Pituitary-adrenocortical response after craniotomy for brain tumor, and its suppression with administered glucocorticoid.

Nowadays large doses of glucocorticoids are administered to prever.t cerebral edema during and after craniotomy for brain tumor. The influence of this glucocorticoids therapy on the hypothalamo-pituitary-adrenocortical response was studied clinically. Urinary total 17-hydroxycorticoids excretion ( 17-0H-CH) was estimated. Preoperative basal level of 17-0H-CS in brain tumor cases was lower than normal basal level except in some cases in which rapid increase in intracranial hypertension was the main sign. Adrenocortical response was more intense in brain tumor craniotomy than in other operations such as lumbar sympathectomy for Buerger's disease or craniotomy for various diseases of the brain and skull other than brain tumor. Large doses of dexamethasone administered prophylactically to prevent cerebral edema, suppressed significantly this intense response to brain tumor craniotomy. It was reduced to a degree equal to :;tdrenocortical response to operations of control cases. In most cases suppression with dexamethasone in craniotomy was correlated to preoperative suppression test with dexamethasone, suggesting that the same mechanism might play in both resting and stressful conditions. More than four weeks after the operation, influence of this prophylactic dexamethasone therapy was t ested; the suppression test was made and found to be within normal limit. Glucocorticoids therapy to prevent cerebral edema is supported from this point of view, for the adrenocortical reserve may be maintained even during and after craniotomy.