Hyperkalemia in electrical burns: A retrospective study in Colombia

Classically, hyperkalemia has been regarded as a complication in patients with electrical burns. The etiology of hyperkalemia includes metabolic acidosis, destruction of red blood cells, rhabdomyolysis and the development of renal failure. The purpose of this study was to determine the prevalence of hyperkalemia within the first 24h after electrical burn injury and to evaluate the possible association of serum potassium concentration with cutaneous burn size (%TBSA) and serum creatine phosphokinase (CPK) concentration.

A retrospective, cross-sectional study was conducted, based on review of medical records of adult patients hospitalized in the first 24h post electrical injury. Serum potassium (K⁺) levels were divided into low, normal, and high groups, with breakpoints at 3.5mmol/L and 5.0mmol/L and normal 3.6-4.9mmol/L. To assess potential differences according to the time elapsed between the time of the injury and the sampling time, data were grouped as follows: t1: samples obtained in the first 6h post-injury; t2: samples taken at 6-12h; t3: samples taken at 12-24h.

336 patients were studied. The median age was 32 years old (IQR: 25-43). 95.2% of patients were men. Low and normal values of K⁺ were observed in 13.7% and 85.1%, respectively. The prevalence of hyperkalemia was only 1.2%, and was not related to previously-administered medications or to simple blood gas pH value during admission. CPK>10,000IU/L was observed in 22.6%. No association was found between the serum potassium concentration and either %TBSA burned or the highest CPK value.

First, patients admitted to our burn unit with electrical injury accompanied by significant skin and muscle injury rarely exhibit hyperkalemia. Secondly, the presence of hyperkalemia is independent of the severity of rhabdomyolysis or the extent of the burn.