Although tight glucose control might reduce inflammation after cardiac surgery, it remains unclear whether inflammation can be controlled by maintaining glucose levels within 110-180 mg/dL. We hypothesized that a glucose target range of 110-180 mg/dL decreases inflammation after cardiovascular surgery. This retrospective study included 72 cardiovascular surgery patients divided into two groups according to the glucose control approach. Patients allocated to the closed-loop group received closed-loop glucose control (target glucose levels at 110-180 mg/dL) from admission to the intensive care unit until 9 a.m. on postoperative day (POD) 1. Patients allocated to the conventional group received conventional glucose control using a sliding scale method to maintain blood glucose levels < 200 mg/dL. Primary outcomes were C-reactive protein (CRP) levels on PODs 1, 2, and 7. Data were reported as mean ± standard deviation. Comparisons were performed using the chi-squared test and unpaired t test, with p < 0.05 indicating statistical significance. The closed-loop group had significantly lower average glucose levels (169 ± 24 vs. 201 ± 36 mg/dL, p < 0.001) and standard deviation of glucose levels (22 ± 13 vs. 44 ± 20 mg/dL; p < 0.001). The CRP levels on PODs 2 and 7 were significantly lower in the closed-loop group than in the conventional group (10.8 ± 5.6 vs. 14.1 ± 5.7 mg/dL, p = 0.02; 4.6 ± 2.5 vs. 7.3 ± 4.0 mg/dL, p < 0.001; respectively). Our findings suggest that glucose control using a closed-loop device might decrease inflammation after cardiovascular surgery without increasing hypoglycemia risk.
Keywords: Artificial pancreas; Cardiac surgery; Glucose control; Glucose variability; Inflammatory response.