Low potassium dialysate is associated with decreased mortality in patients with end-stage kidney disease admitted to the hospital with severe hyperkalemia, investigators report.
A total of 209 patients on hemodialysis were admitted to the hospital with a serum potassium level higher than 6.5 mmol/dL (mean 7.1 mmol/L). A median 2 hours later, 47.4% of patients underwent dialysis with a 1 mEq/L concentration potassium bath, whereas the remaining patients received baths with higher potassium concentration only. Overall, 13 patients (6%) died and 15 (7.5%) experienced cardiac arrest during the hospitalization.
Use of a 1 mEq/L potassium bath during some portion of the dialysis session was associated with significant 73% lower odds of mortality or cardiac arrest compared with use of only higher potassium baths, after adjusting for age, sex, race, history of diabetes mellitus, hypertension, serum potassium levels, and time to dialysis, Tripti Singh, MD, of the University of Wisconsin School of Medicine and Public Health in Madison, Wisconsin, and colleagues reported in Clinical Kidney Journal. Most patients received the 1 mEq/L potassium bath during the first hour of dialysis, then transitioned to higher potassium baths.
“The use of 1K bath is associated with increased removal of total potassium during the dialysis session, thus much more likely to achieve a lower post treatment serum potassium,” the investigators explained.
This finding differs strikingly from outpatient dialysis, where prolonged use of 1 mEq/L potassium dialysis bath correlates with increased mortality. In the hospital, a 1K bath is used for only 1 to 2 dialysis sessions, the researchers explained. Potassium levels are checked frequently and allow for potassium replacement in case of overcorrection. Inpatients’ cardiac rhythm and hemodynamics are also monitored more closely.
Studies on outpatient practices should not guide inpatient hyperkalemia treatment, according to Dr Singh’s team.
Singh T, Alagasundaramoorthy S, Gregory A, Astor BC, Maursetter L. Low dialysis potassium bath is associated with lower mortality in end stage renal disease patients admitted to hospital with severe hyperkalemia. Clin Kidney J. doi:10.1093/ckj/sfaa263/6040744