Reduction in cortisol inactivation is part of the adrenal stress response to cardiac and noncardiac pediatric surgery: a prospective study using gas chromatography-mass spectrometry analysis.

We examined the hypothesis that major cardiac surgery triggers a more intense adrenal stress response than less intensive noncardiac surgery, which then alters cortisol inactivation. Urinary excretion rates of glucocorticoid metabolites were determined before and after surgery using gas chromatography-mass spectrometry in 29 children undergoing scheduled major cardiac surgery and 17 control children undergoing conventional noncardiac surgery in a prospective observational study. Excretion rates of glucocorticoid metabolites were summed and corrected for creatinine excretion to calculate cortisol production rates (mg/mmol creatinine/m(2) body surface area). Precursor/product ratios from individual metabolites were calculated to characterize cortisol inactivation (11ß-hydroxysteroid dehydrogenase). Postoperatively, median cortisol production rates increased in both groups ( MCS: from 2.7 to 9.3; controls: from 2.7 to 5.8; p<0.001) with no significant difference between groups (p=0.12). Ratios of cortisol to cortisone metabolites, indicating the overall activity of 11ß-hydroxysteroid dehydrogenase, increased postoperatively in both groups (p<0.001). In conclusion, surgery resulted in a distinct postoperative increase in cortisol production. In contrast to our hypothesis, children undergoing major cardiac surgery did not show an increased adrenal stress response compared to children undergoing conventional surgery. Furthermore, the reduction in cortisol inactivation appears to be an essential part of the stress response to pediatric surgery in general.

Influence of cholesterol and fat in food on indirect parameters of exocrine pancreatic function.

Fecal elastase 1, chymotrypsin activity, and fat content in stool are clinical parameters of exocrine pancreatic function. The aim of this study was to clarify the possible impact of extreme changes in diet on fecal enzyme concentration/activity, since extreme diets may lead to wrong conclusions in the diagnosis of pancreatic insufficiency. Twelve healthy test persons followed 4 diet phases, each with a duration of 6 days. The 4 diet phases were (1) nearly fat-free with a low-cholesterol content; (2) high in fat and low in cholesterol; (3) high in cholesterol deriving from meat, and (4) high in cholesterol deriving from eggs. At the end of each diet phase, a 72-hour stool collection was carried out to measure fecal elastase 1, chymotrypsin and fecal fat content. The results showed no significant changes after each of the 4 diet phases. The clinical parameters of fecal elastase 1 and chymotrypsin activity in stool do not seem to be significantly influenced by fat and cholesterol deriving from food.