Evaluation and Management of Pituitary-Adrenal Function After Pituitary Surgery

Abstract

Selective adenomectomy is the preferred treatment option for most pituitary adenomas, other than prolactinomas. Its safety and efficacy in the management of secreting or nonsecreting micro- or macroadenomas are well established. Pre- and postoperative endocrine management include, among other things, evaluation of pituitary function with particular attention to the hypothalamic-pituitary-adrenal axis (HPA-A). Published data involving a large number of patients demonstrate that when the HPA-A is normal preoperatively, corticosteroids are not necessary before, during, or after surgery. However, patients should be monitored postoperatively to document adequate adrenal function. In contrast, patients with preoperative impairment of HPA-A function as well as those with pituitary tumor apoplexy are given glucocorticoids before, during, and immediately after surgery. Thereafter, corticosteroids can be discontinued abruptly and patients monitored for possible recovery of HPA-A. The latter is conveniently done by measuring serum cortisol levels twice daily. Alternatively, glucocorticoids can be continued for several weeks when HPA-A can be assessed in detail. We prefer the former option because it provides rapid assessment of HPA-A without jeopardizing the patient's well being. Patients with ACTH-secreting pituitary adenomas are not given steroid during or after surgery. Instead, they are closely monitored after adenomectomy for clinical and/or biochemical evidence of adrenal insufficiency. Once the latter is documented, glucocorticoid replacement therapy is initiated and continued until HPA-A returns to normal. The latter approach provides rapid assessment of the completeness of adenomectomy without jeopardizing patient care.