Relationship Between Elevated HbA1c and Deep Sternal Wound Infection in Patients Undergoing Cardiac Surgery

Abstract

Introduction: Hyperglycemia is common in patients with and without diabetes mellitus (DM) following cardiac surgery. Intra- and postoperative hyperglycemia has been shown to be an independent risk factor for deep sternal wound infection (DSWI) after cardiac surgery. However, whether the preoperative chronic glycemic control is associated with the risk of DSWI remains controversial. Hemoglobin A1c (HbA1c) provides a measure of glucose control over the prior 2-3 months. The aim of this study was to evaluate the relationship between preoperative HbA1c levels and DSWI in patients with DM undergoing coronary artery bypass grafting (CABG). Patients and Methods: Records of patients who underwent elective on-pump CABG were retrospectively reviewed. A total of 180 patients with DM were included in the study. Patients were excluded if their blood glucose levels were not adequately controlled in the perioperative period. A total of 200 consecutive patients without DM were taken as controls. Results: Median HbA1c levels were significantly higher in patients with DM [8.16 (7.2-10.4)] than in controls [5.49 (5-6)] (p< 0.001). There was no significant difference in DSWI incidence between patients with DM and controls [5% (n= 9) vs. 2% (n= 4); P= 0.1]. Hospital (p= 0.01) and intensive care unit stays (p= 0.005) were significantly longer in patients with DM. Conclusion: We found that DSWI was not associated with preoperative HbA1c levels in patients undergoing CABG. In addition, with adequate glycemic control in the perioperative period, our study demonstrated no significant difference with regard to DSWI between patients with DM and controls.