Preventing hypokalemia in critically ill patients

Many therapies used in critical care cause potassium depletion. Current practice relies on potassium replacement protocols after a patient becomes hypokalemic. Potassium bolus therapy creates risk for patients, is costly, and increases nurses' workload.

To determine if administering potassium preemptively in maintenance intravenous fluid would prevent episodes of hypokalemia and reduce the need for potassium boluses.

Medical records of 267 patients with normal potassium and creatinine levels at admission who did not receive total parenteral nutrition were reviewed. The 156 patients who met the study criteria were categorized by group: those who received potassium via maintenance intravenous fluid (treatment; n = 76) and those who did not (control; n = 80). The treatment group had potassium chloride or acetate added to intravenous fluid delivered at 36 to 72 mmol/d.

The 2 groups did not differ significantly in age, race, sex, or admitting diagnosis. Type of diagnosis, length of stay, and potassium and creatinine levels at admission did not affect the number of potassium boluses for either group. The patients given maintenance potassium preemptively received significantly fewer (P < .001) potassium boluses (0.8) than did the control group (2.73), for a mean savings of $231 per patient for the treatment group.

Patients with normal potassium and creatinine levels at admission benefitted from a maintenance intravenous dose of potassium of 72 to 144 mmol/L per day. Compared with control patients, patients receiving this dose avoided detrimental hypokalemic events, had fewer invasive procedures and lower costs, and required less nursing care.