Evaluation of the safety and efficacy of the central venous administration of potassium chloride including the measurement of intracardiac potassium concentrations

Abstract

This study examined the safety and efficacy of the intravenous administration of 20 mEq potassium chloride (KCl) dissolved in a 100 cc 5% dextrose in sterile water bolus over 1 hour through a subclavian central vein catheter in critical care unit patients for the treatment of low and low to normal serum potassium concentrations. We studied seven patients with morning serum potassium between 2.4 and 3.6 mEq/L who had intravenous KCl boluses ordered by their treating physician. Intracardiac and peripheral venous potassium levels were obtained before, during, and after infusion. Holter and electrocardiogram assessment of rhythm, supraventricular and ventricular ectopy, and electrical intervals were recorded before, during, and after the intravenous KCl bolus. The cardiac rhythm, heart rates, and electrocardiographic intervals remained unchanged throughout the infusion and postinfusion phases. In six of the seven patients, there was no new or worsening supraventricular or ventricular ectopy temporally related to the infusion. Postinfusion potassium levels increased in all patients, with an average peripheral vein serum potassium increase of 0.4 mEq/L. In conclusion, within the limitations of our sample size, our study demonstrated the safety and efficacy of the central venous infusion of 20 mEq KCl in 100 cc 5% dextrose in sterile water administered over 1 hour.

Keywords: Central administration of potassium; hypokalemia; intracardiac potassium; potassium infusion.

Figure 1.

Study design schematic illustrating periods of the potassium infusion and Holter monitoring and the temporal sequence of the electrocardiographic recordings and potassium samplings.