Factors Associated with Increases in Glucose Levels in the Perioperative Period in Non-Diabetic Patients

Background: Blood glucose levels are elevated during the perioperative period as a result of the neuro-endocrine response to the stress of surgery. In nondiabetic patients, blood glucose levels are not a part of routine preoperative testing nor are they monitored during surgery or in the post anesthesia care unit (PACU). We measured blood glucose levels in nondiabetic patients during the perioperative period to identify how many patients had high glucose levels and what factors were associated with increases in blood glucose levels. Methods: This prospective observational study included two hundred and ninety five nondiabetic patients between the ages of 18 and 80 years, undergoing elective noncardiac surgery. Blood glucose levels were measured preoperatively and at frequent, predetermined intervals during surgery and in the PACU. Patient characteristics, surgical and anesthetic factors, and pain scores in the PACU were recorded, as were postoperative complications. Results: Forty nine percent (49%) of the patients had maximum intraoperative glucose levels of 126 mg/dl or higher and fifty three percent (53%) had maximum postoperative glucose levels of 126 mg/dl or higher. Preoperative glucose levels, family history of diabetes and amount of blood loss were statistically significantly associated with both max-intra-op and max-post-op glucose levels. Additionally, blood administration, surgery duration and race were significantly associated with max-intra-op glucose levels, while amount of intravenous fluids and sex were significantly associated with max-post-op glucose levels. Conclusion: A large number of nondiabetic patients in our study had maximum glucose levels >126 mg/dl in the perioperative period. Certain patient characteristics, as well as surgical/anesthetic factors, were associated with increases in the glucose levels. More studies are indicated to determine which patients may benefit from glucose monitoring in the perioperative period.