Objective: To assess whether obesity is a risk factor for morbidity and mortality in patients undergoing elective coronary artery revascularization.
Design: Prospective, clinical study.
Setting: University hospital.
Participants: Three hundred forty-five consecutive patients who underwent elective coronary revascularization with cardiopulmonary bypass and without associated procedures.
Interventions: Patients were assigned to the obese group if their body mass index was greater than 30 for men and 28.6 for women, according to the World Health Organization indications.
Measurements and main results: Preoperative and intraoperative variables were collected and checked for homogeneity of the groups. Postoperative outcome was assessed on the basis of intubation time, intensive care unit (ICU) and postoperative hospital stay, mortality rate, and incidence of transfusions, reoperations, low-output syndrome, minor and major neurologic dysfunction, minor and major lung dysfunctions, renal dysfunction, and superficial and deep infections. The effect of obesity on postoperative outcome was tested with a multivariate logistic regression analysis. Obese and control patients had the same intubation time and ICU and postoperative hospital stay. Mortality and all major complications occurred with the same incidence in the two groups. Obese patients had a significantly (p < 0.05) greater rate of superficial infections and more (24.1% v 7.4%; p < 0.001) minor lung complications. Conversely, they had a significantly lower transfusion rate (27.5% v42.7%; p < 0.01).
Conclusion: Obese patients had only minor complications after coronary artery surgery. The large body surface area because of obesity protects them against the hemodilution-related transfusion risk.