs if they are administered concurrently with Kayexelate. [ 13 ]

Hydrogen ions may shift into cells due to hypokalemia, causing metabolic alkalosis. When hypokalemia occurs (i.e., low levels of potassium in the bloodstream), potassium shifts out of cells and into the bloodstream in an attempt to maintain a normal level of serum potassium for optimal cardiac function. However, as the potassium (K+) molecules move out of the cells, hydrogen (H+) ions then move into the cells from the bloodstream to maintain electrical neutrality. This transfer of ions causes the pH in the bloodstream to drop, causing metabolic alkalosis. [ 14 ]

A nurse may first suspect that a patient has metabolic alkalosis due to a decreased respiratory rate (as the lungs try to retain additional CO2 to increase the acidity of the blood and resolve the alkalosis). The patient may also be confused due to the altered pH level. The nurse should report signs of suspected metabolic alkalosis because uncorrected metabolic alkalosis can result in hypotension and cardiac dysfunction. [ 15 ]

Treatment is prescribed based on the ABG results and the suspected cause. For example, treat the cause of the vomiting, stop the gastrointestinal suctioning, or stop the administration of diuretics. If hypokalemia is present, it should be treated. If bicarbonate is being administered, it should be stopped. Patients with kidney disease may require dialysis. [ 16 ]

Analyzing ABG Results

Now that we’ve discussed the differences between the various acid-base imbalances, let’s review the steps to systematically interpret ABG results. Table 15.5b outlines the steps of ABG interpretation.

Table 15.5b

Analyzing ABG Results [ 17 ] , [ 18 ]

Mitchel, J. H., Wildenthal, K., & Johnson Jr., R. L. (1972). The effects of acid-base disturbances on cardiovascular and pulmonary function. Kidney International, 1 , 375-389. https://www .kidney-international .org/article /S0085-2538(15)31047-4/pdf ↵

WakeMed Pathology Laboratories. (2016). Critical values . https://www .wakemed.org /assets/documents /pathology/lab-critical-values.pdf ↵

RegisteredNurseRN. (2015, May 6). ABGs made easy for nurses w/ tic tac toe method for arterial blood gas interpretation . [Video]. YouTube. All rights reserved. Video used with permission. https://youtu .be/URCS4t9aM5o ↵

Feller-Kopman, D. J., & Schwartzstein, R. M. (2020). The evaluation, diagnosis, and treatment of the adult patient with acute hypercapnic respiratory failure. UpToDate . https://www .uptodate .com/contents/the-evaluation-diagnosis-and-treatment-of-the-adult-patient-with-acute-hypercapnic-respiratory-failure ↵

A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Respiratory acidosis; [updated 2021, February 8]. https://medlineplus .gov /ency/article/000092.htm ↵

Schwartzstein, R. M., Richards, J., Edlow, J. A., & Roy-Byrne, P. P. (2020). Hyperventilation syndrome in adults. UpToDate . https://www .uptodate .com/contents/hyperventilation-syndrome-in-adults ↵

Emmett, M., & Szerlip, H. (2020). Approach to the adult with metabolic acidosis. UpToDate . https://www .uptodate .com/contents/approach-to-the-adult-with-metabolic-acidosis ↵

A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Metabolic acidosis; [updated 2021, February 8]. https://medlineplus .gov /ency/article/000335.htm ↵

Emmett, M., & Szerlip, H. (2020). Causes of metabolic alkalosis. UpToDate . https://www .uptodate .com/contents/causes-of-metabolic-alkalosis ↵

This work is a derivative of StatPearls by Brinkman and Sharma and is licensed under CC BY 4.0 ↵

This work is a derivative of StatPearls by Castro and Keenaghan and is licensed under CC BY 4.0 ↵

Woodruff, D. W. (2012). 6 easy steps to ABG analysis . Ed4Nurses, Inc. http://www .profcaseyscudmorern .org/uploads /4/5/0/4/45049193/abgebook.pdf ↵

15.6. APPLYING THE NURSING PROCESS

The nursing process is used continuously when caring for individuals who have fluid, electrolyte, or acid-base imbalances, or at risk for developing them, because their condition can change rapidly. This systematic approach to nursing care ensures that subtle cues or changes are not overlooked and that appropriate outcomes and interventions are implemented according to the patient’s current condition.

A thorough assessment provides valuable information about a patient’s current fluid, electrolyte, and acid-base balance, as well as risk factors for developing imbalances. Performing a chart review or focused health history is a good place to start collecting data, with any identified gaps or discrepancies verified during the physical assessment. It is also important to consider pertinent life span or cultural considerations that impact a patient’s fluid and electrolyte status.

Subjective Assessment

Subjective assessment data is information obtained from the patient as a primary source or family members or friends as a secondary source. This information must be obtained by interviewing the patient or someone accompanying the patient. Some of this information can be obtained through a chart review, but should be verified with the patient or family member for accuracy.

Subjective data to obtain includes age; history of chronic disease, surgeries, or traumas; dietary intake; activity level; prescribed medications and compliance with taking medications; pain; and bowel and bladder functioning. Subjective assessment data is helpful to determine normal pattern identification and risk identification. For example, a history of kidney disease or heart failure places the patient at risk for fluid volume excess, whereas diuretic use places the patient at risk for fluid volume deficit and electrolyte and acid-base imbalances. A history of diabetes mellitus also places a patient at risk for fluid, electrolyte, and acid-base imbalances. Recognizing these risks helps nurses be prepared for complications that may arise and allows the nurse to recognize subtle cues as problems develop.

Objective Assessment

Objective assessment data is information that the nurse directly observes. This data is obtained through a physical examination using inspection, auscultation, and palpation. A complete head-to-toe assessment should be performed to avoid missing clues to the patient’s condition.

Focused assessments such as trends in weight, 24-hour intake and output, vital signs, pulses, lung sounds, skin, and mental status are used to determine fluid balance, electrolyte, and acid-base status.

Accurate daily weights can provide important clues to fluid balance. Weights must be taken on the same scale, at the same time of day, with the patient wearing similar clothing in order to be accurate. A one kilogram change in weight in 24 hours is considered significant because this represents a one liter fluid gain or loss and should be reported to the provider.
Accurate measurement of 24-hour intake and output helps validate weight findings. Averaged urine output of less than 30 mL/hour or 0.5mL/hr/kg of concentrated urine should be reported to the provider.
Vital signs should be analyzed. An elevated blood pressure and bounding pulses are often seen with fluid volume excess. Decreased blood pressure with an elevated heart rate and a weak or thready pulse are hallmark signs of fluid volume deficit. Systolic blood pressure less than 100 mm Hg in adults, unless other parameters are provided, should be reported to the health care provider.
Lung crackles can signify fluid volume excess and are often first auscultated in the lower posterior lung fields.
Tight, edematous, shiny skin indicates fluid volume excess. See Figure 15.15 [ 1 ] for an image of edema. Conversely, skin tenting, dry mucous membranes, or dry skin indicate fluid volume deficit.
New mental status changes such as confusion or decreased level of consciousness can indicate fluid, electrolyte, or acid-base imbalance, especially hypo- or hypernatremia, acid-base imbalances, or fluid volume deficit.
Cardiac arrhythmias can be seen with acid-base imbalances and electrolyte imbalances, especially with hypo- or hyperkalemia and alkalosis. See Table 15.6a for a comparison of expected and unexpected findings and those that require notification of a health care provider.

Figure 15.15

Table 15.6a

Expected Findings Versus Unexpected Findings Indicating a Fluid Imbalance [ 2 ]

Review additional details about assessing these body systems in Open RN Nursing Skills .

Diagnostic and lab work.

Diagnostic tests and lab work provide important information about fluid status, electrolyte, and acid-base balance and should be used in conjunction with a thorough subjective and objective assessment to form a complete picture of the patient’s overall status. It is important to cluster diagnostic and lab assessment data with subjective and objective assessment data to ensure a complete assessment picture. This will help ensure correct information is reported to the provider as necessary.

Lab work provides important clues to overall fluid status. Common lab tests used to evaluate fluid status include serum osmolarity, urine specific gravity, hematocrit, and blood urea nitrogen (BUN).

Serum osmolarity (often interchanged with the term serum osmolality) measures the concentration of particles in the blood with a normal range of 275 to 295 mmol/kg). Normal value ranges may vary slightly among different laboratories. In healthy people, when serum osmolality in the blood becomes high, the body releases antidiuretic hormone (ADH). This hormone causes the kidneys to reabsorb water, resulting in dilution of the blood and the return of serum osmolarity to normal range. An elevated serum osmolarity level means the blood is more concentrated than normal and often indicates deficient fluid volume deficit. A decreased serum osmolarity means the blood is more dilute than normal and may indicate a fluid volume excess. [ 3 ]

Urine osmolarity measures the concentration of particles in the urine. An increased urine osmolarity result means the urine is concentrated and can indicate fluid volume deficit. A decreased urine osmolarity result means the urine is dilute and can indicate excess fluid intake. [ 4 ] Urine specific gravity is a urine test that commonly measures hydration status by measuring the concentration of particles in urine. Normal urine specific gravity levels are between 1.010 and 1.020. A urine specific gravity above 1.020 indicates concentrated urine and can indicate a fluid volume deficit, similarly to an elevated urine osmolarity. A urine specific gravity below 1.010 indicates dilute urine, which can occur with excessive fluid intake. [ 5 ]

When a condition called “ Excessive Fluid Volume ” occurs, altered physiological mechanisms impact the kidney’s ability to increase urine output to eliminate excessive fluid volume, causing urine output to decrease. As a result, the serum osmolarity decreases as fluid is retained but the urine specific gravity is elevated because urine is concentrated.

Hematocrit (HCT) is a blood test that measures how much of your blood is made up of red blood cells compared to the liquid component of blood called plasma. It is often part of a complete blood count (CBC), a routine test that measures different components of your blood. The normal hematocrit for men is 42 to 52%; for women it is 37 to 47%, but these ranges may vary slightly across labs.

In addition to measuring red blood cells, hematocrit levels can also be used to evaluate fluid balance. When deficient fluid volume is occurring, the plasma component of the blood also decreases, causing an elevated concentration of red blood cells (and an elevated hematocrit). In this case, drinking more fluid or receiving intravenous fluids will bring the hematocrit level back to normal range. Conversely, if a patient is experiencing “ Excessive Fluid Volume ,” the plasma component of the blood is increased, causing dilution of the red blood cells and a decreased hematocrit level. [ 6 ] , [ 7 ] See Figure 15.16 [ 8 ] for an illustration of normal hematocrit, elevated hematocrit, and decreased hematocrit due to fluid imbalance.

Figure 15.16

Effects of Fluid Imbalance on Hematocrit

Blood Urea Nitrogen (BUN) measures the amount of urea nitrogen in your blood. BUN and serum creatinine levels are used to evaluate kidney function, with increased levels indicating worsening kidney function. In general, the normal BUN range is 7 to 20 mg/dL, but normal ranges vary depending on the reference range used by the lab and the patient’s age. Patients with “ Deficient Fluid Volume” can also have elevated BUN levels for the same reason that hematocrit is affected; as plasma levels decrease, the blood becomes more concentrated.

In addition to monitoring lab work for results indicating fluid imbalance, electrolytes, specifically sodium, potassium, calcium, phosphorus, and magnesium, should be monitored closely for patients at risk. Refer to Table 15.4 in the “Electrolytes” section for an overview of electrolyte imbalances, common symptoms, and common treatments.

Additional diagnostic tests used to evaluate for signs of fluid and electrolyte imbalances are the chest X-ray and the electrocardiogram. A chest X-ray evaluates for fluid in the lungs, a common complication of excessive fluid volume. An electrocardiogram (ECG) evaluates for cardiac complications resulting from electrolyte imbalances.

Arterial blood gases are used to closely monitor critically ill patients, such as patients in diabetic ketoacidosis or in severe respiratory distress. ABG results provide important clues about respiratory status, oxygenation, and metabolic processes occurring in the body. See Table 15.6b for a summary of laboratory findings associated with fluid, electrolyte, and acid-base imbalances.

Table 15.6b

Lab Values Associated with Fluid and Electrolyte Imbalances

Life Span Considerations

There are several life span considerations when assessing for fluid, electrolyte, and acid-base balance.

NEWBORNS AND INFANTS

Newborns and infants have a large proportion of water weight compared to adults, with approximately 75% of weight being water. During the first week after birth, extracellular fluid is lost in urine along with sodium. Additionally, compensatory mechanisms such as the Renin-Angiotensin-Aldosterone System are less developed, and newborn kidneys are less able to concentrate urine, resulting in a decreased ability to retain sodium. Newborns and infants also have a greater body surface area, making them more susceptible to insensible fluid losses through the skin and lungs via evaporation. This causes increased risk of developing hyponatremia and fluid volume deficit. In contrast, newborns are less able to excrete potassium, placing them at risk for hyperkalemia. [ 9 ] Episodes of vomiting and diarrhea also place infants at an increased risk of quickly developing fluid and electrolyte disturbances.

When monitoring urine output in infants, parents are often asked about the number of wet diapers in a day. Nurses may also weigh diapers for hospitalized infants for more accurate measurement of urine output.

CHILDREN AND ADOLESCENTS

Children and adolescents are at risk for dehydration when physically active in hot environments causing excessive sweating. Illnesses causing diarrhea, vomiting, or fever can also quickly cause fluid deficit if there is little fluid intake to replace the water and sodium lost. For this reason, it is important to educate parents regarding the importance of fluid intake when their child is sweating or ill. [ 10 ]

OLDER ADULTS

Older adults are at risk for fluid and electrolyte imbalances for a variety of reasons, including surgery, chronic diseases such as heart and kidney disease, diuretic use, and decreased mobility that limits the ability to obtain hydration. They also have a decreased thirst reflex, which contributes to decreased fluid consumption. Kidney function naturally decreases with age, resulting in decreased sodium and water retention, as well as decreased potassium excretion. These factors place older patients at risk for fluid volume deficit and electrolyte abnormalities. [ 11 ]

There are many nursing diagnoses applicable to fluid, electrolyte, and acid-base imbalances. Review a nursing care planning resource for current NANDA-I approved nursing diagnoses, related factors, and defining characteristics. See Table 15.6c for commonly used NANDA-I diagnoses associated with patients with fluid and electrolyte imbalances. [ 12 ]

Table 15.6c

Common NANDA-I Nursing Diagnoses Related to Fluid and Electrolyte Imbalances [ 13 ]

Excess Fluid Volume Example

A patient with heart failure has been hospitalized with an acute exacerbation with dyspnea and increased edema in the lower extremities. A sample PES statement is, “Fluid Volume Excess related to a compromised regulatory mechanism as evidenced by edema, crackles in lower posterior lungs, and weight gain of 2 kg in 24 hours.”

Deficient Fluid Volume Example

An elderly patient develops severe diarrhea due to food poisoning and is admitted to the hospital with dehydration. A sample PES statement is, “Deficient Fluid Volume related to insufficient fluid intake as evidenced by blood pressure 90/60, dry mucous membranes, decreased urine output, and an increase in hematocrit.”

Risk for Imbalanced Fluid Volume Example

A patient who is ten weeks pregnant has developed severe vomiting due to severe morning sickness. A sample PES statement is, “Risk for Imbalanced Fluid Volume as evidenced by vomiting.” The nurse plans to educate the patient about tips to stay hydrated despite vomiting, as well as when to contact the provider if signs of dehydration develop.

Risk for Electrolyte Imbalance Example

A patient with chronic kidney disease is prescribed a diuretic to control fluid retention. A sample PES statement is, “Risk for Electrolyte Imbalance as evidenced by insufficient knowledge of modifiable factors.” The nurse plans to educate the patient about signs and symptoms of fluid and electrolyte imbalance and when to contact the provider.

Note: Recall that risk diagnoses do not contain related factors in PES statements because a vulnerability for a potential problem is being identified for the patient. Instead, the phrase “as evidenced by” is used to refer to the evidence of risk that exists. Read more about formulating PES statements in the “ Nursing Process ” chapter.

Outcome Identification

Goals for a patient experiencing fluid, electrolyte, or acid-base imbalances depend on the chosen nursing diagnosis and specific patient situation. Typically, goals should relate to resolution of the imbalance. For example, if the nursing diagnosis is Excess Fluid Volume , then an appropriate goal would pertain to resolution of the fluid volume excess. Remember that goals are broad and outcomes should be narrowly focused and written in SMART format (Specific, Measurable, Achievable, Realistic, and Time Oriented).

For the nursing diagnosis of Excess Fluid Volume , an overall goal is, “Patient will achieve fluid balance.” Fluid balance for a patient with Excess Fluid Volume is indicated by body weight returning to baseline with no peripheral edema, neck vein distention, or adventitious breath sounds. [ 14 ] An example of a SMART outcome is, “The patient will maintain clear lung sounds with no evidence of dyspnea over the next 24 hours.”

For patients experiencing Electrolyte Imbalances, an appropriate goal is, “Patient will maintain serum sodium, potassium, calcium, phosphorus, magnesium, and/or pH levels within normal range.” An additional goal is, “The patient will maintain a normal sinus heart rhythm with regular rate,” because many electrolyte imbalances impact the electrical conduction system of the heart and this is a life-threatening complication.

Planning Interventions

Evidence-based interventions should be planned according to the patient’s history and specific fluid, electrolyte, or acid-base imbalance present. Refer to a nursing care planning resource for evidence-based interventions for specific nursing diagnoses. Table 15.6d lists selected interventions for key imbalances. [ 15 ] , [ 16 ] , [ 17 ] , [ 18 ]

Table 15.6d

Interventions for Imbalances

Read more about medications affecting fluid and electrolyte balance, such as diuretics, in the “ Cardiovascular and Renal System ” chapter in Open RN Nursing Pharmacology .

Read about intravenous fluids used to treat Fluid Volume Deficit in the “ IV Therapy Management ” chapter in Open RN Nursing Skills .

Implement Interventions Safely

Patients with fluid and electrolyte imbalances can quickly move from one imbalance to another based on treatments received. It is vital to reassess a patient before implementing interventions to ensure current status warrants the prescribed intervention. For example, a patient admitted with Fluid Volume Deficit received intravenous fluids (IV) over the past 24 hours. When the nurse prepares to administer the next bag of IV fluids, she notices the patient has developed pitting edema in his lower extremities. She listens to his lungs and discovers crackles. The nurse notifies the prescribing provider, and the order for intravenous fluids is discontinued and a new order for diuretic medication is received.

Therefore, assessments for new or worsening imbalances should be performed prior to implementing interventions: [ 20 ]

Monitor daily weights for sudden changes. A weight change of greater than 1 kg in 24 hours (using the same scale and type of clothing) should be reported to the provider.
Monitor location and extent of edema using the 1+ to 4+ scale to quantify edema.
Monitor intake and output over a 24-hour period; note trends of decreasing urine output in relation to fluid intake indicating potential development of Fluid Volume Excess.
Monitor lab work such as serum osmolarity, serum sodium, BUN, and hematocrit for abnormalities. (For example, a patient receiving IV fluids may develop Fluid Volume Excess , resulting in decreased levels of serum osmolarity, serum sodium, BUN, and hematocrit. Conversely, a patient receiving IV diuretics can quickly become dehydrated, resulting in elevated levels of serum osmolarity, serum sodium, BUN, and hematocrit.)
For patients receiving intravenous fluids, monitor for the development of excessive fluid volume. Monitor lung sounds for crackles and ask about the presence of dyspnea. Report new abnormal findings to the provider.
For patients receiving diuretic therapy, monitor for fluid volume deficit and electrolyte imbalances such as hypokalemia and hyponatremia.

Implement fall precautions for patients with orthostatic hypotension, restlessness, anxiety, or confusion related to fluid imbalances.

The effectiveness of interventions implemented to maintain fluid balance must be continuously evaluated. Evaluation helps the nurse determine whether goals and outcomes are met and if interventions are still appropriate for the patient. If outcomes and goals are met, the plan of care can likely be discontinued. If outcomes and goals are not met, they may need to be revised. It is also possible that interventions may need to be added or revised to help the patient meet their goals and outcomes. Table 15.6e provides a list of assessment findings indicating imbalances are improved.

Table 15.6e

Evaluating for Improvement of Imbalances

15.7. PUTTING IT ALL TOGETHER

Patient scenario.

Mr. Hernandez is a 54-year-old patient admitted to the medical telemetry floor with a diagnosis of heart failure exacerbation. He tells the nurse, “My breathing has gotten worse the past last three days and I have a lot of swelling in my feet.”

Applying the Nursing Process

Assessment: Vital signs at the start of shift were blood pressure 154/94, heart rate 88, respiratory rate 24, and oxygen saturation 88%. On assessment, the nurse finds fine crackles in bilateral posterior lower lung bases, an S3 heart sound, and 2+ pitting edema in bilateral lower extremities midway to the knee. The nurse reviews the patient’s chart and discovers Mr. Hernandez has gained 10 pounds since his previous office visit last week.

Based on the assessment information that has been gathered, the nurse creates the following nursing care plan for Mr. Hernandez:

Nursing Diagnosis: Excess Fluid Volume related to compromised regulatory mechanism as evidenced by fine crackles in bilateral posterior lung bases, S3 heart sound, weight gain of 10 pounds in the past week, and the patient states, “My breathing has gotten worse the past last three days and I have a lot of swelling in my feet.”

Overall Goal: The patient will demonstrate stabilization in fluid volume.

SMART Expected Outcomes:

Mr. Hernandez’s vital signs and weight will return to his baseline in the next 48 hours.
Mr. Hernandez will verbalize three rules of dietary and fluid restriction to follow at home following his educational session.

Planning and Implementing Nursing Interventions:

The nurse will weigh the patient daily and analyze weight trends and 24-hour intake and output. The nurse will closely monitor lung sounds, respiratory rate, and oxygenation status. The nurse will establish a 24-hour schedule for fluid intake and educate the patient regarding fluid restriction. The nurse will closely monitor lab results, especially sodium and potassium, and monitor for symptoms of fluid shifts. The nurse will provide patient education regarding fluid and sodium restrictions.

Sample Documentation:

The patient was admitted with acute heart failure exacerbation and stated, “My breathing has gotten worse the past last three days and I have a lot of swelling in my feet.” On admission to the unit at 0900, vital signs were blood pressure 154/94, heart rate 88, respiratory rate 24, and oxygen saturation 88%. Fine crackles were present in bilateral posterior lower lung bases, an S3 heart sound was present, and there was 2+ pitting edema in bilateral lower extremities midway to the knee. The chart indicates he has gained 10 pounds since his previous office visit last week. Provider orders and fluid restrictions were implemented. Lab results are within normal ranges. Patient education regarding fluid and sodium restrictions and a handout were provided. At the end of the session, Mr. Hernandez was able to report back three rules of dietary and fluid restrictions to follow at home when discharged.

Evaluation:

By the end of the shift, the second SMART outcome was “met” when Mr. Hernandez was able to report back three rules of dietary and fluid restrictions after the patient education session. The first SMART outcome was not yet met but will be reevaluated every shift for the next 24 hours.

5.8. LEARNING ACTIVITIES

Learning activities.

(Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.)

Scenario A [ 1 ]

Mr. Smith, a 60-year-old male, was admitted to the general medical floor with a diagnosis of an exacerbation of heart failure. See Figure 15.17 for an image of Mr. Smith. [ 2 ] He has a past medical history of hypertension and coronary artery disease. His admitting weight was 225 pounds. His baseline weight from a previous clinic visit was 210 pounds. On admission, he had fine crackles throughout his lower posterior lobes and 4+ pitting edema in his lower extremities. His ABG results on admission were: pH 7.30, PaCO2 50 mmHg, PaO2 80 mm Hg, HCO3- 21 mEq/L, SaO2 85%.

Figure 15.17

Interpret Mr. Smith’s ABG results on admission.

Explain the likely cause of the ABG results.

Create a nursing diagnosis for Mr. Smith’s fluid status in PES format based on his admission data.

Mr. Smith has received multiple doses of IV diuretics over the past three days since admission. During your morning assessment, Mr. Smith tells you he very thirsty and feels dizzy. You notice he is irritable and is becoming increasingly confused. You quickly obtain his vital signs: BP 85/45, HR 110, RR 24/minute, O2 saturation 98% on 2L/min per nasal cannula, and temperature 37.2 degrees Celsius. His lung sounds are clear and his heart sounds are regular sinus rhythm. You notice his weight this morning was 205 pounds. You call the provider and receive orders for STAT Basic Metabolic Panel and to initiate 0.9% Normal Saline IV fluids at 250 mL/hour until the provider arrives to evaluate the patient.

The Basic Metabolic Panel results (with the lab’s normal reference range in parentheses) are:

Sodium: 155 mEq/L (135-145)

Potassium: 3.3 mEq/L (3.5-5.3)

Chloride: 103 mEq/L (98-108)

Carbon dioxide: 25 mEq/L (23-27)

Blood urea nitrogen (BUN): 30 mg/dL (10-25)

Creatinine: 1.9 mg/dL (0.5-1.5)

Glucose: 100 mg/dL (fasting 70-99)

What is Mr. Smith’s fluid balance this morning? Support your answer with data.

What is the probable cause of his fluid balance?

Interpret Mr. Smith’s lab results. What are the potential causes of these results?

Create a nursing diagnosis statement in PES format for Mr. Smith’s current fluid status.

Create a new expected outcome in SMART format for Mr. Smith.

In addition to providing intravenous fluids, what additional interventions will you implement for Mr. Smith?

How will you evaluate if the nursing interventions are effective?

Scenario B [ 3 ]

A 74-year-old male, Mr. M., was admitted to the general medical floor during the night shift with a diagnosis of pneumonia. See Figure 15.18 for an image of Mr. M. [ 4 ] He has a past medical history of alcohol abuse and coronary artery disease. You are the day shift nurse, and during your morning assessment you notice that Mr. M. becomes increasingly lethargic and is not following commands consistently. You obtain the following vital signs: BP 80/45, HR 110, RR 8 and labored, O2 saturation 80% on 3L per nasal cannula, temperature 38.1 degrees Celsius. His lung sounds reveal coarse crackles throughout, and you notice he is using accessory muscles with breathing. You notify the provider using an SBAR report and receive orders to increase oxygen to 10L per non-rebreather mask.

Figure 15.18

Lab results are ordered with the following results:

ABGs: pH 7.30, PaCO2 50, PaO2 59, HCO3 24, SaO2 80

Potassium: 5.9 mEq/L

Magnesium: 1.0 mEq/L

Calcium: 10.2 mg/dL

Sodium: 137 mEq/L

Hematocrit: 55%

Serum Osmolarity: 305 mmol/kg

BUN: 30 mg/dL

Urine Specific Gravity: 1.025

What is Mr. M.’s fluid balance? Provide data supporting the imbalance.

What is your interpretation of Mr. M.’s ABGs?

What is your interpretation of Mr. M.’s electrolyte studies?

Is Mr. M. stable or unstable? Why?

For what complications will you monitor?

Write an SBAR communication you would have with the health care provider to notify them about Mr. M.’s condition.

Create a NANDA-I diagnosis for Mr. M. in PES format.

Identify an expected outcome for Mr. M. in SMART format.

What interventions will you plan for Mr. M.?

How will you evaluate if your interventions are effective?

Write a nursing note about Mr. M.’s condition and your actions taken. This can be in the form of a DAR, SOAP, or summary nursing note.

XV GLOSSARY

Movement of solutes and ions across a cell membrane against a concentration gradient from an area of lower concentration to an area of higher concentration using energy during the process.

An assessment sign of acute hypocalcemia characterized by involuntary facial muscle twitching when the facial nerve is tapped.

The movement of solute particles from an area of higher concentration to an area of lower concentration.

Swelling caused by excessive interstitial fluid retention.

Fluids found outside cells in the intravascular or interstitial spaces.

Movement of fluids through a permeable membrane utilizing hydrostatic pressure.

The pressure that a contained fluid exerts on what is confining it.

Elevated levels of retained carbon dioxide in the body.

Intravenous fluids with a higher concentration of dissolved particles than blood plasma.

Excess intravascular fluid. Used interchangeably with “excessive fluid volume.”

Intravenous fluids with a lower concentration of dissolved particles than blood plasma.

Intravascular fluid loss. Used interchangeably with “deficient fluid volume” and “dehydration.”

Fluids found between the cells and outside of the vascular system.

Fluids found inside cells consisting of protein, water, and electrolytes.

Fluids found in the vascular system consisting of the body’s arteries, veins, and capillary networks.

Intravenous fluids with a similar concentration of dissolved particles as blood plasma.

Pressure inside the vascular compartment created by protein content of the blood (in the form of albumin) that holds water inside the blood vessels.

Proportion of dissolved particles in a specific weight of fluid.

Proportion of dissolved particles or solutes in a specific volume of fluid.

Movement of fluid through a semipermeable membrane from an area of lesser solute concentration to an area of greater solute concentration.

Movement of fluids or solutes down a concentration gradient where no energy is used during the process.

A body system that regulates extracellular fluids and blood pressure by regulating fluid output and electrolyte excretion.

A sign associated with hypocalcemia that causes a spasm of the hand when a blood pressure cuff is inflated.

A measurement of hydration status that measures the concentration of particles in urine.

Licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit https://creativecommons.org/licenses/by/4.0/ .

Cite this Page Open Resources for Nursing (Open RN); Ernstmeyer K, Christman E, editors. Nursing Fundamentals [Internet]. Eau Claire (WI): Chippewa Valley Technical College; 2021. Chapter 15 Fluids and Electrolytes.
PDF version of this title (216M)

In this Page

FLUIDS AND ELECTROLYTES INTRODUCTION
BASIC FLUID AND ELECTROLYTE CONCEPTS
INTRAVENOUS SOLUTIONS
ELECTROLYTES
ACID-BASE BALANCE
APPLYING THE NURSING PROCESS
PUTTING IT ALL TOGETHER
LEARNING ACTIVITIES

Other titles in this collection

Open RN OER Textbooks

Bulk Download

Bulk download content from FTP

Related information

PMC PubMed Central citations
PubMed Links to PubMed

Recent Activity

Chapter 15 Fluids and Electrolytes - Nursing Fundamentals Chapter 15 Fluids and Electrolytes - Nursing Fundamentals

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

Connect with NLM

National Library of Medicine 8600 Rockville Pike Bethesda, MD 20894

Web Policies FOIA HHS Vulnerability Disclosure

Help Accessibility Careers

26.3 Electrolyte Balance

Learning objectives.

By the end of this section, you will be able to:

List the role of the six most important electrolytes in the body
Name the disorders associated with abnormally high and low levels of the six electrolytes
Identify the predominant extracellular anion
Describe the role of aldosterone on the level of water in the body

The body contains a large variety of ions, or electrolytes, which perform a variety of functions. Some ions assist in the transmission of electrical impulses along cell membranes in neurons and muscles. Other ions help to stabilize protein structures in enzymes. Still others aid in releasing hormones from endocrine glands. All of the ions in plasma contribute to the osmotic balance that controls the movement of water between cells and their environment.

Electrolytes in living systems include sodium, potassium, chloride, bicarbonate, calcium, phosphate, magnesium, copper, zinc, iron, manganese, molybdenum, copper, and chromium. In terms of body functioning, six electrolytes are most important: sodium, potassium, chloride, bicarbonate, calcium, and phosphate.

Roles of Electrolytes

These six ions aid in nerve excitability, endocrine secretion, membrane permeability, buffering body fluids, and controlling the movement of fluids between compartments. These ions enter the body through the digestive tract. More than 90 percent of the calcium and phosphate that enters the body is incorporated into bones and teeth, with bone serving as a mineral reserve for these ions. In the event that calcium and phosphate are needed for other functions, bone tissue can be broken down to supply the blood and other tissues with these minerals. Phosphate is a normal constituent of nucleic acids; hence, blood levels of phosphate will increase whenever nucleic acids are broken down.

Excretion of ions occurs mainly through the kidneys, with lesser amounts lost in sweat and in feces. Excessive sweating may cause a significant loss, especially of sodium and chloride. Severe vomiting or diarrhea will cause a loss of chloride and bicarbonate ions. Adjustments in respiratory and renal functions allow the body to regulate the levels of these ions in the ECF.

Table 26.1 lists the reference values for blood plasma, cerebrospinal fluid (CSF), and urine for the six ions addressed in this section. In a clinical setting, sodium, potassium, and chloride are typically analyzed in a routine urine sample. In contrast, calcium and phosphate analysis requires a collection of urine across a 24-hour period, because the output of these ions can vary considerably over the course of a day. Urine values reflect the rates of excretion of these ions. Bicarbonate is the one ion that is not normally excreted in urine; instead, it is conserved by the kidneys for use in the body’s buffering systems.

Sodium is the major cation of the extracellular fluid. It is responsible for one-half of the osmotic pressure gradient that exists between the interior of cells and their surrounding environment. People eating a typical Western diet, which is very high in NaCl, routinely take in 130 to 160 mmol/day of sodium, but humans require only 1 to 2 mmol/day. This excess sodium appears to be a major factor in hypertension (high blood pressure) in some people. Excretion of sodium is accomplished primarily by the kidneys. Sodium is freely filtered through the glomerular capillaries of the kidneys, and although much of the filtered sodium is reabsorbed in the proximal convoluted tubule, some remains in the filtrate and urine, and is normally excreted.

Hyponatremia is a lower-than-normal concentration of sodium, usually associated with excess water accumulation in the body, which dilutes the sodium. An absolute loss of sodium may be due to a decreased intake of the ion coupled with its continual excretion in the urine. An abnormal loss of sodium from the body can result from several conditions, including excessive sweating, vomiting, or diarrhea; the use of diuretics; excessive production of urine, which can occur in diabetes; and acidosis, either metabolic acidosis or diabetic ketoacidosis.

A relative decrease in blood sodium can occur because of an imbalance of sodium in one of the body’s other fluid compartments, like IF, or from a dilution of sodium due to water retention related to edema or congestive heart failure. At the cellular level, hyponatremia results in increased entry of water into cells by osmosis, because the concentration of solutes within the cell exceeds the concentration of solutes in the now-diluted ECF. The excess water causes swelling of the cells; the swelling of red blood cells—decreasing their oxygen-carrying efficiency and making them potentially too large to fit through capillaries—along with the swelling of neurons in the brain can result in brain damage or even death.

Hypernatremia is an abnormal increase of blood sodium. It can result from water loss from the blood, resulting in the hemoconcentration of all blood constituents. This can lead to neuromuscular irritability, convulsions, CNS lethargy, and coma. Hormonal imbalances involving ADH and aldosterone may also result in higher-than-normal sodium values.

Potassium is the major intracellular cation. It helps establish the resting membrane potential in neurons and muscle fibers after membrane depolarization and action potentials. In contrast to sodium, potassium has very little effect on osmotic pressure. The low levels of potassium in blood and CSF are due to the sodium-potassium pumps in cell membranes, which maintain the normal potassium concentration gradients between the ICF and ECF. The recommendation for daily intake/consumption of potassium is 4700 mg. Potassium is excreted, both actively and passively, through the renal tubules, especially the distal convoluted tubule and collecting ducts. Potassium participates in the exchange with sodium in the renal tubules under the influence of aldosterone, which also relies on basolateral sodium-potassium pumps.

Hypokalemia is an abnormally low potassium blood level. Similar to the situation with hyponatremia, hypokalemia can occur because of either an absolute reduction of potassium in the body or a relative reduction of potassium in the blood due to the redistribution of potassium. An absolute loss of potassium can arise from decreased intake, frequently related to starvation. It can also come about from vomiting, diarrhea, or alkalosis. Hypokalemia can cause metabolic acidosis, CNS confusion, and cardiac arrhythmias.

Some insulin-dependent diabetic patients experience a relative reduction of potassium in the blood from the redistribution of potassium. When insulin is administered and glucose is taken up by cells, potassium passes through the cell membrane along with glucose, decreasing the amount of potassium in the blood and IF, which can cause hyperpolarization of the cell membranes of neurons, reducing their responses to stimuli.

Hyperkalemia , an elevated potassium blood level, also can impair the function of skeletal muscles, the nervous system, and the heart. Hyperkalemia can result from increased dietary intake of potassium. In such a situation, potassium from the blood ends up in the ECF in abnormally high concentrations. This can result in a partial depolarization (excitation) of the plasma membrane of skeletal muscle fibers, neurons, and cardiac cells of the heart, and can also lead to an inability of cells to repolarize. For the heart, this means that it won’t relax after a contraction, and will effectively “seize” and stop pumping blood, which is fatal within minutes. Because of such effects on the nervous system, a person with hyperkalemia may also exhibit mental confusion, numbness, and weakened respiratory muscles.

Chloride is the predominant extracellular anion. Chloride is a major contributor to the osmotic pressure gradient between the ICF and ECF, and plays an important role in maintaining proper hydration. Chloride functions to balance cations in the ECF, maintaining the electrical neutrality of this fluid. The paths of secretion and reabsorption of chloride ions in the renal system follow the paths of sodium ions.

Hypochloremia , or lower-than-normal blood chloride levels, can occur because of defective renal tubular absorption. Vomiting, diarrhea, and metabolic acidosis can also lead to hypochloremia. Hyperchloremia , or higher-than-normal blood chloride levels, can occur due to dehydration, excessive intake of dietary salt (NaCl) or swallowing of sea water, aspirin intoxication, congestive heart failure, and the hereditary, chronic lung disease, cystic fibrosis. In people who have cystic fibrosis, chloride levels in sweat are two to five times those of normal levels, and analysis of sweat is often used in the diagnosis of the disease.

External Website

Watch this video to see an explanation of the effect of seawater on humans. What effect does drinking seawater have on the body?

Bicarbonate

Bicarbonate is the second most abundant anion in the blood. Its principal function is to maintain your body’s acid-base balance by being part of buffer systems. This role will be discussed in a different section.

Bicarbonate ions result from a chemical reaction that starts with carbon dioxide (CO 2 ) and water, two molecules that are produced at the end of aerobic metabolism. Only a small amount of CO 2 can be dissolved in body fluids. Thus, over 90 percent of the CO 2 is converted into bicarbonate ions, HCO 3 – , through the following reactions:

The bidirectional arrows indicate that the reactions can go in either direction, depending on the concentrations of the reactants and products. Carbon dioxide is produced in large amounts in tissues that have a high metabolic rate. Carbon dioxide is converted into bicarbonate in the cytoplasm of red blood cells through the action of an enzyme called carbonic anhydrase. Bicarbonate is transported in the blood. Once in the lungs, the reactions reverse direction, and CO 2 is regenerated from bicarbonate to be exhaled as metabolic waste.

About two pounds of calcium in your body are bound up in bone, which provides hardness to the bone and serves as a mineral reserve for calcium and its salts for the rest of the tissues. Teeth also have a high concentration of calcium within them. A little more than one-half of blood calcium is bound to proteins, leaving the rest in its ionized form. Calcium ions, Ca 2+ , are necessary for muscle contraction, enzyme activity, and blood coagulation. In addition, calcium helps to stabilize cell membranes and is essential for the release of neurotransmitters from neurons and of hormones from endocrine glands.

Calcium is absorbed through the intestines under the influence of activated vitamin D. A deficiency of vitamin D leads to a decrease in absorbed calcium and, eventually, a depletion of calcium stores from the skeletal system, potentially leading to rickets in children and osteomalacia in adults, contributing to osteoporosis.

Hypocalcemia , or abnormally low calcium blood levels, is seen in hypoparathyroidism, which may follow the removal of the thyroid gland, because the four nodules of the parathyroid gland are embedded in it. This can lead to cardiac depression, increased neuromuscular excitability, muscular cramps, and skeltal weakness. Hypercalcemia , or abnormally high calcium blood levels, is seen in primary hyperparathyroidism. This can lead to cardiac arrhythmias and arrest, muscle weakness, CNS confusion, and coma. Some malignancies may also result in hypercalcemia.

Phosphate is present in the body in three ionic forms: H 2 PO 4− , HPO42, and PO43−. The most common form is HPO42−HPO42−. Bone and teeth bind up 85 percent of the body’s phosphate as part of calcium-phosphate salts. Phosphate is found in phospholipids, such as those that make up the cell membrane, and in ATP, nucleotides, and buffers.

Hypophosphatemia , or abnormally low phosphate blood levels, occurs with heavy use of antacids, during alcohol withdrawal, and during malnourishment. In the face of phosphate depletion, the kidneys usually conserve phosphate, but during starvation, this conservation is impaired greatly. Hyperphosphatemia , or abnormally increased levels of phosphates in the blood, occurs if there is decreased renal function or in cases of acute lymphocytic leukemia. Additionally, because phosphate is a major constituent of the ICF, any significant destruction of cells can result in dumping of phosphate into the ECF.

Regulation of Sodium and Potassium

Sodium is reabsorbed from the renal filtrate, and potassium is excreted into the filtrate in the renal collecting tubule. The control of this exchange is governed principally by two hormones—aldosterone and angiotensin II.

Aldosterone

Recall that aldosterone increases the excretion of potassium and the reabsorption of sodium in the distal tubule. Aldosterone is released if blood levels of potassium increase, if blood levels of sodium severely decrease, or if blood pressure decreases. Its net effect is to conserve and increase water levels in the plasma by reducing the excretion of sodium, and thus water, from the kidneys. In a negative feedback loop, increased osmolality of the ECF (which follows aldosterone-stimulated sodium absorption) inhibits the release of the hormone ( Figure 26.3.1 ).

Angiotensin II

Angiotensin II causes vasoconstriction and an increase in systemic blood pressure. This action increases the glomerular filtration rate, resulting in more material filtered out of the glomerular capillaries and into Bowman’s capsule. Angiotensin II also signals an increase in the release of aldosterone from the adrenal cortex.

In the distal convoluted tubules and collecting ducts of the kidneys, aldosterone stimulates the synthesis and activation of the sodium-potassium pump ( Figure 26.3.2 ). Sodium passes from the filtrate, into and through the cells of the tubules and ducts, into the ECF and then into capillaries. Water follows the sodium due to osmosis. Thus, aldosterone causes an increase in blood sodium levels and blood volume. Aldosterone’s effect on potassium is the reverse of that of sodium; under its influence, excess potassium is pumped into the renal filtrate for excretion from the body.

This figure shows the hormone cascade that that increases kidney reabsorption of NA plus and water. In the first step, the kidneys release renin into the blood stream. The blood stream is depicted with a red arrow pointing from left to right. At the same time, the liver releases angiotensinogen into the blood, which combines with the renin, yielding angiotensin one. The blood flow then leads to the lungs. Within the pulmonary blood, angiotensin-converting enzyme (ACE) converts angiotensin one to angiotensin two. The blood then flows to the adrenal cortex, where angiotensin two stimulates the adrenal cortex to secrete aldosterone. Aldosterone causes the kidney tubules to increase reabsorption of NA plus and water into the blood.

Regulation of Calcium and Phosphate

Calcium and phosphate are both regulated through the actions of three hormones: parathyroid hormone (PTH), dihydroxyvitamin D (calcitriol), and calcitonin. All three are released or synthesized in response to the blood levels of calcium.

PTH is released from the parathyroid gland in response to a decrease in the concentration of blood calcium. The hormone activates osteoclasts to break down bone matrix and release inorganic calcium-phosphate salts. PTH also increases the gastrointestinal absorption of dietary calcium by converting vitamin D into dihydroxyvitamin D (calcitriol), an active form of vitamin D that intestinal epithelial cells require to absorb calcium.

PTH raises blood calcium levels by inhibiting the loss of calcium through the kidneys. PTH also increases the loss of phosphate through the kidneys.

Calcitonin is released from the thyroid gland in response to elevated blood levels of calcium. The hormone increases the activity of osteoblasts, which remove calcium from the blood and incorporate calcium into the bony matrix.

Chapter Review

Electrolytes serve various purposes, such as helping to conduct electrical impulses along cell membranes in neurons and muscles, stabilizing enzyme structures, and releasing hormones from endocrine glands. The ions in plasma also contribute to the osmotic balance that controls the movement of water between cells and their environment. Imbalances of these ions can result in various problems in the body, and their concentrations are tightly regulated. Aldosterone and angiotensin II control the exchange of sodium and potassium between the renal filtrate and the renal collecting tubule. Calcium and phosphate are regulated by PTH, calcitrol, and calcitonin.

Interactive Link Questions

Drinking seawater dehydrates the body as the body must pass sodium through the kidneys, and water follows.

Review Questions

Critical thinking questions.

1. Explain how the CO 2 generated by cells and exhaled in the lungs is carried as bicarbonate in the blood.

2. How can one have an imbalance in a substance, but not actually have elevated or deficient levels of that substance in the body?

Answers for Critical Thinking Questions

Very little of the carbon dioxide in the blood is carried dissolved in the plasma. It is transformed into carbonic acid and then into bicarbonate in order to mix in plasma for transportation to the lungs, where it reverts back to its gaseous form.
Without having an absolute excess or deficiency of a substance, one can have too much or too little of that substance in a given compartment. Such a relative increase or decrease is due to a redistribution of water or the ion in the body’s compartments. This may be due to the loss of water in the blood, leading to a hemoconcentration or dilution of the ion in tissues due to edema.

This work, Anatomy & Physiology, is adapted from Anatomy & Physiology by OpenStax , licensed under CC BY . This edition, with revised content and artwork, is licensed under CC BY-SA except where otherwise noted.

Images, from Anatomy & Physiology by OpenStax , are licensed under CC BY except where otherwise noted.

Access the original for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction .

Anatomy & Physiology Copyright © 2019 by Lindsay M. Biga, Staci Bronson, Sierra Dawson, Amy Harwell, Robin Hopkins, Joel Kaufmann, Mike LeMaster, Philip Matern, Katie Morrison-Graham, Kristen Oja, Devon Quick, Jon Runyeon, OSU OERU, and OpenStax is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License , except where otherwise noted.

An official website of the United States government

Here’s how you know

Official websites use .gov A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS A lock ( Lock Locked padlock icon ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Health Topics
Drugs & Supplements
Medical Tests
Medical Encyclopedia
About MedlinePlus
Customer Support

Fluid and Electrolyte Balance

Diagnosis and tests, related issues, see, play and learn.

No links available

Clinical Trials

Journal Articles

Find an Expert

Patient handouts, what are electrolytes.

Electrolytes are minerals that have an electric charge when they are dissolved in water or body fluids, including blood. The electric charge can be positive or negative. You have electrolytes in your blood, urine (pee), tissues, and other body fluids.

Electrolytes are important because they help:

Balance the amount of water in your body
Balance your body's acid/base (pH) level
Move nutrients into your cells
Move wastes out of your cells
Support your muscle and nerve function
Keep your heart rate and rhythm steady
Keep your blood pressure stable
Keep your bones and teeth healthy

What are the different types of electrolytes in your body?

The main electrolytes in your body include:

Bicarbonate, which helps maintain the body's acid and base balance (pH). It also plays an important role in moving carbon dioxide through the bloodstream.
Calcium , which helps make and keep bones and teeth strong.
Chloride, which also helps control the amount of fluid in the body. In addition, it helps maintain healthy blood volume and blood pressure.
Magnesium, which helps your muscles, nerves, and heart work properly. It also helps control blood pressure and blood glucose (blood sugar).
Phosphate, which works together with calcium to build strong bones and teeth.
Potassium , which helps your cells, heart, and muscles work properly.
Sodium , which helps control the amount of fluid in the body. It also helps your nerves and muscles work properly.

You get these electrolytes from the foods you eat and the fluids you drink.

What is an electrolyte imbalance?

An electrolyte imbalance means that the level of one or more electrolytes in your body is too low or too high. It can happen when the amount of water in your body changes. The amount of water that you take in should equal the amount you lose. If something upsets this balance, you may have too little water ( dehydration ) or too much water (overhydration). Some of the more common reasons why you might have an imbalance of the water in your body include:

Certain medicines
Severe vomiting and/or diarrhea
Heavy sweating
Heart , liver or kidney problems
Not drinking enough fluids, especially when doing intense exercise or when the weather is very hot
Drinking too much water

What are the different types of electrolyte imbalances?

The names of the different types of electrolyte imbalances are:

How are electrolyte imbalances diagnosed?

A test called an electrolyte panel can check the levels of your body's main electrolytes. A related test, the anion gap blood test , checks whether your electrolytes are out of balance or if your blood is too acidic or not acidic enough.

What are the treatments for electrolyte imbalances?

The treatment for an electrolyte imbalance depends on which electrolytes are out of balance, if there is too little or too many, and what is causing the imbalance. In minor cases, you may just need to make some changes to your diet. In other cases, you may need other treatments. For example:

If you don't have enough of an electrolyte, you may get electrolyte replacement therapy. This involves giving you more of that electrolyte. It could be a medicine or supplement that you swallow or drink, or it may be given intravenously (by IV).
If you have too much of an electrolyte, your provider may give you medicines or fluids (by mouth or by IV) to help remove that electrolyte from your body. In severe cases, you may need dialysis to filter out the electrolyte.
About Body Water (Merck & Co., Inc.) Also in Spanish

Nutrition and Healthy Eating: How Much Water Should You Drink Each Day? (Mayo Foundation for Medical Education and Research) Also in Spanish

Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)

Article: The moderating effect of fluid overload on the relationship between the...
Article: Controversies Surrounding Albumin Use in Sepsis: Lessons from Cirrhosis.
Article: The effects of a sugar-free amino acid-containing electrolyte beverage on 5-kilometer...
Fluid and Electrolyte Balance -- see more articles
Centers for Disease Control and Prevention Also in Spanish
Food and Nutrition Information Center
Basic Blood Chemistry Tests (For Parents) (Nemours Foundation)
Aldosterone blood test (Medical Encyclopedia) Also in Spanish
Antidiuretic hormone blood test (Medical Encyclopedia) Also in Spanish
Basic metabolic panel (Medical Encyclopedia) Also in Spanish
Electrolytes (Medical Encyclopedia) Also in Spanish
Fluid imbalance (Medical Encyclopedia) Also in Spanish
Magnesium deficiency (Medical Encyclopedia) Also in Spanish
Osmolality blood test (Medical Encyclopedia) Also in Spanish
Urine specific gravity test (Medical Encyclopedia) Also in Spanish

The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.

Textbook of General Pathology for Dental Students pp 111–114 Cite as

Imbalances in Fluids and Electrolytes, Acids and Bases: An Overview

S. R. Prabhu 2
First Online: 04 July 2023

257 Accesses

1 Citations

59 Altmetric

Fluid and electrolyte balances are essential in maintaining appropriate blood volume and homeostasis. Electrolyte balance also plays a critical role in protecting cellular function, tissue perfusion, and acid-base balance. The most severe electrolyte disturbances involve abnormalities in the levels of sodium, potassium, and calcium. The body uses different mechanisms to control the blood’s acid-base balance. The body’s acid-base mechanisms involve the lungs, kidneys, and buffer systems. Acidosis and alkalosis occur when the acid-base balance is abnormal. This chapter briefly describes abnormalities that can occur when imbalances in fluids, electrolytes, and acid bases develop.

This is a preview of subscription content, log in via an institution .

Buying options

Available as PDF
Read on any device
Instant download
Own it forever
Available as EPUB and PDF
Durable hardcover edition
Dispatched in 3 to 5 business days
Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Bibliography

Berkelhammer C, Bear RA. A clinical approach to common electrolyte problems: 3. Hypophosphatemia. Can Med Assoc J. 1984;130(1):17–23.

PubMed PubMed Central Google Scholar

Boden SD, Kaplan FS. Calcium homeostasis. Orthop Clin North Am. 1990;21(1):31–42.

Article PubMed Google Scholar

Cooper MS, Gittoes NJ. Diagnosis and management of hypocalcaemia. BMJ. 2008;336(7656):1298–302.

Article PubMed PubMed Central Google Scholar

Hamm LL, Nakhoul N, Hering-Smith KS. Acid-base homeostasis. Clin J Am Soc Nephrol. 2015;10(12):2232–42.

Hopkins E, Sanvictores T, Sharma S. Physiology. Acid-base balance. Treasure Island (FL): StatPearls Publishing; 2023. https://www.ncbi.nlm.nih.gov/books/NBK507807/ .

Google Scholar

Lewis JL III. Acidosis - hormonal and metabolic disorders. MSD Manuals; 2022a. https://www.msdmanuals.com/en-au/home/hormonal-and-metabolic-disorders/acid-base-balance/acidosis .

Lewis JL III. Alkalosis - hormonal and metabolic disorders. MSD Manuals; 2022b. https://www.msdmanuals.com/en-au/home/hormonal-and-metabolic-disorders/acid-base-balance/alkalosis .

Liamis G, Liberopoulos E, Barkas F, Elisaf M. Spurious electrolyte disorders: a diagnostic challenge for clinicians. Am J Nephrol. 2013;38(1):50–7.

Palmer LG, Schnermann J. Integrated control of Na transport along the nephron. Clin J Am Soc Nephrol. 2015;10(4):676–87.

Turner JJO. Hypercalcaemia - presentation and management. Clin Med (Lond). 2017;17(3):270–3.

Veldurthy V, Wei R, Oz L, Dhawan P, Jeon YH, Christakos S. Vitamin D, calcium homeostasis and ageing. Bone Res. 2016;4:16041.

Viera AJ, Wouk N. Potassium disorders: hypokalaemia and hypersalemia. Am Fam Physician. 2015;92(6):487–95.

PubMed Google Scholar

Download references

Author information

Authors and affiliations.

School of Dentistry, University of Queensland, Brisbane, QLD, Australia

S. R. Prabhu

You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to S. R. Prabhu .

Rights and permissions

Reprints and permissions

Copyright information

About this chapter

Cite this chapter.

Prabhu, S.R. (2023). Imbalances in Fluids and Electrolytes, Acids and Bases: An Overview. In: Textbook of General Pathology for Dental Students. Springer, Cham. https://doi.org/10.1007/978-3-031-31244-1_14

Download citation

DOI : https://doi.org/10.1007/978-3-031-31244-1_14

Published : 04 July 2023

Publisher Name : Springer, Cham

Print ISBN : 978-3-031-31243-4

Online ISBN : 978-3-031-31244-1

eBook Packages : Medicine Medicine (R0)

Share this chapter

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

Publish with us

Policies and ethics

Find a journal
Track your research

Fluid and Electrolyte Imbalances: Interpretation and Assessment

Affiliation.

1 University of Louisville Hospital, Louisville, Kentucky. Mandi D. Walker, MSN, RN-BC, CCRN, has more than 11 years of critical care experience. She currently serves as the critical care advanced practice educator at University of Louisville Hospital in Louisville, Kentucky. She obtained a BSN from the University of Louisville and an MSN in education from Walden University, which is based in Minneapolis, Minnesota. She is certified in critical care and nursing professional development.
PMID: 27828935
DOI: 10.1097/NAN.0000000000000193

Maintaining the balance of fluid and electrolytes is crucial to the care of patients across the continuum. To do this, a practitioner must be cognizant of key monitoring and assessment parameters. Key electrolytes, their function within the body, normal values, signs and symptoms of imbalances, key treatment modalities, and other considerations are discussed.

Electrolytes
Fluid Therapy*
Nursing Assessment
Water-Electrolyte Balance*
Water-Electrolyte Imbalance*

Nursing: Complex Health Alterations 1 Resource Guide

Respiratory
Fluid and Electrolyte Balance
Acid-Base Balance
NCLEX Info and Resources This link opens in a new window
Nursing Program Guide This link opens in a new window
Other Health Science Guides This link opens in a new window

Topic Review: A lterations in Fluid and Electrolyte Balance

Understand the basics.

These resources offer a high level overview and are a good place to start if you're very confused or need to review.

These resources offer more detail and additional information.

Apply and Evaluate

Keep Learning

Use a nursing database to search for further explanation, case studies, journal articles and more:

Search for open educational resources (OER) or additional online materials such as tutorials, practice quizzes, learning objects, and more:

<< Previous: Endocrine
Next: Acid-Base Balance >>
Last Updated: Aug 31, 2023 3:41 PM
URL: https://westerntc.libguides.com/CHA1

COMMENTS

Fluid and Electrolytes, Acid-Base Balance
Fluid and electrolyte balance is a dynamic process that is crucial for life and homeostasis. Fluid occupies almost 60% of the weight of an adult.; Body fluid is located in two fluid compartments: the intracellular space and the extracellular space.; Electrolytes in body fluids are active chemicals or cations that carry positive charges and anions that carry negative charges.
Fluid and Electrolyte Imbalance Flashcards
D) Keep client on complete bed rest. A) Monitor fluid intake and output. A 25-year-old client is admitted to a healthcare facility with complaints of fever, vomiting, and watery diarrhea for 2 days. On examination, the client has dry skin, delayed skin turgor, and hypotension.
Electrolyte Imbalance: Types, Symptoms, Causes & Treatment
Electrolyte Imbalance. An electrolyte imbalance occurs when certain mineral levels in your blood get too high or too low. Symptoms of an electrolyte imbalance vary depending on the severity and electrolyte type, including weakness and muscle spasms. A blood test called an electrolyte panel checks levels. Contents Overview Possible Causes Care ...
Fluid and Electrolyte Imbalance
2. Fluid and electrolyte balance is a dynamic process that is crucial for life. Potential and actual disorders of fluid and electrolyte balance occur in every setting, with every disorder, and with a variety of changes that affect well people (e.g., increased fluid and sodium loss with strenuous exercise and high environmental temperature ...
Chapter 15 Fluids and Electrolytes
The human body maintains a delicate balance of fluids and electrolytes to help ensure proper functioning and homeostasis. When fluids or electrolytes become imbalanced, individuals are at risk for organ system dysfunction. If an imbalance goes undetected and is left untreated, organ systems cannot function properly and ultimately death will occur. Nurses must be able to recognize subtle ...
Electrolyte Imbalances: What Is It, Causes, Presentation, and More
What causes electrolyte imbalances? Electrolyte imbalances are caused by different conditions and medications that intervene with the body's natural fluid balance.. Sodium Hyponatremia is considered the most common electrolyte imbalance.It can be caused by the decrease of the circulating blood volume, as seen in congestive heart failure and hepatic cirrhosis.
26.3 Electrolyte Balance
Fluid, Electrolyte, and Acid-Base Balance. 26.0 Introduction. 26.1 Body Fluids and Fluid Compartments. 26.2 Water Balance. 26.3 Electrolyte Balance. ... A relative decrease in blood sodium can occur because of an imbalance of sodium in one of the body's other fluid compartments, like IF, or from a dilution of sodium due to water retention ...
Fluid and Electrolyte Balance
You have electrolytes in your blood, urine (pee), tissues, and other body fluids. Electrolytes are important because they help: Balance the amount of water in your body. Balance your body's acid/base (pH) level. Move nutrients into your cells. Move wastes out of your cells. Support your muscle and nerve function.
Fluid and Electrolyte Imbalances: Interpretation and Assessm ...
Abstract. Maintaining the balance of fluid and electrolytes is crucial to the care of patients across the continuum. To do this, a practitioner must be cognizant of key monitoring and assessment parameters. Key electrolytes, their function within the body, normal values, signs and symptoms of imbalances, key treatment modalities, and other ...
Imbalances in Fluids and Electrolytes, Acids and Bases: An ...
Fluid balance is essential in maintaining appropriate blood volume. Electrolyte balance is one of the key issues in maintaining homeostasis in the body. It also plays a critical role in protecting cellular function, tissue perfusion, and acid-base balance. Most electrolyte imbalances include hypo and hyper states of sodium, potassium, calcium ...
Fluid and Electrolyte Imbalance
Fluid and Electrolyte Imbalance Electrolytes Ions that create electricity or energy to help our body maintain normal functioning (mainly in muscles, nerves, heart and brain). ElectroLYTES - they LIGHT up the cells with energy. They help us to maintain fluid balances because WHERE FLUIDS FLOW THE ELECTROLYTES GO!. As they are related to fluid, energy, and lighting up cells they can remembered ...
PDF Care for patients with fluid and electrolytes imbalance
and treatments, can disrupt a patient's fluid and electrolyte balance. Even a patient with a minor illness is at risk for fluid and electrolyte imbalance. Fluid Volume Deficit (Hypovolemia) Fluid Volume Excess (Hypervolemia) The body loses water all the time. A person responds to the thirst reflex by drinking fluids and eating foods that contain
Fluid and Electrolyte Imbalances: Interpretation and Assessment
Maintaining the balance of fluid and electrolytes is crucial to the care of patients across the continuum. To do this, a practitioner must be cognizant of key monitoring and assessment parameters. Key electrolytes, their function within the body, normal values, signs and symptoms of imbalances, key treatment modalities, and other considerations ...
Fluid and electrolyte imbalance and management
Seminar On Fluid and Electrolyte Imbalance Raksha Yadav 1st Year M.Sc. Nursing AIIMS Rishikesh. 2. INTRODUCTION. 3. HOMEOSTASIS. 4. Water content of the body. 5. Body fluids are distributed in two distinct area: intracellular fluid (ICF) 40% body weight Extracellular fluid (ECF) 20% body weight Interstitial fluid - 15% body weight Plasma -5% ...
Fluid and Eletrolyte imbalance and nursing care.
Fluid and Eletrolyte imbalance and nursing care. Sep 9, 2020 •. 5 likes • 539 views. V4Veeru25. common sign symptoms , causes, management & nursing management of fluid & eletrolyte imbalance. Healthcare. 1 of 47. Fluid and Eletrolyte imbalance and nursing care. - Download as a PDF or view online for free.
Fluid and Electrolyte Balance
Fluid, Electrolyte, and Acid-Base Balance (chapter from open anatomy textbook) About Body Water (article from Merck Manual Patient Version) ... Nursing Care of Patients with Fluid, Electrolyte, and Acid-Base Imbalances (ebook chapter from Nursing Reference Center Plus) Electrolyte Disorders (Merck Manual for Professionals)
Fluid and Electrolyte Assignment
Fluid and Electrolyte Scenario. Electrolyte Imbalance. Patient Profile E. is a 73-year-old woman whose daughter brings her to see the health care provider because she has had a case of the "stomach flu," with vomiting and diarrhea for the past three to four days and is now experiencing occasional light-headedness and dizziness. Her past medical history includes hypertension ...
Fluid and Electrolyte Imbalance Flashcards
In ECF: the fluid between cells. An element or compound which will separate into an electrically charged ion. A solute in a solution moves from an area of higher concentration to lower concentration. (Ex. Gas exchange in the lungs) Movement of solvent across a semipermeable membrane from lower to higher concentration.
Fluid and electrolyte imbalance
Fluid and electrolyte imbalance. 1. 2. Fluid and electrolyte balance is a dynamic process that is crucial for life It plays an important role in homeostis Imbalance may result from many factors, and it is associated with the illness. 3. TOTAL BODY FLUID 60% OF BODY wt Intracellular fluids Extracellular fluids Interstitial Trancellular ...
PDF Chapter 27 Fluid, Electrolyte, and Acid Base Balance
Most common problems with electrolyte balance are caused by imbalance between gains and losses of sodium ions 2. Problems with potassium balance are less common, but more dangerous than sodium imbalance 27-4 Electrolyte Balance Sodium Balance o Total amount of sodium in ECF represents a balance between two factors 1.
Fluid and Electrolyte Balance
Fluid and electrolyte balance is the regulation of fluids and electrolytes, or charged molecules known as ions, to maintain a stable internal environment, known as homeostasis. Maintaining fluid and electrolyte homeostasis is essential for normal functioning of the body.
Fluid and electrolyte imbalance
4. INTRODUCTION Fluid and electrolyte imbalance commonly accompany illnesses. Severe imbalances may results in death. Such imbalances affect not only the acutely and chronically ill patients but also clients with faulty diets and those who take selected medications such as diuretics and gluccocorticoids preparations. So, every nurse must understand the process of fluid and electrolyte balance ...
Fluid and Electrolyte Imbalance
Fluid and Electrolyte Imbalance - Free download as PDF File (.pdf), Text File (.txt) or read online for free. It is a project regarding the fluid and electrolyte imbalance

Fluid and Electrolytes, Acid-Base Balance

Table of Contents

Body Fluids

Fluid and Electrolyte Transport

Acid-Base Balance

Medical Management

Nursing Management

10 thoughts on “Fluid and Electrolytes, Acid-Base Balance”

Leave a Comment Cancel reply

Nursing Fundamentals [Internet].

Chapter 15 Fluids and Electrolytes

15.2. BASIC FLUID AND ELECTROLYTE CONCEPTS

Body Fluids

Figure 15.1

Fluid Movement

Figure 15.2

Figure 15.3

Solute Movement

Figure 15.4

Figure 15.5

Fluid and Electrolyte Regulation

Figure 15.6

Figure 15.7

Fluid Imbalance

Excessive Fluid Volume

Deficient Fluid Volume

Video Review of Fluid and Electrolytes [ 19 ]

Isotonic Solutions

Figure 15.8

Hypotonic Solutions

Figure 15.9

Hypertonic Solutions

Figure 15.10

Figure 15.11

Figure 15.12

Video Review of Fluids and Electrolytes: Sodium [ 6 ]

Figure 15.13

View helpful mnemonics for hypokalemia at Hypokalemia NCLEX Review Notes.

Figure 15.14

View a video of a patient exhibiting Chvostek’s Sign and Trousseau’s Signs of hypocalcemia.

15.5. ACID-BASE BALANCE

Arterial Blood Gases

Read more information about interpreting ABG results in the “ Oxygen Therapy ” chapter in Open RN Nursing Skills .

Table 15.5a

Video Review of Acid-Base Balance [ 3 ]

Interpreting Arterial Blood Gases

Review of Tic-Tac-Toe Method of ABG Interpretation [ 4 ]

Respiratory Acidosis

Read more details about oxygenation equipment in “ Oxygen Therapy ” in Open RN Nursing Skills .

Breathing Retraining

Metabolic Acidosis

Metabolic Alkalosis

Analyzing ABG Results

Table 15.5b

15.6. APPLYING THE NURSING PROCESS

Subjective Assessment

Objective Assessment

Figure 15.15

Table 15.6a

Review additional details about assessing these body systems in Open RN Nursing Skills .

Figure 15.16

Table 15.6b

Life Span Considerations

NEWBORNS AND INFANTS

CHILDREN AND ADOLESCENTS

OLDER ADULTS

Table 15.6c

Excess Fluid Volume Example

Deficient Fluid Volume Example

Risk for Imbalanced Fluid Volume Example

Risk for Electrolyte Imbalance Example

Outcome Identification

Planning Interventions

Table 15.6d

Implement Interventions Safely

Table 15.6e

15.7. PUTTING IT ALL TOGETHER

Applying the Nursing Process

5.8. LEARNING ACTIVITIES

Figure 15.17