Potassium is the main intracellular ion. Potassium ions play an important role in the regulation of body functions. They participate in the regulation of water-electrolyte metabolism, the carrying out and transmembrane transmission of nerve impulses, and the reduction of skeletal muscles. Introduction to the body of potassium is accompanied by activation of cytoplasmic enzymes, increased formation of proteins, acetylcholine, as well as increased adrenaline production by the adrenal glands.
The potassium content in the human serum is about 3.6 to 5.4 mmol / l.
Potassium ions act on the heart like a vagus nerve irritation. They cause a decrease in the rhythm of cardiac contractions, reduce contractile activity, oppress the automatism, excitability and conductivity of the myocardium. A relatively small increase in the potassium content in the blood leads to a decrease in the excitability and conductivity of the myocardium, and high concentrations (above 8 mmol / L) of its concentration inhibit the automatism and contractility of the heart muscle. An increase in the potassium content in the blood above 15 mmol / l leads to cardiac arrest in the diastole phase.
At low concentrations, potassium ions dilate the coronary vessels, and in large concentrations they narrow them. Reducing the concentration of potassium in the blood serum increases the risk of arrhythmias in patients who receive cardiac glycosides. Potassium ions, acting as functional antagonists of calcium ions, reduce the risk of toxic effects of cardiac glycosides on the heart. It is characteristic that potassium, being an antagonist of cardiac glycosides with respect to the influence on the rhythm of cardiac activity, does not significantly change their positive inotropic effect.
Potassium chloride has a moderate diuretic effect. The diuretic effect of the drug is associated with a change in the concentration function of the kidneys, a decrease in the reabsorption of water and sodium ions, and an increase in the amount of fluid entering the distal nephron.
- Hypokalemia (including diabetes mellitus, prolonged diarrhea, vomiting, with some diuretics (thiazide, thiazide, loop), glucocorticosteroids, cardiac glycosides) - treatment and prevention;
- digititis intoxication;
- Arrhythmias of various origin (associated with electrolyte disorders and absolute or relative hypokalemia);
- myocardial infarction (treatment and prevention of arrhythmia).
The drug is used to restore the broken ion gradient of the body's internal media. It is indicated for chronic dehydration with loss of electrolytes (chronic deficiency of electrolytes).
With hypokalemia, accompanied by heart rhythm disturbances, 20-30 ml of 7.5% solution in 500 ml of 5% glucose solution (drop in slowly!) Is injected intravenously. After restoring the heart rhythm, the dose of the drug is reduced.
Assign potassium chloride with paroxysmal tachycardia caused by electrolyte disorders.
The drug is also used in case of intoxication with cardiac glycosides (in light cases 2-3 g of potassium chloride per day, and in heavy cases, up to 5 g).