Gynecologic Surgical Site Infections Are Associated With Postoperative Hyperglycemia

Background: Postoperative hyperglycemia has been associated with increased rates of infection following surgery. Though attention has focused on glycemic control following cardiac surgery, evidence suggests that the risk exists for other operations also. In preliminary work, we found that gynecologic (GYN) surgery was followed by hyperglycemia (blood glucose >140 mg/dl) in 50% of the patients, which is more than can be explained by diabetes alone. 

Objective: To determine if post-operative hyperglycemia is associated with surgical site infections following GYN surgeries. 

Methods: Case-referent study. Glucose was monitored immediately post operatively following GYN cases. Routine surveillance identified surgical space infections following GYN surgery. For each infected case, two referent cases were identified from the next and previous GYN cases. Laboratory records of glucose measures (finger stick and venous) were reviewed from the start until 24 hours after the operation. Maximum blood glucoses were compared between groups. 

Results: For 13 months of surveillance (7/2009-7/2010), there were 37 infections in 2,521 operations, for an overall rate of 1.5% (95% binomial confidence interval (CI) 1.0 to 2.0%). Data was not available for one case, and 3 of 36 infected and 9 of 72 referent cases did not have glucose measured following surgery (11%, 95% CI 6-22%). In the referent group, 50% had post-op glucoses above 140 mg/dl; in the group with infections, 73% had post-op hyperglycemia. The mean glucose was 143 (+/- 35) mg/dl in the referent group and 175 (+/- 48) mg/dl in the cases (P = 0.002 by Wicoxon Rank Sum).

Conclusions: Post-operative hyperglycemia is frequent and strongly associated with infection in GYN surgery.