Ｔｒａｕｍａｔｉｃ ａｓｐｈｙｘｉａによる心停止後に一過性の脳幹障害を伴ったα昏睡の１例

Abstract

We describe a patient with brainstem dysfunction who developed alpha coma after cardiac arrest due to traumatic asphyxia. A 22-year-old man was brought to our hospital in deep coma after being resuscitated. Neurological examination revealed no brainstem reflexes except breathing. The results of a CT scan of the brain were unremarkable. The initial EEG was flat, but BAEPs showed no abnormal findings. On hospital day 3 the patient was still comatose with tetraplegia and bilateral facial palsy, but the brainstem reflexes had returned. An EEG showed a 12Hz alpha rhythm of about 50μV with preponderance over the anterior regions. SEPs showed prolonged latency upon stimulation of left median nerve and left posterior tibial nerve. The blink reflexes showed a normal R1 latency, but a prolonged R2 latency, directly and indirectly. MRI of the brain showed no abnormal findings. Two weeks later, the patient assumed a decorticate posture. Serial CTs showed moderate cerebral atrophy, and serial EEGs showed that low-amplitude delta activity had supervened. One year later, the patient was able to wink and swallow, but still suffered tetraplegia. Residual SEP abnormalities had improved, however, the prolonged R2 latency remained unchanged. Serial neurological and electrophysiological findings suggested that alpha coma occurs not as a result of damage to the brainstem, but of extensive damage to the cerebrum.