Reply: Venous Thromboembolism in Body Contouring: An Analysis of 17,774 Patients from the National Surgical Quality Improvement Databases.

479e Reply: Venous Thromboembolism in Body Contouring: An Analysis of 17,774 Patients from the national Surgical Quality Improvement Databases Sir: It was with great interest that we read the comments by Swanson regarding venous thromboembolism in body contouring patients. The author has highlighted a number of critiques of our recent study entitled “Venous Thromboembolism in Body Contouring: An Analysis of 17,774 Patients from the National Surgical Quality Improvement Databases. ”1 We will address each point sequentially. The author first challenges the inclusion of patients undergoing breast contouring procedures, as these patients tend to be younger, thinner, and with shorter operative times. In response to this critique, we draw attention to our study’s statistical methodology. All variables that approached statistical significance in a case-control analysis were included in a bootstrap analysis. Subsequently, a logistic multivariate regression analysis was performed using variables identified in the bootstrap procedure. Notably, these processes have been published on extensively, and validated as tools for deriving prognostic models.2–4 The particularly important component of this methodology is that patient age, body mass index, and anatomical region undergoing contouring (e.g., breast, trunk) were all analyzed independently in sequential multivariate regression models. This allows for discerning between risk associated with procedure type and patient characteristics. The author’s second critique is the high incidence of obesity in our cohort, which he posits is indicative of a large number of bariatric patients. The author cites his own study of 322 body contouring patients to establish the “normal” rate of obesity in a body contouring cohort as 20 percent.5 Our previous work with the National Surgical Quality Improvement Program databases, for the years 2005 to 2010, included a cohort of 1797 patients, and identified approximately 10 percent of the same patients as the current study, and corroborates an obesity incidence of approximately 50 percent.6 In addition, the diversity of this cohort, and the subsequent inclusion of the World Health Organization obesity classification in the venous thromboembolism risk score, permits this tool to be applicable to a wider range of patients, allowing for a better characterization of risk associated with increased body mass index. Dr. Swanson also draws attention to a higher than expected prevalence of wound class and American Society of Anesthesiologists physical status. In response to this point, there is not much that can be said, other than the national data regarding body contouring do not align with the author’s clinical experience. One factor that may be leading to the discrepancy appreciated by the author, though, is the Current Procedural Terminology coding of large ones that do not include objective diagnostic data (and are affected by sampling bias),1 are unlikely to be fruitful. Our efforts are better directed at (1) improving anesthesia to reduce risk for all patients8 and (2) learning more about the natural history of this complication using ultrasound surveillance, which can also provide early detection and treatment for affected patients.9 DOI: 10.1097/01.prs. 0000475809.12542. ef