In a burn injury, which laboratory result should the nurse expect?

• A. Metabolic alkalosis
• B. Hypervolemia
• C. Hyperkalemia
• D. Low hemoglobin

Answer: (C)

When tissue is damaged in a burn, cells break apart and their contents spill into the extracellular space. Potassium is one of those intracellular contents, so serum potassium rises in the acute phase. This makes hyperkalemia the lab finding you’d expect after a burn.

Metabolic alkalosis is unlikely because burn injury and the resulting hypoperfusion typically cause metabolic acidosis, not alkalosis. Hypervolemia doesn’t fit because burns cause extensive fluid loss from the vascular space, leading to hypovolemia rather than an excess of fluid. Low hemoglobin isn’t expected in the immediate phase either; fluid shifts often concentrate red cells, potentially increasing hemoglobin/hematocrit rather than decreasing them.