Auditory brainstem response: prognostic value in patients with a score of 3 on the Glasgow Coma Scale.

OBJECTIVE: To evaluate the prognostic value of auditory brainstem response (ABR) recorded in comatose patients presenting a score of 3 on the Glasgow Coma Scale (GCS = 3).

PATIENTS: One hundred thirty-eight patients in coma at GCS = 3 due to various etiologic agents.

INTERVENTION: To record and analyze tracings of ABR.

MAIN OUTCOME MEASURE: Tracings from ABR were classified into four types (B1, B2, B3, and B4) on the basis of synchrony of waves.

RESULTS: The Fischer's exact test used for comparison between death proportions revealed that B1 is different from B2, B3, or B4 and the association B2 + B3 + B4.

CONCLUSION: Auditory brainstem response is a useful tool with prognostic value for patients in coma with GCS = 3. It was demonstrated in our series that once the patient presented an abnormal ABR (B2, B3, or B4), he had a greater probability of dying than a patient with a normal ABR (B1).