Conventional dose still better than reduced dose insulin for hyperkalaemia

A recent study has shown that conventional dose insulin remains more effective than reduced dose regular insulin at baseline serum potassium levels >6 mmol/L in the treatment of hyperkalaemia.

“Using a reduced dose of 5 units of regular insulin has been proposed as a strategy to mitigate the risk of hypoglycaemia when treating hyperkalaemia,” according to the authors.

This study compared the effectiveness of reduced vs conventional dosed insulin for hyperkalaemia treatment. The authors reviewed electronic medication administration reports of conventional or reduced doses of insulin given to patients from July 2013 to September 2015. Reduction in serum potassium was the primary outcome.

A total of 92 administrations of reduced dose insulin and 309 administrations of conventional dose insulin were included in the review. There was no significant difference in potassium reduction between the two treatment groups (–0.096 mmol/L; p=0.2210).

In posthoc subgroup analysis of patients with serum potassium >6 mmol/L, results showed a lower decrease in potassium in the reduced dose insulin group compared to the conventional dose insulin group (difference, –0.238 mmol/L; p=0.018).

“Frequent monitoring of serum potassium and glucose after administration of insulin is necessary to confirm adequate response and avoidance of hypoglycaemia,” the authors said.

In contrast, a 2017 study reported that 5 units of insulin reduced serum potassium to the same extent as 10 units of insulin in patients with renal insufficiency and hyperkalaemia, but with a lower hypoglycaemia rate. [Pharmacotherapy 2017;37:1516-1522]