Intraoperative hyperglycemia is independently associated with infectious complications after non-cardiac surgery

Amy M. Shanks, Derek T. Woodrum, Sathish S. Kumar, Darrell A. Campbell, Sachin Kheterpal

Perioperative hyperglycemia and its associated increase in morbidity and mortality have been well studied in the critical care and cardiac surgery literature. However, there is little data regarding the impact of intraoperative hyperglycemia on post-operative infectious complications in non-cardiac surgery. All National Surgery Quality Improvement Program patients undergoing general, vascular, and urological surgery at our tertiary care center were reviewed. After integrating intraoperative glucose measurements from our intraoperative electronic health record, we categorized patients as experiencing mild (8.3-11.0 mmol/L), moderate (11.1-16.6 mmol/L), and severe (≥ 16.7 mmol/L) intraoperative hyperglycemia. Using multiple logistic regression to adjust for patient comorbidities and surgical factors, we evaluated the association of hyperglycemia with the primary outcome of postoperative surgical site infection, pneumonia, urinary tract infection, or sepsis within 30 days. Of 13,954 patients reviewed, 3150 patients met inclusion criteria and had an intraoperative glucose measurement. 49% (n = 1531) of patients experienced hyperglycemia and 15% (n = 482) patients experienced an infectious complication. Patients with mild (adjusted odds ratio 1.30, 95% confidence interval [1.01 to 1.68], p-value = 0.04) and moderate hyperglycemia (adjusted odds ratio 1.57, 95% confidence interval [1.08-2.28], p-value = 0.02) had a statistically significant risk-adjusted increase in infectious complications. The model c-statistic was 0.72 [95% confidence interval 0.69-0.74]. This is one of the first studies to demonstrate an independent relationship between intraoperative hyperglycemia and postoperative infectious complications. Future studies are needed to evaluate a causal relationship and impact of treatment.