Study questions relevance of benchmarks among CABG patients receiving insulin infusions

Achieving Surgical Care Improvement Project benchmarks for glycemic control may be unnecessary for patients undergoing CABG when perioperative continuous insulin infusion protocols are implemented.

National guidelines mandate that all CABG patients receive an IV insulin infusion when necessary to maintain blood glucose levels of <200 mg/dL in the postoperative period. The Surgical Care Improvement Project (SCIP) benchmarked 6 a.m. blood glucose of <200 mg/dL on postoperative days 1 and 2 as a quality measure of glycemic care in cardiac surgery to be used for reporting of operative outcomes and monetary reimbursement.

A team of researchers in cardiothoracic surgery and endocrinology at Boston Medical Center studied 833 patients who underwent CABG surgery and received continuous insulin infusions to maintain serum blood glucose levels of ,180 mg/dL between January 2006 and April 2011. Patients were divided into two groups depending on whether they were compliant with SCIP or whether they were an outlier.

Study results showed an incidence of 6.6% among SCIP outliers. Outliers were more likely to have diabetes (76% vs. 33%; P<.0001), a higher HbA1c level (8.7% vs. 7.59%; P<.0009), increased BMI (31.1 vs. 29.2; P=.03) and lower ejection fraction (49% vs. 53%; P=.06). However, researchers found that SCIP outliers experienced no increase in morbidity, mortality or hospital length of stay.

“We found that these patients may have had excellent glycemic control except for that one 6 a.m. glucose level. On the other hand, we saw patients who had poor glycemic control but just happened to have a glucose level of less than 200 mg/dL at the two time periods measured by SCIP,” Harold Lazar, MD, a cardiothoracic surgeon at Boston Medical Center, said in a press release.

According to the researchers, these findings may have national implications and may result in changes in guidelines for glycemic control.

“We think that glycemic control is important in all CABG patients,” Lazer stated. “However, current Surgical Care Improvement Project guidelines are not an accurate method to determine whether hospitals are truly compliant with meeting the goals of glycemic control.”

For more information:

McDonnell MM. Relevance of the surgical care improvement project on glycemic control in CABG patients receiving continuous insulin infusions. Presented at: the 2012 American Association for Thoracic Surgery Annual Meeting; April 28-May 2, 2012; San Francisco.

Disclosure: Dr. Lazar reports no relevant financial disclosures.