Clinical manifestations of hyperkalemia

Written by Wei Shi Liang
Intensive Care Unit
Updated on September 04, 2024
00:00
00:00

The clinical manifestations of hyperkalemia mainly affect the cardiovascular system, often presenting with slowed heart rate and various arrhythmias. When the blood potassium level is between 6.6 and 8.0 mmol/L, a tent-shaped T-wave can be observed. Rapid increases in blood potassium can lead to ventricular tachycardia, and even ventricular fibrillation. A gradual increase in blood potassium can cause conduction blocks, and in severe cases, cardiac arrest. Sudden death in severe hyperkalemia is mainly due to ventricular fibrillation and cardiac arrest. The second aspect is symptoms related to the neuromuscular system. As the concentration of potassium ions in the extracellular fluid increases, the resting membrane potential drops, leading to muscle weakness and even paralysis, typically more pronounced in the lower limbs and extending upward along the trunk. In severe cases, some patients may experience difficulty in swallowing and breathing difficulties. Symptoms involving the central nervous system mainly include restlessness, confusion, and fainting.

Other Voices

doctor image
home-news-image
Written by Wei Shi Liang
Intensive Care Unit
57sec home-news-image

Hyperkalemia can be seen in which diseases?

Hyperkalemia is a condition where the serum potassium concentration exceeds 5.5 millimoles per liter. Common causes include excessive intake of potassium, such as high-dose potassium penicillin intravenous infusion, ingestion of potassium-containing medications, or transfusion of large amounts of stored blood, all of which can lead to hyperkalemia. Additionally, patients with renal failure who experience oliguria or anuria may have reduced potassium excretion. In such cases, inappropriate potassium supplementation or the use of potassium-sparing diuretics can lead to severe hyperkalemia. Lastly, the movement of potassium from inside the cells—during metabolic acidosis and respiratory acidosis—causes ion exchange, leading to hydrogen ions entering the cells while potassium ions leak out, resulting in hyperkalemia.

doctor image
home-news-image
Written by Yang Li
Endocrinology
51sec home-news-image

What medication is used for hyperkalemia?

Hyperkalemia is primarily treated by promoting diuresis to enhance the elimination of potassium, while calcium gluconate can also be administered intravenously to counteract the inhibitory effects of potassium on the heart. Additionally, concentrated glucose with insulin can be used to shift excess potassium ions from the blood. Sodium bicarbonate can also be used to alkalinize the blood's pH to help reduce potassium levels. All these treatments must be conducted safely. In cases of severe hyperkalemia, dialysis may be necessary. If arrhythmias, bradycardia, or myocardial depression occur, the installation of a temporary pacemaker, along with hemodialysis, may be required. (Medication should be administered under the guidance of a physician.)

doctor image
home-news-image
Written by Wei Shi Liang
Intensive Care Unit
48sec home-news-image

Common causes of hyperkalemia

Hyperkalemia is caused by increased intake or decreased excretion, or by the transfer of potassium ions from inside the cells to the outside. Increased intake generally does not cause hyperkalemia in individuals with normal kidney function, unless potassium is supplemented intravenously in excessive amounts or too quickly. Moreover, decreased excretion is a major cause of hyperkalemia, typically seen in renal failure, deficiency of adrenocortical hormones, and primary renal tubular disorders in potassium secretion. Additionally, a large transfer of potassium ions from inside the cells to the outside can occur in conditions such as massive cell breakdown, acidosis, tissue hypoxia, periodic paralysis, and insulin deficiency.

doctor image
home-news-image
Written by Wei Shi Liang
Intensive Care Unit
45sec home-news-image

How to rescue hyperkalemia

Hyperkalemia must be dealt with immediately once it occurs. The usual treatments in clinical settings include promoting potassium excretion using furosemide or other loop diuretics to maximize renal potassium excretion, or using oral or rectal potassium-eliminating agents. For life-threatening hyperkalemia with serum potassium levels greater than 6.5 mmol/L, hemodialysis is necessary. Another approach is to facilitate the shift of potassium into cells, which is done through the administration of insulin with glucose, or sodium bicarbonate along with calcium gluconate that helps protect the myocardium, thus providing treatment and protective measures for hyperkalemia.

doctor image
home-news-image
Written by Wei Shi Liang
Intensive Care Unit
1min 12sec home-news-image

What kind of urine occurs with hyperkalemia?

Primary hyperkalemia often coincides with metabolic acidosis, and in hyperkalemia-induced metabolic acidosis, paradoxical alkaline urine can occur. Once hyperkalemia occurs, it primarily affects the conduction of the heart and neuromuscular system. Typical clinical manifestations include severe bradycardia, atrioventricular conduction block, and even sinus arrest. In mild hyperkalemia, the electrocardiogram shows peaked T-waves; as potassium levels continue to rise, the PR interval prolongs, T-waves disappear, QRS complex widens, and ultimately, cardiac arrest occurs. Immediate treatment should be administered upon diagnosis to promote the excretion of potassium, maximizing the renal excretion capacity with diuretics. If drug-induced potassium excretion does not normalize levels and serum potassium exceeds 6.5 mmol/L, hemodialysis may be necessary. Additionally, some drugs can be used to shift potassium into the cells and protect cardiac function. (The use of any medication should be under the guidance of a doctor.)