Effects of surgery and general or epidural anesthesia on plasma levels of Cortisol, growth hormone and prolactin in infants under one year of age

Abstract

Twenty infants under one yr of age undergoing minor surgery were divided in two groups according to the type of anesthesia (epidural, Group 1, n = 10; general, Group 2, n = 10) which was randomly performed. Blood samples for Cortisol (F), growth hormone (GH), and prolactin (PRL) determination were taken from each infant in baseline conditions, before surgery, and at the end of surgery. Mean plasma F levels in infants of group 2 rose significantly (p < 0.01) before surgery to attend a maximum at the end of surgery (p< 0.005). In infants of Group 1 a significant increase was also observed before surgery (p < 0.05) but at the end of surgery mean plasma cortisol returned to levels comparable to baseline. Mean GH plasma levels were not significantly affected by both types of anesthesia, however an increase (not statistically significant) was observed at the end of surgery in both groups. Mean plasma PRL levels showed a significant increase before surgery (p < 0.05 and p < 0.01 in group 1 and 2, respectively) and a further increase at the end of surgery in both groups of infants (p< 0.005). These results suggest that in infants under one yr of age both types of anesthetic procedures preceding surgery have no significant effect on plasma GH, but produce a significant increase of cortisol and prolactin mean plasma levels. The cortisol response to surgery and general or epidural anesthesia was similar to that reported in adults and prepubertal boys. At difference with adult subjects the PRL response to surgery and general anesthesia was not prevented by epidural anesthesia and the GH increase observed after surgery and general anesthesia was not statistically significant.