Davis J, Israni R, Betts KA, Mu F, Cook EE, Anzalone D, Szerlip H, Yin L, Uwaifo GI, Wu EQ
Introduction Hyperkalemia is often managed in the emergency department (ED) and it is important to understand how ED management and post-discharge outcomes vary by hyperkalemia severity. This study was conducted to characterize ED management and post-discharge outcomes across hyperkalemia severities. Methods Adults with an ED visit with hyperkalemia (at least one serum potassium lab measure above 5.0 mEq/L) were selected from US electronic medical record data (2012-2018). Patient characteristics, potassium levels, treatments, and monitoring prior to and during the ED visit were compared by hyperkalemia severity (mild [> 5.0-5.5 mEq/L], moderate [> 5.5-6.0], severe [> 6.0]) using unadjusted analyses. Death, immediate inpatient admission, 30-day hyperkalemia recurrence, and 30-day inpatient admission were also assessed by severity. Results Of 6222 patients included, 4432 (71.2%) had mild hyperkalemia, 1085 (17.4%) had moderate, and 705 (11.3%) had severe hyperkalemia. Chronic kidney disease (39.9-50.1%) and heart failure (21.6-24.3%) were common. In the ED, electrocardiograms (mild, 56.5%; moderate, 69.6%; severe, 81.0%) and patients with at least two potassium laboratory values increased with severity (15.0%; 40.4%; 75.5%). Among patients with at least two potassium laboratory values, over half of patients (60.4%) had potassium levels <= 5.0 mEq/L prior to discharge. Use of potassium-binding treatments (sodium polystyrene sulfonate: mild = 4.1%; moderate = 17.1%; severe = 27.4%), temporizing agents (5.6%; 15.5%; 31.6%), or dialysis (0.4%; 0.8%; 3.0%) increased with severity; treatment at discharge was not common. Death (1.1%; 3.7%; 10.6%), immediate admission to inpatient care (5.8%; 8.7%; 12.7%), 30-day hyperkalemia recurrence (2.9%; 19.0%; 32.5%), 30-day inpatient admission with hyperkalemia (6.5%; 7.9%; 9.3%) also increased with severity. Conclusion Patients with moderate and severe hyperkalemia experienced elevated risk of hyperkalemia recurrence and hyperkalemia-related inpatient readmission following discharge from the ED from a descriptive analysis. Future research to assess strategies to reduce hyperkalemia recurrence and inpatient admission in this patient population would be beneficial.