Hypercalcemia Complications: what nurses need to know

Hypercalcemia Complications: what nurses need to know

Published: May 7, 2023

Last Updated: May 14, 2023

William Kelly, MSN, FNP-C

Author | Nurse Practitioner

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An image of IV magnesium sulfate with Magnesium in a ball with low levels with surrounding foods that are high in magnesium

Hypercalcemia is when the blood has high calcium levels, which can lead to deadly hypercalcemia complications. These complications can be severe and potentially life-threatening if not identified and managed promptly.

As healthcare professionals who may have to care for patients with hypercalcemia, nurses need to be aware of the potential complications associated with this condition.

In this article, we will discuss levels of hypercalcemia, causes, treatment, complications, and monitoring parameters that nurses need to know about.

Hypercalcemia: Nursing assessment, complications, and treatment, with image of blood vessel with high level of calcium

Normal Calcium Levels & Hypercalcemia

Normal calcium levels can range from 8.5 – 10.5 mg/dL.

Calcium Levels

  • Normal Levels: 8.5 – 10.5 mg/dL
  • Mild Hypercalcemia: 10.5 – 12 mg/dL
  • Moderate Hypercalcemia: 12 – 14 mg/dL
  • Severe Hypercalcemia: > 14 mg/dL
  • Ionized Hypercalcemia: > 5.4 mg/dL

Causes Of Hypocalcemia:

There are multiple causes of hypercalcemia, including:

An image of the thyroid and parathyroid glands

Primary Hyperparathyroidism

Primary hyperparathyroidism is the most common cause of hypercalcemia, accounting for about 80% of cases. It occurs when the parathyroid glands produce too much parathyroid hormone (PTH), increasing calcium levels in the blood.

The most common cause of this is a benign tumor called a parathyroid adenoma, which develops in one of the parathyroid glands. Other less common causes of primary hyperparathyroidism include parathyroid hyperplasia, parathyroid cancer, and inherited genetic disorders.

Vitamin D in a softgel

Malignancy

Some types of cancer, such as multiple myeloma, lung cancer, breast cancer, and kidney cancer, can cause hypercalcemia by releasing substances that increase calcium levels in the blood. 

A yellow sun with vitamin D in the middle

Excessive Vitamin D

Taking too much vitamin D supplements or having a disease that increases vitamin D levels in the body, such as sarcoidosis, can lead to hypercalcemia.

A vector graphic of a bed

Immobilization

Prolonged immobilization, such as when a patient is bed-bound, can cause hypercalcemia by increasing bone resorption and calcium release.

A bottle of medications that are prescription

Medications

Certain medications can cause high calcium levels, including:

  • Certain supplements in excess (Vitamin D, Calcium, Vitamin A)
  • Thiazide diuretics
  • Lithium
  • Theophylline toxicity
A strand of DNA

Other conditions

Other generic and acquired positions can lead to hypercalcemia complications, including hyperthyroidism, acromegaly, pheochromocytoma, adrenal insufficiency, and TPN.

The causes of hypercalcemia explained

Nursing Assessment Of Hypercalcemia

Symptoms

Hypercalcemia can cause a wide range of symptoms, most nonspecific. The severity and type of symptoms depend on the calcium level in the blood, the underlying cause of hypercalcemia, and how quickly the levels change.

  • Mild Hypercalcemia (10.5 – 12 mg/dL): Usually asymptoamtic
  • Moderate hypercalcemia (12 – 14 mg/dL): polyuria, polydipsia, anorexia, nausea, and constipation
  • Severe Hypercalcemia (> 14 mg/dL): worsened above symptoms, altered mental status, and even cardiac arrhythmias.

Common symptoms of hypercalcemia include:

A depiction of the small bowel, which is largely responsible for absorption of magnesium

GI side effects

Hypercalcemia can cause anorexia, constipation, nausea, and vomiting.

A battery symbol which is low

Weakness and Fatigue

Patients with hypercalcemia often feel tired and weak, just like with many other electrolyte abnormalities.

A bladder full of urine

Urinary Frequency

High calcium levels lead to decreased concentration ability of the kidneys and subsequent urinary frequency/dehydration. 

a picture of a bladder with bladder stone blocking the bladder neck

Kidney Stones

Chronic high calcium levels in the urine can lead to nephrolithiasis (kidney stones). 

graphic of a brain

Altered Mental Status

Hypercalcemia can affect the central nervous system, leading to cognitive impairment and even confusion, stupor, or coma.

a desaturated heart and yellow cardiac conductive tissue showing the SA node, AV node, and ventricles

S/S of arrhythmias

Hypercalcemia can affect the heart’s electrical conductivity, leading to arrhythmias, which may cause palpitations, chest pain, shortness of breath, dizziness, or syncope. This is generally not as common with hypercalcemia as with other electrolyte abnormalities. 

An illustration of the heart with the pulmonary and aortic vessels

Cardiac Calcifications

Chronic hypercalcemia can lead to the deposition of calcium in heart valves, coronary arteries, and the heart muscle itself. This can also lead to hypertension and heart failure. 

A muscle with red electric bolts indicating pain

Bone Pain

Bone pain can be a symptom of high calcium due to malignancy or primary hyperparathyroidism. 

PHYSICAL Assessment

When performing a physical exam for a patient suspected of having hypercalcemia, the nurse should assess for the following:

Vital Signs

  • HR: May be irregular (indicating an arrhythmia)
  • BP: May be increased
A face with the facial nerve present, which is causing Chvostek sign

Inspection

  • General: May appear weak or fatigued
An image of carpopedal spasms occurring with a blood pressure cuff inflated on the upper arm

Auscultation

  • Heart: May be irregular if arrhythmia present
  • Lungs: Clear to auscultation
a gloved hand palpating unspecified skin

Palpation

  • Abdomen: May have abdominal tenderness
  • Extremities: May have bone pain or tenderness, may have extremity weakness

Treatment for Hypercalcemia

The treatment of hypercalcemia depends on the severity of the condition and the underlying cause.

Assess the Patient

Ensure they don’t have any symptoms and are stable, including recent vital signs.

Cardiac Monitor

Make sure your patient is on the cardiac monitor. Obtain an ECG if it still needs to be done. 

Notify the Provider

Notify the provider of the calcium levels, your assessment, and their cardiac rhythm.

Ensure IV access

Make sure there is at least one IV site, but place a second line if the hypercalcemia is severe.

Administer Treatment

Administer medications and fluids that are ordered (discussed below).

Treatment for hypercalcemia:

An IV drip chamber with 1 drop (ggt) of fluid dripping down

General Measures

Mild hypercalcemia often does not require any specific calcium-lowering therapies, but instead can usually be managed by:

  • Treating any dehydration
  • Decreasing bed rest
  • Avoiding high-calcium diets
  • Avoiding medications that increase calcium levels
    • Thiazide Diuretics
    • Lithium 
    • Calcium supplements
    • Vitamin D supplements
Bag of IV magnesium sulfate

Isotonic Fluids

Patients who have moderate to severe hypercalcemia often are volume depleted. This helps to correct the hypovolemia and increase calciume excretion in the urine. 

NS or LR given at 200-300ml/hr and then adjusted to a urine output of 100-150ml/hr is recommended for 24-48 hours until the volume depletion is corrected. 

What about Lasix?

Loop diuretics aren’t traditionally recommended, however, patients with heart or kidney failure may benefit/require loop diuretics in addition to fluid.

Calcium

Calcitonin

Calcitonin is a hormone that can lower calcium levels in the blood by decreasing bone resorption. This is usually reserved for severe hypercalcemia with neurologic symptoms like decreased mental status. 

The recommended dose is 4 units/kg SQ or IM every 12 hours for 24-48 hours. 

Vitamin D softgels

Bisphosphanates

These medications can reduce bone resorption and lower calcium levels in the blood. Bisphosphonates are used for longer-term control of hypercalcemia, especially when related to malignancy. 

If given IV for severe hypercalcemia in the hospital, Zalendronic acid is recommended 4mg IV over 15 minutes. This can be repeated in 7 days if needed.

Vitamin D softgels

Denosumab (prolia)

Denosumab is a monoclonal antibody that is sometimes used if Bisphosphonates are not effective or not able to be used. There is a higher risk of hypocalcemia occurring with this medication, so it is avoided when possible.

Bag of IV magnesium sulfate

Glucocorticoids

This is primarily only given if the hypercalcemia is caused by lymphoma, sarcoidosis, or other granulomatous disease that increases calcitriol production and subsequently increases calcium absorption. 

Bag of IV magnesium sulfate

Dialysis

In severe cases, dialysis may be needed to remove excess calcium from the blood, especially if they also have heart failure or severe renal failure.

Bag of IV magnesium sulfate

Treat underlying conditions

Underlying conditions, such as cancer, may need to be treated to improve calcium levels.

Monitoring of Hypercalcemia Complications

As a nurse, it is essential to monitor patients with hypercalcemia closely to identify and manage any potential complications. The following parameters should be observed:

A Gold top blood vial filled with blood

Serum Calcium Levels

Serum calcium levels should be monitored regularly to assess treatment response and to identify potential complications such as hypocalcemia.

An image of the thyroid and parathyroid glands

Serum PTH levels

Measuring parathyroid hormone helps determine the etiology of the high calcium levels. If PTH is elevated, this points to primary hyperparathyroidism. If it is low, is is likely not from hyperparathyroidism.

A Gold top blood vial filled with blood

Other Labs

The nurse should monitor laboratory values such as serum calcium, magnesium, and phosphate levels and liver and kidney function tests to assess for complications and monitor treatment progress.

A Gold top blood vial filled with blood

ECG monitoring

Possible hypercalcemia complications include arrhythmias, so continuous telemetry monitoring, as well as occasional 12-lead ECGs are indicated.

Specialists?

Patients with severe hypercalcemia that warrants significant calcium-reducing therapies should have a nephrology consult on board!

Hypercalcemia and Cardiac Arrhythmias

Hypercalcemia can cause a variety of ECG changes, including:

  • ST-Segment: Elevation can occur, especially in the inferior leads (II, III, aVF), and can be shortened as well.
  • QT interval: Shortened, which can increase the risk of arrhythmias like VTACH
  • T-waves: Biphasic or widened
  • Other: J waves (osborn waves), which are typically associated with hypothermia, but severe hypercalcemia can mimic this. 

Arrhythmias are less common with hypercalcemia than with other electrolyte abnormalities but still can cause them including:

  • Atrial fibrillation (AFib): Hypercalcemia can cause AFib, a rapid and irregular heart rhythm caused by abnormal electrical activity in the atria.
  • Ventricular fibrillation (VFib): In rare cases, hypercalcemia can cause VFib, a potentially life-threatening arrhythmia that occurs when the ventricles quiver instead of contracting.
  • Ventricular Tachycardia
  • AV Blocks

These ECG changes are thought to be due to altered myocardial repolarization caused by hypercalcemia. 

Hypercalcemia is associated with ST-segment elevation and shortening, QT-interval shortening, Biphasic or widened T waves, and J waves (osborn waves)

Want to learn more?

If you want to learn more, I have a complete video course “ECG Rhythm Master”, made specifically for nurses which goes into so much more depth and detail.

With this course you will be able to:

  • Identify all cardiac rhythms inside and out
  • Understand the pathophysiology of why and how arrhythmias occur
  • Learn how to manage arrhythmias like an expert nurse
  • Become proficient with emergency procedures like transcutaneous pacing, defibrillation, synchronized shock, and more!

I also include some great free bonuses with the course, including:

  • ECG Rhythm Guide eBook (190 pages!)
  • Code Cart Med Guide (code cart medication guide)
  • Code STEMI (recognizing STEMI on an EKG)

Check out more about the course here!

In conclusion, hypercalcemia is a potentially serious condition that requires prompt diagnosis and treatment to prevent complications.

As a nurse, it is important to be aware of the causes, symptoms, and ECG changes associated with hypercalcemia, as well as the monitoring and treatment options available. By taking a proactive approach to monitoring and managing patients with hypercalcemia, nurses can help improve outcomes and prevent serious complications. 

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Download this Article!

If you’d like to download this article in PDF form, click here!

Hypocalcemia Guide for Nurses: Nursing Assessment and Management

Hypocalcemia Guide for Nurses: Nursing Assessment and Management

Published: April 10, 2023

Last Updated: April 10, 2023

William Kelly, MSN, FNP-C

Author | Nurse Practitioner

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An image of IV magnesium sulfate with Magnesium in a ball with low levels with surrounding foods that are high in magnesium

Hypocalcemia is when there are low levels of calcium in the blood. Calcium is an electrolyte that plays a vital role in many bodily functions, including muscle contraction, nerve transmission, and bone formation.

Various factors, including nutritional deficiencies, medications, and underlying medical conditions, can all lead to low calcium levels. As a nurse, it is essential to be familiar with the signs, symptoms, and treatment options for hypocalcemia to provide adequate and timely care to patients.

This article will discuss the importance of calcium in the body, the causes of hypocalcemia, nursing assessment and interventions, treatment options, and monitoring parameters for hypocalcemia.

Learn about the causes, nursing assessment, and treatment for hyperkalemia in this comprehensive guide for nurses and medical professionals.

Why is Calcium Important in the Body?

Calcium is an essential electrolyte that plays a critical role in maintaining the structure and function of our bones and teeth. It is also necessary for proper nerve function, muscle contraction (including the heart), blood clotting, and enzyme activity. In addition, calcium regulates the release of hormones and other chemicals in the body.

A normal human cell

Bones and Teeth

Calcium provides the structural support for strong and healthy bones and teeth.

A depiction of a neuron

Nerve Transmission

Calcium helps regulate the transmission of nerve impulses, which is critical for communication between the brain and other body parts.

An image of a muscle

Muscle Contraction

Calcium helps with muscle contraction and relaxation, including the muscles involved in breathing and the heart beating.

a desaturated heart and yellow cardiac conductive tissue showing the SA node, AV node, and ventricles

Cardiac Conduction

Calcium ions are necessary for the contraction of the heart muscles, but they also play a critical role in the generation and transmission of electrical impulses that coordinate the heart’s rhythm. These electrical impulses regulate the heart rate and ensure that the heart muscles contract in a coordinated manner. Without sufficient calcium, the heart may experience arrhythmias or other electrical disturbances.

A bundle of red blood cells that are clotted together

Blood Clotting

Calcium is necessary to form blood clots, which help stop bleeding after an injury.

An enzyme and two substrates

Enyzme Activity

Calcium activates and regulates a wide range of enzymes, which are essential for the body to function as it’s supposed to!

How is Calcium Regulated in the Body?

Calcium levels in the body are tightly regulated through a complex system involving hormones and their effects on the bones, intestines, and kidneys.

The regulation of calcium involves several hormones, including:

A generic hormone depiction

Parathyroid Hormone (PTH)

The parathyroid glands releases parathyroid hormone (PTH) in response to low calcium levels in the blood. It stimulates the release of calcium from bones and increases the reabsorption of calcium by the kidneys.

A yellow sun with vitamin D in the middle

Vitamin D

Vitamin D has similar effects to PTH, including increasing calcium absorption in the intestines and decreasing kidney excretion. It can also mobilize calcium from bones, but to a lesser extent than PTH.

A generic hormone depiction

Calcitonin

The C-cells of the thyroid gland release calcitonin in response to high calcium levels in the blood. It inhibits calcium release from bones and promotes calcium excretion by the kidneys. This essentially has the opposite effect of PTH.

When calcium levels fall too low, PTH is released, which causes calcium to be released from bones and increases the reabsorption of calcium by the kidneys. In addition, PTH stimulates the production of vitamin D, which helps increase calcium absorption from the intestines. These actions work together to increase calcium levels in the blood.

When calcium levels are too high, calcitonin is released, inhibiting the release of calcium from bones and promoting the kidneys’ excretion of calcium. This helps reduce calcium levels in the blood.

Overall, regulating calcium in the body is a complex process involving multiple hormones and organs. Disrupting this process can lead to hypocalcemia or hypercalcemia, which can have serious consequences.

Normal Calcium Levels & Hypocalcemia

Normal calcium levels can range from 8.5 – 10.5 mg/dL

Calcium Levels

  • Normal Levels: 8.5 – 10.5 mg/dL
  • Hypocalcemia: <8.5 mg/dL
  • Critical Hypocalcemia: <4.4 mg/dL

What are Ionized Calcium levels?

When a patient has low calcium, you may have heard that an ionized calcium level is specifically checked. 

Ionized calcium is ordered because it represents the blood’s physiologically active form of calcium.

Total calcium (checked on a BMP or CMP), includes both ionized and protein-bound calcium. Total calcium levels can be influenced by pH and albumin levels.

Ionized calcium is considered a more accurate reflection of the body’s calcium status. 

Ionized Calcium Levels

  • Normal Levels: 4.4 – 5.4 mg/dL
  • Hypocalcemia: <4.4 mg/dL
  • Critical Hypocalcemia: <3.0 mg/dL

Albumin and Calcium

Albumin is a protein in the blood that binds to calcium and other ions, reducing the amount of ionized calcium available for cellular processes.

As a result, total calcium levels may be affected by changes in albumin levels.

Ionized calcium levels are unaffected by changes in albumin levels and are considered a more accurate reflection of the body’s calcium status. This means if the calcium is low but the albumin level is also low, ionized calcium should definitely be checked. There is a correction calculator, but this isn’t always accurate so it’s best to check an ionized calcium level to verify. 

Causes Of Hypocalcemia:

There are multiple causes of hypocalcemia, including:

An image of the thyroid and parathyroid glands

Hypoparathyroidism

Hypoparathyroidism is when the parathyroid glands produce insufficient amounts of PTH, leading to decreased calcium levels in the blood. This is usually caused by surgery or radiation.

Vitamin D in a softgel

Vitamin D Deficiency

As stated above, vitamin D is essential for calcium absorption from the intestines. This means a lack of vitamin D can lead to hypocalcemia.

The kidneys, with the left one transected so you can see the inside

Chronic Kidney Disease

The kidneys play a critical role in regulating calcium levels in the blood. Chronic kidney disease can cause decreased vitamin D production, as well as too much calcium excretion.

Milk overflowing

Hyperphosphatemia

High phosphate levels lead to depositing calcium outside the blood, such as in skeletal muscle or bones.

Milk overflowing

Abnormal Magnesium Levels

Hypomagnesemia can cause parathyroid hormone resistance or decrease PTH secretion in severe cases.

Severe hypermagnesemia can also induce hypocalcemia.

An image of an inflamed appendix

Acute Pancreatitis

Acute pancreatitis can lead to calcium deposition in the pancreatic tissue, leading to decreased calcium levels in the blood.

A bottle of medications that are prescription

Medications

Certain medications can cause low calcium levels, including:

  • Bisphosphonates
  • Colchicine
  • Chemos (cisplatin)
  • Immunomodulators
  • Anticonvulsants (Dilantin, Phenobarbital)
A bag of Type A blood

Other Conditions

There are various other causes of low calcium levels, including:

  • Certain genetic conditions
  • Sepsis or severe illness
  • Post-surgical state
  • Massive blood transfusions (from citrate in the blood)

Hyperventilation

Anxiety and hyperventilation can lead to a decrease CO2 in the blood, which can result in respiratory alkalosis.

Alkalosis can cause calcium ions to bind more readily to proteins like albumin, resulting in decreased levels of ionized calcium in the blood. This is often why patient’s having panic attacks experience numbness, tingling, and even muscle spasms.

Having the patient breathe into a non-rebreather not hooked up to oxygen (or a good ole paper bag) can help them retain more CO2 and decrease symptoms. 

Nursing Assessment Of Hypocalcemia

Symptoms

Hypocalcemia can cause many symptoms, with tetany being the most common and hallmark sign.

Tetany is when there is hyper-irritability of the peripheral neurons and their control over muscles. This can range from mild symptoms to more severe symptoms. This is unlikely to occur until calcium levels below 7-7.5 mg/dL.

Symptoms of tetany include:

Lips with blue tingling numbness around it

Peri-oral numbness

Numbness and/or tingling around the mouth and lips.

A muscle with red electric bolts indicating pain

Muscle Cramps and spasms

Hypocalcemia can cause muscle cramps, carpopedal spasms, and even laryngospasms which can cause hypoxia and respiratory distress.

A hand with blue electric bolts indicating tingling

Paresthesias

The patient may have numbness or tingling of their hands or their feet.

Other generalized symptoms of hypocalcemia include:

A fatigued muscle with a sad tired expression

Muscle Weakness

Low calcium can cause generalized weakness and fatigue.

A silhouette of a head with red and orange markings above the head, indicating anxiety

Mental Health

Hypocalcemia can lead to anxiety, irritability, and even depression.

A blue brain with yellow lightning bolts depicting a seizure

Seizures

Severe hypocalcemia can cause focal or generalized seizures.

PHYSICAL Assessment

When performing a physical exam for a patient suspected of having hypocalcemia, the nurse should assess for the following:

Vital Signs

  • HR: May be irregular (indicating an arrhythmia)
  • BP: May be decreased
A face with the facial nerve present, which is causing Chvostek sign

Chvostek's Sign

Chvostek’s sign is positive when tapping the facial nerve in front of the ear causing twitching of the facial muscles on that side in patients with hypocalcemia.

  • Sensitivity: 10-64%
  • Specificity: 69-92%

This means that it is not always present in hypocalcemia, but if it is present, then hypocalcemia is a good possibility. 

 

An image of carpopedal spasms occurring with a blood pressure cuff inflated on the upper arm

Trousseau's sign

Trousseau’s sign is positive when spasms of the hand and wrist occur after inflating a blood pressure cuff above the patient’s systolic BP for 3-5 minutes.

  • Sensitivity: 30-94%
  • Specificity: 29-63%

This means it is likely more commonly present in hypocalcemia than Chvostek’s sign, but its presence doesn’t necessarily mean it is from hypocalcemia. 

There are no other specific physical findings for low calcium, but you should observe for weakness, irregular heart rhythms, and possibly painful muscles to palpation.

Also check out: “The Cranial Nerve Assessment for Nurses”

Treatment for Hypocalcemia

The treatment of hypocalcemia depends on the severity of the condition and the underlying cause. When you get a low calcium level back on the blood work of your patient, as the nurse you should:

Assess the Patient

Ensure they don’t have any symptoms and are stable, including recent vital signs.

Cardiac Monitor

Make sure your patient is on the cardiac monitor. Obtain an ECG if it still needs to be done. Close cardiac monitoring is essential when infusing electrolytes through the IV as well.

Notify the Provider

Notify the provider of the calcium levels, your assessment, and their cardiac rhythm (and if any QT prolongation is present).

Ensure IV access

Make sure there is at least one IV site, but place a second line if the hypocalcemia is severe.

Administer Treatment

Administer medications that are ordered (discussed below).

Treatment for hypocalcemia:

Treatment for hypocalcemia will depend on the severity, as well as any symptoms the patient is having. Severe symptoms that require immediate and likely IV repletion include tetany, arrhythmias, or seizures.

Bag of IV magnesium sulfate

IV Calcium

IV calcium is given for patients with severe symptomatic hypocalcemia. This includes patients with:

  • Carpopedal spasms
  • Laryngospasms
  • Bronchospasms
  • Seizures
  • Prolonged QT interval on ECG
  • Levels < 7.5 mg/dL who are at higher risk for serious complications

Calcium Gluconate 1-2g (90 – 180mg elemental calcium) in 50mL of 5% dextrose or NS infused over 10-20 minutes. This can be repeated after 10-60 minutes if needed. This is expected to raise serum calcium levels for only 2-3 hours.

After the bolus is given, a solution of 10% calcium gluconate can be used for a continuous infusion, started at 50ml/hr (11g calcium gluconate diluted in 1000ml of NS or D5W).

Calcium

Oral Calcium Supplementation

Oral calcium supplementation is started with mild symptoms or levels above 7.5 – 8.0 mg/dL, or for chronic hypocalcemia.

Patients should be given 1-2g of elemental calcium in divided doses.

Example Dosing:

  • Calcium carbonate 1250mg, Take 1 tablet PO TID
  • Calcium citrate 950mg, Take 2 tablets PO BID

 

Vitamin D softgels

Vitamin D Supplementation

Vitamin D should be started if the patient has low vitamin D levels. This is because low vitamin D levels can decrease calcium absorption in the intestines (as discussed above).

  • Ergocalciferol (D2) 50,000 iU PO weekly x 6-8 weeks
  • Cholecalciferol (D3) 50,000 iU PO weekly x 6-8 weeks

Calcitriol is a vitamin D metabolite that is preferred in patients with severe hypocalcemia, or in those with chronic kidney or liver disease. This effectively skips the need for the kidney and/or liver to process the vitamin D, leading to more rapid correction.

  • Calcitriol 0.25mcg PO BID

 

Bag of IV magnesium sulfate

Magnesium Replacement

Hypomagnesemia is a common cause of hypocalcemia, as this can cause a decrease in PTH and its efficacy.

You can read all about magnesium replacement here.

Monitoring of Hypocalcemia

As a nurse, it is essential to monitor patients with hypocalcemia closely to identify and manage any potential complications. The following parameters should be observed:

A Gold top blood vial filled with blood

Calcium Levels

Serum calcium levels should be monitored regularly to assess treatment response and to identify potential complications such as hypercalcemia. This may include ionized calcium for a more accurate reflection of calcium status. Initially may need to be checked every 4-6 hours.

A Gold top blood vial filled with blood

Other Electrolytes

Other electrolytes and monitoring of renal function should also be checked, usually daily, every morning. Important related electrolytes include:

 

A Gold top blood vial filled with blood

Other Labs

Other important tests that may be ordered with a patient with hypocalcemia includes:

  • PTH levels
  • Vitamin D levels

 

A Gold top blood vial filled with blood

Cardiac Monitoring

Patients with low calcium are at higher risk for QT prolongation and cardiac arrhythmias. They should be on a continuous cardiac monitor and have an ECG checked.

A round calcium ion Ca++

Foods High in Calcium

  1. Cheese
  2. Yogurt
  3. Milk
  4. Sardines
  5. Tofu
  6. Fortified soy, almond, and/or oat milk
  7. Fortified orange juice
  8. broccoli
  9. Kale
  10. Almonds

Hypocalcemia and Cardiac Arrhythmias

Hypocalcemia is important in the conduction and beating of the heart. Very low levels can cause ECG abnormalities and arrhythmias. Some of these arrhythmias include:

  • Torsades de Pointes: Torsades de Pointes is a type of ventricular tachycardia characterized by twisting the QRS complex around the isoelectric line.
  • Atrial fibrillation: Hypocalcemia can increase the risk of atrial fibrillation, due to impaired atrial and AV nodal conduction.
  • Ventricular Tachycardia: Hypocalcemia-induced VTACH can occur due to increased automaticity of the ventricular myocardium.
  • Premature ventricular contractions (PVCs): Hypocalcemia can increase the risk of PVCs, which are abnormal contractions that originate from the ventricles rather than the atria.
  • Atrioventricular (AV) blocks: Hypocalcemia can cause AV blocks, which occur when there is impaired conduction between the atria and ventricles.

On ECG, hypocalcemia can manifest in the following ways:

  • QT interval: Hypocalcemia can prolong the QT interval on ECG, increasing the risk of arrhythmias such as torsades de pointes.
  • ST-Segment: Hypocalcemia can also prolong the ST-segment. This is because low calcium levels can delay the repolarization of the heart muscle, leading to a prolonged ST segment.
QT interval prolongation and ST-segment prolongation with hypocalcemia
Torsades De Pointes is a polymorphic VTACH that occurs due to QT prolongation

Hypocalcemia can also cause Torsades de Pointes, a type of polymorphic ventricular tachycardia that is deadly and quickly degenerates into Ventricular fibrillation if not treated ASAP. This does not happen as commonly as with hypomagnesemia. 

Want to learn more?

If you want to learn more, I have a complete video course “ECG Rhythm Master”, made specifically for nurses which goes into so much more depth and detail.

With this course you will be able to:

  • Identify all cardiac rhythms inside and out
  • Understand the pathophysiology of why and how arrhythmias occur
  • Learn how to manage arrhythmias like an expert nurse
  • Become proficient with emergency procedures like transcutaneous pacing, defibrillation, synchronized shock, and more!

I also include some great free bonuses with the course, including:

  • ECG Rhythm Guide eBook (190 pages!)
  • Code Cart Med Guide (code cart medication guide)
  • Code STEMI (recognizing STEMI on an EKG)

Check out more about the course here!

Hypocalcemia is an important electrolyte abnormality that must be recognized and treated quickly in the inpatient and ER settings. This is often caused by hypoparathyroidism, vitamin D deficiency, chronic kidney disease, or certain medications. It can cause symptoms such as tetany, evidenced sometimes by positive Chvostek or Trusseau signs. 

Treatment involves oral or IV calcium and supplementation of Vitamin D and/or magnesium if applicable. Monitoring involves checking electrolytes, labs like PTH and Vitamin D, and montioring the ECG and continuous cardiac monitor. 

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Download this Article!

If you’d like to download this article in PDF form, click here!

References

UpToDate & Other Database Sources:

Textbooks

Other:

  • The diagnostic accuracy of clinical diagnostic tests in assessing patients with potential calcium disorders: A systematic review and meta-analysis. (European Journal of Internal Medicine)

    Managing hypomagnesemia: A complete guide to nursing assessment and treatment of low magnesium levels

    Managing hypomagnesemia: A complete guide to nursing assessment and treatment of low magnesium levels

    Published: March 26, 2023

    Last Updated: April 10, 2023

    William Kelly, MSN, FNP-C

    Author | Nurse Practitioner

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    An image of IV magnesium sulfate with Magnesium in a ball with low levels with surrounding foods that are high in magnesium

    Hypomagnesemia, the medical term for low magnesium levels in the blood, can have disastrous consequences if left untreated. Magnesium is crucial in numerous bodily functions, including nerve and muscle function, heart rhythm, and bone health. Hypomagnesemia can lead to serious complications, such as seizures, cardiac arrhythmias, and even death. 

    As a nurse, knowing the causes, symptoms, and treatment of hypomagnesemia is essential to provide effective care and improving patient outcomes. This article will provide a comprehensive guide to nursing assessment and treatment of hypomagnesemia, including its causes, clinical manifestations, nursing assessment, treatment, and monitoring.

    Learn about the causes, nursing assessment, and treatment for hyperkalemia in this comprehensive guide for nurses and medical professionals.

    Why is Magnesium So Important in the Body?

    Magnesium is an electrolyte that is so important for our body’s daily functioning. Magnesium is essential from the cardiovascular system to our muscular system and energy metabolism! When low magnesium levels occur, this can cause issues in these areas! Magnesium functions in the following ways:

    An illustration of the heart with the pulmonary and aortic vessels

    Cardiac Function

    Magnesium acts similarly to a calcium channel blocker, helping to regulate the influx of calcium to control the proper timing and duration of electrical impulses in the heart. It also plays a crucial role in stabilizing the cell membrane and maintaining the resting membrane potential. Hypomagnesemia and low magnesium levels can lead to deadly cardiac arrhythmias.

    An image of a muscle

    Muscle Function

    Magnesium is important in the contraction of muscles as well as their relaxation. This helps with the funcitoning of cardiac muscle tissue, the GI system, and skeletal muscle tissue. It also relaxes the smooth muscle in the vessel walls, reducing blood pressure and preventing spasms.

    An image depicting ATP

    Energy Metabolism

    Magnesium is necessary for metabolism as it is a co-factor for many enzymes involved in producing ATP – the body’s primary energy source on a cellular level. It’s also involved in the regulation of glucose metabolism and insulin signaling.

    A depiction of a neuron

    Nerve Transmission

    Magnesium is involved in transmitting nerve impulses and coordinating muscle movements, as it helps regulate the release of neurotransmitters and the activation of ion channels.

    A normal human cell

    Bone Health

    Magnesium supports the structural integrity of bones and teeth. It is also a co-factor for enzymes that regulate bone metabolism, and low magnesium levels are associated with osteoporosis.

    How is Magnesium Regulated in the Body?

    Magnesium, like potassium, is tightly regulated to maintain proper body function and prevent hypomagnesemia and low magnesium levels from occurring. The regulation of magnesium involves a complex interplay of factors, including dietary intake, absorption, excretion, and hormonal mechanisms.

    A depiction of the small bowel, which is largely responsible for absorption of magnesium

    Intake & Absorption

    The body regulates its magnesium levels by adjusting how much magnesium it absorbs in the small intestine. When there are low magnesium levels, the absorption increases to prevent hypomagnesemia. The opposite is true as well!

    A muscle with red electric bolts indicating pain

    The Kidneys

    The kidneys play a crucial role in regulating the excretion of magnesium, similar to its role in potassium.

    A depiction of the parathyroid gland

    Hormones

    Several hormones can influence magnesium levels. These include the Parathyroid hormone (PTH), which increases GI absorption and decreases kidney excretion. Vitamin D also stimulates magnesium absorption in the small intestines and regulates the activity of PTH.

    A liquid drop with "H+" indicating acid or acidity or hydrogen ions

    Acid-base Balance

    Similar to hypokalemia, acid-base balance can also influence magnesium levels. Acidosis can cause magnesium to shift out of cells into the bloodstream and extracellular space. Alkalosis causes the opposite, leading to hypomagnesemia.

    Normal Magnesium Levels & Hypomagnesemia

    Normal magnesium levels can range from 1.7 to 2.2 mg/dL. However, only about 1% of the body’s magnesium levels are in the blood. 50-60% of magnesium is stored in the bone, and the rest is located in the muscles, soft tissues, and red blood cells.

    Magnesium Levels

    • Normal Levels: 1.9 – 2.2 mg/dL

    • Mild Hypomagnesemia: 1.6 – 1.9 mg/dL

    • Moderate Hypomagnesemia: 1 – 1.5 mg/dL

    • Severe Hypomagnesemia: <1 mg/dL

    Causes Of Hypomagnesemia:

    Several factors can contribute to hypomagnesemia, including inadequate dietary intake, malabsorption, renal losses, medications, and certain medical conditions. Understanding the underlying causes of low magnesium levels is essential for appropriate treatment and preventing long-term complications for our patients.

    The colon with liquid diarrhea dripping out

    GI Losses

    Hypomagnesemia can occur with excessive vomiting or diarrhea but occurs more often with diarrhea (it has 15x more magnesium in stool than in vomit).

    Certain GI conditions that affect magnesium absorption include irritable bowel disease (IBD – AKA Crohn’s or ulcerative colitis), celiac disease, and pancreatitis.

     

    A purple and gray pill, depicting omeprazole, which can lead to hypomagnesemia and low magnesium levels

    Medications

    Medications that increase magnesium loss from the GI system include chronic proton pump inhibitors (PPIs) like Omeprazole may lead to low magnesium levels. Other medications which can do this include H2 blockers, Antacids, and even laxatives.

    The kidneys, with the left one transected so you can see the inside

    Renal Losses

    Conditions that can lead to excessive kidney magnesium loss include renal tubular acidosis, hyperaldosteronism, and even diabetes. Certain medications can also impact this (discussed below).

    A bottle of medications that are prescription

    Medications

    Medications that can increase the excretion of magnesium in the kidneys include loop diuretics and thiazide diuretics. Other drugs that can cause hypomagnesemia include Aminoglycoside antibiotics, certain chemotherapies, calcineurin inhibitors, and Digoxin.

    Alcohol whiskey bottle and glass with ice

    Alcohol

    Chronic alcoholism can impair magnesium absorption in the small intestine and increase excretion in the urine, leading to hypomagnesemia. This magnesium wasting in the urine is reversible after four weeks of sobriety.

    A donation box of ice with a kidney in it

    Post-transplant

    Patient’s with an organ transplant are more likely to experience hypomagnesemia, likely from their calcineurin inhibitor medications (like tacrolimus).

    Milk overflowing

    Hypercalcemia

    High calcium levels can lead to mildly low magnesium levels.

    A strand of DNA

    Genetic Causes

    Certain rare genetic conditions can cause decreased magnesium absorption in the small intestine and increased renal magnesium wasting.

    Nursing Assessment Of Hypomagnesemia

    Symptoms

    Symptoms of hypomagnesemia (low magnesium levels) will depend on the patient and the severity of their hypomagnesemia. As the magnesium levels drop, the symptoms become more pronounced, severe, and potentially life-threatening.

    A fatigued muscle with a sad tired expression

    Muscle Weakness

    Like low potassium, muscle weakness is common with hypomagnesemia. They may experience fatigue and muscle weakness in their legs which can cause difficulty walking, as well as weakness of any other muscles in their body.

    A muscle with red electric bolts indicating pain

    Muscle Cramps & Twitching

    Patients may feel tingling sensations and experience involuntary muscle contractions, particularly in their hands or lower extremities.

    A cardiac monitor showing ventricular tachycardia

    Cardiac Arrhythmias

    As discussed above, magnesium is essential in the conduction as well as the mechanical beating of the heart. If an arrhythmia occurs, patients may experience palpitations, chest pain, shortness of breath, dizziness, or even syncope. Cardiac arrest is possible if they go into a deadly rhythm like VFIB.

    The colon with liquid diarrhea dripping out

    GI Symptoms

    Low magnesium levels can cause nausea, vomiting, or abdominal cramping. Additionally, if the patient has diarrhea, that may be a clue on the cause.

    A brain with yellow connecting lights which indicate the central nervous sytem

    Neuro Symptoms

    Magnesium can cause CNS hyperirritability, leading to confusion, irritability, hyperactive deep tendon reflexes, paresthesias, and seizures.

    PHYSICAL Assessment

    The physical assessment of a patient with hypomagnesemia will also depend on the severity of the low magnesium levels and other factors. 

    Vital Signs

    • HR: May be fast or slow, depending on any arrhythmias.
    • BP: May be increased
    • Respirations: usually normal
    • SPO2: Usually normal
    • Temp: Normal

    Inspection

    • Muscle weakness or trouble walking or moving
    • May appear fatigued or lethargic

    Auscultation

    • Auscultate for an Irregular heartbeat
    a gloved hand palpating unspecified skin

    Palpation

    • May have tender muscles
    • Edema or ascites may indicate underlying kidney or liver failure
    • Abdominal tenderness may be present, especially with any GI symptoms

    Overall, while the nursing assessment of hypomagnesemia may not reveal many specific physical findings, monitoring for muscle weakness, irregular heart rhythms, and signs of potential underlying issues such as edema, ascites, and abdominal tenderness is important for identifying the condition and providing appropriate interventions to manage hypomagnesemia and prevent complications.

    Treatment for Hypomagnesemia

    The treatment for hypomagnesemia depends on the underlying cause, severity, and serum magnesium levels.

    When you get your patient’s results back, and they show hypomagnesemia, then follow the following general interventions:

    Assess the Patient

    Ensure they don’t have any symptoms and are stable, including recent vital signs.

    Cardiac Monitor

    Make sure your patient is on the cardiac monitor. Obtain an ECG if it still needs to be done. Close cardiac monitoring is essential when infusing electrolytes through the IV as well.

    Notify the Provider

    Notify the provider of the potassium levels, your assessment, and their cardiac rhythm. They will order the treatment for hypomagnesemia!

    Ensure IV access

    Make sure there is at least one IV site, but place a second line if the hypomagnesemia is severe.

    Evaluate Medications

    Evaluate if they are on any medications which may lead to hypomagnesemia listed above.

    Administer Treatment

    Administer medications that are ordered (discussed below).

    Treatment for Hypomagnesemia (medications):

    Treatment for hypomagnesemia will depend on the severity, as well as any symptoms the patient is having. Severe symptoms that require immediate and likely IV repletion include tetany, arrhythmias, or seizures.

    The kidneys, with the left one transected so you can see the inside

    Address Underlying Causes

    Figuring out why the magnesium is low is essential, but there shouldn’t be any reason to delay replacing the magnesium with Oral or IV options. However, addressing the underlying cause can prevent further loss of magnesium and prevent it from happening again.

    pills of magox

    Oral Magnesium Supplementation

    PO magnesium is the standard for mild to moderate hypomagnesemia, primarily if there are no or minimal symptoms.

    There are many different variations of magnesium pills, such as:

    • Magnesium Oxide: Most common and inexpensive, but it has a low absorption rate and may cause diarrhea.
    • Magnesium Chloride: Has better absorption and higher bioavailability than magnesium oxide. Also less likely to cause GI side effects and may be better for skin health and wound healing.
    • Magnesium Carbonate: Good for heartburn, but not the best absorption.
    • Magnesium L-lactate: Less likely to cause GI symptoms like diarrhea.
    • Magnesium Glycinate: Highly absorbable and less likely to cause diarrhea. It may have a calming effect on the body.
    • Magnesium Citrate: Good absorption rate but also a laxative and will cause diarrhea and cramping. They are not typically used for magnesium replacement.

    Generally, sustained release options are better because they minimize the renal wasting of the magnesium. Common options include:

    • Magnesium Chloride 64-71.5mg elemental magnesium, 6-8 tabs in divided doses
    • Magnesium L-lactate with 84mg elemental magnesium, 6-8 tabs in divided doses

    If the sustained release is unavailable, magnesium oxide 800-1600mg daily in divided doses may be used, but diarrhea may occur.

    Bag of IV magnesium sulfate

    IV Magnesium Sulfate

    IV magnesium is given to patients with severe symptoms or who are NPO for whatever reason.

    IV replacement dosing will depend on the severity:

     

    • Mild (1.6 – 1.9 mEq/L): 1-2 grams of mag sulfate over 1 – 2 hours
    • Moderate (1.0 – 1.5 mEq/L): 2 – 4 grams of mag sulfate over 4 – 12 hours
    • Severe (< 1.0 mEq/L): 4 – 8 grams of mag sulfate over 12 – 24 hours

    Kidney Failure

    Patients in renal failure should be cautiously replaced with electrolytes like magnesium and potassium, as their ability to excrete those electrolytes is impaired. Therefore, dosing should generally be cut in half, and levels should be closely monitored.

    Patients should generally be maintained on magnesium replacement for 1-2 days after the levels have normalized to replete intracellular magnesium. However, if ongoing losses occur, chronic therapy may be needed.

    Monitoring of Hypomagnesemia

    Monitoring patients with hypomagnesemia involves cardiac monitoring and trending the magnesium levels.

    A Gold top blood vial filled with blood

    Magnesium Levels

    Magnesium levels are generally checked at least daily while inpatient until normalization of the magnesium level.

    A Gold top blood vial filled with blood

    Other Electrolytes

    Other electrolytes and monitoring of renal function should also be checked, usually daily, every morning.

    A Gold top blood vial filled with blood

    Cardiac Monitoring

    Patients with low magnesium are at high risk for cardiac arrhythmias. Additionally, anybody receiving IV replacement with magnesium should be on a cardiac monitor.

    Foods High in Magnesium

    1. Seeds & Nuts (Pumpkin seeds, chia seeds, almonds, Cashews, peanuts)
    2. Spinach
    3. Dark Chocoloate
    4. Black Beans
    5. Avocados
    6. Salmon
    7. Quinoa
    8. Soymilk

    Hypomagnesemia and Cardiac Arrhythmias

    Magnesium is an important electrolyte that plays a crucial role in cardiac function, particularly in maintaining normal cardiac rhythm. Hypomagnesemia and low magnesium levels can lead to various cardiac arrhythmias, including:

    • Torsades de Pointes: Torsades de Pointes is a type of ventricular tachycardia characterized by twisting the QRS complex around the isoelectric line. It can occur in patients with hypomagnesemia and prolongation of the QT interval and is classic with hypomagnesemia.
    • Atrial fibrillation: Hypomagnesemia can increase the risk of atrial fibrillation due to magnesium’s effect on atrial muscle cells.
    • PVCs: Low magnesium leads to impaired ion channels, leading to excitable cardiac conduction, which can trigger PVCs or VTACH.

    On ECG, hypomagnesemia can manifest in the following ways:

    • Prolonged QT interval: Hypomagnesemia can prolong the QT interval, leading to an increased risk of Torsades de Pointes.
    • Widened QRS complex: Hypomagnesemia can cause a widened QRS complex, which can be seen on ECG.
    • ST segment and T wave changes: Hypomagnesemia can cause ST segment depression and flattening or inversion of T waves on ECG.

    It is important to note that hypomagnesemia can also exacerbate cardiac arrhythmias caused by other electrolyte imbalances, such as hypokalemia and hypocalcemia.

    Nurses should be aware of the potential cardiac complications associated with hypomagnesemia and monitor patients for signs and symptoms of arrhythmias. Timely recognition and treatment of hypomagnesemia can help prevent severe cardiac complications.

    A graph of a PQRST complex with changes associated with Hypomagnesemia, including QRS widening, QT prolongation, and flattened or inverted T waves
    Torsades De Pointes is a polymorphic VTACH that occurs due to QT prolongation

    Hypomagnesemia is associated with Torsades de Pointes, which is a type of polymorphic ventricular tachycardia that is deadly and will quickly degenerate into Ventricular fibrillation if not treated ASAP. Treatment involves following ACLS protocol, but often IV magnesium is given rapidly if hypomagnesemia is suspected as a cause.

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    If you want to learn more, I have a complete video course “ECG Rhythm Master”, made specifically for nurses which goes into so much more depth and detail.

    With this course you will be able to:

    • Identify all cardiac rhythms inside and out
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    Hypomagnesemia is a condition that nurses should be familiar with, as it can have significant implications for patient health. Magnesium is vital in various bodily functions, including the cardiac, nervous, and gastrointestinal systems.

    The body regulates it through dietary intake, absorption, excretion, and hormonal factors. Various factors, such as chronic diarrhea, alcoholism, and certain medications, can cause hypomagnesemia. Treatment often involves magnesium replacement, either orally or intravenously, and addressing any underlying conditions that may contribute to the deficiency.

    Nurses are essential in identifying and monitoring hypomagnesemia and low magnesium levels and educating patients on the importance of adequate magnesium intake and potential risk factors. Nurses can provide optimal care and improve patient outcomes by understanding hypomagnesemia’s causes, symptoms, and treatment.

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    Treatment for Hyperkalemia: A nurse’s comprehensive guide to high potassium levels

    Treatment for Hyperkalemia: A nurse’s comprehensive guide to high potassium levels

    Published: March 19, 2023

    Last Updated: March 23, 2023

    William Kelly, MSN, FNP-C

    Author | Nurse Practitioner

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    Treatment for hyperkalemia including IV Calcium gluconate, IV insulin, and IV dextrose 50%

    Treatment for Hyperkalemia is essential in the hospital and acute care settings, as it can be deadly!

    Hyperkalemia is when a patient’s serum potassium level rises above 5.0 mEq/L. This potentially life-threatening medical condition is one that nurses must be familiar with, as this can lead to cardiac arrhythmias and cardiac arrest. 

    Nurses are crucial in preventing, detecting, and managing hyperkalemia through various nursing interventions and treatment options. This article will discuss the causes of hyperkalemia, nursing interventions, and treatment of hyperkalemia, providing nurses with the knowledge and tools necessary to identify and manage this deadly condition.

    If you haven’t read the article on Hypokalemia, be sure to read that post first as it has some great background information about how the body regulates potassium in the body!

    Learn about the causes, nursing assessment, and treatment for hyperkalemia in this comprehensive guide for nurses and medical professionals.

    Hyperkalemia And Normal Potassium Levels

    Potassium Levels

    The normal range for potassium levels within the body is 3.5-5.0 mEq/L. Hyperkalemia is any level that is higher than 5.0 mEq/L

     

    • Normal = 3.5 – 5.0 mEq/L
    • Mild Hyperkalemia: 5.1 – 5.9 mEq/L
    • Moderate Hyperkalemia: 6.0 – 6.9 mEq/L
    • Severe Hyperkalemia: > 7.0 mEq/L

    The higher the level, the more likely your patient will experience side effects or complications from hyperkalemia.

    Remember that this is the level of potassium that is OUTSIDE the cells of the body. The actual amount (3.5-5mEq/L) is very low. However, the inside of the cell usually has 120-150mEq/L… That’s 30 times the level from the outside! This is why conditions that cause lysis of cells on a large scale can cause large increases in hyperkalemia.

    Causes Of Hyperkalemia:

    We discussed in the previous article about how potassium regulates the body and understanding how potassium works and then also what causes high potassium levels is important to understand before diving into the treatment for hyperkalemia.

    There are various causes of hyperkalemia, including:

    Renal Failure

    The kidneys are the main way the body regulates potassium levels. When potassium levels are too high, the kidneys will excrete excess potassium. When the kidneys don’t work like they should and can’t filter out the excess potassium like usual, this is really the primary reason you’ll see potassium levels rise significantly in the blood. This can be from acute or chronic kidney disease.

    A bottle of medications that are prescription

    Medications

    Certain medications can cause an increase in serum potassium levels, such as lisinopril, potassium-sparing diuretics (like Spironolactone), and even NSAIDs. These impact how the kidneys normally excrete potassium. Beta-blockers even can increase potassium levels, but to a lesser degree (usually < 0.5 mEq/L elevation).

    A liquid drop with "H+" indicating acid or acidity or hydrogen ions

    Metabolic Acidosis

    Acidosis, when a buildup of hydrogen ions in the blood, causes a potassium shift from inside to outside the cells, leading to hyperkalemia.

    What about Respiratory acidosis?

    Respiratory acidosis is largely caused by an excess buildup of CO2 in the blood. Since CO2 is a small, uncharged molecule, it can easily diffuse across the cell membrane and does not directly affect potassium levels within cells. Therefore, in respiratory acidosis, potassium levels in the blood are generally not significantly affected.

    An organic chemistry representation of aldosterone the hormone

    Hormones

    Insulin and aldosterone both impact potassium levels.

    A deficiency in insulin (such as with DKA) leads to potassium accumulation outside the cell.

    In hypoaldosteronism (Addison’s disease), there is not enough aldosterone. Aldosterone normally promotes potassium excretion in the kidney. So not having enough leads to higher potassium levels.

    You’ll see later that we can utilize one of these hormones in the actual treatment for hyperkalemia!

    A red cell that is bursting open, releasing its contents into the extracellular space

    Hemolysis & Tissue Injury

    When a cell lyses or splits open, its contents are released into the extracellular space. As we discussed, potassium concentration is much higher in the cells.

    Whenever a condition or injury leads to massive destruction and lysis of cells, this can lead to hyperkalemia.

    These conditions include major trauma, crush injuries, tumor-lysis syndrome, rhabdomyolysis, major burns, and hemolytic anemia.

    A bottle of medications that are prescription

    Medications that Can Cause Hyperkalemia

    • ACEI/ARBs: Lisinopril, ramipril, and losartan can all cause increased potassium levels by reducing/blocking aldosterone.
    • Potassium-Sparing Diuretics: Potassium-sparing diuretics like Aldactone, Spironolactone, and amiloride block the action of aldosterone in the kidneys, leading to decreased potassium excretion.
    • NSAIDs: NSAIDs, such as Ibuprofen or Toradol, interfere with the production of prostaglandins, which regulate potassium levels in the kidneys.
    • Beta-Blockers: While this is usually a mild effect, non-selective beta-blockers (like propranolol or atenolol) decrease potassium uptake into cells, which can lead to a mild increase in potassium.
    • Digoxin: Digoxin can interfere with the sodium-potassium pump and increase blood potassium levels.

      Part of the treatment for hyperkalemia is avoiding these medications!

      A strand of DNA

      Risk Factors for Hyperkalemia

      • CKD: Chronic kidney disease can lead to the inability to regulate potassium levels efficiently
      • Diabetes: Especially with uncontrolled type 1 diabetes, the absolute lack of insulin can lead to elevated potassium levels.
      • Older age: Older patients have less efficient kidneys, as well as often have comorbid conditions.
      • Trauma or Burn patients: As stated above, trauma and burns can cause rapid release of potassium into the blood from damaged tissue.
      • Addison’s Disease: These patients are at increased risk of hyperkalemia due to a lack of aldosterone.

      What is PseudoHyperkalemia?

      Pseudohyperkalemia is essentially a “false positive” elevation of potassium. This occurs during the blood draw or after the blood has been drawn. It’s important to recognize cases of “fake” high potassium before implementing treatment for hyperkalemia, as this can lead to hypokalemia!

      Possible causes of pseudohyperkalemia include:

      Red blood cells bursting open, indicating hemolysis

      Hemolysis of the blood sample

      Blood sample hemolysis usually occurs when drawing blood draw from mechanical trauma. This often occurs if the catheter is against the vein wall and causes red blood cell lysis during the draw. This blood can have a red tint due to released hemoglobin.

      An animal cell with arrows pointing in and out of the cell membrane, indicating redistribution of potassium across the cell membrane

      Potassium Shifts

      Repeated fist-clenching can cause potassium to shift out of the muscles temporarily. This can lead to elevations by more than 1-2 mEq/L in that forearm.

      A half-eaten banana, indicating low potassium levels

      Leukocytosis or Thrombocytosis

      Significant elevations in platelet levels and very high WBCs (in the setting of chronic lymphocytic leukemia) can cause false potassium elevations, since the white blood cells are very fragile and break after the draw.

      A strand of DNA

      Genetic Condition

      Certain forms of hereditary pseudohyperkalemia exist due to potassium shifting out of red blood cells.

      Whenever a high potassium level comes back and the clinical picture doesn’t make sense (such as normal renal function, no symptoms, and no other findings), then suspect pseudo-hyperkalemia.

      Nursing Assessment Of Hyperkalemia

      Symptoms

      Symptoms of hyperkalemia will vary depending on the patient and how severe the hyperkalemia is. The higher the potassium level, the more likely the patient will exhibit symptoms, and the worse they often are, the more quickly treatment for hyperkalemia will need to be initiated!

      Some possible symptoms of hyperkalemia or high potassium include:

      A weak arm with no muscle, indicating muscle weakness

      Muscle Weakness

      Muscle weakness can also be a sign of hyperkalemia, just as it can be a sign of hypokalemia. As potassium levels rise, there can initially be increased contractions and cause spasms and twitches.

      However, as the potassium level continues to rise, skeletal muscle excitability decreases, resulting in muscle weakness and even paralysis.

      A cardiac monitor showing ventricular tachycardia

      Cardiac Arrhythmias

      Symptoms of cardiac arrhythmias may occur if the patient is experiencing an arrhythmia, such as palpitations, chest pain, Shortness of breath, dizziness, or syncope.

      The colon with liquid diarrhea dripping out

      GI Symptoms

      High potassium levels can affect the smooth muscles of the GI tract, leading to nausea, vomiting, and possibly abdominal pain/cramping or diarrhea.

      A hand with blue electric bolts indicating tingling

      Paresthesias

      Like with hypokalemia, hyperkalemia can also cause numbness or tingling, typically in the extremities or the face.

      A kidney with low fluid levels

      Shortness of breath

      This is usually only in severe cases with severe muscle fatigue of the respiratory muscles, and the patient may even need to be intubated.

      A silhouette of a head with red and orange markings above the head, indicating anxiety

      Anxiety & Irritability

      High potassium levels can also agitate the central nervous system, leading to anxiety or restlessness.

      PHYSICAL EXAM

      The physical assessment of a patient with hyperkalemia will also depend on the severity of the potassium and other factors, but most patients will have no specific physical findings.

      Vital Signs

      • HR: May be fast or slow, depending on any arrhythmias. It may also be abnormal.
      • BP: Severe hyperkalemia can cause hypotension.
      • Respirations: usually normal, but may be increased or decreased if respiratory failure is present
      • SPO2: Usually normal
      • Temp: Normal

      Inspection

      • Abdominal distention or bloating
      • Bradycardia or arrhythmias on the monitor
      • Respiratory distress in severe cases
      • Patient may appear anxious or irritable, restless, or even confused

      Auscultation

      • Listen for slow or irregular heart rhythm, which may be caused by ectopy or arrhythmia from the hyperkalemia. May also have diminished or absent S3 and S4 heart sounds.
      a gloved hand palpating unspecified skin

      Palpation

      • Muscle weakness in the lower or upper extremities, particularly in the legs. These muscles may be tender to palpation.
      • Weak or thready pulses in the extremities (radial pulse)
      • Abdominal tenderness or discomfort

      Treatment for Hyperkalemia

      The treatment for hyperkalemia depends on the underlying cause, severity, and serum potassium level.

      When you get your patient’s results back, and they show hyperkalemia, especially >5.5 mEq/L, then follow the following general interventions:

      Assess the Patient

      Ensure they don’t have any symptoms and are stable, including recent vital signs.

      Cardiac Monitor

      Make sure your patient is on the cardiac monitor. Obtain an ECG if it still needs to be done. Close cardiac monitoring is essential when infusing electrolytes through the IV as well, as some electrolytes like calcium are essential in the treatment for hyperkalemia!

      Notify the Provider

      Notify the provider of the potassium levels, your assessment, and their cardiac rhythm. The treatment for hyperkalemia will be ordered by them!

      Ensure IV access

      Make sure there is at least one IV site, but place a second line if the hyperkalemia is severe.

      Evaluate Medications

      Evaluate if they are on any medications which may lead to hyperkalemia listed above.

      Administer Treatment For Hyperkalemia

      Administer medications that are ordered (discussed below).

      Treatment for Hyperkalemia

      The treatment of hyperkalemia will depend on how severe the level is and any symptoms or cardiac arrhythmias the patient is currently experiencing. The patient’s Provider team will order this. Treatment generally includes:

      The kidneys, with the left one transected so you can see the inside

      Address Underlying Causes

      Identifying and addressing the underlying causes of hyperkalemia. The first thing would be to look at their renal function on their labs – if it is elevated, the high potassium level is likely true. Ensure it is true hyperkalemia instead of pseudohyperkalemia as above.

      A bottle of potassium supplements

      Avoid More Potassium

      Avoid potassium supplements or foods rich in potassium until the potassium has normalized. All medications which can worsen hyperkalemia should be stopped.

      A 10-ml vial of calcium gluconse 10% with 10mL drawn up into a syringe

      IV Calcium

      Calcium is a very important part of the treatment for hyperkalemia. When given, it stabilizes cardiac conduction and decreases the risk of arrhythmias such as Vfib or VTACH.

      Calcium gluconate is preferred, with the dose being 1,000mg (10mL of 10% solution) infused over 2-3 minutes. This dose can be repeated if ECG changes persist.

      As with any electrolyte, your patient should be on the cardiac monitor during this infusion.

      What about Calcium Chloride?

      Calcium chloride (from the code cart) can also be given in a similar dose (500-1000mg).  This does actually deliver 3-times the concentration of elemental calcium. However, it does irritate the vein and can cause tissue necrosis if extravasation occurs.

      IV inuslin bottle with insulin syringe drawn up to 10 units

      IV Insulin

      IV insulin is given to all patients (not just patients with diabetes) with moderate to severe hyperkalemia when dialysis is not readily available/indicated, since insulin drives potassium into the cells. This is a temporary fix but will decrease potassium levels by about 1 mEq/L pretty quickly, lasting for about 4-6 hours. The dose may need to be repeated at that time.

      Please note this should be given with dextrose so it doesn’t cause hypoglycemia. Patients who’s glucose is > 250 can receive the insulin alone.

      Glucose monitoring should be monitored every hour for 5-6 hours.

      A code cart box of dextrose 50% with the auto-injector ready to inject

      IV Dextrose

      Dextrose is given with insulin to prevent hypoglycemia but can also lead to endogenous insulin secretion, which further enhances the potassium-reducing effect.

      The dosage is typically 25gm, or 1 full amp (the total amount in the code cart). This is pushed slowly and is very thick and sticky.

      Even with one amp given, hypoglycemia still occurs in many patients. It’s recommended to start a 10% dextrose infusion at 50-75ml/hr until 5-6 hours after administering the insulin.

      A person with a nebulizer on their face

      Beta-2 Adrenergic Agonist

      Beta-agonists, such as albuterol, are sometimes used as a treatment for hyperkalemia to cause a shift of potassium into the cells (similar to the effect of insulin). This is not always ordered but should be considered in patients with significant symptoms or ECG changes despite the above treatment.

      Beta-agonists can reduce potassium levels by 0.5 – 1.5 mEq/L, and is usually given in an hour-long treatment. SubQ Terbutaline is an alternative to albuterol.

      This will also increase heart rate, and patients with heart disease and at risk for cardiac complications may be better off not getting a beta-agonist.

      A code cart box of sodium bicarb with the auto-injector ready to inject

      IV Sodium Bicarb

      Sodium bicarbonate can reduce potassium levels in patients with metabolic acidosis. 1 amp (50 mEq) can be given in 50ml, or alternatively 150mEq can be given in 1 L of 5% Dextrose over 2-4 hours.

      This treatment for hyperkalemia should be limited to patients with metabolic acidosis, and multiple doses can lead to hypernatremia.

      A bottle of kayexalate

      Remove Potassium from the Body

      Shifting the potassium into the cells is a great short-term solution to prevent complications from hyperkalemia. Still, the true treatment for hyperkalemia is removing excess potassium from the body.

      Removing potassium from the body is done in 3 main ways.

      1. Through the Urine: Giving loop diuretics, like Lasix, to patients who do not have severe kidney failure can help excrete excess potassium in the urine. This is often given in addition to IV fluids to maintain fluid balance (unless they are hypervolemic to begin with).
      2. Through the Stool: The administration of potassium-binders is standard to remove excess potassium. Traditionally this was usually Kayexalate (sodium polystyrene sulfonate), and is still often used. HOWEVER, there is newer cation exchangers that are preferred with less complications – namely Patiromer (Veltassa) or Sodium Zirocinum Cyclosilicate (SZC). Veltassa is preferred since it has a more rapid onset and is less likely to cause bowel necrosis (a rare complication from Kayexlate).If the patient is NPO for whatever reason, these can also be given as an enema.
      3. Through a Machine: Hemodialysis should be done in patients with severe kidney function impairment and is usually the best option for severe hyperkalemia, especially if the patient already has dialysis access or is newly diagnosed with severe renal failure.

      Monitoring after Treatment for Hyperkalemia:

      Patients with hyperkalemia need good monitoring, especially if they have moderate to severe hyperkalemia.

      A Gold top blood vial filled with blood

      Potassium Levels

      Potassium levels will be redrawn and assessed depending on the severity and what type of treatment for hyperkalemia was ordered.

      Mild to moderate levels can be rechecked in 4-6 hours, but severe hyperkalemia may need to be checked more frequently.

      A Gold top blood vial filled with blood

      Glucose Levels

      If insulin is given, glucose levels must be checked hourly for 4-6 hours, as hypoglycemia is common (even if you administer dextrose).

      A Gold top blood vial filled with blood

      Other Labs

      Closely monitor the patient’s renal function (BUN & Creatinine), other electrolytes, and acid-base balance (CO2).

      A Gold top blood vial filled with blood

      Cardiac Monitoring

      As discussed, high potassium levels can lead to bradycardia and arrhythmias. Continuous cardiac monitoring should be maintained, and intermittent ECGs may also be warranted.

      A Gold top blood vial filled with blood

      Respiratory Function

      Severe hyperkalemia can cause respiratory failure, so monitoring their breathing, lung sounds, respiratory rate, and pulse ox is important.

      A Gold top blood vial filled with blood

      Vital Signs

      Vital signs should be checked per facility protocol.

      A graduated cylinder with urine in it

      Urine Output

      Monitoring urine output is important, especially in patients where loop diuretics are given, and potassium is being wasted through the kidneys.

      Hyperkalemia and Cardiac Arrhythmias

      Potassium is very important in the heart’s conductive system and for each heartbeat. The higher the potassium level, the more likely ECG changes may be seen, and the higher chance that an arrhythmia may occur.

      The more common arrhythmias associated with hyperkalemia are sinus bradycardia, AV blocks, VTACH, Vfib, and asystole.

      On the ECG, hyperkalemia can manifest in a few ways, including:

      • P Waves: Decreased amplitude of P waves is common
      • PR interval: The PR interval is prolonged and delayed, indicating slower transit of the electrical impulse from the SA node through the AV node.
      • QRS: The QRS often widens with hyperkalemia
      • T waves: Tall peaked “tented Ts” are common with hyperkalemia.

      Whenever there are ECG changes, the treatment for hyperkalemia becomes even more essential, as patients with ECG changes are more likely to experience deadly arrhythmias.

      The ECG changes seen on the PQRST with hyperkalemia, which includes P wave flattening, PR prolongation, QRS widening, and Tented or peaked T waves

      Want to learn more?

      If you want to learn more, I have a complete video course “ECG Rhythm Master”, made specifically for nurses which goes into so much more depth and detail.

      With this course you will be able to:

      • Identify all cardiac rhythms inside and out
      • Understand the pathophysiology of why and how arrhythmias occur
      • Learn how to manage arrhythmias like an expert nurse
      • Become proficient with emergency procedures like transcutaneous pacing, defibrillation, synchronized shock, and more!

      I also include some great free bonuses with the course, including:

      • ECG Rhythm Guide eBook (190 pages!)
      • Code Cart Med Guide (code cart medication guide)
      • Code STEMI (recognizing STEMI on an EKG)

      Check out more about the course here!

      In conclusion, nurses should have an essential understanding of electrolyte abnormalities and the treatment for hyperkalemia.

      Through medications that protect the patient from cardiac arrhythmias (like calcium), medications that shift potassium into cells temporarily (like insulin, albuterol, or sodium bicarb), and treatments for hyperkalemia that remove potassium from the body (like Lasix, Kayexalate, or dialysis), we can successfully reduce our patient’s potassium and save their lives!

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      If you’d like to download this article in PDF form, click here!

      Nursing Interventions for Hypokalemia: A Comprehensive Guide for Nurses

      Nursing Interventions for Hypokalemia: A Comprehensive Guide for Nurses

      Published: March 12, 2023

      Last Updated: March 22, 2023

      William Kelly, MSN, FNP-C

      Author | Nurse Practitioner

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      A picture of a half-eaten banana and an IV bag of potassium chloride

      Hypokalemia is when the body has low potassium levels outside the cell (in the bloodstream). Potassium is an electrolyte that plays a vital role in many bodily functions, particularly in the heart and cardiovascular system. Therefore, it is essential for the proper functioning of the body, and when potassium levels are high or low, this can cause our patients to be very sick and can even cause death. 

       As a nurse, it’s essential to be aware of the signs and symptoms of hypokalemia and the nursing interventions and low-potassium treatments that can be used to manage this condition. In this article, we’ll explore the symptoms of hypokalemia, nursing interventions that can be used to address low potassium levels, and effective treatment options for patients with this condition.

      WHY IS POTASSIUM SO IMPORTANT IN THE BODY

      Electrolytes help our bodies perform daily functions and survive. Without potassium or our other electrolytes, we literally couldn’t survive.

      Electrolytes are ions with a positive or negative charge, and these help cells create energy, conduct impulses, and do what they need to do. Potassium is positively charged. Some of the functions that potassium helps regulate in the body include:

      A muscle with red electric bolts indicating pain

      Muscle Function

      Potassium is essential for proper muscle function, including both skeletal and smooth muscle. It helps the muscles contract and relaxes, impacting movement, digestion, and much more!

      A kidney with low fluid levels

      Fluid Balance

      Potassium is essential in regulating fluid balance within the body. Potassium has the same tonicity as sodium, drawing water with it wherever it goes. Potassium is essential in the movement of fluid across cell membranes.

      An emoji of the heart

      Cardiac System

      Probably one of potassium’s most essential functions, it helps the cardiac system function! The heart uses conductive tissue, which uses potassium to help transmit its signal for every heartbeat – just like it uses calcium, magnesium, and sodium as well!

      A glucometer which reads "HIGH" indicating hyperglycemia

      Blood Sugar Control

      Studies show that high-potassium diets can help improve insulin sensitivity and reduce the risk of type 2 diabetes.

      A brain with yellow connecting lights which indicate the central nervous sytem

      Nervous System

      Just like our heart, the nervous system is ALL about conducting electricity and “action potentials,” but on a much more complex level. Potassium helps our nerve cells communicate with each other.

      A normal human cell

      Cellular Function

      This is a catch-all, but the sodium-potassium pump is essential for the proper function of almost every cell in our body. That’s how vital potassium is and how hypokalemia can affect our patient’s health!

      How Is Potassium Regulated In The Body?

      The body regulates potassium in many ways to maintain it at the appropriate level to help it maintain homeostasis and function at its optimal capacity. Nurses should be aware of these mechanisms and take proper steps to monitor and maintain healthy potassium levels in their patients, particularly those with conditions that may affect potassium balance, such as kidney disease or heart disease.

      Some of the ways the body regulates potassium and prevents hypokalemia include:

      The kidneys, with the left one transected so you can see the inside

      The kidneys

      The kidneys play a crucial role in regulating potassium levels. These filter out excess potassium and retain more potassium when levels are low.

      A vial of insulin

      Hormones

      Several hormones impact potassium levels, primarily Aldosterone and Insulin.

      Aldosterone, produced by the adrenal glands, is a signal that tells the kidneys to retain more sodium and potassium.

      Insulin, which is produced by the pancreas, helps to promote the uptake of potassium into the cells.

      A liquid drop with "H+" indicating acid or acidity or hydrogen ions

      Acidity

      The body’s acidity can also affect potassium levels, with acidosis causing potassium to move out of the cells into the bloodstream and interstitial spaces.

      A normal banana unopened

      Diet

      Dietary potassium intake is essential in helping the body maintain adequate potassium levels; however not as important as you might think since the body is good at keeping extra potassium if dietary intake is inadequate. 

      Potassium levels and Acidotic States

      Remember that severely acidotic states, like that in DKA, leave the body with significant decreases in potassium. There is a LACK of insulin, which normally moves potassium into cells, and then there is also acidosis which further shifts potassium out of cells. That’s why it is SO important to replace potassium FIRST before insulin (if low). Read more about DKA here!

      Hypokalemia And Normal Potassium Levels

      Normal Potassium Levels

      • Normal = 3.5 – 5.0 mEq/L
      • Mild Hypokalemia: 3.0 – 3.5 mEq/L
      • Moderate Hypokalemia: 2.5 – 3.0 mEq/L
      • Severe Hypokalemia: < 2.5 mEq/L

      The lower the potassium level, the more likely your patient will experience side effects or complications from hypokalemia.

      Remember that this is the level of potassium that is OUTSIDE the cells of the body. The actual amount  of potassium that is outside the cell normally is very low. The inside of the cell as approximately 120-150mEq/L… That’s 30 times the level from the outside!

      This is why conditions that dramatically shift the potassium outside the cells (like DKA) can lead to a massive depletion of potassium. This is also why replacing potassium is SO important in these instances before fixing the acidosis and the hyperglycemia.

      Causes Of Hypokalemia:

      As we’ve discussed, many factors impact how the body regulates potassium levels, and similarly, there are various causes of hypokalemia. These include:

      An animal cell with arrows pointing in and out of the cell membrane, indicating redistribution of potassium across the cell membrane

      Redistribution

      Certain medications and conditions can shift potassium into the cells, which can cause low potassium levels. This includes Insulin, inhalers like albuterol, and alkalosis.

      The colon with liquid diarrhea dripping out

      GI Losses

      A common cause of hypokalemia is when it is lost from the GI system. This is usually from either excessive vomiting, diarrhea, or tube drainage.

      There isn’t a ton of potassium in the emesis, but excessive vomiting leads to increased potassium wasting in the urine.

      Renal Losses

      This is when potassium is lost in the urine and is often caused by diuretics like LOOP diuretics (Lasix) or increased mineralocorticoid activity (like hyperaldosteronism, crushing’s syndrome, etc.).

      A half-eaten banana, indicating low potassium levels

      Decreased Intake

      Often, this is not the only cause, as the body is pretty good about compensating for inadequate dietary intake.

      Nursing Assessment Of Hypokalemia

      Symptoms

      Symptoms of hypokalemia will vary depending on the patient and how severe the hypokalemia is. Still, the lower it is, the more likely the patient will exhibit symptoms, and the worse they often are.

      Some possible symptoms of hypokalemia or low potassium include:

      A weak arm with no muscle, indicating muscle weakness

      Muscle Weakness

      Muscle weakness is one of the most common symptoms of hypokalemia, which can affect the legs, arms, chest muscles, or any muscle in the body. The patient may have trouble walking, taking the stairs, or lifting objects. This usually only occurs if levels drop below 2.5 mEq/L.

      A muscle with red electric bolts indicating pain

      Muscle Cramps & Rhabdo

      Severe hypokalemia can lead to muscle cramps and even a buildup of myoglobin, leading to rhabdomyolysis. This can be damaging to the kidneys. Hypokalemia also leads to decreased perfusion of the muscles during exercise, which can worsen rhabdo.

      A battery symbol which is low

      Fatigue

      A generally non-specific symptom, but patients with low potassium often experience fatigue.

      The colon with liquid diarrhea dripping out

      GI Symptoms

      Hypokalemia can cause ileus and constipation and lead to abdominal distention, nausea, and vomiting. The patient may have diarrhea which may contribute to the hypokalemia, but can also have constipation from hypokalemia.

      A hand with blue electric bolts indicating tingling

      Paresthesias

      Hypokalemia can cause numbness and tingling in the hands or feet.

      A bladder full of urine

      Polyuria

      Low potassium can cause the kidneys to produce more urine, leading to increased urination.

      Shortness of Breath

      This is usually only in severe cases with severe muscle fatigue of the respiratory muscles, and the patient may even need to be intubated.

      A vector of a heart with a ventricular fibrillation arrhythmia with three "!" indicating seriousness

      Cardiac Arrhythmias

      Abnormalities such as premature beats (PAC, PVC), Afib, sinus bradycardia, or even VTACH or VFIB or asystole/PEA.

      Risk Factors for Hypokalemia

      Even still, most patients with low potassium on blood work will not have any specific symptoms. Certain patients have an increased risk for potassium issues. This includes:

      • CKD: Chronic kidney disease can lead to the inability to regulate potassium levels efficiently
      • Diabetes: Especially with hyperglycemia, osmotic diuresis can occur, which also causes potassium losses.
      • GI disorders: Certain GI disorders like chronic diarrhea or vomiting can lead to potassium losses
      • Alcoholism: Excessive alcohol intake can lead to decreased potassium intake and increased urinary losses
      • Patients on Diuretics: Patients on Diuretics, such as those with hypertension or CHF, are at increased risk of developing hypokalemia.

       

      A bottle of medications that are prescription

      Medications that Can Cause Hypokalemia

      • Diuretics: These increase urinary output and lead to potassium loss in the urine (Furosemide, hydrochlorothiazide, Metalozone, etc.)
      • Corticosteroids: These also cause urinary potassium loss and decrease potassium absorption
      • Beta-agonists: This shifts potassium into the cells, leading to lower levels outside the cells. It tends to be temporary.
      • Insulin: Also shifts potassium into the cells as discussed above.

      PHYSICAL EXAM

      The physical assessment of a patient with hypokalemia will depend on the severity of the potassium and other factors as well, but most patients will have no specific physical findings. 

      Vital Signs

      • HR: May be fast or low depending on cardiac arrhythmias present
      • BP: Largely unaffected, but hypokalemia can increase the risk of hypertension
      • Respirations: usually normal, but may be decreased in severe cases that cause paralysis
      • SPO2: Usually normal unless respiratory failure
      • Temp: Normal

      Inspection

      • Signs of muscle weakness, such as difficulty walking or moving
      • Signs of fatigue or lethargy

      Auscultation

      • Listen for irregular heart rhythm, which may be caused by ectopy or arrhythmia from the hypokalemia
      a gloved hand palpating unspecified skin

      Palpation

      • Muscle tenderness may be from hypokalemia.
      • Edema or ascites, which may indicate underlying kidney or liver failure that can cause hypokalemia
      • Abdominal tenderness, which can indicate GI issues that may be leading to hypokalemia

      Treatment of Hypokalemia

      Treatment of hypokalemia depends on the severity of the hypokalemia and any symptoms or complications present.

      Nursing Interventions:

      When you get your patient’s results back, and they show hypokalemia, especially < 3.0 mEq/L, then follow the following general interventions:

      Assess the Patient

      Make sure they don’t have any symptoms and are stable, including a recent set of vital signs.

      Cardiac Monitor

      Make sure your patient is on the cardiac monitor. Obtain an ECG if it still hasn’t been done.

      Notify the Provider

      Notify the provider of the potassium levels, your assessment, and their cardiac rhythm.

      Ensure IV access

      Make sure there is at least one IV site that is working well. If the level is severely low, it is best to place a second line as well.

      Evaluate Medications

      Evaluate if they are on any medications which may lead to hypokalemia, listed above.

      Administer Replacement

      Administer treatment as ordered: Administer PO or IV potassium as ordered.

      Treatment for Hypokalemia

      The treatment of hypokalemia will depend on how severe the level is low and if the patient has any significant symptoms. This will be ordered by the patient’s Provider team. Treatment generally includes:

      A kidney with low fluid levels

      Address Underlying Causes

      Identifying and addressing the underlying causes of hypokalemia is critical before correcting the potassium. The potassium may not be low but has shifted into the cells from something like alkalosis, hypothermia, and certain medications.

      Magnesium with low fluid levels with surround foods that are high in magnesium

      Correct Hypomagnesemia

      Low magnesium can cause potassium wasting in the kidneys. This means the magnesium level should be evaluated in all patients with hypokalemia and replaced first (assuming the patient is stable).

      Potassium PO pills (K-dur) potassium chloride

      Oral Potassium (PO)

      We need to replace potassium, and a large amount of potassium can be absorbed by the GI system. How much is ordered will depend on the severity of the hypokalemia.

      • Mild to moderate hypokalemia = 10-20mEq of potassium given 2-4x/day
      • severe hypokalemia or severe symptoms = Doses up to 40mEq 3-4x/day in ADDITION to IV potassium
      An IV bag of KCL

      IV Potassium (IV)

      You are limited in how fast you can infuse potassium through the IV to prevent arrhythmias and IV site irritation. Rates can be faster in a central line and slower in a peripheral IV line.

      • Mild to Moderate hypokalemia: typically not needed, and PO is fine, but if the patient is NPO, then IV can be given. Through a peripheral line, 10mEq “K-riders” are usually ordered, and you can expect the potassium to increase by ~0.1 mEq per K-rider.
      • Severe hypokalemia: In extreme cases, can give 20mEq every 2-3 hours

      IV Potassium Infusion Rates

      Where your potassium is infusing will change how fast you can infuse. While this may vary based on your specific facility protocol, generally, you can infuse in a peripheral line up to 10 mEq/L over 1 hour and in a central line 20 mEq/L over 1 hour.

      However, rates of up to 40 mEq/L can be appropriate in critical and code situations. Again, this should be infused into a central line or multiple peripheral IVs.

      Monitoring for Hypokalemia

      Patients with hypokalemia need good monitoring, especially if they have moderate to severe hypokalemia.

      A Gold top blood vial filled with blood

      Potassium Levels

      Potassium levels will be redrawn and assessed depending on the severity and what the Provider orders. Generally, mild hypokalemia is often only rechecked on the next lab draw (usually by the following day). Severe hypokalemia being replaced is recommended to be checked every 2-4 hours (usually in the ICU).

      Cardiac Rhythm

      As we’ve discussed, low potassium levels can impact cardiac rhythms, and whenever a patient’s getting IV replacement of potassium or magnesium, they should be on a cardiac monitor to monitor for cardiac ectopy or arrhythmias.

      Respiratory Function

      Severe hypokalemia can cause respiratory failure, so monitoring their breathing, lung sounds, respiratory rate, and pulse ox is essential.

      A picture of an IV that is dressed in the forearm

      IV Site

      Monitoring for phlebitis and thrombophlebitis at the insertion site is essential, as IV potassium often burns.

      IV KCL Burns

      If you are running IV potassium alone through an IV, this will often burn the patient. Applying ice packs can help, but your best bet is running fluids slowly and piggybacking the IV potassium into the Y site above, diluting the potassium. And, of course, you should have an order for these IV fluids!

      Hypokalemia and Cardiac Arrhythmias

      Potassium is super important in the proper conduction of cardiac tissue. Remember that each heartbeat involves rapid depolarization (firing) and repolarization of cardiac conductive cells.

      Potassium plays a crucial role in maintaining the resting membrane potential and regulating the overall electrical activity of the heart.

      The more common arrhythmias associated with hypokalemia include:

      • Premature Ventricular contractions (or ventricular premature beats VPBs)
      • Ventricular tachycardia (VTACH or VT). 

      These are induced by early afterdepolarizations and triggered activity, which can be caused by hypokalemia.

      Hypokalemia can cause other arrhythmias include PACs, PJCs, AV blocks, and even Afib.

      On the ECG, hypokalemia can manifest in a few ways, including:

      • ST segment: Often can cause some ST depression
      • T wave: T wave flattening is common
      • U waves: U waves become more prominent and visible in hypokalemia. Remember, these are seen best in V4-V6.
      • QT Interval: Is prolonged with hypokalemia.

      The risk of hypokalemic-induced arrhythmias is highest in elderly patients, those with heart disease, and patients on digoxin or antiarrhythmic drugs who are already predisposed to arrhythmias.

      Want to learn more?

      If you want to learn more, I have a complete video course “ECG Rhythm Master”, made specifically for nurses which goes into so much more depth and detail.

      With this course you will be able to:

      • Identify all cardiac rhythms inside and out
      • Understand the pathophysiology of why and how arrhythmias occur
      • Learn how to manage arrhythmias like an expert nurse
      • Become proficient with emergency procedures like transcutaneous pacing, defibrillation, synchronized shock, and more!

      I also include some great free bonuses with the course, including:

      • ECG Rhythm Guide eBook (190 pages!)
      • Code Cart Med Guide (code cart medication guide)
      • Code STEMI (recognizing STEMI on an EKG)

      Check out more about the course here!

      In conclusion, potassium is an essential electrolyte that plays a vital role in many bodily functions, including muscle function, fluid balance, cardiac and nervous systems, blood sugar control, and cellular function.

      Nurses must be aware of the signs and symptoms of hypokalemia and the nursing interventions and low-potassium treatments that can be used to manage this condition.

      Patients with hypokalemia require careful monitoring, especially with moderate-to-severe hypokalemia, with careful attention to their cardiac rhythm and respiratory function!

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      If you’d like to download this article in PDF form, click here!

      AFIB RVR on EKG: Management of Atrial Fibrillation

      AFIB RVR on EKG: Management of Atrial Fibrillation

      Published: April 13, 2022

      Last Updated: March 23, 2023

      William Kelly, MSN, FNP-C

      Author | Nurse Practitioner

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      Atrial Fibrillation (AFIB) and AFIB RVR are common conditions that you’ll see as a nurse within both inpatient and outpatient settings. These patients are often asymptomatic, but may have severe symptoms and even be unstable, especially with AFIB RVR.

      Recognizing AFIB on the monitor/EKG and knowing how to treat it is important as the nurse, as you’ll be on the front line with these patients!

      AFIB RVR Atrial Fibrillation Featured Image-min

      What is Atrial Fibrillation (AFIB)?

      Atrial Fibrillation (AF or AFIB) is an “irregularly irregular” arrhythmia that usually occurs in a structurally diseased heart.

      AFIB occurs when too many atrial impulses are usually coming from the pulmonary veins, causing rapid fibrillation or “quivering” of both the left and right atria.

      Remember, the heart has four chambers: left and right atria on the top and left and right ventricle on the bottom. With AFIB, the top chambers are in a constant state of fibrillation.

      During a normal heartbeat, the atria first contract, pushing blood into the ventricles, and the ventricles then pump the blood to the rest of the body. In AFIB, the atria lose this “atrial kick,” leading to ineffective atrial filling and decreased cardiac output, especially at rapid rates.

      Cardiac Conduction Review

      It is helpful to remember how the cardiac conductions system works to understand what is going on with AFIB.

      Remember, the heart has specific electrical conduction tissue, which creates and moves the electrical signal throughout the heart to produce an organized rhythm. This organization lets the heart fill and pump effectively.

      Cardiac Conduction System: AFIB RVRThe heart’s pacemaker is the sinus node located in the right atrium. This region of cells creates the “normal” impulse and sends it throughout the atria and then through the AV node. This AV node normally slows the conduction to allow for ventricular filling. The PR interval on the EKG denotes this slowing of the conduction.

      Once traveling through the AV node, the impulse goes through the Bundle of His. It splits down the left and right bundle branches towards each ventricle, then through the Purkinje fibers and eventually the ventricles, causing a heartbeat.

      In AFIB, rapid-firing comes from the atria, usually where the pulmonary veins meet the left atria. This leads to the quivering of both atria and ineffective atrial filling and atrial kick.

      While the AV node does slow down conduction, it can only do so much on its own. With such rapid firing from the atria, many of these impulses want to make it down to the ventricles and cause heartbeats.

      As you can imagine, this can lead to very fast heart rates – what we call AFIB RVR or rapid ventricular response.

      What is AFIB RVR?

      AFIB RVR (Rapid Ventricular Response) occurs due to the frequent electrical impulses from the atria.

      The AV node is only able to slow the frequent electrical impulses down so much, so many of the impulses are conducted through to the ventricles, leading to a rapid ventricular response or a fast heart rate >100bpm and often much faster.

      Patients with these fast rates are often symptomatic and may become hypotensive. These patients will usually require IV medications to slow down their rate, and possibly even electrical cardioversion (more on that later!).

      What causes AFIB?

      AFIB usually occurs in predisposed hearts and is often set off by reversible triggers.

      Chronic diseases which predispose the heart to AFIB include:

      Atrial Enlargement

      Anything causing atrial enlargement such as CHF, Cardiomyopathy, COPD, OSA, obesity

      Valvular Heart Disease

      Rheumatic Fever, aortic stenosis, valve repelacements, etc

      Ischemic Heart Disease

      Coronary artery disease, past or current myocardial infarctions (heart attacks!)

      Usually, some reversible trigger throws the patient into AFIB. These reversible triggers include:

      Surgical Procedures

      CABG or heart transplants, usually within the first 2 weeks postop

      Pulmonary Emblolisms

      PEs can cause right atrial heart strain and Increased pulmonary vascular resistance

      Alcohol

      Alcoholics and binge-drinking can cause Holiday Heart syndrome, which can occur in 60% of binge drinkers

      Drugs

      Cocaine and amphetamines can increase sympathetic tone and leave the heart predisposed to arrhythmias such as AFIB

      Hyperthyroidism

      Hyperthyroidism (low TSH) can cause increased sympathetic tone and lead to arrhythmias

      Hypomagnesemia

      Low magnesium levels can lead to AFIB, generally levels < 1.5 (check this).

      Medications

      Certain medications can trigger AFIB including Theophylline and adenosine.

      Caffeine

      Although caffeine is often thought of as contributory to ectopy and AFIB, there is no direct evidence it does trigger AF. However, it is something to consider.

      Nursing Assessment of AFIB RVR

      Symptoms of AFIB

      Up to 44% of patients with Afib are asymptomatic. Patients with faster rates are more likely to develop symptoms, and those with CHF are more likely to experience hemodynamic instability and severe symptoms (aka low BP and possible code situation).

      Some symptoms of AFIB can include:

      Fatigue

      Most common complaint

      Dypnea

      Shortness of breath

      Diaphoresis

      Sweating

      Dizziness

      Dizziness or lightheadedness

      Palpitations

      Fluttering or skipping in their chest, or possibly just feeling their heart pounding

      Chest Pain

      Chest pressure, pain, or discomfort

      Syncope

      Loss of consciousness

      The Physical Exam

      Inspection

      • Pallor or flushed
      • Diaphoresis
        • May appear tachypneic

        Vital Signs

        • BP: May be low at fast rates and with poor cardiac output
        • Pulse/HR: Often >100 (RVR)
        • Respirations: Normal or increased
        • SPO2: Usually normal

        Auscultation

        • Lungs
          • Usually Normal
          • May have crackles if CHF
        • Heart
          • Rapid and irregular rate

        Identifying AFIB RVR on the ECG

        Atrial fibrillation (AFIB RVR)

        AFIB will NOT have visible P waves. Instead, there will be a fibrillatory baseline. There is no depolarization wave throughout the atria, but rather rapid twitching and many “small” depolarizations, firing at rates 350-600 times per minute.

        The QRS complex should be narrow unless an underlying intraventricular conduction delay is present, such as a bundle branch block.

        The T waves may be difficult to decipher between the F-wave baseline completely. T wave abnormalities are common, including T wave flattening.

        AFIB is irregularly irregular. This means that the R-R interval is continuously changing, and there is no pattern.

        AFIB can be at any rate, but faster than 100 is considered AFIB RVR. Without medications to slow it down, rates are usually between 90-170 bpm.

        AFIB: Atrial Fibrillation Notes

        Initial Nursing Interventions

        STAT EKG

        Any patient with cardiac symptoms should get an EKG.

        Patients with new AFIB should have a 12-lead EKG to confirm the diagnosis.

        If the patient is at significant fast rates, keep them hooked up to grab another one once the rate improves or the patient converts.

        Cardiac Monitoring

        Patients with any cardiac symptoms should be placed on the cardiac monitor.

        Those patients with a history of AFIB with normal rates does not necessarily need a cardiac monitor.

        Oxygen Support

        If the patient is significantly hypoxic or tachypneic, apply 2-4 L/min NC to maintain SPO2 >90%.

        IV Access

        Start two peripheral IVs at least 22g, but preferably one at least 20g. If they are in AFIB RVR, they will likely need an IV Cardizem drip and IV heparin in separate lines.

        If there is a concern for pulmonary embolism or embolic stroke, make sure to place an 18-20g in the AC.

        While drawing blood, make sure to draw a blue top as PT/INR, PTT, and a D-dimer may be ordered.

        Unstable Tachyarrhythmia

        Remember that any unstable tachyarrhythmia should follow ACLS guidelines. This means the patient may need electrically cardioverted. If they are unstable (Low BP, impending arrest), then place the defibrillation pads on the patient and hook them up to the defibrillator.

        Workup for AFIB RVR

        The workup will depend if the patient is in new-onset AF or already has chronic AF and if they are in RVR or not.

        Patients with a known history of AFIB who have controlled rates don’t need any specific testing. They are usually on chronic medications to control their heart rates and anticoagulants to prevent blood clots.

        Patients with new AFIB or AFIB RVR require more extensive testing, and the workup may depend on their symptoms.

        General workup for new AFIB includes:

        12-lead ECG

        AFIB can be diagnosed with this, as well as to look for any other abnormalities such as a STEMI

        Basic Labs

        CBC, CMP, and magnesium will often be checked

        Additional Labs

        Coag studies such as PT/INR and PTT, BNP if s/s of heart failure, digoxin level if patient is taking, and a D-dimer may be ordered as well

        CXR

        If they have any cardiac or pulmonary complaints this should be obtained

        CTA

        If there is suspicion of a PE. It May also detect atrial thrombi but is not very sensitive

        CT head

        If any altered mental status or stroke-like s/s

        Complications of AFIB

        So why do we even care about AFIB? Well, there can be disastrous consequences if we do not treat it appropriately.

        Unstable Symptoms

        Patients with AFIB have an inadequate atrial filling of blood, as well a loss of the atrial kick which pushes blood from the atria to the ventricles. This decreases cardiac output. When the ventricles have a rapid response, these insufficiencies worsen and can lead to hemodynamic compromise – hypotension, hypoxemia, and eventually cardiac arrest.

        Worsened CHF

        Patients with Left ventricular dysfunction (aka CHF with a low EF) already have a weak heart. This drop in cardiac output will be more significant, often leading to severe symptoms and an unstable patient!

        Blood Clots

        With the atria quivering – stasis of blood occurs. Remember, stasis of blood is one of the 3 factors that can lead to blood clots (Virchow’s triad). This increases the likelihood of thrombus formation.

        A thrombus in the right atria can embolize to the lungs and cause a pulmonary embolism, and a left atrial thrombus can embolize to the brain and cause an embolic stroke.

        Both of these are very serious conditions which can lead to disability and death, so prevention of this complication is important.

        Treatment of AFIB RVR

        Treatment of AFIB differs and depends on the patient’s symptoms and quality of life. This will involve at least one, but possibly all three of the following:

        • Rate control: Control the heart rate with AFIB (preventing RVR)
        • Rhythm Control: Convert and maintain the patient in a normal sinus rhythm
        • Anticoagulation: Giving blood thinners to prevent blood clot formation within the atria

        Which the Provider team and Cardiology will ultimately choose treatment options. We’ll dive a little deeper into each of these treatment options.

        Rate Control

        Rate-control is achieved via medications to slow down the ventricular response to the AFIB. Common medications include Metoprolol, Diltiazem, Digoxin, Esmolol, Amiodarone, and even magnesium sulfate.

        For AFIB RVR, we often give the following medications to control the rate:

        IV Diltiazem

        Also called Cardizem, this is more commonly given for AFIB RVR. The dose is 0.25mg/kg bolus, which is usually around 20mg. This should be pushed over 2 minutes. A repeat bolus of 0.35mg/kg can be given in 15 minutes if rate control is insufficient, and then a patient should be started on a titratable Cardizem drip.

        IV Metoprolol

        Also called Lopressor, this is especially helpful if the patient is on a Beta-blocker at home and maybe has missed some doses. The dose is 2.5-5mg IV q5m x 3. Administer the IV push over 2 minutes, and monitor rhythm and blood pressure closely. Use with caution with asthma/COPD exacerbations.

        Low BP & RVR

        One thing to point out is that those patients with significant left ventricular heart failure and AF RVR may paradoxically improve their blood pressure with rate control, so it still may be wise to administer a low dose of metoprolol or cardizem in these select patients if borderline hypotension is present. Always verify with the Physician/APP.

        Rhythm Control

        Rhythm-control is achieved via medications or electrical cardioversion. If the patient is unstable, they will be electrically cardioverted. Otherwise, the cardiologist may choose to start the patient on an antiarrhythmic such as amiodarone, Flecainide, multaq, etc.

        Many elderly patients who do not have significant symptoms will not undergo rhythm control. This is ultimately up to the cardiologist.

        Chemical Cardioversion

        IV amiodarone can be used, or the cardiologist may choose to start an oral antiarrhythmic such as Amiodarone, Sotalol, Dofetilide, etc

        Electrical Cardioversion

        Unstable patients should undergo synchronized cardioversion with the defibrillator

        Radiofrequency Ablation

        Patients with frequent symptoms (often younger patients) may undergo an ablation to burn off the area of the heart that is triggering AFIB

        Anticoagulation

        Anticoagulation is almost always used in patients with AFIB, unless there is acute bleeding or a significant risk of bleeding.

        Anticoagulation is used to prevent thrombus formation which can cause PEs and Strokes as explained above. Within the hospital, anticoagulation will include either:

        Heparin Drip

        The Provider will order a titratable heparin drip per facility protocol. This usually will have an initial bolus ordered as well. The patient’s PTT will occasionally be checked and the drip will be adjusted accordingly. Heparin drips offer quickly-reversible anticoagulation in case the patient starts bleeding.

        SubQ Lovenox

        SubQ lovenox at a dose of 1mg/kg BID can be given alternatively.

        Before being discharged, the patient is then transitioned onto an oral anticoagulant such as coumadin, Eliquis, Xarelto, Pradaxa, or ASA/Plavix.

        Coumadin

        Coumadin is much less commonly prescribed than it used to be because it requires frequent blood checks of INR, as well as dietary changes and medications, can significantly impact its therapeutic levels

        The CHADSVASC score is used to gauge risk for thrombus formation, which factors in age, sex, h/o CHF, HTN, Stroke/TIA/DVT/PE, Vascular disease, or Diabetes. If the patient does not have a high risk of bleeding such as intracranial bleeding, GIB, or frequent falls, then they are usually started on an anticoagulant.

        Clinical Pearls

        Patient Specific

        The workup and treatment will depend on the patient’s symptoms and overall clinical picture. With AFIB, there is no one-size-fits-all approach!

        AFIB RVR

        Focus on rate control and anticoagulation! Become familiar with IV Cardizem and titrating a Cardizem drip, as well as IV Lopressor!

        Unstable = Shock

        Patients who are unstable should be electrically cardioverted with a synchronized shock. Remember to press SYNC, and the dose is 50-100J. These patients will require sedation and pain control (i.e. IV fentanyl).

        Want to learn more?

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        REFERENCES

        Burns, E. (2021). Atrial Fibrillation. In ECG Library. Retrieved from https://litfl.com/atrial-fibrillation-ecg-library/

        Kumar, K. (2022). Overview of atrial fibrillation. In T. W. Post (Ed.), UpToDate. Retrieved from https://www.uptodate.com/contents/overview-of-atrial-fibrillation

        Olshansky, B. (2022). The electrocardiogram in atrial fibrillation. In T. W. Post (Ed.), UpToDate. Retrieved from https://www.uptodate.com/contents/the-electrocardiogram-inatrial-fibrillation

        Phang, R., Prutkin, J. M., Ganz, L. I. (2022). Overview of atrial flutter. In T. W. Post (Ed.), UpToDate. Retrieved from https://www.uptodate.com/contents/overview-of-atrial-flutter

        Prutkins, J. M. (2022). Electrocardiographic and electrophysiologic features of atrial flutter. In T. W. Post (Ed.), UpToDate. Retrieved from https://www.uptodate.com/contents/electrocardiographic-and-electrophysiologic-features-of-atrial-flutter