Endocrine and metabolic responses after standardized moderate surgical trauma: influence of age and sex.

The endocrine and metabolic responses to elective cholecystectomy and the influence of age and sex on this stress response were investigated in 21 patients, eight men and 13 women. The patients were divided into two groups, older (n=10) and younger (n=11) than 55 years respectively. Arterial plasma concentrations of catecholamines, cortisol and free fatty acids as well as serum insulin and arterial blood concentrations of glucose, lactate, glycerol, alanine and 3-hydroxybutyrate were measured preoperatively and 2, 24, 48, 72 and 96 h after the start of surgery. Oxygen uptake and CO2 production were measured and respiratory quotient (RQ) was calculated. All hormones and metabolites except insulin and alanine were significantly elevated immediately after surgery. At 24 h plasma noradrenaline and blood glucose were still significantly increased. Serum insulin was increased at 24 and 48 h. Oxygen uptake and plasma cortisol were significantly elevated throughout the period studied and blood alanine was decreased from 2 to 72 h after surgery. The older group showed a significantly higher increase in noradrenaline and lactate, whereas women preoperatively as well as postoperatively had higher glycerol levels. At the end of the period studied women had higher FFA-levels. We conclude that cholecystectomy evokes a significant endocrine and metabolic response and that some of the variables studied are still significantly altered up to 4 days postoperatively. The influence of age and sex on this stress response is of minor importance.