Assessment of adrenal reserve and secretion of cortisol in patients over 60 years of age undergoing cardiac surgery

Introduction
Cortisol level affects the prognosis of patients after cardiac surgery. Meanwhile, there are no clear guidelines for steroid supplementation after a cardiac operation. The relationship between age and blood cortisol levels has not been finally clarified.

Aim
Assessment of adrenal reserve and secretion of cortisol in patients over 60 years of age undergoing cardiac surgery.

Material and methods
The study included 20 patients of both sexes referred for cardiac surgery. A short ACTH synthetic stimulation test was carried out. Assessment of cortisol secretion was carried out in the morning on the day of surgery and the 1st, 2nd and 4th days after surgery in blood samples.

Results
A result within the normal range for the adrenal reserve was found in 19 of the 20 patients enrolled in the study. The short Synacthen test predicted postoperative secretion of cortisol (p = 0.04, r = 0.047). A relationship between secretion of cortisol and patients’ age was observed (p = 0.03, r = 0.48). The concentration of cortisol on the 1st postoperative day was correlated with the total dose of dopamine (p = 0.006, r = 0.58) and adrenaline (p = 0.04, r = 0.47). The concentration of cortisol on the day of the surgery correlated with the lactate concentration on day 2 (p = 0.04, r = 0.45). The concentration of lactates on day 1 correlated with total dose of dopamine (p = 0.01, r = 0.54).

Conclusions
A short Synacthen test allows one to predict secretion of cortisol after cardiac surgery. Greater secretion of cortisol after cardiac surgery may be associated with a more difficult postoperative course. There was no decrease in cortisol secretion with age.