Influence of superior cervical sympathectomy on traumatically induced brain oedema.

Abstract

Traumatic brain oedema was induced in rabbits by trephine craniotomy which causes circumscribed thermal injury to underlying structures. The amount of oedema was estimated as the per cent water content in brain as determined after heat combustion. The water content was thus measured in the brain of non‐sympathectomized animals and after bilateral superior cervical sympathectomy, with or without additional trephine traumatization. Changes in brain water simply reflecting altered cerebral blood volume after sympathectomy could be corrected for. Sympathectomy 32 hours before water determination caused about 50 per cent reduction in the amount of traumatic brain oedema. At 5 days the degree of oedema was of the same magnitude as in the non‐sympathectomized animals subjected only to trephination. Fifteen days after sympathectomy the amount extended 50 per cent above that in the trephinized, non‐sympathectomized animals. It is suggested that the cranial sympathetics can modify the extent of a traumatic brain oedema through its action on the cerebrovascular system.