OBJECTIVE To describe the functional outcome of a select group of patients with severe head injuries who would a priori be assumed to have a dismal outcome and to determine prognostic factors that can be used for effective family counseling and rational utilization of scarce resources. METHODS Thirty-seven patients with severe head injuries (admission Glasgow Coma Scale (GCS) score < 8) with prolonged (> 96 hours) intracranial hypertension were studied. Parameters recorded included admission age, GCS, evidence of prehospital hypotension, initial computed tomography findings, intracranial pressure (ICP), cerebral perfusion pressure (CPP), and therapeutic intensity level. RESULTS Thirty-eight percent of patients in this study achieved a Glasgow Outcome Scale score (GOS) of 4 (moderate disability) or better when assessed 1 year after injury. Patients who achieved these good outcomes were significantly younger (mean 23.6 +/- 8.8 years) than patients who were severely disabled or worse (GOS 1-3) (34.3 +/- 15.0 years) (p = 0.0098). The mean admission GCS in the good-outcome group tended to be higher than that of the poor-outcome group (5.8 +/- 1.5 vs 4.8 +/- 1.6, p = 0.065). When patients with good outcomes (GOS 4 or 5) were compared with those with poor outcomes (GOS 1-3), no significant differences in mean or peak ICP, percentage of time intervals with elevated ICP, lowest recorded CPP, or length of ICP monitoring were detected. CONCLUSIONS Younger patients, particularly those with GCS > 5, have the potential for excellent recovery despite prolonged (> 96 hours) intracranial hypertension. These patients will benefit from continued aggressive ICP and CPP management.