Can Higher Body Mass Index Patients Save Blood Following On-pump Coronary Artery Bypass Grafting?

Background

The association of obesity with postoperative bleeding volume and transfusions after coronary artery bypass grafting (CABG) is not clear. We evaluated the effects of body mass index (BMI) on bleeding volume and transfusions in patients undergoing on-pump CABG.

Methods

We investigated 1,050 patients, aged 24 years to 83 years, who underwent isolated, primary CABG with cardiopulmonary bypass (CPB) at Fuwai Hospital, Chinese Academy of Medical Sciences, from September 2017 to July 2018. We recorded preoperative medical and laboratory coagulation parameters, intraoperative data, and postoperative bleeding volume for 24 hours following surgery. Primary endpoint was bleeding volume within 24 hours and transfusions after surgery. We analyzed the correlation between bleeding volume within 24 hours and transfusions after surgery and preoperative data with univariate and multivariate linear regression and logistic regression.

Results

Old age significantly increased postoperative transfusions (OR = 1.035 95% CI 1.013-1.058, P = .002), whereas higher BMI (OR = 0.897 95% CI 0.848-0.949,
P < .001) and higher hemoglobin (HGB) (OR = 0.966 95% CI 0.954-0.978, P < 0.001) decreased postoperative transfusions. And, BMI independently was correlated with bleeding volume after multivariate regression analysis
(B = -0.257, P < .001).

Conclusions

Our findings suggest higher BMI may reduce postoperative bleeding volume and transfusion rate, thus such patients may save blood products during on-pump CABG.