Perioperative hyperglycemia is common in cardiac surgery and is associated with adverse outcomes; however, optimal intraoperative glucose targets remain incompletely defined. We evaluated the association between intraoperative glycemic control and postoperative outcomes and assessed the impact of a prospectively implemented statewide quality improvement (QI) initiative.

Patients undergoing cardiac surgery with cardiopulmonary bypass from 2020 to 2024 within a statewide collaborative were retrospectively stratified by peak intraoperative glucose level (<180 mg/dL versus ≥180 mg/dL) for analysis. Primary outcomes included infectious complications, acute kidney injury (AKI), renal failure, stroke, and composite morbidity. Multivariable mixed-effects logistic regression models adjusted for patient, operative, and institutional factors. Interrupted time series analysis evaluated changes in glycemic control following QI implementation.

Among 22,747 patients, 74.2% achieved peak intraoperative glucose <180 mg/dL. Patients with peak glucose <180 mg/dL had lower rates of composite infection (4.75% vs 7.64%), AKI (23.46% vs 28.85%), and operative mortality (1.73% vs 3.31%) (all p<0.001). After adjustment, peak glucose <180 mg/dL remained associated with lower odds of surgical site infection (OR 0.81), sepsis (OR 0.61), pneumonia (OR 0.80), AKI (OR 0.86), renal failure (OR 0.79), and composite complications (OR 0.86); stroke was not associated. Following QI implementation, achievement of peak glucose <180 mg/dL increased from 66.9% to 88.2%, with a significant improvement in temporal trends (p<0.001).

Peak intraoperative glucose <180 mg/dL was independently associated with improved infectious and renal postoperative outcomes after cardiac surgery. A statewide QI initiative significantly improved glycemic control, supporting adoption of standardized intraoperative glucose management protocols.