Global cerebral edema from hypercapnic respiratory acidosis and response to hyperosmolar therapy

Hypercapnic respiratory acidosis (HRA) causes cerebral vasodilation via perivascular extracellular pH changes.(1) Its ability to precipitate global cerebral edema (GCE) in the absence of acute brain injury is rare. Treatment in these reports involves mechanical ventilation.(2) We describe a rare case of HRA-induced GCE in a patient without brain injury and the efficacy of hyperosmolar treatment after mechanical ventilation failed.