Clinical recovery of consciousness after traumatic coma.

OBJECTIVE

To describe early clinical stages in the recovery of consciousness, using selected items from the Glasgow Coma Scale and the Liège Coma Scale.

DESIGN

Validation cohort study, conducted in a tertiary care center.

SETTING

Neurosurgical intensive therapy unit in a university teaching hospital.

PATIENTS

Patients (n = 137) with traumatic coma who were selected according to the following criteria: a) coma due to blunt head trauma with an initial Glasgow Coma Score of < or = 7; b) admission to the neurosurgical intensive therapy unit within the first 24 hrs after trauma; c) patients > 14 yrs of age; requiring endotracheal intubation, mechanical ventilation, and the administration of drugs; and d) survival period allowing analysis of the recovery of consciousness.

MEASUREMENTS AND MAIN RESULTS

Arousal, as expressed by stimulated opening of the eyes and recorded as a delay in days, was correlated with the appearance of the localized pain response, capacity to obey commands, blink reflex, and the cessation of drugs in three groups of patients. These groups were defined according to the time in which there was an appearance of the stimulated opening of the eyes: < 8 days (group 1); between 8 and 15 days (group 2); and after 15 days (group 3). When the three groups of patients were compared, significant differences existed between the mean delays of appearance of stimulated eye opening and the appearance of the blink reflex. Extubation coincided with the appearance of spontaneous eye opening, with a mean delay of 13.5 days.

CONCLUSIONS

This study confirms the classical clinical sequence of arousal and recovery of consciousness, with the appearance of stimulated eye opening and the blink reflex first, followed by spontaneous eye opening, and the capacity to obey commands in intubated, traumatized, coma patients. A direct correlation existed between the delay of arousal and the complete recovery of consciousness. When groups of patients with various mean delays for the appearance of stimulated eye opening are considered, reappearance of the blink reflex did not always coincide with stimulated eye opening, suggesting differing structural and functional brain recovery processes.