Endocrine responses to head and neck surgery in men

It has been well established that surgical stress leads to profound changes in endocrine function and metabolism. However, the endocrine response varies depending upon the type and the extent of surgery. As no data were available about the endocrine changes during and following major head and neck surgery, this study was performed. Plasma levels of adrenocorticotropin (ACTH), cortisol, thyroid-stimulating hormone (TSH), thyroxin (T4), triiodothyronine (T3), growth hormone (GH), prolactin (PRL), gonadotropins (LH and FSH), oestradiol and testosterone were determined in 17 patients one day before, immediately after, as well as 2 and 4 days after head and neck surgery. An increase in ACTH, cortisol, PRL and GH, and a decrease in plasma oestradiol and testosterone values occurred immediately after surgery. There was a slow fall in cortisol levels after surgery, but they remained elevated even on the fourth postoperative day, whereas GH values returned on the fourth day to the initial level. There were no changes in gonadotropins, TSH and T3, but T4 values were found to be increased on the second and fourth postoperative day. The prolonged cortisol stimulation which was not described by other researchers after other kinds of surgery might be caused by vagal stimulation during and/or after head and neck surgery. Increased needs after a major head and neck surgery could explain the increment of T4 values.