5-unit IV insulin prevents hypoglycaemia, reduces potassium in adults with hyperkalaemia

Five-unit dosing of intravenous (IV) regular insulin results in lower hypoglycaemia incidence and comparable serum potassium decrease when compared with doses >5 units, according to a study.

A total of 896 charts were reviewed in this study, including 290 patients. Of these, 126 received 5 units and 164 received >5 units of IV regular insulin. Hypoglycaemia occurred in six patients in the 5-unit group and in 23 in the >5-unit group (4.7 percent vs 14 percent; p=0.0014). Twenty-six of 29 (90 percent) patients with hypoglycaemia had renal impairment.

Baseline (5.9 mEq/L; p=0.32) and follow-up mean potassium (5.3 mEq/L; p=0.87) was comparable between the two groups.

“Patients who received 5 units of IV regular insulin had a lower incidence of hypoglycaemia with a similar reduction in serum potassium when compared to patients who received doses greater than 5 units,” the authors said.

This single-centre, retrospective, observational, cohort study sought to examine the safety and efficacy of IV regular insulin in patients with acute hyperkalaemia. The authors included patients aged ≥18 years, who received ≥5 units of IV regular insulin, had proinsulin potassium ≥5.1 mEq/L, and blood glucose measured within 3 h before and 12 h after insulin administration.

The incidence of hypoglycaemia within 12 h of insulin administration was the primary outcome.

“IV regular insulin treats acute hyperkalaemia,” the authors said. “No guideline recommendations exist on the appropriate dose to be administered to maximize safety and efficacy.”