[Treatment and factors associated with prognosis of hyperkalemia in the emergency department].

Objective: To survey treatment and prognosis of hyperkalemia patients in the emergency department and to analyze factors associated with all-cause in-hospital mortality.

Methods: We implemented electronic hospital information system, extracted demographic characteristics, underlying diseases, laboratory findings, potassium lowering therapy and prognosis of hyperkalemia patients [age ≥ 18 years, serum potassium (K) concentration ≥ 5.5 mmol/L] in the emergency department of Peking Union hospital in Beijing between June 1st 2019 to May 31st 2020. The enrolled subjects were divided into the non-survival group and the survival group according to their prognosis. Univariate analysis and Cox regression model were adopted to analyze factors affecting all-cause in-hospital mortality of hyperkalemia patients.

Results: A total of 579 patients [median age 64 (22) years; 310 men (53.5%) and 269 women (46.5%)] with hyperkalemia were enrolled, among which, 317 (54.7%), 143 (24.7%) and 119 (20.6%) were mild, moderate, and severe hyperkalemia, respectively. 499 (86.20%) patients received potassium-lowering therapy, forty-four treatment regimens were administered. Insulin and glucose (I+G, 61.3%), diuretics (Diu, 57.2%), sodium bicarbonate (SB, 41.9%) and calcium gluconate/chloride (CA, 44.4%) were commonly used for the treatment of hyperkalemiain the emergency department. The combination of insulin and glucose, calcium gluconate/chloride, diuretics and sodium bicarbonate (I+G+CA+Diu+SB) was the most favored combined treatment regimen of hyperkalemia in the emergency department. The higher serum potassium concentration, the higher proportion of administrating combined treatment regimen and/or hemodialysis (HD) (the proportion of administrating combined treatment regimen in mild, moderate, and severe hyperkalemia patients were 58.4%, 82.5% and 94.8%; the proportion of administrating HD in mild, moderate, and severe hyperkalemia patients were 9.7%, 13.3% and 16.0%, respectively). The proportion of achievement of normokalaemia elevated as the kinds of potassium lowering treatment included in the combined treatment regimen increased. The proportion of achievement of normokalaemia was 100% in the combined treatment regimen including 6 kinds of potassium lowering therapy. Among various potassium lowering treatments, HD contributed to the highest rate of achievement of normokalaemia (93.8%). 111 of 579 (19.20%) hyperkalemia patients died in hospital. Cox regression model revealed that complicated with cardiac dysfunction predicted higher mortality [hazard ratio (HR) = 1.757, 95% confidence interval (95%CI) was 1.155-2.672, P = 0.009]. Achievement of normokalaemia and administration of diuretics attributed to lower mortality (HR = 0.248, 95%CI was 0.155-0.398, P = 0.000; HR = 0.335, 95%CI was 0.211-0.531, P = 0.000, respectively).

Conclusions: Treatment of hyperkalemia in the emergency department were various. Complicated with cardiac dysfunction were associated with higher mortality. Achieving normokalaemia was associated with decreased mortality.