Basal insulin therapy is associated with beneficial effects on postoperative infective complications, independently from circulating glucose levels in patients admitted for cardiac surgery

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The effect of insulin per se on infective complications during cardiac surgery was evaluated.

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Eight hundred twelve patients were included.

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Insulin therapy decreased infections independently from glycemic levels.

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Basal + premeal insulin therapy is well tolerated without severe hypoglycemia cases.

Background

Although hyperglycemia is a strong predictor of postoperative infective complications (PIC), little is known about the effect of basal insulin therapy (BIT) per se on PIC.

Aim

To evaluate if there is an association between BIT, independent of glucose levels, and a possible improvement of PIC during the perioperative cardiosurgery period (PCP).

Methods

In 812 patients admitted for cardiac intervention and treated with a continuous intravenous insulin infusion (CIII) for hyperglycemic levels (>130 mg/dl), a retrospective analysis was performed during the PCP (January 2009–December 2011). Upon transfer to the cardiac surgery division, if fasting glucose was ≥130 mg/dl, a basal + premeal insulin therapy was initiated (121 patients, group 1); for <130 mg/dl, a premeal insulin alone was initiated (691 patients, group 2).

Findings

Compared with group 2, group 1 showed reductions in PIC (2.48% vs 7.96%, p < 0.049; odds ratio: 0.294; 95% CI: 0.110–0.780), C-Reactive Protein (p < 0.05) and white blood cell (p < 0.05) levels despite glucose levels and CIII that were higher during the first two days after surgery (179.8 ± 25.3 vs 169.5 ± 10.6 mg/dl, p < 0.01; 0.046 ± 0.008 vs 0.037 ± 0.015 U/kg/h, p < 0.05, respectively). Normal glucose levels were achieved in both groups from day 3 before the discharge. The mean length of hospital duration was 18% lower in group 1 than in group 2 (7.21 ± 05.08 vs 8.76 ± 9.08 days, p < 0.007), providing a significant impact on public health costs.

Conclusions

Basal + preprandial insulin therapy was associated with a lower frequency of PIC than preprandial insulin therapy alone, suggesting a beneficial effect of basal insulin therapy on post-surgery outcome.