Posttraumatic cerebral hemispheric swelling

Abstract
The authors have analyzed the clinical course and intracranial pressure (ICP) changes in 55 severely head-injured patients presenting with bulk enlargement of one cerebral hemisphere within a few hours after trauma. These patients represent 10.5% of a series of 520 patients with severe head injury studied with computerized tomography (CT). Cerebral hemispheric swelling has the highest mortality rate and the shortest survival period after trauma in all series of severe head injury. In this series, it was associated with an ipsilateral subdural hematoma of variable size in 47 patients (85%) or with a large epidural hematoma in five patients (9%); in three patients (5.4%) it occurred as an isolated lesion. Evacuation of an associated extracerebral hematoma, which was performed within 4 hours after injury in only 20% of cases, scarcely changed the patients' preoperative neurological status. The high incidence of arterial hypotension and/or hypoxemia at admission (47% of cases) and the severity of the clinical presentation (82% of patients scored 5 points or less on the Glasgow Coma Scale, 74% had unilateral or bilateral mydriasis, and 80% had an initial ICP above normal) correlated with a very poor final outcome (87% mortality). Only one of the 11 patients with normal initial ICP continued to have normal pressure throughout the course. High-dose thiopental failed to control severe intracranial hypertension in 24 patients (51%) who had a fulminant, malignant course. A transient decrease in ICP elevation was achieved in 15 patients (31.4%) and definitive control in eight patients (17%), among whom were the seven survivors in this series. In the authors' experience, once ICP is controlled, barbiturate administration should not be discontinued until a control CT scan shows complete disappearance of the mass effect.