Effects of enflurane anaesthesia and surgery on endocrine function in man.

Forty-five patients underwent enflurane anaesthesia and surgery. Anaesthesia alone evoked little change in the plasma concentrations of ACTH, cortisol or antidiuretic hormone (ADH), but there were significant increases during surgery. The plasma levels of aldosterone rose during anaesthesia alone, and a further increase was noted during surgery. Neither enflurane anaesthesia nor surgery significantly influenced plasma concentrations of renin activity and thyroxine. A significant decrease in the plasma triiodothyronine levels was detected during anaesthesia alone, and a further decrease was found during and following surgery. Enflurane anaesthesia did not affect the plasma level of luteinizing hormone (LH) in male subjects throughout surgery, but a significant decrease was detected in female patients on the first postoperative day. The plasma concentrations of testosterone decreased during anaesthesia alone and surgery, and a further decrease was noted on the first postoperative day.