The adrenocortical response to craniotomy for brain tumor

Abstract

✓ The diurnal plasma cortisol content was determined in 32 patients with supratentorial brain tumors preoperatively and over a period of 9 days postoperatively. Craniotomy caused an elevation of plasma cortisol at least 25% above that achieved after other types of surgery. This high level of circulating cortisol was maintained on the first postoperative day and then gradually descended to preoperative levels by the 9th postoperative day. The usual diurnal pattern was reversed in 15% of postoperative observations. While in the majority of instances this reversal accompanied a distinct aberration from the normal postoperative course, 40% of the time no abnormality in the postoperative course could be detected to account for this reversal. It is concluded that substitution corticosteroid therapy when needed by a patient undergoing craniotomy should be maintained at high levels for at least 5 days postoperatively and then decreased slowly to maintenance levels by the 8th to 10th postoperative day. The progressive decline in circulating plasma cortisol from the 1st to 5th postoperative days, the same period during which postoperative cerebral edema is developing to its maximum, suggests that cerebral edema of itself does not evoke an adrenocortical response.