Effect of Anesthesia on Insulin Secretion in Patients With Preoperative Decreased Insulin Sensitivity

Effect of Anesthesia on Insulin Secretion in Patients With Preoperative Decreased Insulin Sensitivity

Effect of Epidural Anesthesia and Analgesia on Insulin Secretion in Patients With Preoperative Decreased Insulin Sensitivity

Epidural anesthesia has been found to manipulate the hyperglycemic response to surgery. It is unclear, however, whether the preoperative metabolic status of the surgical patient plays a role in the degree of this hyperglycemic response. For instance, the presence of low insulin sensitivity before surgery could predispose the individual to an altered metabolic response after surgery. In this case, it would be appropriate to identify adequate interventions that attenuate the response to surgical stress and facilitate the recovery process. The aims of this research projects are the following: To determine the extent in which epidural local anesthetics, initiated before surgery and continued after surgery, improves insulin secretion in patients with preoperative low insulin sensitivity. To understand which measures of postoperative recovery are sensitive to the restoration of insulin secretion in this particular group of patients

Patients will receive general anesthesia alone followed by intravenous morphine for postoperative pain control. This techniques is safe and is standard procedure for colorectal surgery.

Patients will receive general anesthesia plus epidural anesthesia followed by epidural analgesia for postoperative pain control. This techniques is safe and standard procedure for colorectal surgery.

Patients will be randomized to receive either epidural or general anesthesia for pain management throughout their surgery.

The Hyperinsulinemic-euglycemic clamp is the gold standard for measuring insulin sensitivity. Patients receive a 2 hour infusion of glucose and insulin, which is adjusted throughout the study period in order to maintain a blood glucose concentration at 5.5mmol/L. The test will take place one week before surgery and on the second postoperative day.

Inclusion Criteria: Patients receiving elective resection of malignant, non metastatic, colorectal lesions Exclusion Criteria: American Society of Anesthesiologists (ASA) health status class 4-5 Dementia,neuromuscular disease, psychosis Cardiac abnormalities Severe end-organ disease such as cardiac failure (New York Heart Association classes I-IV) Chronic obstructive pulmonary disease Renal failure (creatinine > 1.5 mg/dl) Hepatic failure (liver transaminases >50% over the normal range) Diabetics with glycosylated hemoglobin > 6% Steroid consumption longer than 30 days sepsis Morbid obesity (body mass index >40) Anemia (hematocrit < 30 %, haemoglobin <10g/dl, albumin < 25mg/dl). Patients will be excluded if they have poor English or French comprehension.

Donatelli F, Corbella D, Di Nicola M, Carli F, Lorini L, Fumagalli R, Biolo G. Preoperative insulin resistance and the impact of feeding on postoperative protein balance: a stable isotope study. J Clin Endocrinol Metab. 2011 Nov;96(11):E1789-97. doi: 10.1210/jc.2011-0549. Epub 2011 Aug 31.