Objective: Blood loss is a predictor of outcomes after coronary artery bypass grafting (CABG). This study investigated the effects of body mass index (BMI) on blood loss, blood transfusion rate, and the variations in coagulation parameters of Chinese patients undergoing CABG.
Methods: A total of 1007 Chinese patients who consecutively underwent isolated, primary CABG at Fuwai Hospital from January 1, 2013 to December 31, 2013 were included in this study. They were categorized by BMI into <24 kg/m2 (low and normal weight group), 24≤ BMI <28 kg/m2 (overweight group), and BMI ≥28 kg/m2 (obese group). Following this BMI classification, the quantities of blood lost and recorded transfusions were analyzed.
Results: Blood loss and transfusion rates were significantly higher in the low and normal weight group compared with the obese group (p <0.01). Chest tube drainage over 24 h, duration of intensive care unit (ICU) stay, and postoperative mechanical ventilation were higher as well (p <0.01). Atrial fibrillation was closely related to blood transfusion (p <0.001).
Conclusions: Obesity is a predictor for protection against blood loss and transfusion in Chinese people. Patients with low and normal BMI lost more blood per kg of their weight and had higher total transfused volume during isolated primary CABG. Atrial fibrillation was associated with high blood transfusion.
Keywords: BMI; CABG; blood loss; obesity.