Hormonal response to surgical stress in schoolchildren

To determine hormone concentrations (ACTH, cortisol, beta-endorphin) in children before and after surgery, to assess the correlation between any hormonal changes and to study the influence exercised on them by the severity of surgical stress and the elective/emergency nature of the surgery.

Prospective cohort of 78 children (age= 10+/-2.6 years, range 6-13 years) undergoing elective or emergency surgery. Preoperative and postoperative (1 and 24 hours postoperation) plasma concentrations of ACTH, cortisol and beta-endorphin were determined in all children. The severity of surgical stress was evaluated as low (< 6) or high (> 6) according to the Oxford scale. Student's t-test was used to analyse hormonal changes and the influence of degree of surgical stress and elective/emergency character of the surgery, and Pearson's coefficient for correlations between hormonal values. p < 0.05 was regarded as significant.

We observed a significant increase in hormonal concentrations one hour after surgery. ACTH and cortisol values normalised 24 hours after surgery, but beta-endorphin concentrations remained increased. There was a correlation between ACTH and beta-endorphin values both before surgery and one hour after. Operations with high surgical stress significantly increased cortisol concentrations one hour after surgery and beta-endorphin concentrations 24 hours after surgery. Patients selected for emergency surgery showed significantly higher concentrations of cortisol and ACTH both before and after surgery.

Postoperative hormonal response among children of school age is characterised by increases in ACTH, cortisol and beta-endorphin one hour after surgery, and by high concentrations of beta-endorphin 24 hours after surgery. Cortisol is an index of surgical stress. Emergency surgery is associated with significant increases in ACTH and cortisol.