Perioperative glycemic control and the risk of infectious complications ina cohort of adults with diabetes

OBJECTIVE: - Although hyperglycemia is hypothesized to increase the short-t erm risk of infection, this hypothesis has not been well tested in a clinic al setting. This study was designed to assess the relationship of periopera tive glycemic control to the subsequent risk of infectious complications. RESEARCH DESIGN AND METHODS- A total of 411 adults with diabetes who underw ent coronary artery surgery from 1990 to 1995 in the cardiac surgery servic e of an urban university hospital were included in a nonconcurrent prospect ive cohort study based on chart review. Perioperative glycemic control was characterized by the mean of six capillary glucose measurements taken durin g the 36-h interval following surgery. The major outcomes studied were. inf ections of leg and chest wounds; pneumonia, and urinary tract infections. RESULTS- Mean postoperative glucose levels ranged from 121 to 352 mg/dl and were divided into quartiles: quartile 1 (121-206 mg/dl), quartile 2 (207-2 29 mg/dl), quartile 3 (230-252 mg/dl), and quartile 4 (253-352 mg/dl). Afte r simultaneous adjustment for age, sex, race, underlying comorbidity acute severity of illness, and the length of the stay in the surgical intensive c are unit, patients with higher mean capillary glucose readings were at incr eased risk of developing infections. Compared with people in the lowest qua rtile of postoperative glucose, those in quartiles 2 (relative odds of infe ction [95% CI] = 1.17 [0.57-2.40]), 3 (1.86 [0.94-3.68]), and 4 (1.78 [0.86 -3.47]) were at progressively higher risk for infection (P = 0.05 for trend ). CONCLUSIONS - In patients with diabetes who undergo coronary artery surgery , postoperative hyperglycemia is an independent predictor of short-term inf ectious complications. Physicians should consider a glucose concentration t arget of less than or equal to 200 mg/dl to reduce the risk of infection.