Introduction
Potassium is essential for numerous physiological processes of the human body. Potassium is rapidly and typically completely absorbed from the digestive tract. The typical daily intake can change depending on the diet. Fruits, potatoes, beans, and grains are common sources of potassium; in contrast, high-fat diets typically have low potassium intakes. The glomerulus filters potassium, which is then almost entirely reabsorbed in the proximal tubule and the loop of Henle and excreted through the collecting ducts of the kidneys. A rise in the potassium level due to an imbalance between intake and excretion, an abnormal distribution of the mineral between intracellular and extracellular space, or in people with healthy other regulatory systems and unimpaired renal function, or other factors is referred to as hyperkalemia. This article discusses the causes, symptoms, and treatment of hyperkalemia.
What Is Hyperkalemia?
A serum or plasma potassium level over the upper normal limits, often more than 5.0 mEq/L to 5.5 mEq/L, is referred to as hyperkalemia. Even while mild hyperkalemia is usually asymptomatic, it can cause life-threatening cardiac arrhythmias, muscle weakness, or paralysis. Pseudohyperkalemia occurs when a syringe rather than a vacuum device is used to collect the sample and is the most frequent cause of hyperkalemia. The normal range for blood potassium is 3.6 to 5.2 millimoles per liter (mmol/L). Blood potassium levels of more than 6.0 millimoles per liter can be dangerous and typically call for prompt medical attention.
What Happens if the Potassium Level Is High?
The body gets potassium through food. Usually, the kidney eliminates the extra potassium, which leaves the body as urine. If there is excessive potassium in the body, the kidney will be unable to eliminate all of it, and it will build up in the blood. Excessive potassium in the blood can result in heart issues such as vibration or even heart attacks.
What Are the Causes of Hyperkalemia?
The causes of hyperkalemia are as follows:
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Acute Kidney Failure and Chronic Kidney Disease: The kidneys remove excess potassium from the blood and excrete it in the urine. This function is breached if there is a kidney disorder. In cases of mild kidney dysfunction, the kidneys maintain the potassium level. However, in severe diseases, the kidneys cannot remove the excess potassium, and it gets stored in the blood, resulting in hyperkalemia.
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Potassium-Rich Diet: Consumption of a potassium-rich diet also increases the risk of hyperkalemia, but it is uncommon. The risk is much higher in people who, in addition, have a renal disorder. Beans, bananas, cooked spinach, mushrooms, potatoes, sweet potatoes, cucumbers, and oranges are high-potassium foods.
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Medications: Certain medications like angiotensin II receptor blockers, angiotensin-converting enzyme (ACE) inhibitors, and beta-blockers hamper the elimination of potassium from the kidney, increasing the potassium level in the blood.
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Burns: Hyperkalemia was thought to be a risk factor for patients with electrical burns. Red blood cell apoptosis, rhabdomyolysis, metabolic acidosis, and the onset of renal failure are some causes of hyperkalemia.
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Uncontrolled Diabetes: Poorly controlled diabetes directly affects kidney function, so it increases the chances of hyperkalemia.
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Congestive heart failure.
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Dehydration.
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Human immunodeficiency virus (HIV).
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Potassium supplements.
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Hormonal disorders.
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Lupus.
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Chronic alcoholism.
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Hemolysis (breakdown of red blood cells).
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Rhabdomyolysis (breakdown of muscles).
What Are the Symptoms of Hyperkalemia?
Usually, mild hyperkalemia does not manifest any symptoms. However, the hyperkalemia symptoms occur intermittently and gradually increase over time. Very high potassium levels cause severe complications, and immediate treatment is needed. Signs and symptoms of hyperkalemia include:
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Abdominal pain.
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Diarrhea.
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Chest pain.
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Palpitations.
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Irregular heartbeat.
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Fatigue and numbness in the muscles of extremities.
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Paralysis.
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Breathing difficulties.
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Signs of a heart attack include a weak pulse, chest pain, etc.
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Severe muscle fatigue.
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Severe abdominal pain.
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Nausea.
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Vomiting.
When Is Emergency Treatment Needed for Hyperkalemia?
Hyperkalemia is often accidentally diagnosed in routine blood tests since it exhibits no symptoms during the initial phases. Medical history, diet, and medications play an essential role in diagnosis. Therefore, it is necessary to inform the doctor about everything, even over-the-counter drugs, herbal medicines, or other supplements. An electrocardiogram can help diagnose any changes or abnormalities in the heart rhythm.
Hyperkalemia and Electrocardiogram (ECG): An electrocardiogram may show the following changes:
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T waves attain the peak.
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Short QT intervals.
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ST-segment depression.
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Widening of QRS complex.
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Increase in the PR interval.
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A decrease in the amplitude of the P wave.
These are the initial changes that can be reversed with treatment for hyperkalemia. If left untreated, it causes further widening of the QRS complex and the disappearance of the P wave. Ventricular fibrillation, a type of arrhythmia characterized by rapid and inadequate heartbeat, usually follows these changes. Though there is typically a correlation between the ECG changes and hyperkalemia, sometimes severe arrhythmias can occur at any stage without any distinct ECG changes.
How Can Hyperkalemia Be Treated?
Depending on the level of potassium in the blood, there are different treatment options which include:
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Diuretics: As potassium excretion mainly happens through urine, diuretics or water pills help in increasing urine flow, which eventually reduces the potassium level in the blood.
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Low-Potassium Diet: It is also advisable to follow a low-potassium diet and reduce the consumption of salt substitutes that are high in potassium. A dietitian will help create a specialized meal plan for hyperkalemia.
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Potassium Binders: This medication must be taken daily. It binds with excess potassium in the bowels and excretes it in feces. It is usually administered orally but can sometimes be administered through the rectum as an enema. For oral administration, it is mixed with water. These are recommended when other treatments do not work. Also, caution should be taken not to take the potassium binders within six hours of taking any other drugs, and it is also not recommended in children.
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Intravenous Therapy: It is the suggested treatment modality in patients who require emergency treatment, during which an intravenous infusion of calcium is done to protect the heart from further damage. In addition, Insulin is infused, which helps move potassium into the blood cells. Also, Albuterol inhalation is needed, an asthmatic drug that helps decrease potassium levels.
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Managing the Medications: Drug-induced hyperkalemia can be reversed by withdrawing anti-hypertensive medications and other drugs, which cause a significant rise in the potassium level. It is suggested to consult with the physician and change the medications taken.
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Dialysis: Suppose the potassium levels continue to rise despite the treatment, or in case of complete renal failure, it is advisable to do dialysis to lower the potassium levels in the blood.
How Can Hyperkalemia Be Prevented?
The best way to prevent hyperkalemia in hyperkalemic patients or high-risk patients with known renal dysfunctions is to limit potassium intake in food.
Conclusion
Due to the risk of cardiac arrest and severe weakness, hyperkalemia is treated by an interdisciplinary team. In most cases, the prognosis is good with an adequate diet and medications. It does not result in any long-term complications. However, people with chronic disorders like end-stage renal failure might need routine blood tests to check their potassium levels. In conclusion, it is clinically relevant and potentially life-saving to recognize and treat hyperkalemia as soon as possible, especially if renal function is compromised.
