Related Experiment Videos
Effects of body size on operative, intermediate, and long-term outcomes after coronary artery bypass operation
T A Schwann1, R H Habib, A Zacharias
1Department of Cardiovascular Surgery, St Vincent Mercy Medical Center and Medical College of Ohio, Toledo, USA.
Insights
Small body size and severe obesity are linked to worse outcomes after coronary artery bypass surgery. Normal body mass index (BMI) patients had the best results, while mild obesity showed no negative impact.
Area of Science:
- Cardiovascular Surgery
- Obesity Research
- Patient Outcomes
Background:
- Investigating the impact of body size on outcomes after coronary artery bypass surgery.
- Understanding the relationship between body mass index (BMI) and surgical results.
Purpose of the Study:
- To determine if body size influences operative and long-term outcomes in patients undergoing coronary artery bypass grafting (CABG).
Main Methods:
- Analysis of 3,560 patients who underwent CABG between 1991 and 1997.
- Patients were categorized by Body Mass Index (BMI).
- Regression analyses and 5-year Kaplan-Meier survival analysis were used to assess outcomes.
Main Results:
- Increased operative mortality, complications, and hospital stay were observed in patients with low BMI (< 24 kg/m²).
- Obesity was associated with higher sternal wound infection rates but not other adverse operative outcomes.
- Both underweight and severely obese patients (BMI > 34 kg/m²) had worse 5-year survival rates, excluding operative mortality.
Conclusions:
- Small body size negatively impacts immediate operative outcomes in CABG patients, potentially due to older age and cardiopulmonary bypass effects.
- While obese patients may have better operative outcomes, severely obese individuals face suboptimal long-term results, likely due to comorbidities like diabetes and hypertension.
Background:
To investigate the role of body size, if any, on operative and longer term outcomes following coronary artery surgery.
Methods:
A total of 3,560 consecutive patients undergoing coronary artery bypass grafting from 1991 to 1997, including 2,401 (67%) males and a mean +/- SD age of 63 +/- 10 years were ranked based on their body mass index (BMI). The association in these patients of preoperative, long-term, and economic data with variations in BMI were studied using regression analyses. Long-term survival was studied using 5-year Kaplan-Meier survival analysis.
Results:
Operative mortality, myocardial infarction, cerebrovascular accidents, blood transfusions, and length of hospital stay were all increased in the smallest patients (BMI < or = 24 kg/m2). Obesity did not increase adverse operative outcomes except for a greater rate of sternal wound infections occurring with increasing severity of obesity. Direct variable costs were lowest in patients clustered around normal BMI, with cost increasing similarly at low and high extremes. This effect was correlated with similar BMI effects on ventilatory and intensive care requirements. Excluding operative mortality, 5-year survival trends were similarly worse for the smallest (BMI < or = 24) and most severely obese (BMI > 34) patients. Mild obesity (BMI > or = 30 to BMI < 34) did not affect long-term survival.
Conclusions:
Among study patients, immediate operative outcomes were adversely affected by small body size, which reflected older age (66 +/- 10 years) and an exaggerated adverse impact of cardiopulmonary bypass. Younger age and smaller effects of cardiopulmonary bypass lead to better operative outcomes in the obese. Long-term outcomes were, however, suboptimal in severely obese patients although that group was the youngest (60 +/- 10 years). In addition to their large body habitus, other factors, including substantial prevalence of diabetes, insulin dependence and hypertension, probably played a significant role in the poor long-term outcome in the severely obese.