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LPN IV Series: Homeostasis and Regulatory Functions Relationship to IV Therapy

3 Contact Hours
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This peer reviewed course is applicable for the following professions:
Licensed Practical Nurse (LPN), Licensed Vocational Nurses (LVN)
This course will be updated or discontinued on or before Friday, March 7, 2025

Nationally Accredited

CEUFast, Inc. is accredited as a provider of nursing continuing professional development by the American Nurses Credentialing Center's Commission on Accreditation. ANCC Provider number #P0274.

This course does not meet the Florida LPN IV Certification requirement.

≥ 92% of participants will know what symptoms electrolyte imbalances produce.


After completing this continuing education course, the participant will be able to meet the following objectives:

  1. Elaborate on the importance of homeostasis.
  2. Review water intake and excretion.
  3. Outline the types of dehydration.
  4. Identify the function of electrolytes.
  5. Summarize symptoms of electrolyte imbalances.
  6. Analyze the use of isotonic, hypotonic, and hypertonic fluids.
CEUFast Inc. and the course planners for this educational activity do not have any relevant financial relationship(s) to disclose with ineligible companies whose primary business is producing, marketing, selling, re-selling, or distributing healthcare products used by or on patients.

Last Updated:
To earn of certificate of completion you have one of two options:
  1. Take test and pass with a score of at least 80%
  2. Reflect on practice impact by completing self-reflection, self-assessment and course evaluation.
    (NOTE: Some approval agencies and organizations require you to take a test and self reflection is NOT an option.)
Authors:    Desiree Reinken (MSN, APRN, NP-C) , Julia Tortorice (RN, MBA, MSN, NEA-BC, CPHQ)


Our bodies maintain equilibrium through many processes. One of these processes involves homeostasis, which will be discussed in detail. Electrolytes also have a crucial role in our body by ensuring our levels are balanced, and our cells, nerves, and muscles function as they should. Many of these electrolytes and what can happen if they are not balanced will be discussed. One way to ensure we are hydrated and keep our bodies in check is hydration. When hydration is limited, we can replenish through intravenous (IV) fluids. We must use the correct fluid type based on the patient's need and condition.


Homeostasis is the steady state of the body by which the body's internal systems maintain a balance. It is maintained by adaptive responses that promote healthy functioning of the body.

One of the primary objectives of IV therapy is to maintain or restore the fluid and electrolyte balance in the body. Our bodies are composed mainly of fluid. These fluids will account for about 60% of the total body weight in an adult male and 45-50% in an adult woman. In infants, fluids account for about 80% of the total body weight and will steadily decrease throughout childhood until it reaches adult percentages at around eight years old.

Body fluids are composed of water and solutes. Solutes are classified as either electrolytes or nonelectrolytes. The nonelectrolytes are solutes without an electrical charge, including glucose, proteins, lipids, oxygen, carbon dioxide, and organic acids. The electrolytes will be discussed later.

Fluids help:

  • regulate the body's temperature
  • transport nutrients and gases throughout the body
  • carry cellular waste products to excretion sites

The body fluids are distributed between two major compartments: intracellular fluid (ICF) inside the cells and extracellular fluid (ECF) outside the cells.

The ECF occurs in two forms: interstitial fluid surrounding each cell and lymph gland: and intravascular fluid, which is blood plasma. The interstitial fluid comprises the cerebrospinal, pleural, peritoneal, or synovial fluids and the secretions from the salivary glands, pancreas, liver, and sweat glands. The distribution of fluids between these two compartments is constant when the body is healthy. The heart, kidneys, liver, adrenal and pituitary glands, and nervous system all play a part in maintaining fluid balance in the body.

Fluid accumulation in a compartment other than the intracellular or extracellular space is third-space fluid shifting. The accumulation happens when a cellular membrane allows water and fluid to enter but not exit. For example, fluids pool in a burn site with severe burns, causing depletion of the ICF and ECF. If pancreatitis fluids "leak out" into the peritoneal cavity, this causes depletion of the ICF and ECF. Patients undergoing long and extensive surgeries will collect third-space fluids and become intravascularly depleted despite administering large volumes of IV fluids and blood. Third-space fluid shifting can also occur due to acute bowel obstruction, ascites, and sepsis. These patients will experience tachycardia, hypotension, weight gain, low urine output, poor skin turgor, and hyponatremia.

Fluid balance is also affected by the following:

  • fluid volume
  • distribution of fluids in the body
  • the concentration of solutes in the fluid

The distribution of fluids depends on the hydrostatic and colloid osmotic pressures in the capillaries. Fluid volumes and concentration are regulated by interacting with two hormones, antidiuretic hormone (ADH) and aldosterone.

ADH is secreted when plasma osmolarity increases or circulating blood volume decreases, and blood pressure drops. ADH restores blood volume by reducing diuresis and increasing water retention.

Aldosterone is secreted when the serum sodium level is low, the potassium level is high, or the circulation volume of fluid decreases. It causes the kidneys to retain sodium and water.

Osmolarity is the concentration of a solution. Usually, the serum has the same osmolarity as other body fluids, approximately 300 mOsm/L. If your patient has a lower serum osmolarity, they may have a fluid overload. A higher serum osmolarity indicates the patient may be experiencing hemoconcentration of the fluid and dehydration.

Body fluids are in constant motion moving between the fluid compartments through membranes. Homeostasis is maintained when the solutes and fluids are distributed evenly on each membrane. When there is an imbalance, these molecules will move between the compartments by various routes, including:

  • In diffusion, molecules move from areas of higher concentration to areas of lower concentration.
  • Active transport requires energy for molecules to move from areas of lower concentration to areas of higher concentration. These molecules are moved by physiologic pumps (sodium-potassium pumps).
  • With passive transport, solutes are affected by the electrical potential across cell membranes.
  • Filtration is the movement of substances from an area of high hydrostatic pressure to an area of lower hydrostatic pressure.
  • Capillary filtration forces fluid and solutes through capillary wall pores.
  • Osmosis fluids flow passively from an area of higher water concentration to an area of lower concentration. The process stops when the solute concentrations on both sides of the membrane are equal. The body responds to osmolality changes because of osmotic and hydrostatic pressures (Nettina, 2019).

As discussed above, fluid is essential for our body. It has many different functions, our body depends on it, and the actions of fluid depend on our intake and excretion.

Water Intake and Excretion

Water intake and output are essential for homeostasis. In fact, water makes up nearly two-thirds of our weight. Women tend to have lower amounts of water body weight than men. Patients who are older and obese also have lower percentages of water body weight.

One must consume water to balance water loss in the body. Not only does water intake prevent dehydration, but it also prevents kidney stones and many other medical diagnoses. A healthy adult should drink around two liters of fluids daily. In most circumstances, drinking more fluid is considered better than drinking less. The body is better at getting rid of excess water than conserving water when it has too little (Lewis, 2022a).

The body can absorb water from the digestive tract. The body loses water via the kidneys through urination. Depending on intake and how well the kidneys function, they may excrete up to 10 gallons of urine daily. Around a liter of water is naturally lost through the skin and the lungs. Increased water loss can occur when patients exercise outside in hot temperatures where excess sweating will occur.

Other ways increased water loss is seen is through vomiting and diarrhea. When gastrointestinal upset is severe or prolonged, increased water loss will occur. Patients may be unable to compensate for this water loss as they may not feel their stomachs can tolerate intake. Patients who have altered mental status or restricted mobility are at risk of a lack of water or fluid intake.

Electrolytes and water play crucial roles, often together, in the body. Electrolytes dissolve in the water that is in the body. The body deploys several mechanisms to ensure fluid balance and electrolytes remain in good standing. Maintaining water balance can occur through thirst signaling, osmosis, and the kidneys and pituitary glands. When the body lacks fluid, nerves in the brain are stimulated, creating the sensation of thirst. As fluid volume decreases, the sensation of thirst only grows stronger.

When water volume is low, the pituitary gland secretes an ADH called vasopressin; this stimulates the kidneys to conserve the water already in the body, which results in less urine output. The opposite occurs when the body has too much water. Only small amounts of vasopressin are released, so the kidneys continue to expel water through urination.

With osmosis, water flows from different areas of the body; this means that where there is excess water, osmosis can shift this water to areas with small amounts of water volume (Lewis, 2022a).

Specific conditions and circumstances place patients at risk of fluid volume disorders. They include:

  • Chronic kidney disease and kidney failure- patients are not able to rid the body of excess fluid.
  • Heart failure- a fluid buildup will occur in the tissues, lungs, and liver.
  • Increased swelling and fluid retention often occur after surgery.
  • Medications, such as diuretics, can cause too much fluid to leave the body.
  • Severe vomiting and diarrhea.
  • Extreme blood loss. 
  •  Fever. 
  • Lack of ADH in the body (Kreimeier, 2000; MedlinePlus, n.d.).

When our water intake and excretion are not balanced, or our bodies and organs are not performing as they should, fluid volume overload can occur.

Volume Overload

Fluid volume overload occurs when too much water is in the body and circulatory system. The excess fluid in the body causes the heart to work harder and, in severe cases, can cause heart failure. Fluid volume overload can also cause pulmonary edema, leading to shortness of breath. Excess fluid buildup can occur over a short period of time, or it can occur over a longer period of time. On top of potential heart failure and shortness of breath, patients may experience high blood pressure and pitting edema in the legs if fluid volume buildup is a chronic issue (Hansen, 2021).

Fluid volume overload can occur for various reasons. At times, it can be due to the infusion of fluids, such as when the patient requires any infusion via an IV line. Fluid volume overload can also occur through the delivery of nutrition, such as with total parenteral nutrition (TPN). The risk of overload increases for elderly patients and those with heart or kidney failure. These same effects can be seen when someone intakes too much sodium. The body will naturally retain water to counteract the effects of excess sodium in the body.

Patients with these conditions are at an increased risk of fluid volume overload, and their conditions may produce symptoms that are similar to fluid volume overload. They include:

  • Kidney disease
  • Thyroid problems
  • Liver damage/disease
  • Circulatory issues, especially lymphatic circulatory problems
  • Heart damage, such as pericarditis
  • Lung problems, such as asthma (Hansen, 2021; Cirino, 2017)

It is evident that the body needs water to function correctly. When the body has excess amounts of water or water intake is deficient, symptoms and further problems will result.


Dehydration can affect patients of all ages. Dehydration can cause significant issues and make other diagnoses and conditions worse. Reviewing the patient's medical history can give a first-hand view of the causes of dehydration, such as medications, fluid loss, exercise, exposure, and illness. It can be diagnosed by laboratory testing and physical examination. To combat dehydration, patients can be given a fluid replacement.

Common symptoms of dehydration include thirst, fainting or syncope, fatigue, palpitations, dizziness, hypotension, primarily upon standing, muscle cramps, dry skin, headaches, and lightheadedness. Upon reviewing vital signs, patients with dehydration may experience low blood pressure, fever, fast breathing, and fast heart rate. Some symptoms are easily masked. For example, a rapid heart rate may not be seen if patients take beta blockers. Physical exams may reveal other signs, such as cracked lips, delayed capillary refill, and skin tenting.

There are different ways in which dehydration can be diagnosed, though there is no gold standard. Checking weight may reveal weight loss. Other tests that should be reviewed include urine specific gravity, blood urea nitrogen (BUN), and creatinine (Taylor & Jones, 2022).

Types of Dehydration

Specific types of dehydration are commonly seen and should be reviewed.

Hypotonic/Hyponatremic: Hypotonic or hyponatremic dehydration occurs when sodium loss exceeds water loss, decreasing serum osmolality. The cells fill or swell, and cerebral edema may occur. Hypotonic/hyponatremic dehydration can be acute or chronic. Hypotonic/hyponatremic dehydration is considered chronic after 48 hours. Though the body may try to adapt to this type of dehydration, symptoms often occur. Symptoms include headaches, confusion, nausea and vomiting, fatigue, coma, and even death.

Causes of hypotonic/hyponatremic dehydration include the following:

  • Addison's disease
  • Cystic fibrosis
  • Diuretics
  • Renal tubular acidosis
  • Iatrogenic causes such as hypotonic fluids used for hydration

Laboratory values often seen in hypotonic/hyponatremia dehydration include a decrease in urine sodium excretion and a decrease in urine specific gravity (Rondon & Badireddy, 2022).

Hypertonic/Hypernatremic: Hypertonic or hypernatremic dehydration occurs when water excretion from the body exceeds sodium excretion.

There are many causes of hypertonic/hypernatremic dehydration. Common causes include the following:

  • End-stage renal disease
  • Excess sweating
  • Fever as it increases the respiratory rate and water loss
  • Decreased water intake
  • Drinking seawater
  • Polyuria or increased urination also increases water loss; this is commonly seen with diuretic use and diabetes

Laboratory values often seen in hypertonic/hypernatremia dehydration include increased serum osmolality and serum sodium. Urine specific gravity will be high (Tiarks, n.d.).

Isotonic/Isonatremic: Isotonic or isonatremic dehydration occurs where sodium and water are lost.

There are many causes of isotonic/isonatremic dehydration, and they include:

  • Excessive sweating during exercise or hot/humid weather
  • Severe vomiting and diarrhea, often seen in chemotherapy, and gastrointestinal upset

If not corrected, isotonic/isonatremic dehydration can cause kidney injury.

With laboratory testing, urine volume will be decreased and will have an increased specific gravity (Taylor & Jones, 2022).

IV Fluids

Just as there are types of dehydration, there are different types of IV fluids often used to replenish a loss.

Three basic types of fluids are utilized for IV therapy. They are:

  1. Isotonic
  2. Hypotonic
  3. Hypertonic

Isotonic fluids have the same osmolality as serum and other body fluids (Nettina, 2019). It expands the intravascular compartment. It can treat hypotension secondary to hypovolemia or as maintenance fluids.

Isotonic fluids include:

  • 2.5% dextrose/0.45% sodium chloride
  • 0.9% sodium chloride (normal saline)
  • 5% dextrose and water
  • Normosol® R
  • Plasmalyte® A
  • Plasmalyte® R
  • lsolyte® 4 E · Ringer's
  • Lactated Ringer's
  • 2.5% dextrose in 1/2 lactated Ringer's
  • 6% dextran and 0.9% sodium chloride
  • 10% dextran and 0.9% sodium chloride

Hypotonic fluids have a lower osmolality than the serum (Nettina, 2019). When given, they help hydrate the cells and can decrease the amount of fluid in the circulatory system. Hypotonic fluids are used when diuretic therapy dehydrates the cells to lower serum sodium levels, treat diabetic ketoacidosis, and treat hyperglycemic nonketotic syndrome.

Hypotonic fluids include:

  • 0.45% normal saline (half-normal saline)
  • 0.33% normal saline (one-third saline)
  • D2.5W (dextrose 2.5% in water)

Hypertonic solutions have a higher osmolality than the serum (Nettina, 2019). These fluids pull fluid back into the blood vessels from the interstitial and intracellular compartments. It can treat hypovolemia and low serum sodium levels or help reduce the risk of edema and low blood pressure in postoperative patients.

Hypertonic fluids include:

  • 5% dextrose/0.2% sodium chloride
  • 5% dextrose/0.3% sodium chloride
  • 5% dextrose/0.45% sodium chloride
  • 5% dextrose/0.9% sodium chloride
  • 10% dextrose/0.2% sodium chloride
  • 10% dextrose/0.45% sodium chloride
  • 10% dextrose/0.9% sodium chloride
  • 3% sodium chloride
  • 5% sodium chloride
  • 10% dextrose and water
  • 50% dextrose and water
  • 5% dextrose in Ringer's
  • 5% dextrose in lactated Ringer's
  • 5% dextrose and 5% alcohol
  • 5% sodium bicarbonate injection
  • 10%, 15%, and 20% mannitol injection
  • 6% dextran and 0.9% sodium chloride
  • 10% dextran and 0.9% sodium chloride


Electrolytes help to keep our bodies functioning properly. Electrolytes help our muscles contract and assist with chemical reactions like fluid balance. Electrolytes can be either positive or negative; they can conduct electricity when dissolved in a liquid. For example, sodium and chlorine are oppositely charged, and when together, they even each other out.

Electrically-charged ions are positive ions or cations, and negative ions are called anions.

Electrolytes help to maintain homeostasis and balance within the body. Our bodies use ions and electrolytes to help move chemical compounds between cells (Cleveland Clinic, 2021).


The body needs large amounts of sodium. We obtain sodium through the intake of food and drinks, and we lose sodium through urination and sweating. When intake and loss of sodium are not equal, problems arise.

Most of the sodium in the body is centered in and around the cells. Sodium assists with the function of our nerves and muscles. Luckily, our body is aware of when sodium imbalances occur. When sodium levels are high, the heart, kidneys, and blood vessels take action. The kidneys begin to excrete more sodium, balancing out the levels again. When sodium levels are low in the body, other areas of the body sense it. The pituitary gland and the kidneys work to conserve or retain sodium.

Unfortunately, as we age, our bodies can lose the ability to maintain fluid and sodium balance; this is because of the following:

  • Medications- many medications for diabetes, heart failure, and high blood pressure cause the body to excrete more fluid and sodium.
  • Lack of water intake- this can be due to decreased thirst because of age or diseases such as dementia, where patients may not realize they are thirsty.
  • Less fluid in the body- naturally, as we age, we lose fluid content in our body.


Potassium is essential for our cells, muscles, and nerves and is primarily located in our cells. Our body stores large amounts of potassium in our cells to help maintain the level in the blood. It aims to match the potassium level in the body by what is being excreted.

We get potassium from the food and drink we intake, and we excrete potassium in our urine and a little bit of our sweat.

Some medications can affect our storage and excretion of potassium (Lewis, 2022g).


Chloride helps to regulate fluid and nutrients that go in and out of the cells, stimulates digestive stomach acid, and maintains pH in the body. Chloride is absorbed in the small intestines and is excreted in the urine. Chloride and sodium are bound together, so the levels are usually similar. If one is low, so is the other (Berend et al., 2012).


Nearly all calcium is stored in our bones, but our cells can contain and use calcium. Calcium has so many roles in our body, including:

  • Bone and teeth formation
  • Maintaining normal heart rhythm
  • Blood clotting
  • Muscle contraction
  • Enzyme function

Our bodies can control calcium levels in our blood and cells. Depending on where it is needed, the body moves calcium around. If not enough calcium is consumed, the body moves calcium out of the bones to where it is needed; this movement can weaken bones causing osteoporosis. We should all aim to consume at least 1,000 to 1,500 milligrams of calcium daily.

Calcium is regulated by calcitonin and the parathyroid hormone. The parathyroid hormone is in the parathyroid gland, which is located near the thyroid. When calcium levels are low, the parathyroid gland produces extra parathyroid hormone. The opposite is true when there is excess calcium.

The parathyroid hormone acts in the following ways:

  • Encourages the kidneys to activate vitamin D, causing the digestive tract to absorb calcium.
  • Encourages the bones to release calcium.
  • Encourages the kidneys to keep calcium and not excrete it in the urine. 

The thyroid gland produces calcitonin, which lowers calcium levels by slowing the breakdown of the bone (Lewis, 2022e).


Phosphorus is an electrolyte in the body, primarily found in the bone. The rest of the body's phosphorus is found inside cells and used as an energy source. Phosphorus is necessary for bone and teeth formation.

The intake of food is our primary source of phosphorous. Phosphorous is excreted in our urine and stool.

Foods high in phosphorous include soft drinks, milk, chocolate, and egg yolks (Qadeer & Bashir, 2022).


Magnesium is an important electrolyte for our body and our bones. In fact, half of the magnesium in our bodies is in our bones. Magnesium is crucial for muscle and nerve function and the formation of teeth and bones. Magnesium also helps with the metabolism of potassium and calcium. The body's magnesium level depends on how we obtain it, such as from food. Magnesium is excreted in urine and feces (Lewis, 2022f).

ElectrolyteNormal ValuePrincipal FunctionsSigns of Imbalance
  • Major cation in ECF
135-145 mEq/L
  • Maintains ECF osmolarity
  • Helps maintain blood pressure
  • Influences water distribution
  • Helps regulate acid-base balance
  • Aids nerve/muscle fiber impulse transmission
  • Hypernatremia: Irritability, thirst, fever, decreased urine output, flushed skin, hypertension
  • Hyponatremia: Irritability, fatigue, muscle weakness, tachycardia, headache, hypotension, increased urine output
  • Major cation in ICF
3.5-5.0 mEq/L
  • Maintains fluid balance in cells
  • Maintains cell osmolarity
  • Contracts skeletal, cardiac, and smooth muscles
  • Major role is acid-base balance
  • Promotes cell growth
  • Hyperkalemia: muscle weakness, nausea, diarrhea, lethargy, bradycardia, hypotension, cardiac arrhythmias
  • Hypokalemia: fatigue, weakness, leg cramps, weak/irregular pulse, hypotension, hyperglycemia, bradycardia, cardiac arrhythmias
  • Major anion in ECF
96-106 mEq/L
  • Maintains serum osmolarity
  • Combines with major cations to create important compounds: sodium chloride, potassium chloride, calcium chloride
  • Hyperchloremia: stupor, rapid/ deep breathing, muscle weakness
  • Hypochloremia: increased muscle excitability, tetany, decreased respirations
  • 99% found in bones and teeth
8.9-10.1 mg/dL
  • Enhances bone strength
  • Maintains muscle tone
  • Maintains cell membrane structure, function, permeability
  • Enzyme co-factor for clotting
  • Affects the activation, excitation, and contraction of cardiac and skeletal muscles
  • Hypercalcemia: anorexia, nausea, fatigue, constipation, dehydration, headache, hypertension, cardiac arrhythmias
  • Hypocalcemia: muscle spasms or cramping in calf muscles, tetany, positive Chvostek or Trousseau sign, hyperreflexia, laryngospasm, cardiac arrhythmias
  • Major anion in ICF
2.5-4.5 mg/dL
  • Maintains cell integrity
  • Maintains bones/teeth
  • Major role in acid-base balance as a urinary buffer
  • Essential to muscle, red blood cell, and neurologic functions
  • Hyperphosphatemia: anorexia, nausea, tetany, tingling, cramps, nervousness, cardiac arrhythmias
  • Hypophosphatemia: lethargy, stuttering/stammering, joint stiffness, memory loss, muscle pain
  • Major cation in ICF
1.5-2.5 mg/dL
  • Active in carbohydrate and protein metabolism
  • Facilitates sodium and potassium movement across all membranes
  • Influences calcium levels
  • Affects muscular irritability and contractions
  • Hypermagnesemia: muscle weakness, lethargy, nausea, hypotension, slow/weak pulse, bradycardia, decreased level of consciousness.
  • Hypomagnesemia: dizziness, confusion, leg cramps, nausea, difficulty swallowing, cardiac arrhythmias
(Nettina, 2019)

These are the primary or common electrolytes found in the body and cells. Now, let's discuss what happens when these electrolytes have an imbalance.

Electrolyte Imbalances

As we learned above, electrolytes play critical roles in the body. Electrolyte imbalances occur when the level of electrolytes in the body is not within their specified ranges. Any imbalance can create significant issues for the patient, including life-threatening symptoms.

Hypernatremia: Hypernatremia means there are excess amounts of sodium in the body. Severe volume loss and depletion can cause hypernatremia. However, the most common cause of hypernatremia is osmotic diuresis, often seen in patients diagnosed with diabetes. Patients with kidney disease are at risk of hypernatremia if the kidneys cannot concentrate the urine.

Patients with hypernatremia will experience thirst. However, extreme symptoms of hypernatremia are possible, depending on the extent of the condition. Adults may experience confusion, seizures, comas, hyperreflexia, and muscle excitability. Children may experience brain bleeds and thrombotic events (Lewis, 2022c).

Hyponatremia: Hyponatremia occurs when there is a lack of sodium in the body. At times, low sodium can be caused by an excess of other substances in the body, such as glucose or sugar. Patients with hyponatremia will experience central nervous system dysfunction. Older adults tend to experience more symptoms than younger adults. Altered mental status, altered personality, coma, seizures, muscle hyperexcitability, and even death can occur (Lewis, 2022d).

Hyperkalemia: Hyperkalemia occurs when the body has high amounts of potassium. Potassium is often found in many of the foods we eat and supplements we take. Even though potassium is helpful and necessary for our bodies, having too much potassium is very dangerous for the heart.

The most common causes of high potassium include the following:

  • Kidney damage and disease: One of the jobs of the kidney is to balance potassium levels between intake, such as food, and output with urination. When severely damaged or diseased, the kidneys cannot remove potassium, leading to excess buildup. The most common cause of hyperkalemia is chronic and advanced kidney disease.
  • Other causes of hyperkalemia include overeating food high in potassium, such as bananas, orange juice, cantaloupe, and honeydew melon. Medications can also cause high potassium in the body. Some medications prevent the kidneys from removing potassium.

Mild symptoms of hyperkalemia include tingling, nausea, muscle weakness, and paresthesia. These symptoms can be mild to severe and can progress. If severe, hyperkalemia can progress into problems such as arrhythmias and heart attacks (Simon et al., 2022).

Hypokalemia: Hypokalemia is the opposite of hyperkalemia and occurs when the body has a low potassium level, less than 3.5 mEq/L. Anything less than 2.5 mEq/L is considered to be severe and can be life-threatening. Hypokalemia usually occurs from a lack of potassium intake, a shift of potassium in the body to inside the cells, and increased potassium excretion.

Symptoms of hypokalemia include the following:

  • Worsening diabetes
  • Polyuria
  • Weakness
  • Fatigue
  • Palpitations
  • Pain/muscle cramps
  • Depression
  • Delirium, psychosis, and/or hallucinations (Kim et al., 2023)

Hyperchloremia: Hyperchloremia occurs when there is excess chloride in the blood. A chloride imbalance can also cause dehydration as chloride helps to maintain fluid balance.

Patients may not experience symptoms until chloride levels are high for an extended period of time. When symptoms are experienced, they include the following:

  • High blood pressure
  • Seizures
  • Retention of fluid
  • Arrhythmias
  • Muscle twitches
  • Weakness
  • Confusion
  • Personality changes
  • Numbness and tingling (Cafasso, 2018)

Hypochloremia: Hypochloremia is when there is a low level of chloride in the blood, this would be a level lower than 97 mEq/L.

Kidney problems often cause chloride imbalances.

Chloride imbalances often do not show signs and symptoms unless they are extreme. When patients do experience symptoms, they usually experience:

  • Fluid loss
  • Dehydration
  • Diarrhea
  • Vomiting (Seladi-Schulman, 2018)

Hypercalcemia: Hypercalcemia occurs when there is excess calcium in the blood. It can be mild to severe and temporary or chronic. As discussed above, parathyroid hormone and calcitonin assist with controlling the level of calcium in the body. Vitamin D is also essential in maintaining adequate levels of calcium. Acute and temporary hypercalcemia may not produce symptoms. However, with long-term and severe hypercalcemia, patients often experience the following:

  • Fatigue
  • Constipation
  • Loss of appetite
  • Headaches
  • Bone pain
  • Gastrointestinal upset (Lewis, 2022b)

Hypocalcemia: Hypocalcemia results when there are low calcium levels in the blood, usually less than 8.8 mg/dL. There are many causes of hypocalcemia, including renal disease, hypoparathyroidism, and vitamin D deficiency.

Symptoms of hypocalcemia include:

  • Seizures
  • Paresthesia
  • Heart failure
  • Tetany (Fong & Khan, 2012)

Hyperphosphatemia: High phosphate levels in the blood are called hyperphosphatemia, and it is often a sign of kidney damage. High phosphate levels may not cause problems, but it can cause low calcium, which results in symptoms such as muscle pain and weak bones (Goyal & Jialal, 2022).

Hypophosphatemia: Hypophosphatemia occurs when there are low phosphate levels in the blood. Hypophosphatemia can be mild to severe and acute or long-term.

Long-term hypophosphatemia can include the following symptoms:

  • Seizures
  • Altered mental status
  • Muscle pain
  • Fatigue
  • Weakness
  • Irritability (Sharma et al., 2022)

Hypermagnesemia: Hypermagnesemia results when there are excess magnesium levels in the blood. It is uncommon to see; if seen, patients may experience nausea, vomiting, and headaches. Common causes of hypermagnesemia include the following:

  • Lithium intake
  • Addison's disease
  • Hypothyroidism
  • Depression
  • Familiar hypercalcemia (Cascella & Vaqar, 2022)

Hypomagnesemia: Hypomagnesemia is when there are low levels of magnesium in the body. It can be mild or severe and usually occurs with low calcium and potassium levels.

Symptoms of mild hypomagnesemia include:

  • Fatigue
  • Weakness
  • Tremors
  • Muscle spasms or cramps
  • Nystagmus or abnormal eye movements

Symptoms of severe hypomagnesemia include:

  • Arrhythmias
  • Seizures
  • Delirium (Ahmed & Mohammed, 2019)
Electrolyte Imbalances
ElectrolyteCauses of ImbalancesTreatment
  • High sodium intake
  • Not drinking enough fluids
  • Excessive fluid loss (fever, diarrhea)
  • Major burns
  • Osmotic diuretics
  • Diabetes insipidus
  • Diuretic therapy
  • Hydration
  • Treat underlying cause
  • Fluid overload (IV or by mouth)
  • Hyperglycemia
  • Syndrome of inappropriate antidiuretic hormone secretion
  • Heart failure
  • Aggressive diuretic therapy
  • Nasogastric tube suctioning
  • Vomiting
  • Diarrhea
  • Excessive sweating
  • Hypotonic solutions
  • Treat underlying cause
  • Administer hypertonic solutions (slowly)
  • Foods containing sodium
  • Acidosis
  • Renal failure
  • Trauma
  • Burns
  • Crush injury
  • Tumor lysis syndrome
  • Hemolysis
  • Hyponatremia
  • Loop diuretic
  • Kayexalate
  • IV Insulin
  • IV sodium bicarbonate
  • IV calcium gluconate
  • Limit potassium-containing foods
  • Dialysis
  • Diarrhea
  • Vomiting
  • Severe diaphoresis
  • Prolonged diuretic therapy
  • Gastric suctioning
  • Hepatic disease
  • Respiratory alkalosis
  • Potassium chloride infusion (slow)
  • Oral potassium chloride supplement
  • Foods high in potassium
  • Diarrhea
  • Hyperparathyroidism
  • Respiratory alkalosis
  • Hypernatremia
  • Treat underlying cause
  • Vomiting
  • Diarrhea
  • Sweating
  • Prolonged fever
  • Hyponatremia
  • Respiratory acidosis
  • Treat underlying cause
  • hyperparathyroidism
  • excessive intake of vitamin D or calcium-containing antacids
  • prolonged immobilization
  • malignancies
  • IV fluids followed by a loop diuretic
  • IV calcitonin
  • dialysis
  • Malignancies
  • Vitamin D deficiency
  • Alkalosis
  • Hypoparathyroidism
  • Pancreatitis
  • Medications (phenobarbital, Dilantin, Lasix)
  • Hyperphosphatemia
  • Hypomagnesemia
  • Malnutrition
  • IV calcium gluconate (slow)
  • Vitamin D if chronic
  • Acute/chronic renal failure
  • Large intake of vitamin D
  • Hypoparathyroidism
  • Excessive use of laxatives or enemas containing phosphate
  • Chemotherapy
  • Calcium supplements
  • Calcium-based phosphate binders (Tums)
  • Dialysis
  • Malabsorption
  • Respiratory alkalosis
  • Prolonged vomiting
  • Long-term alcohol abuse
  • Hyperparathyroidism
  • Phosphate-binding antacids
  • IV infusion of phosphate
  • Foods high in phosphorus
  • Oral supplements
  • Renal failure
  • Diabetes mellitus
  • Acute lymphocytic leukemia
  • Acute myeloid leukemia
  • Excessive amounts of magnesium-containing antacids (Tums, Maalox, Mylanta) or laxatives (Milk of Magnesia), severe preeclampsia (receiving IV magnesium)
  • Dialysis (renal failure)
  • Loop diuretics
  • Fluid bolus
  • IV calcium
  • Malabsorption (irritable bowel disease, bowel resection, gastric bypass)
  • An alcoholic patient going through withdrawal
  • Hypothyroidism
  • Hypoparathyroidism
  • Hypercalcemia
  • High-dose steroid use
  • Sepsis
  • Pancreatitis
  • Specific medications (amphotericin B, cisplatin, cyclosporine, tobramycin, gentamicin)
  • IV replacement (slow)
  • Oral supplements

Case Study

Sharon is a 60-year-old female who presented to the emergency department with shortness of breath for the past four days. Sharon has a history of high blood pressure, stage 3 chronic kidney disease, and diabetes. Sharon's son, Jeremy, is present and tells the nurse that his mom is always winded, no matter what she does. She even experiences shortness of breath while resting lately. Jeremy also tells the nurse that his mother has been extremely lethargic for the past two days. Also, Sharon has been experiencing severe cramping in both legs for the past few days. She requires nearly total assistance with daily and routine activities.

Sharon was in the hospital six weeks ago for her chronic kidney disease; since then, she has continued to experience further medical problems.

She has been on 1.5L of oxygen via nasal cannula since her discharge from the hospital. One week ago, her dose of Lasix was doubled as she is experiencing increased kidney problems and now heart trouble.

Sharon appears alert and oriented to person, place, and time with no neurological deficit. However, she is in respiratory distress. She relies on her accessory muscles to assist with breathing and has difficulty completing sentences without stopping for air. Her vital signs show tachycardia, tachypnea, hypotension, and hypoxia.

The nurse and provider of care decide labs should be drawn.

Serum potassium: 2.4 mEq/L

Magnesium 1.3 mEq/L

During her physical exam, her abdomen was soft and non-distended. Pulses in the lower extremity were diminished bilaterally to +1.

The physician makes the following impressions:

  • Acute hypoxic respiratory failure secondary to pulmonary edema
  • Congestive heart failure
  • Hypokalemia and hypomagnesemia secondary to diuretics (her Lasix)

Impairments include the following:

  • The patient is lethargic and has difficulty breathing on minimal exertion (appears winded at rest).
  • The patient exhibits a decrease in overall muscle strength.

Activity limitations include the following:

  • The patient is unable to ambulate due to weakness and fatigue.
  • The patient cannot complete a simple task due to fatigue and respiratory distress.

Based on the patient's subjective and objective findings, Sharon's cardiopulmonary complications and co-morbidities (kidney disease) have led to congestive heart failure, hypomagnesemia, and hypokalemia. The targeted interventions include replacing potassium via IV and monitoring for other possible electrolyte imbalances. The patient's diuretics should be monitored since they may lead to unwanted side effects. The goal is to make the patient euvolemic, and if the patient cannot do so with diuretics, a nephrologist should be consulted for possible hemodialysis. Upon discharge, the patient will need potassium supplements following her diuretic therapy. Labs will need to be rechecked in one week, and the patient should be referred to a heart failure specialist.

In one week, Sharon got her labs rechecked, and it was determined that her electrolyte levels were now within normal range. Sharon and the family know what symptoms to look for and to get labs checked frequently.


It is natural for our bodies to seek balance and homeostasis. Homeostasis is the steady state of the body. It is maintained by adaptive responses that promote healthy functioning of the body. Some of these adaptive processes occur when there is an imbalance of electrolytes or fluid.

Our bodies are made up of a lot of water and fluid. Fluids help regulate the body's temperature, transport nutrients and gases and carry cellular waste products to excretion sites. Fluid is very important and can easily be affected. Fluid balance is affected by fluid volume, the distribution of fluids in the body, and the concentration of solutes in the fluid.

One surefire way to ensure fluid balance in the body is by maintaining an adequate fluid intake. A healthy adult should drink around two liters of fluids daily. If the body is healthy and not diseased, water and fluid excretion occur through urination and natural losses. Fluid volume overload can happen if we drink too much or our body holds on to too much water. Losing too much fluid is called a fluid volume deficit, and patients can easily become dehydrated. Hypotonic or hyponatremic dehydration occurs when sodium loss exceeds water loss, decreasing serum osmolality. Hypertonic or hypernatremic dehydration occurs when water excretion from the body exceeds sodium excretion. Isotonic or isonatremic dehydration occurs when sodium and water are lost.

Just as important as fluid is electrolytes. Common electrolytes include sodium, potassium, magnesium, phosphate, and chloride. Each electrolyte imbalance has its own causes, symptoms, and interventions. For example, sodium helps to maintain blood pressure and acid-base balances. When patients experience gastrointestinal upset, such as excessive vomiting and diarrhea, sodium loss or hyponatremia can occur. With hyponatremia, patients may experience further symptoms of irritability, fatigue, muscle weakness, tachycardia, headache, and hypotension. To fix the sodium imbalance, we must treat this underlying problem. Patients with gastrointestinal upset may not feel like eating and drinking. Therefore, patients may need IV hydration. Nurses must be careful when administering IV hydration to patients with heart or kidney failure. As you can see, each imbalance is unique to the patient, and interventions or treatments depend on the underlying cause of the imbalance and the condition and status of the patient.

It is our job as nurses and providers of care to ensure we take adequate histories from the patient to determine what is truly going on. Patients may be working out in extreme temperatures or accidentally taking too many over-the-counter vitamins. Patients can sometimes forget to keep up with their intake, which is often seen in dementia and Alzheimer's. It can be easy to overlook an electrolyte or fluid imbalance until the patient is experiencing symptoms; sometimes, those symptoms can be severe or life-threatening.

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Implicit Bias Statement

CEUFast, Inc. is committed to furthering diversity, equity, and inclusion (DEI). While reflecting on this course content, CEUFast, Inc. would like you to consider your individual perspective and question your own biases. Remember, implicit bias is a form of bias that impacts our practice as healthcare professionals. Implicit bias occurs when we have automatic prejudices, judgments, and/or a general attitude towards a person or a group of people based on associated stereotypes we have formed over time. These automatic thoughts occur without our conscious knowledge and without our intentional desire to discriminate. The concern with implicit bias is that this can impact our actions and decisions with our workplace leadership, colleagues, and even our patients. While it is our universal goal to treat everyone equally, our implicit biases can influence our interactions, assessments, communication, prioritization, and decision-making concerning patients, which can ultimately adversely impact health outcomes. It is important to keep this in mind in order to intentionally work to self-identify our own risk areas where our implicit biases might influence our behaviors. Together, we can cease perpetuating stereotypes and remind each other to remain mindful to help avoid reacting according to biases that are contrary to our conscious beliefs and values.


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