Preventing Surgical Site Infections: Is it just too Sweet?

Abstract

Dear Editor, We read with interest the article by Diana et al. [1] on measures to prevent surgical site infections (SSI) by surgeons. The survey reported that nutritional screening is being regularly conducted by 50% of surgeons before major surgery. It also found widely differing strategies adopted by surgeons to prevent SSI, with low adherence to the National Institute for Health and Clinical Excellence of the United Kingdom (NICE) guidelines. It is well known that diabetic patients who undergo cardiac surgery have greater perioperative mortality and morbidity, including SSI, compared with nondiabetic patients. For patients in noncardiac surgical specialties, the association between diabetes and morbidity is less clear. In a recent study, we found that in our database of 1,343 surgical patients, those with diabetes had a 1.6 times greater risk of postoperative complications than did patients without diabetes [2]. In addition, the data affirm the relationship between the presence of diabetes and SSI in cardiac surgical patients in the Chinese Asian population [3]. However, it may not be a simple matter of whether the patient has diabetes or not, but good perioperative blood glucose control can be equally important. Numerous studies in cardiac and noncardiac surgical patients have supported tight glucose control in the perioperative period, for example by continuous insulin infusion, to reduce morbidity and SSI. Such measures may also benefit nondiabetic patients undergoing major surgery, as it has been found that the blood glucose levels in this population can rise significantly at induction of anesthesia until the early postoperative period [4]. Clearly, some of these patients may have had undiagnosed glucose intolerance or diabetes in the first instance. Interestingly, a recent Cochrane Systematic Review in 2009 found that there is insufficient evidence to support strict perioperative glycemic control for prevention of SSI in adults [5]. The conclusion was based on five randomized controlled trials that are heterogeneous and cannot be incorporated into a metaanalysis. A review of our own database (and available evidence) has led us to adopt the use of continuous insulin sliding scale for all cardiac and noncardiac patients undergoing major surgery in order to improve perioperative blood glucose control. Apart from nutritional screening, we would also advocate diabetic screening, which may help identify those susceptible to SSI. As suggested by the Cochrane Review, large, well-conducted randomized trials are required to answer the question of whether these measures can truly reduce SSI.