Background: Patients with diabetes have a higher risk of complications following coronary artery graft surgery (CAGS)¹. Best practice guidelines stipulate maintaining post-operative blood glucose (BG) < 10mmol/L¹. Recommendations for transition from intravenous insulin infusion include initiation of long acting subcutaneous insulin prior to its cessation².

Aim: To review glycaemic management of CAGS patients for 24 hours before and 72 hours after cessation of a post-operative intravenous insulin infusion.

Methods: CAGS patients with diabetes who were operated on from September 2013 to August 2014 (n = 76) were identified by medical record coding at a tertiary referral hospital. Demographic and blood glucose outcome data were collected from patients who received an intravenous insulin infusion post-operatively. Results were used to inform development of an insulin infusion transition guideline, which was implemented in July 2015. A post implementation audit was conducted in March 2016.

Results: Prior to implementation of the guideline, 85% (n = 57/67 available records) of patients with diabetes received an intravenous insulin infusion following CAGS. Of these, 23% (n = 13/57) were administered long-acting insulin subcutaneously before ceasing the insulin infusion and 74% (n = 42/57) were prescribed ongoing supplemental insulin.  Mean BG was 9.3 ± 1.1 mmol/L in the 24 hours prior to ceasing the infusion and 10.9 ± 2.3, 11.3 ± 2.9 and 10.0 ± 2.7 mmol/L 24, 48 and 72 hours respectively after ceasing the infusion. In 58 patients studied following implementation of the guideline, mean BG was 9.1 ± 1.0 mmol/L (-0.2 mmol/L, P=0.22) in the 24 hours prior to ceasing the infusion and 10.2 ± 2.3 (-0.7 mmol/L, P=0.14), 10.0 ± 2.6 (-1.1 mmol/L, P=0.013) and 8.1 ± 2.4 mmol/L (-1.9 mmol/L, P<0.001) 24, 48 and 72 hours respectively after ceasing the infusion. 

Conclusion: Development and implementation of an insulin infusion transition guideline improved post-operative glycaemic outcomes.