What are the dangers of low blood potassium?

Potassium is a very important trace element for the human body. If the potassium content is too low, it will lead to hypokalemia, which can even cause death in severe cases. Low blood potassium is very harmful, which is reflected in many aspects, such as the digestive system, cardiovascular system, etc. We must have a full understanding of the hazards and solve them in time when low blood potassium occurs. So, what are the dangers of low blood potassium? Let’s take a look below.

Hypokalemia is defined as a serum potassium concentration less than 3.5 mmol/L. The main cause of hypokalemia may be the loss of total potassium in the body, which is called potassium deficiency; it may also be the transfer of potassium into cells or dilution due to excessive body fluids, while the total potassium in the body is not deficient. Severe hypokalemia can cause serious complications and even be life-threatening, so it requires active treatment.

The severity of potassium deficiency is closely related to the difference in potassium concentration inside and outside cells, and depends on the speed, duration and cause of hypokalemia. Hypokalemia caused by long-term use of diuretics usually develops gradually, so the clinical manifestations are not serious. Low potassium levels in a short period of time can cause sudden death. Blood pH and other blood electrolyte concentrations are also related to the severity of symptoms. When severe hypokalemia is accompanied by acidosis, the symptoms of hypokalemia can be alleviated as potassium in the cells moves to the extracellular space, such as in diabetic acidosis. However, as acidosis is corrected, potassium deficiency symptoms can rapidly worsen.

1. Digestive system

Hypokalemia can cause weakened intestinal motility. Mild cases may cause loss of appetite, nausea, and constipation. Severe hypokalemia may cause abdominal distension and paralytic ileus.

2. Cardiovascular system

When blood potassium is low, myocardial excitability generally increases, and palpitations and arrhythmias may occur. In severe cases, atrioventricular block, ventricular tachycardia and ventricular fibrillation may occur, and finally the heart stops beating in a contraction state. In addition, it can also cause decreased myocardial tension, heart enlargement, peripheral vascular dilation, and decreased blood pressure.

3. Neuromuscular system

It manifests as decreased nerve and muscle irritability, weakness of the limb muscles, flaccid paralysis, slow or absent tendon reflexes and other kidney disease symptoms. In severe cases, breathing difficulties and even coma may occur.

4. Urinary system

Long-term hypokalemia can cause potassium-deficient nephropathy and renal dysfunction, decreased renal concentrating function, polyuria with low specific gravity, especially increased nocturia. This may be due to damage to distal tubular cells, reduced response to antidiuretic hormone, and reduced water reabsorption capacity. In addition, potassium deficiency will cause the bladder smooth muscle tension to decrease, urinary retention may occur, and patients are often prone to pyelonephritis.

5. Acid-base balance disorder

Hypokalemia can lead to metabolic alkali poisoning.