Insulin Resistance, Glycemia and Cortisol Levels in Surgical Patients who Had Preoperative Caloric Load with Amino Acids

Introduction: Surgical stress response, results in elevated levels of anti-insulin hormones and reduced insulin secretion. This hormonal state may be detrimental for surgical patients due to the presence of insulin resistance and hyperglycemia. Additionally, pre-operative fasting favors this conditions. The aim of this study is to analyze the impact of pre-operative caloric load, with 440kJ from amino acid infusions on the levels of glucose, cortisol and insulin resistance in surgical patients.

Material and Methods: The study included 20 female patients scheduled for mastectomy, aged 30-60 years without diabetes and BMI < 30 m², divided into two groups. The study group A, the evening before the surgery, received 1000 ml amino acid infusions, while the control group B didn′t receive any infusion. In both groups glucose, C-peptide and cortisol levels were determinate preoperatively and postoperatively. From the obtained C-peptide and glucose values, with the help of computer model (HOMA2*), the insulin resistance (IR), functionality of beta cells (BETA) and insulin sensitivity (IS) were calculated.

Results: Postoperative values of insulin resistance (0.94 ± 0.12 vs 1.13 ± 0.2; p = 0.02) and glucose (4.79 ± 0.5 vs 5.77 ± 0.6; p = 0.002) were lower in the study group compared to control group. Postoperative cortisol levels in both groups were higher than the preoperative, but no significant difference was found. The study group showed higher values for BETA and IS. Percentage changes between the groups were significant for all parameters.

Conclusion: Pre-operative caloric load (amino acids) reduces the level of insulin resistance and glucose in the presence of elevated cortisol levels.