Prolactin response to severity of surgical insult

ABSTRACT

We previously showed that prolactin levels are significantly elevated during the recovery process from surgical insult, implying a role for prolactin in the neuroendocrine immune network. Our present study investigates the importance of severity of surgical insult to the prolactin response. Two groups of surgical patients were studied 7 patients scheduled for "clean" elective surgery, herniorrhaphy and laparoscopic cholecystectomy, were compared to 7 patients scheduled for prolonged abdominal exploration. Patients who were pregnant or immediate postpartum or on medications affecting prolactin levels were not studied. Blood was drawn for prolactin and cortisol at 800 a.m. on the day of surgery prior to the procedure and on postoperative days 1,3 & 5. Prolactin was measured by a chemiluminescence assay (CIBA Corning, NY). Cortisol was measured by radioimmunoassay (INCSTAR). An advanced analysis software SPSS for Windows 6.0 was used to analyze the collected data. The "clean" surgery group consisted of 4 females and 3 males, mean age 51.5 years. The "prolonged" surgery group consisted of 5 males and 2 females, mean age 61.0 years. Using the two tailed test prolactin levels on post operative days 3 & 5 showed statistically significant increased compared to pre-operative levels in the prolonged surgery group. The "clean" surgery group showed no statistically significant changes in prolactin concentration. Cortisol levels were not significantly elevated in either group. The prolactin response to surgery is related to the severity of surgical insult. We postulate that the prolactin response correlates with the magnitude of the immune response.(AU)