Indicators of poor neurological prognosis in patients comatose due to intracranial bleeds and trauma: a systematic review and critical appraisal of the evidence

Purpose: To determine the neurological clinical signs predicting poor outcome in patients with coma from intracranial bleeds and closed head injury, using a systematic review of the literature. Data sources: A structured search of MEDLINE using search terms 'prognosis' and 'head injury', 'trauma' and 'intracranial bleed'. Study selection: Articles published since 1980 were selected if they studied an adult population, had a sample size greater than 50 patients, focused on bedside clinical signs and addressed long-term recovery and functional status. Data extraction: Relevant data were abstracted from all nine articles fulfilling inclusion criteria. Results: The overall coma recovery rate varied from 9% to 53% at one year for subarachnoid haemorrhage, from 41% to 60% for intracerebral bleeds, and from 47% to 77% for closed head injury. For all three aetiologies, bedside clinical signs were not helpful in predicting which patients had a poor outcome. An admission Glasgow coma score <5 was associated with a 5-11% chance of recovery. The lack of a pupillary light reflex on admission was associated with a 0-36% chance of recovery. Absent or abnormal doll's eye movements on admission translated into a recovery rate of 0-34%. Variation in the predictive strength of these clinical features may be due to design. Conclusions: Clinical signs are not consistently helpful in predicting poor outcome in patients with coma due to intracranial bleeds or trauma.