COSMETIC Outcomes Article
Venous Thromboembolism in Body Contouring: An Analysis of 17,774 Patients from the National Surgical Quality Improvement Databases Ari M. Wes, B.A. Jason D. Wink, M.D., M.T.R. Stephen J. Kovach, M.D. John P. Fischer, M.D. Philadelphia, Pa.
Background: The purpose of this study was to examine the incidence and predictors of venous thromboembolism following body contouring. Methods: The authors reviewed the American College of Surgeons National Surgical Quality Improvement Program database from 2005 to 2012 for all body contouring cases. A multivariate logistic regression was performed to determine predictors of venous thromboembolism, and used to define risk scores for each significant predictor. Results: Seventeen thousand seven hundred seventy-four patients underwent body contouring during the study period. Venous thromboembolism occurred in 99 individuals (0.56 percent). Multivariate logistic regression revealed that age older than 45 years [45 to 60 years (OR, 1.54; p = 0.1); older than 60 years (OR 3.1, p < 0.001)], undergoing contouring of the trunk (OR, 2.75; p < 0.001), obesity [body mass index of 30 to 34.9 (OR, 3.35; p < 0.001); body mass index of 35 to 39.9 (OR, 4.41; p < 0.001); body mass index ≥ 40 (OR, 3.14; p = 0.001)], and admission on an inpatient basis (OR, 3.01; p < 0.001) were associated with increased odds of venous thromboembolism. Patients’ total scores were categorized as low (0 to 4), medium (5 to 7), or high risk (8 to 9). The low-risk cohort exhibited a venous thromboembolism incidence of 0.14 percent, the medium-risk cohort experienced an incidence of 0.97 percent, and the high-risk group experienced a venous thromboembolism incidence of 2.95 percent. Conclusions: This study identifies predictors of venous thromboembolism and creates a simple risk-scoring model using a large, prospective data set. The authors' analysis demonstrates that in the presence of certain risk factors, the incidence of venous thromboembolism increases dramatically; in these cases, venous thromboembolism prophylaxis may be warranted. (Plast. Reconstr. Surg. 135: 972e, 2015.) CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.
V
enous thromboembolism represents one of the most preventable causes of death in hospitalized patients, yet compliance with
From the Division of Plastic Surgery, Hospital of the University of Pennsylvania. Received for publication July 27, 2014; accepted December 3, 2014. Deidentified patient information is freely available to all institutional members who comply with the American College of Surgeons National Surgical Quality Improvement Program Data Use Agreement. The Data Use Agreement implements the protections afforded by the Health Insurance Portability and Accountability Act of 1996. Copyright © 2015 by the American Society of Plastic Surgeons DOI: 10.1097/PRS.0000000000001251
972e
prophylaxis standards set by the American College of Chest Physicians is highly varied within the field of plastic surgery.1–3 Together, these facts become more significant when considering evidence that suggests venous thromboembolism prophylaxis adds little risk of surgical bleeding.4 In breast reconstruction, the incidence and risk factors associated with venous thromboembolism have been shown to be reconstruction type, increased operative time, and obesity.5 In body Disclosure: None of the authors listed has any conflicts of interest to report. This particular research received no internal or external grant funding.
www.PRSJournal.com
Copyright © 2015 American Society of Plastic Surgeons. Unauthorized reproduction of this article is prohibited.
Volume 135, Number 6 • Venous Thromboembolism in Body Contouring contouring, another rapidly growing area of plastic surgery, some studies have attempted to delineate key risk factors associated with postoperative venous thromboembolism. However, these studies lack generalizability because of their single- surgeon or single-institution design.6,7 In addition, the relative infrequency with which venous thromboembolism events occur makes conducting an adequately powered study very difficult. This current study addresses the aforementioned issues through the use of the American College of Surgeons National Surgical Quality Improvement Program databases. Body contouring is often performed on patients with multiple comorbidities and carries with it a significant postoperative recovery and the potential for limited mobility. It is imperative that we more accurately risk-stratify these patients. Complications as a whole have been analyzed in body contouring patients using a large national data set.8 Potentially because of the disparate nature of the medical complications that were clustered in the aforementioned analysis, however, increased body mass index was the only significant predictor of medical complications. We hypothesize that an indepth analysis of venous thromboembolism—specifically, in patients undergoing body contouring procedures—will yield multiple significant predictors of risk, that will have the potential to influence medical management of certain high-risk patients.
PATIENTS AND METHODS Institutional review board exemption was approved by our institution. Patients who underwent body contouring procedures were identified from the American College of Surgeons National Surgical Quality Improvement Program databases between the years 2005 and 2012 (n = 17,774). The Current Procedural Terminology codes for surgical contouring of the thigh (15832), leg (15833), hip (15834), buttocks (15835), arm (15836), and abdomen (15847 and 15830); and those for mastopexy (19316), mammaplasty (19318), and suction-assisted-lipectomy (15876 to 15879) were used to identify patients who met inclusion criteria. Patients younger than 18 years were excluded. American College of Surgeons National Surgical Quality Improvement Program data are collected by trained nurses at participating institutions, using a systematic sampling of general and vascular operations performed. Audits of the database have found a disagreement rate of 1.8 percent with respect to various program variables. To ensure a 30-day follow-up period, patients are
contacted by letter or telephone survey following discharge. The list and definitions of variables collected in the database can be found at the American College of Surgeons National Surgical Quality Improvement Program Web site (http://www. acsnsqip.org/). Data were accessed on December 1, 2013. Using predefined American College of Surgeons National Surgical Quality Improvement Program variables, body mass index (in kilograms per square meter) was calculated for each encounter, and categorized using the World Health Organization Obesity Classifications as follows: nonobese (body mass index < 30 kg/m2), class I obesity (body mass index of 30 to 34.9 kg/m2), class II obesity (body mass index of 35.0 to 39.9 kg/m2), and class III obesity (body mass index ≥ 40 kg/m2).9,10 An albumin value less than 3.5 g/dl was considered malnutrition. Patients were also stratified by the number of contouring procedures received and the anatomical regions where contouring took place. Whether or not patients had recently experienced massive weight loss was also noted. Lastly, procedures were categorized as inpatient or outpatient, and by the surgical specialty performing the operation. Outcomes and Statistical Analysis The primary outcome of interest was venous thromboembolism, which included deep venous thrombosis and pulmonary embolism. To analyze predictors of venous thromboembolism, patients who experienced venous thromboembolism were compared to those who did not. Pearson’s chisquared and Fisher’s exact tests were used to analyze categorical variables; Wilcoxon rank sum and Kruskal-Wallis tests were used for continuous variables. A bootstrap analysis was then performed to identify and validate the set of variables that should remain in the final risk model.11 The bootstrap procedure consisted of the following: 1000 random samples were generated from the entire cohort of patients with replacement. These samples then underwent stepwise multivariate logistic regression. Frequencies of occurrence of each variable in the final model were noted, and variables were retained in the final multivariate regression analysis if they occurred in over 50 percent of the bootstrap models.12,13 Risk scores for each variable were then calculated by rounding all beta coefficients and dividing by their greatest common denominator, to obtain clinically useful round numbers that could serve as prognosticators of risk. Each patient’s total venous thromboembolism risk score was calculated by adding the individual risk scores
973e Copyright © 2015 American Society of Plastic Surgeons. Unauthorized reproduction of this article is prohibited.
Plastic and Reconstructive Surgery • June 2015 for all of the risk factors present. Patients were then grouped by their total venous thromboembolism risk scores into low-, medium-, and highrisk cohorts, for which venous thromboembolism incidences were calculated. All tests were twotailed and statistical significance was defined as p < 0.05. All analyses were performed using STATA IC 11.0 (StataCorp, College Station, Texas).
RESULTS Seventeen thousand seven hundred seventyfour patients underwent body contouring during the study period; 94.6 percent of the cohort were women, and the majority of patients [n = 8916 (50.2 percent)] were between 45 and 65 years of age. The most common areas of intervention were the breast [n = 11,881 (66.8 percent)] and abdominal [n = 5501 (30.9 percent)] regions. Sixteen thousand three hundred six patients (91.7 percent) underwent an isolated contouring procedure, whereas 1293 (7.3 percent) underwent two procedures, and 175 (1.0 percent) underwent three. Approximately two-thirds of the cohort underwent body contouring procedures in an outpatient Table 1. Demographic and Operative Characteristics of Patients Undergoing Body Contouring from 2005 to 2012 Identified in the National Surgical Quality Improvement Program Data Sets Characteristic No. of patients Sex Female Male Age group 65 yr Race White Black Hispanic Asian Other Suction-assisted lipectomy Contouring of extremities Contouring of trunk Contouring of breast Areas of body 1 2 >2 Treatment Outpatient Inpatient Surgical specialty Plastics General Operative time ± SD, min Total length of stay ± SD, days
No. (%) 17,774 16,806 (94.6) 968 (5.4) 6840 (38.5) 8916 (50.2) 2018 (11.4) 10,147 (57.1) 2106 (11.8) 1077 (6.1) 179 (1.0) 69 (0.4) 1563 (8.8) 199 (1.1) 5528 (31.1) 11,881 (66.8) 16,306 (91.7) 1293 (7.3) 175 (1.0) 11,628 (65.4) 6146 (34.6) 12,348 (69.5) 5426 (30.5) 173.5 ± 89.2 1.7 ± 7.2
setting [n = 11,628 (65.4 percent)], and just over two-thirds of the cases were performed by plastic surgeons [n = 12,348 (69.5 percent)] (Table 1). The average body mass index of patients undergoing body contouring was 31.4 kg/m2, whereas 2137 individuals were morbidly obese (body mass index ≥ 40 kg/m2). Hypertension was the most common comorbidity [n = 5295 (29.8 percent)] in the cohort, followed by history of dyspnea [n = 832 (4.7 percent)]. Mean operative time was 173.5 ± 89.2 minutes, and mean length of hospital stay was 1.7 ± 7.2 days (Table 2). Overall, 99 patients (0.56 percent) experienced venous thromboembolism postoperatively. Forty-six of these patients experienced deep venous thrombosis, 44 suffered from pulmonary embolism, and nine patients experienced both of these phenomena postoperatively. Univariate analysis, wherein patients who experienced venous thromboembolism were compared to those who did not, identified a number of significant differences between the cohorts. The venous thromboembolism cohort had significantly more male patients and patients older than 65 years, more cases of trunk contouring, fewer cases of breast contouring, and more cases of multiregion contouring. More of the venous thromboembolism cohort underwent contouring on an inpatient basis, was operated on by a general surgeon, and was obese (Table 3). In addition, the venous thromboembolism cohort had significantly higher rates of diabetes, hypertension, dyspnea, malnutrition, and unclean wound class; increased American Society of Anesthesiologists classification; increased operative time; and increased length of stay (Table 4). A multivariate logistic regression was then performed to identify independent predictors of venous thromboembolism. This analysis revealed that age older than 45 years [45 to 60 years (OR, 1.54; p = 0.1); older than 60 years (OR, 3.1; p < 0.001)], undergoing contouring of the trunk (OR, 2.75; p < 0.001)], obesity [body mass index of 30 to 34.9 (OR, 3.35; p < 0.001); body mass index of 35 to 39.9 (OR, 4.41; p < 0.001); body mass index ≥ 40 (OR, 3.14; p = 0.001)], and admission on an inpatient basis (OR, 3.01; p < 0.001) were associated with increased odds of venous thromboembolism (Table 5). Rounded risk scores were then assigned to each of these variables that were significant in our final multivariate regression analysis as described above under Patients and Methods (Table 6). The variable that was associated with the highest beta coefficient, body mass index greater than 35, was assigned a risk score of 3. The variables associated with smaller but still very significant beta
974e Copyright © 2015 American Society of Plastic Surgeons. Unauthorized reproduction of this article is prohibited.
Volume 135, Number 6 • Venous Thromboembolism in Body Contouring Table 2. Summary of Characteristics of Patients Undergoing Body Contouring from 2005 to 2012 Identified in the National Surgical Quality Improvement Program Data Sets
Table 3. Bivariate Analysis of Demographic and Operative Characteristics Associated with Venous Thromboembolism
Characteristic
Total Sex Female Male Age group 65 yr Race White Black Hispanic Asian Other Suction-assisted lipectomy Contouring of extremities Contouring of trunk Contouring of breast Areas of body 1 2 >2 Treatment Outpatient Inpatient Surgical specialty Plastics General Operative time ± SD, min Total length of stay ± SD, days
No. of patients BMI WHO obesity stratification 0 (40 kg/m2) Diabetes Type 1 Type 2 Active smoking Functional status Independent Partially dependent Totally dependent Previous coronary intervention Prior cardiac surgery History of angina History of hypertension History of dyspnea Current use of steroids Recent weight loss (>10% in 6 mo) Bleeding disorder Malnutrition (albumin
Venous Thromboembolism in Body Contouring: An Analysis of 17,774 Patients from the National Surgical Quality Improvement Databases Ari M. Wes, B.A. Jason D. Wink, M.D., M.T.R. Stephen J. Kovach, M.D. John P. Fischer, M.D. Philadelphia, Pa.
Background: The purpose of this study was to examine the incidence and predictors of venous thromboembolism following body contouring. Methods: The authors reviewed the American College of Surgeons National Surgical Quality Improvement Program database from 2005 to 2012 for all body contouring cases. A multivariate logistic regression was performed to determine predictors of venous thromboembolism, and used to define risk scores for each significant predictor. Results: Seventeen thousand seven hundred seventy-four patients underwent body contouring during the study period. Venous thromboembolism occurred in 99 individuals (0.56 percent). Multivariate logistic regression revealed that age older than 45 years [45 to 60 years (OR, 1.54; p = 0.1); older than 60 years (OR 3.1, p < 0.001)], undergoing contouring of the trunk (OR, 2.75; p < 0.001), obesity [body mass index of 30 to 34.9 (OR, 3.35; p < 0.001); body mass index of 35 to 39.9 (OR, 4.41; p < 0.001); body mass index ≥ 40 (OR, 3.14; p = 0.001)], and admission on an inpatient basis (OR, 3.01; p < 0.001) were associated with increased odds of venous thromboembolism. Patients’ total scores were categorized as low (0 to 4), medium (5 to 7), or high risk (8 to 9). The low-risk cohort exhibited a venous thromboembolism incidence of 0.14 percent, the medium-risk cohort experienced an incidence of 0.97 percent, and the high-risk group experienced a venous thromboembolism incidence of 2.95 percent. Conclusions: This study identifies predictors of venous thromboembolism and creates a simple risk-scoring model using a large, prospective data set. The authors' analysis demonstrates that in the presence of certain risk factors, the incidence of venous thromboembolism increases dramatically; in these cases, venous thromboembolism prophylaxis may be warranted. (Plast. Reconstr. Surg. 135: 972e, 2015.) CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.
V
enous thromboembolism represents one of the most preventable causes of death in hospitalized patients, yet compliance with
From the Division of Plastic Surgery, Hospital of the University of Pennsylvania. Received for publication July 27, 2014; accepted December 3, 2014. Deidentified patient information is freely available to all institutional members who comply with the American College of Surgeons National Surgical Quality Improvement Program Data Use Agreement. The Data Use Agreement implements the protections afforded by the Health Insurance Portability and Accountability Act of 1996. Copyright © 2015 by the American Society of Plastic Surgeons DOI: 10.1097/PRS.0000000000001251
972e
prophylaxis standards set by the American College of Chest Physicians is highly varied within the field of plastic surgery.1–3 Together, these facts become more significant when considering evidence that suggests venous thromboembolism prophylaxis adds little risk of surgical bleeding.4 In breast reconstruction, the incidence and risk factors associated with venous thromboembolism have been shown to be reconstruction type, increased operative time, and obesity.5 In body Disclosure: None of the authors listed has any conflicts of interest to report. This particular research received no internal or external grant funding.
www.PRSJournal.com
Copyright © 2015 American Society of Plastic Surgeons. Unauthorized reproduction of this article is prohibited.
Volume 135, Number 6 • Venous Thromboembolism in Body Contouring contouring, another rapidly growing area of plastic surgery, some studies have attempted to delineate key risk factors associated with postoperative venous thromboembolism. However, these studies lack generalizability because of their single- surgeon or single-institution design.6,7 In addition, the relative infrequency with which venous thromboembolism events occur makes conducting an adequately powered study very difficult. This current study addresses the aforementioned issues through the use of the American College of Surgeons National Surgical Quality Improvement Program databases. Body contouring is often performed on patients with multiple comorbidities and carries with it a significant postoperative recovery and the potential for limited mobility. It is imperative that we more accurately risk-stratify these patients. Complications as a whole have been analyzed in body contouring patients using a large national data set.8 Potentially because of the disparate nature of the medical complications that were clustered in the aforementioned analysis, however, increased body mass index was the only significant predictor of medical complications. We hypothesize that an indepth analysis of venous thromboembolism—specifically, in patients undergoing body contouring procedures—will yield multiple significant predictors of risk, that will have the potential to influence medical management of certain high-risk patients.
PATIENTS AND METHODS Institutional review board exemption was approved by our institution. Patients who underwent body contouring procedures were identified from the American College of Surgeons National Surgical Quality Improvement Program databases between the years 2005 and 2012 (n = 17,774). The Current Procedural Terminology codes for surgical contouring of the thigh (15832), leg (15833), hip (15834), buttocks (15835), arm (15836), and abdomen (15847 and 15830); and those for mastopexy (19316), mammaplasty (19318), and suction-assisted-lipectomy (15876 to 15879) were used to identify patients who met inclusion criteria. Patients younger than 18 years were excluded. American College of Surgeons National Surgical Quality Improvement Program data are collected by trained nurses at participating institutions, using a systematic sampling of general and vascular operations performed. Audits of the database have found a disagreement rate of 1.8 percent with respect to various program variables. To ensure a 30-day follow-up period, patients are
contacted by letter or telephone survey following discharge. The list and definitions of variables collected in the database can be found at the American College of Surgeons National Surgical Quality Improvement Program Web site (http://www. acsnsqip.org/). Data were accessed on December 1, 2013. Using predefined American College of Surgeons National Surgical Quality Improvement Program variables, body mass index (in kilograms per square meter) was calculated for each encounter, and categorized using the World Health Organization Obesity Classifications as follows: nonobese (body mass index < 30 kg/m2), class I obesity (body mass index of 30 to 34.9 kg/m2), class II obesity (body mass index of 35.0 to 39.9 kg/m2), and class III obesity (body mass index ≥ 40 kg/m2).9,10 An albumin value less than 3.5 g/dl was considered malnutrition. Patients were also stratified by the number of contouring procedures received and the anatomical regions where contouring took place. Whether or not patients had recently experienced massive weight loss was also noted. Lastly, procedures were categorized as inpatient or outpatient, and by the surgical specialty performing the operation. Outcomes and Statistical Analysis The primary outcome of interest was venous thromboembolism, which included deep venous thrombosis and pulmonary embolism. To analyze predictors of venous thromboembolism, patients who experienced venous thromboembolism were compared to those who did not. Pearson’s chisquared and Fisher’s exact tests were used to analyze categorical variables; Wilcoxon rank sum and Kruskal-Wallis tests were used for continuous variables. A bootstrap analysis was then performed to identify and validate the set of variables that should remain in the final risk model.11 The bootstrap procedure consisted of the following: 1000 random samples were generated from the entire cohort of patients with replacement. These samples then underwent stepwise multivariate logistic regression. Frequencies of occurrence of each variable in the final model were noted, and variables were retained in the final multivariate regression analysis if they occurred in over 50 percent of the bootstrap models.12,13 Risk scores for each variable were then calculated by rounding all beta coefficients and dividing by their greatest common denominator, to obtain clinically useful round numbers that could serve as prognosticators of risk. Each patient’s total venous thromboembolism risk score was calculated by adding the individual risk scores
973e Copyright © 2015 American Society of Plastic Surgeons. Unauthorized reproduction of this article is prohibited.
Plastic and Reconstructive Surgery • June 2015 for all of the risk factors present. Patients were then grouped by their total venous thromboembolism risk scores into low-, medium-, and highrisk cohorts, for which venous thromboembolism incidences were calculated. All tests were twotailed and statistical significance was defined as p < 0.05. All analyses were performed using STATA IC 11.0 (StataCorp, College Station, Texas).
RESULTS Seventeen thousand seven hundred seventyfour patients underwent body contouring during the study period; 94.6 percent of the cohort were women, and the majority of patients [n = 8916 (50.2 percent)] were between 45 and 65 years of age. The most common areas of intervention were the breast [n = 11,881 (66.8 percent)] and abdominal [n = 5501 (30.9 percent)] regions. Sixteen thousand three hundred six patients (91.7 percent) underwent an isolated contouring procedure, whereas 1293 (7.3 percent) underwent two procedures, and 175 (1.0 percent) underwent three. Approximately two-thirds of the cohort underwent body contouring procedures in an outpatient Table 1. Demographic and Operative Characteristics of Patients Undergoing Body Contouring from 2005 to 2012 Identified in the National Surgical Quality Improvement Program Data Sets Characteristic No. of patients Sex Female Male Age group 65 yr Race White Black Hispanic Asian Other Suction-assisted lipectomy Contouring of extremities Contouring of trunk Contouring of breast Areas of body 1 2 >2 Treatment Outpatient Inpatient Surgical specialty Plastics General Operative time ± SD, min Total length of stay ± SD, days
No. (%) 17,774 16,806 (94.6) 968 (5.4) 6840 (38.5) 8916 (50.2) 2018 (11.4) 10,147 (57.1) 2106 (11.8) 1077 (6.1) 179 (1.0) 69 (0.4) 1563 (8.8) 199 (1.1) 5528 (31.1) 11,881 (66.8) 16,306 (91.7) 1293 (7.3) 175 (1.0) 11,628 (65.4) 6146 (34.6) 12,348 (69.5) 5426 (30.5) 173.5 ± 89.2 1.7 ± 7.2
setting [n = 11,628 (65.4 percent)], and just over two-thirds of the cases were performed by plastic surgeons [n = 12,348 (69.5 percent)] (Table 1). The average body mass index of patients undergoing body contouring was 31.4 kg/m2, whereas 2137 individuals were morbidly obese (body mass index ≥ 40 kg/m2). Hypertension was the most common comorbidity [n = 5295 (29.8 percent)] in the cohort, followed by history of dyspnea [n = 832 (4.7 percent)]. Mean operative time was 173.5 ± 89.2 minutes, and mean length of hospital stay was 1.7 ± 7.2 days (Table 2). Overall, 99 patients (0.56 percent) experienced venous thromboembolism postoperatively. Forty-six of these patients experienced deep venous thrombosis, 44 suffered from pulmonary embolism, and nine patients experienced both of these phenomena postoperatively. Univariate analysis, wherein patients who experienced venous thromboembolism were compared to those who did not, identified a number of significant differences between the cohorts. The venous thromboembolism cohort had significantly more male patients and patients older than 65 years, more cases of trunk contouring, fewer cases of breast contouring, and more cases of multiregion contouring. More of the venous thromboembolism cohort underwent contouring on an inpatient basis, was operated on by a general surgeon, and was obese (Table 3). In addition, the venous thromboembolism cohort had significantly higher rates of diabetes, hypertension, dyspnea, malnutrition, and unclean wound class; increased American Society of Anesthesiologists classification; increased operative time; and increased length of stay (Table 4). A multivariate logistic regression was then performed to identify independent predictors of venous thromboembolism. This analysis revealed that age older than 45 years [45 to 60 years (OR, 1.54; p = 0.1); older than 60 years (OR, 3.1; p < 0.001)], undergoing contouring of the trunk (OR, 2.75; p < 0.001)], obesity [body mass index of 30 to 34.9 (OR, 3.35; p < 0.001); body mass index of 35 to 39.9 (OR, 4.41; p < 0.001); body mass index ≥ 40 (OR, 3.14; p = 0.001)], and admission on an inpatient basis (OR, 3.01; p < 0.001) were associated with increased odds of venous thromboembolism (Table 5). Rounded risk scores were then assigned to each of these variables that were significant in our final multivariate regression analysis as described above under Patients and Methods (Table 6). The variable that was associated with the highest beta coefficient, body mass index greater than 35, was assigned a risk score of 3. The variables associated with smaller but still very significant beta
974e Copyright © 2015 American Society of Plastic Surgeons. Unauthorized reproduction of this article is prohibited.
Volume 135, Number 6 • Venous Thromboembolism in Body Contouring Table 2. Summary of Characteristics of Patients Undergoing Body Contouring from 2005 to 2012 Identified in the National Surgical Quality Improvement Program Data Sets
Table 3. Bivariate Analysis of Demographic and Operative Characteristics Associated with Venous Thromboembolism
Characteristic
Total Sex Female Male Age group 65 yr Race White Black Hispanic Asian Other Suction-assisted lipectomy Contouring of extremities Contouring of trunk Contouring of breast Areas of body 1 2 >2 Treatment Outpatient Inpatient Surgical specialty Plastics General Operative time ± SD, min Total length of stay ± SD, days
No. of patients BMI WHO obesity stratification 0 (40 kg/m2) Diabetes Type 1 Type 2 Active smoking Functional status Independent Partially dependent Totally dependent Previous coronary intervention Prior cardiac surgery History of angina History of hypertension History of dyspnea Current use of steroids Recent weight loss (>10% in 6 mo) Bleeding disorder Malnutrition (albumin
