Comparison of glycemic and surgical outcomes after change in glycemic targets in cardiac surgery patients

Abstract

OBJECTIVE: To compare perioperative glycemic and long-term surgical outcomes in patients undergoing cardiac surgery before and after the recommended 2009 changes in inpatient glycemic targets. RESEARCH DESIGN AND METHODS: We performed a retrospective review of patients who underwent cardiac surgery between 4 September 2007 and 30 April 2011. Comparison was made of blood glucose (BG) outcomes 3 days after surgery, and 30-day cardiac outcomes before and after a change in insulin protocol that took place on 1 September 2009, which consisted of raising the glycemic targets during intravenous insulin infusions from 80-110 mg/dL (80-110 group) to 110-140 mg/dL (110-140 group). RESULTS: When compared with the 80-110 group (n = 667), the 110-140 group (n = 658) had higher mean postoperative BG levels during the intravenous insulin infusion (141 ± 15 vs. 121 ± 15 mg/dL, P < 0.001) and the subcutaneous insulin period (134 ± 24 vs. 130 ± 23 mg/dL, P < 0.001), and for 3 days post operatively (141 ± 17 vs. 127 ± 15 mg/dL, P < 0.001). Fewer patients in the 110-140 mg/dL group experienced moderate hypoglycemia (BG <70 mg/dL) (177 vs. 73, P = 0.04). Severe hypoglycemia (BG <40 mg/dL) occurred in only one patient in the 80-110 group and three patients in the 110-140 group. There were no significant differences in mortality or surgical complication rates (with the exception of reintubation) between the groups. CONCLUSIONS: The higher glycemic target of 110-140 mg/dL resulted in similar mean glucose values, with significantly less hypoglycemia and no significant differences in mortality/morbidity compared with the more strict target of 80-110 mg/dL.