Surgical-site infections within 60 days of coronary artery by-pass graft surgery

Surgical wound infections (SWIs) after coronary artery by-pass graft (CABG) within 30 and 60 days of operation were registered. Already known risk factors and possible risk factors for wound infection were studied. SWIs of sternal and/or leg wounds have been reported to occur in 2-20% of patients after CABG. Deep sternal infection, mediastinitis, occurs after 0.5-5% of CABG procedures. The duration and methods of follow-up, as well as definitions of SWI, vary in different studies. Previously known and possible new risk factors were registered for 374 patients. Patients were contacted by telephone 30 and 60 days after surgery and interviewed in accordance with a questionnaire about symptoms and signs of wound infections. Our definition of SWI was based on the Centers for Disease Control and Prevention (CDC) definition. SWIs were diagnosed in 114 of 374 (30.5%) of the patients. In total SWI were diagnosed in 120 surgical-site incisions. Almost all SWIs of the sternum (93.3%) were diagnosed within 30 days of surgery. Most of the SWIs of the leg (73%) were diagnosed within 30 days of surgery and 27% were diagnosed within 31 to 60 days of surgery. Being female was the most important risk factor for SWI of the leg. Low preoperative haemoglobin concentrations were the most important risk factor for superficial SWI on the sternum. Patients with mediastinitis had higher BMI and had more often received erythrocyte transfusions on postoperative day two or later than those without infections.