(1989; 60 pages) [French]
Group: electrolyte-replacement solution
Injectable solution: 1.5 mmol/ml in 20-ml ampoule
Potassium is the major intracellular ion. Maintenance of physiological concentrations is vital for many essential intracellular metabolic processes.
Prevention and treatment of potassium depletion during prolonged parenteral fluid therapy.
Dosage and administration
Individual requirements must be determined by clinical assessment and, whenever possible, by estimating plasma potassium concentrations, which should be maintained between 3.5 and 5 mmol/litre.
Potassium chloride solution (1.5 mmol/ml) must always be diluted before use. The normal daily requirement of 3 g (40 mmol) of potassium chloride should be thoroughly mixed in 1 litre of infusion fluid. The rate of infusion should not exceed 10 mmol/hour except in cases of severe hypokalaemia when the rate of administration may be raised to as much as 40 mmol/hour.
Electrocardiographic and electrolyte monitoring is essential. particularly at high infusion rates.
• Severe renal impairment.
• Untreated Addison’s disease.
Potassium should never be administered when the plasma concentration exceeds 5 mmol/litre. Since release of intracellular potassium from traumatized tissues results in hyperkalaemia, potassium chloride solution should not be given to patients with severe burns or crush injuries, or within 24 hours of major surgery.
An adequate urine flow must be established before potassium chloride solution is infused. Close clinical observation for signs of hyperkalaemia and, whenever possible, biochemical monitoring of plasma potassium concentrations should be continued throughout therapy.
Patients additionally receiving digitalis glycosides require particularly careful clinical and biochemical monitoring since they are at particular risk of ventricular dysrhythmias.
Hyperkalaemia can result in sudden death from cardiac dysrhythmia. Warning signs and symptoms include distal paraesthesiae, apathy, muscular weakness, listless-ness, mental confusion, cold skin and grey pallor. Cardiovascular collapse secondary to cardiac dysrhythmia or cardiac arrest is a terminal event.
Treatment of hyperkalaemia
Infusion of potassium chloride solution should be suspended immediately when there is clinical or laboratory evidence of hyperkalaemia. Glucose (50 ml of a 500 mg/ml solution) together with 5 International Units of soluble insulin should be administered intravenously to facilitate intracellular uptake of potassium. If metabolic acidosis is present, an infusion of 50 ml of 84 mg/ml sodium bicarbonate should then be given at 1 ml/minute, whenever possible under continuous cardiac monitoring. Should a potentially serious dysrhythmia develop, calcium gluconate (10 ml of a 100 mg/ml solution) should be given intravenously. This dose may be repeated at 2-minute intervals for as long as electrocardiographic abnormalities persist.
Rapid reduction of serum potassium concentrations in “digitalized” patients may induce digitalis toxicity.
Potassium chloride solution should be stored in ampoules.