Rapid correction of hyperkalemia is associated with reduced mortality in ED patients

Hyperkalemia (HK) is common and associated with mortality. Our purpose was to determine if the rapid correction of elevated serum potassium level (K⁺) was associated with reduced mortality in emergency department (ED) patients.

Design: We reviewed the electronic medical records (EMR) of ED patients with HK (K⁺ ≥ 5.5 mEq/L) from 10/2016-10/2017.

Large, academic ED.

Adult ED patients presenting with hyperkalemia. Main outcomes and measures: The main outcome was in-hospital mortality. We compared outcomes of patients whose K⁺ normalized (dropped below 5.5 mEq/L) with those whose K⁺ did not normalize using chi-square and multivariate analyses to determine the associations between predictor variables and outcomes.

From 114,977 ED visits, 1033 patients (0.9%, 95%CI 0.85-0.95%) had HK. Their mean (SD) age was 60 (26) years and 58% were male. Of these, 884 had a second K⁺ measured within a median (IQR) of 5 (3-8) hours. Mortality and admission rates were higher in patients with HK vs. those with normal K⁺ (8.5% vs. 0.8%, P < 0.001 and 80% vs. 39%, P < 0.001, respectively). Mortality was lower in patients whose HK normalized compared with those whose K⁺ remained elevated (6.3% vs. 12.7%, P = 0.001). After adjusting for age, creatinine, comorbidities, and initial K⁺, normalization of K⁺ was associated with reduced mortality (OR 0.47, 95%CI 0.28 to 0.80).

Normalization of K⁺ during the ED stay in patients with HK is associated with a 50% mortality reduction. Efforts to rapidly identify and treat HK in the ED are needed.