Perioperative serum cortisol levels in ACTH sufficient and ACTH deficient patients during transsphenoidal surgery of pituitary adenoma

Abstract

Purpose: No previous study has analyzed serum cortisol levels during transsphenoidal endoscopic pituitary surgery in patients with and without hydrocortisone (HC) substitution.

Methods: A total of 15 patients undergoing surgery for a pituitary adenoma were studied. Those with normal ACTH function were either not given HC (n = 7) or received 50 mg intravenous HC at the start of surgery (n = 4). Patients with ACTH deficiency received intravenous HC of 100 mg in the morning before surgery (n = 4) with the additional 50 mg for an afternoon operation (n = 2). Propofol and remifentanil were used as anesthetics. Serum cortisol was measured at the start of and every 30 min during surgery.

Results: Among 7 patients with normal ACTH function without HC substitution, cortisol levels before surgery were 126-244 nmol/L, among the 4 patients undergoing surgery in the morning, whereas the 3 who underwent surgery in the afternoon had lower levels, 38-76 nmol/L. During nose/sinus surgery cortisol levels decreased to 79-139 and 24-54 nmol/L, respectively. At intrasellar manipulation a distinct rise was noted. Also, in the 4 ACTH sufficient patients receiving HC, cortisol levels decreased during nose/sinus surgery, but only with a slight increase during intrasellar surgery. In the 4 ACTH deficient patients cortisol peaked at 1914-2582 nmol/L.

Conclusions: Patients with normal ACTH function without HC substitution had very low cortisol levels during the first part of surgery, likely suppressed by the anesthetics. After mechanical impact in the sella, a marked increase in cortisol was noted. Supraphysiological cortisol levels were achieved with our routine HC substitution, advising us to reduce the supplementation.

Keywords: Hydrocortisone; adrenal insufficiency; pituitary gland; adrenocorticotropic hormone; endoscopic transsphenoidal surgery; remifentanil.

Fig. 1

Doses of propofol (mL) and remifentanil (mL) in the patients without HC (n = 7), with 50 mg (n = 4), 100 mg (n = 2), and 100 + 50 mg (n = 2) HC, respectively

Fig. 2

Serum cortisol levels in ACTH sufficient patients who did not receive any hydrocortisone substitution during pituitary surgery performed in the a morning (n = 4) and b afternoon (n = 3). Serum cortisol was measured from the start to the end of surgery. White arrows (⇩) indicate the first sample obtained after intrasellar manipulation (60–150 min)

Fig. 3

Serum cortisol levels in patients with perioperative hydrocortisone substitution, ACTH sufficient (n = 4) and ACTH deficient (n = 4), during pituitary surgery in the a morning (n = 6) and b afternoon (n = 2). Serum cortisol was measured from the start to the end of surgery. ACTH sufficient patients received 50 mg HC about 1 h before start of surgery. ACTH deficient patients received 100 mg at 6 AM, and those with surgery in the afternoon also received additional 50 mg during surgery, 8 h after the morning dose. Black arrows (⬇) indicate the first sample obtained after the 50 mg dose (b). White arrows (⇩) indicate the first sample obtained after intrasellar manipulation