Effects of glycemia on immediate complications following CABG.

OBJECTIVE

We investigated the relationship between postoperative glucose levels (days 1 through 3) and immediate outcomes in patients who underwent isolated coronary artery bypass grafting (CABG).

METHODS

We conducted a retrospective study of 2,558 consecutive patients who had isolated CABG. Patients were stratified into 3 groups based on their pre-operative mortality risk (MR), using Society of Thoracic Surgeons' criteria. Average glucose levels for the first 3 days following surgery were determined. Glucose levels for each group were divided into quartiles and related to relevant outcomes. Odds ratios assessing changes in outcomes as functions of increased glucose exposure were determined for postoperative days 1, 2, and 3 and for postoperative days 1 and 2 and 1 through 3.

RESULTS

The number of patients in each MR group (1 through 3; low, medium, and high) was 1,233, 852, and 473, respectively. Mean ± SD quartile glucose levels for days 1 and 2 were 133 ± 8.2, 150.4 ± 4.7, 167.2 ± 6.89, and 205.9 ± 24.9 mg/dL. The proportion of patients with a glucose level <70 mg/dL was 6.4%, <60 mg/dL was 2.7%, and <50 mg/dL was 1.1%. The most consistent and significant correlations between glucose quartiles and outcomes were observed for MR group 1, and they were most significant for the first 2 days following surgery. Glycemic control was not correlated with mortality, but it was correlated with total complications.

CONCLUSION

Hyperglycemia during the first two days after CABG adversely affected total complications in patients who were in the low and medium MR groups, but it did not significantly affect hospital mortality.