Mark K. Reames

Effect of body mass index on outcomes after cardiac surgery: is there an obesity paradox?

BACKGROUND Numerous studies have documented an obesity paradox in which overweight and obese people with cardiovascular disease have a better prognosis compared with patients with normal body mass index (BMI). This study sought to quantify the effect of BMI on clinical outcomes after cardiac surgery and investigate the obesity paradox. METHODS A concurrent cohort study of 2,440 consecutive patients undergoing cardiac surgery (coronary artery bypass grafting [CABG], valve, or CABG and valve surgery) from January 2004 to December 2008 was carried out. The patients were divided into three groups on the basis of BMI: normal weight (BMI 18.5 to 24.9; n=556; 23%), overweight (BMI 25.0 to 29.9; n=965; 39%), and obese (BMI≥30; n=919; 38%). Multivariable analyses and propensity score matching were used to compare the early and late clinical outcomes among the different BMI groups. RESULTS Overweight patients had a lower operative mortality (odds ratio, 0.4; 95% confidence interval, 0.2 to 0.9; p=0.031) compared with normal BMI patients. Obese patients had a comparable risk for operative mortality (odds ratio, 0.8; 95% confidence interval, 0.4 to 1.6; p=0.47) compared with normal-weight patients. Actuarial 5-year survival was better for the overweight (hazard ratio, 0.5; 95% confidence interval, 0.4 to 0.8; p=0.002) and comparable for the obese (hazard ratio, 0.9; 95% confidence interval, 0.5 to 1.4; p=0.49) groups compared with the normal-weight patients. CONCLUSIONS Overweight patients have better early hospital outcomes and improved survival after cardiac surgery compared with normal BMI patients, supporting the obesity paradox.

Quality Improvement Program Increases Early Tracheal Extubation Rate and Decreases Pulmonary Complications and Resource Utilization After Cardiac Surgery

Abstract  Background: Early tracheal extubation is a common goal after cardiac surgery and may improve postoperative outcomes. Our study evaluates the impact of a quality improvement program (QIP) on early extubation, pulmonary complications, and resource utilization after cardiac surgery. Methods: Between 2002 and 2006, 980 patients underwent early tracheal extubation (<6 hours after surgery) and 1231 had conventional extubation (> 6 hours after surgery, conventional group). Outcomes compared between the two groups included: (1) pneumonia, (2) sepsis, (3) intensive care unit (ICU) length of stay, (4) hospital length of stay, (5) ICU readmission, and (6) reintubation. Logistic regression analysis and propensity score adjustment were used to adjust for imbalances in the patients’ preoperative characteristics. Results: Early extubation rates were significantly increased with QIP (QIP 53% vs. Non‐QIP 38%, p = 0.01). Early extubation was associated with a lower rate of (1) pneumonia (odds ratio [OR]= 0.35, 95% confidence intervals [CI]= 0.22–0.55, p <0.001), (2) sepsis (OR = 0.38, CI = 0.20–0.74, p <0.004), (3) prolonged ICU length of stay (OR = 0.42, CI = 0.35–0.50, p <0.001), (4) hospital length of stay (OR = 0.37, CI = 0.29–0.47, p <0.001), (5) ICU readmission (OR = 0.55, CI = 0.39–0.78, p <0.001), and (6) reintubation (OR = 0.53, CI = 0.34–0.81, p <0.003) both in multivariable logistic regression analysis and propensity score adjustment. Conclusions: QIP and early tracheal extubation reduce pulmonary complications and resource utilization after cardiac surgery.

Is advanced age a contraindication for emergent repair of acute type A aortic dissection

With the general increase in human lifespan, cardiac surgeons are faced with treating an increasing number of elderly patients. The aim of our study was to investigate whether advanced age poses an increased risk for major morbidity and mortality with repair of acute type A aortic dissection. Between 2000 and 2008, 119 patients underwent emergency operation for acute type A aortic dissection at two institutions; 90 were younger than 70 years of age and 29 patients were 70 years or older. Major morbidity, operative and 5-year actuarial survival were compared between groups. The operative mortality rates were comparable between the two groups (18.9% in patients <70 years vs. 24.1% for patients >or=70 years, P=0.6). There was no difference in the rates of reoperation for bleeding (<70 years 31.7% vs. 14.3% for >or=70 years, P=0.09), stroke (18.9% for those <70 years vs. 20.7% for those >or=70 years, P=0.79), acute renal failure (22.2% for those <70 years vs. 17.2% for those >or=70 years, P=0.79) or prolonged ventilation (34.4% for those <70 years vs. 24.1% for those >or=70 years, P=0.36) between the two groups. Actuarial 5-year survival rates were 77% for patients <70 years vs. 59% for patients >or=70 years (P=0.07). The mortality for patients who presented with hemodynamic instability was markedly higher (10 out of 14 patients, 71.4%) compared with the mortality of those who presented with stable hemodynamics (21 out of 88 patients, 23.9%, P<0.001), regardless of age group. No significant differences in operative mortality, major morbidity and actuarial 5-year survival were observed between patients >or=70 years and younger patients although there was a trend toward a lower actuarial 5-year survival in older patients. Surgery for type A acute aortic dissection in patients 70 years or older can be performed with acceptable outcomes. Hemodynamic instability portends a poor prognosis, regardless of age.