Evaluation of Insulin Dosing Strategies for Hyperkalemia Management at an Academic Medical Center

While intravenous (IV) insulin is often administered at a fixed dose of 10 units for acute hyperkalemia, optimal dosing for minimizing hypoglycemia while effectively reversing hyperkalemia has not been established. The purpose of this analysis was to evaluate the effect of insulin dosing strategies on hypoglycemia in patients with hyperkalemia.

Adult patients presenting to an academic medical center who received IV insulin for hyperkalemia between 2016 and 2020 were retrospectively identified. Patients treated with 10 units of insulin (fixed) were compared to those who received < 10 units (reduced). The primary outcome was the incidence of hypoglycemia (blood glucose < 70 mg/dL) within 12 hours of insulin administration. Secondary outcomes included the incidence of severe hypoglycemia (blood glucose < 40 mg/dL) and change in potassium. Multivariable analyses were used to assess for risk factors for hypoglycemia and severe hypoglycemia.

Of the 2576 patients included, 305 (11.8%) received reduced dosing and 2271 (88.2%) received fixed dosing. Hypoglycemia occurred in 16.7% of the reduced group and 15.9% of the fixed group (P = 0.70). Severe hypoglycemia occurred in 2.3% of the reduced group and 2.5% of the fixed group (P = 0.86). Median potassium reduction from baseline to first check post-insulin was less with reduced dosing (-0.6 mEq/L vs -0.8 mEq/L, P < 0.001). On multivariable regression analysis, greater weight-based insulin dose and ED location were significant predictors for hypoglycemia and severe hypoglycemia. Location in the intensive care unit was associated with a decreased risk of hypoglycemia. Higher pre-insulin glucose was protective for hypoglycemia and severe hypoglycemia.

The incidence of hypoglycemia was similar among both groups. Greater weight-based insulin dose was a significant risk factor for hypoglycemia, while higher baseline glucose levels were associated with a decreased risk, indicating that patient-specific insulin dosing for hyperkalemia may be warranted.