Body surface area: a new predictor factor for conversion and prolonged operative time in laparoscopic colorectal surgery

Anthropometric measures of obesity in patients with knee joint pathology: Body surface area versus body mass index

BACKGROUND

Obesity is quantified using body mass index. Body surface area may provide a superior and more anthropometric method of quantifying obesity in patients with musculoskeletal knee disease. This study compares the effect of weight, height, age and gender on body mass index and body surface area in a population with orthopaedic knee disease.

METHODS

An observational cohort study was conducted of patients presenting with musculoskeletal knee disease. Associations between body mass index, body surface area, age, gender, height, weight and operative versus non-operative management were analysed.

RESULTS

A total of 151 patients were included. Body surface area was more strongly correlated to weight than body mass index (r = 0.98, p < 0.001 versus r = 0.84, p < 0.001). Body surface area also reflects height which body mass index under presents (r = 0.65, p < 0.001 versus r = -0.08, p = 0.35). Body mass index and body surface area were correlated with one another (r = 0.70, p < 0.001). Age was inversely correlated with body surface area (r = -0.20, p = 0.013) but not body mass index (r = 0.05, p = 0.585). Body mass index did not differ between males and females (30.1 versus 30.9, p = 0.37); however, BSA scores were significantly higher in males than females (2.11 versus 1.91, p < 0.001). Neither body surface area nor body mass index scores influenced operative versus non-operative treatment.

CONCLUSION

Body surface area could be a useful alternative to body mass index when considering obesity in patients with musculoskeletal knee pathology. Body surface area better reflects the effects of height, weight, age and gender than body mass index.

The Association Between Body Mass Index and Death Following Elective Endovascular and Open Repair of Abdominal Aortic Aneurysms in the Vascular Quality Initiative

OBJECTIVE

The effect of body mass index (BMI) on post-operative outcomes after abdominal aortic aneurysm (AAA) repair remains poorly defined. The association between BMI and death following elective endovascular aneurysm repair (EVAR) and open aneurysm repair (OAR) of AAA in a large national quality registry is investigated.

METHODS

All elective AAA repairs within the Society for Vascular Surgery Vascular Quality Initiative (VQI; 2010 to September 2021) were reviewed (EVAR, n = 53 426; OAR, n = 9 479). All analyses were conducted separately for EVAR and OAR patients. The primary end points were 30 day mortality and five year survival rates. Study cohorts were divided into World Health Organisation BMI categories (C1 < 18.5, C2 18.5 ≤ BMI < 25, C3 25 ≤ BMI < 30, C4, 30 ≤ BMI < 35, C5 35 ≤ BMI < 40, C6 ≥ 40). BMI was examined as both a categorical and continuous variable. Logistic and Cox proportional hazards regression were used for risk adjustment.

RESULTS

Among EVAR patients, BMI distribution was C1, 1 216 (2%); C2, 14 687 (28%); C3, 20 516 (38%); C4, 11 352 (21%); C5, 3 947 (7%); C6, 1 708 (3%). Class 1, 2, and 6 BMI patients experienced an increased 30 day mortality rate (C1 2.6%; C2 1.3%; C6 1.4% vs. C3 - 5 0.7%; p < .001) and C1 and C2 had correspondingly inferior long term survival (five years: C1 69 ± 3%; C2 79 ± 1% vs. C3 - 6 86 - 88 ± 2%; log rank p < .001). These survival disparities persisted after risk adjustment for multiple confounders. In the OAR cohort, BMI distribution was C1, 280 (3%); C2, 2 862 (30%); C3, 3 587 (38%); C4, 1 940 (21%); C5, 581 (6%); C6, 229 (2%). Crude 30 day mortality rates were increased for both the lowest and highest BMI patients (C1 12%, C6 7% vs. C2 - 5 3 - 4%; p < .001); these differences also persisted in long term survival (five years: C1 71 ± 6%, C6 82 ± 6% vs. C2 - 6 85 - 88 ± 3%; log rank p < .001). In risk adjusted analysis, both low and high BMI OAR patients had an increased 30 day and long term mortality rate.

CONCLUSION

Within the VQI, both the extreme low (< 18.5) and high (≥ 40) BMI groups experienced an increased 30 day mortality rate after both elective EVAR and OAR. By comparison, while the lowest BMI cohort was significantly associated with decreased long term survival after both procedures, the highest BMI group only experienced reduced long term survival after OAR. Based upon this large real world registry analysis of elective AAA repairs, differential metabolic signatures exist within extreme BMI categories, which may inform peri-operative risk stratification and clinical decision making.

A Non-Invasive Investigation into the Prevalence of Higher than Normal Blood Pressure, Hypertension and the Association between Blood Pressure and Body Weight in Male and Female Adolescents in the Polokwane Local Municipality, Limpopo-South Africa: A Cross-Sectional Study

BACKGROUND

Hypertension (HT) is one of the greatest non-communicable diseases affecting both sexes in all human populations; and it is a major cause of death and morbidity across the world. The purpose of this study was to investigate the prevalence of pre-hypertension, hypertension and investigate the association between blood pressure (BP) and body weight (looking into body mass index (BMI) and body surface area (BSA)).

METHOD

A cross-sectional study of adolescents aged 13-19 years was conducted at three secondary schools consisting of 121 females and 97 males. Data on height; weight; and blood pressure was collected from all participants. BMI and BP percentiles were calculated for each participant.

RESULTS

The prevalence of pre-hypertension and hypertension in males was 28.9% and 10.3% compared to 25.6% and 7.4% in females. The prevalence of pre-hypertension and hypertension in adolescents who are overweight/obese was 7.3% and 2.7%. A weak positive association between BMI; systolic blood pressure (SBP) and diastolic blood pressure (DBP) was found (r = 0.254 and 0.216; p-value = 0.001) for the whole population. A significant, moderate correlation was found between BSA on SBP was found (r = 0.407, p-value = 0.001); and a significant, weak correlation between BSA and DBP was found (r = 0.183, p-value = 0.007. In conclusion, the prevalence of pre-hypertension and hypertension was higher in males as compared to females. Results highlight the need for screening for blood pressure and body weight in adolescents; especially in adolescents who were found to have pre-hypertension as they are at high risk of developing hypertension.

Body surface area: a novel predictor for conversion to thoracotomy in patients undergoing video-assisted thoracoscopic lung cancer lobectomy

BACKGROUND

The purpose of our study was to explore the value of body surface area (BSA) for predicting conversion to thoracotomy in patients undergoing video-assisted thoracoscopic (VATS) lobectomy for non-small cell lung cancer (NSCLC).

METHODS

We performed a monocentric retrospective analysis based on a prospectively-maintained dataset of consecutive patients between March 2014 and August 2015 at our unit. The median value of BSA was used as the cut-off. Patients with BSA > median value were classified as the "large" group, while those with BSA ≤ median value were classified as the "non-large" group. The conversion rate and post-VATS morbidity between these two groups were evaluated. Finally, a multivariate logistic-regression analysis was performed to identify the predictors for conversion to thoracotomy.

RESULTS

A total of 475 patients with a median BSA of 1.73 m² were enrolled. There were 16 patients converted to thoracotomy (ratio =3.4%). The overall morbidity rate was 28.4%. The "large" group (BSA >1.73 m²) included 236 patients, while the "non-large" group (BSA ≤1.72 m²) included the remaining 239 patients. The conversion (5.5% vs. 1.3%; P=0.010) in the "large" patients was significantly higher than that in the "non-large" patients. No difference was found in the overall morbidity rate between these two groups (32.2% vs. 24.7%; P=0.069). The multivariate logistic-regression analysis demonstrated that BSA >1.73 m² could be a strongly independent predictor for conversion to thoracotomy [odds ratio (OR): 7.17; P=0.028].

CONCLUSIONS

BSA is an excellent categorical predictor for conversion to thoracotomy in NSCLC patients undergoing VATS lobectomy. It may be considered when informing patients about intraoperative risks and selecting cases in the early learning curve of VATS techniques.

Impact of obesity on short- and long-term outcomes of laparoscopy assisted distal gastrectomy for gastric cancer

BACKGROUND

Laparoscopy assisted distal gastrectomy (LADG) for gastric cancer has been rapidly adopted for the treatment of both early and advanced gastric cancers which need lymph node dissection, but remains difficult procedure, especially in patients with obesity. We evaluated the impact of obesity on short- and long-term outcomes of LADG for gastric cancer.

METHODS

We retrospectively investigated 243 patients who underwent LADG for gastric cancer between January 2007 and December 2014. The patients were classified based on their body mass index (BMI) into the Obese (BMI ≥ 25) and Non-Obese (BMI < 25) Groups. Patient characteristics, clinicopathologic and operative findings, and short- and long-term outcomes were investigated and compared between the groups.

RESULTS

The groups did not differ in age, sex, American Society of Anesthesiologists score, the presence of comorbidities, or pathologic stage. Operative time (265 ± 46.6 vs. 244 ± 55.6 min; P = 0.007) and estimated blood loss (113 ± 101.4 vs. 66.5 ± 95.2 ml; P = 0.007) were greater in the Obese Group. Fewer lymph nodes were retrieved in the Obese Group (38 ± 23.7 vs. 47.5 ± 24.3; P = 0.004). No differences were evident in postoperative complication rate (20% vs. 17%; P = 0.688) or the duration of postoperative hospital stay (9 ± 8.5 vs. 9 ± 5.1 days; P = 0.283) between the two groups. In the Obese Group, the 5-year overall survival rate was significantly lower than in the Non-Obese Group (67.6% vs. 90.3%; P = 0.036). Furthermore, 5-year disease-specific survival was significantly lower in the Obese Group than in the Non-Obese Group (72.7% vs. 94.9%; P = 0.015).

CONCLUSIONS

LADG in patients with obesity could be performed as safe as in patients without obesity, with comparable postoperative results. But obesity may be a poor prognostic factor in gastric cancer.

Body surface area is a novel predictor for surgical complications following video-assisted thoracoscopic surgery for lung adenocarcinoma: a retrospective cohort study

Background

Body surface area (BSA) is a biometric unit to measure the body size. Its clinical significance in video-assisted thoracoscopic surgery (VATS) was rarely understood. We aimed to estimate the predictive value of BSA for surgical complications following VATS anatomical resections for lung adenocarcinoma (LAC).

Methods

A single-center retrospective analysis was performed on the consecutive patients between July 2014 and January 2016 in our institution. The differences in mean BSA values were evaluated between groups of patients classified by the development of postoperative surgical complications (PSCs), overall morbidity and cardiopulmonary complications, respectively. Receiver operating characteristic (ROC) analysis was performed to determine a threshold value of BSA on prediction of PSC occurrence. A multivariate logistic-regression model involving this optimal cut-off value and other significant parameters was established to identify the predictors for PSCs.

Results

During the study period, a total of 442 patients undergoing VATS anatomical resections for LAC were enrolled in this study. There were 135 patients developed with one or more complications (rate = 30.5%). PSCs occupied the largest percentages of all these complications (n = 81, rate = 18.3%). The mean BSA in PSC group was significantly higher than that in non-PSC group (1.76 ± 0.15 m² vs 1.71 ± 0.16 m²; P = 0.016). No difference was found in mean BSA values between groups classified by any other complication. The ROC analysis determined a BSA value of 1.68 m² to be the threshold value with the maximum joint sensitivity of 72.8% and specificity of 48.5%. Compared to patients with BSA ≤ 1.68 m², patients with BSA > 1.68 m² had significantly higher incidences of prolonged air leak (P = 0.006) and chylothorax (P = 0.004). Further multivariate logistic-regression analysis indicated that BSA > 1.68 m² could be an independent risk factor for PSCs (odds ratio: 2.03; P = 0.025).

Conclusions

BSA is an excellent categorical predictor for surgical complications following VATS anatomical resections for LAC. It may be considered when informing patients about surgical risks and selecting cases in the early learning curve. Large-scale and multi-institutional studies are expected to confirm and modify our findings in the future.

Electronic supplementary material

The online version of this article (doi:10.1186/s12893-017-0264-4) contains supplementary material, which is available to authorized users.

Right versus left laparoscopic colectomy for colon cancer: does side make any difference?

PURPOSE

To compare the intraoperative and postoperative outcomes between right laparoscopic colectomy (RLC) and left laparoscopic colectomy (LLC) for colon cancer.

METHOD

Patients who underwent elective RLC or LLC for colon cancer between January 2004 and December 2014 were identified and elected for a retrospective analysis. Primary outcomes were technical difficulty (including operative time, intraoperative complications, and conversion rate) and postoperative outcome (including postoperative complications, length of hospital stay, reinterventions, readmissions, and mortality).

RESULTS

A total of 547 patients (mean age: 68.5 years old; 48.4% males) were analyzed. The RLC group had a higher mean age (71 vs 65; p < 0.001), ASA 3/4 grade (36 vs 26%; p = 0.02), and comorbidity rate (61 vs 48%, p = 0.003). Regarding technical difficulty, no difference was found between the groups in intraoperative complications (4.1 vs 5.9%; p = 0.34) or conversion rate (6.2 vs 3.9%, p = 0.24). Mean operative time was significantly shorter for RLC (162 vs 185 min, p < 0.001). Regarding postoperative outcome, the RLC group had a higher overall morbidity (20.5 vs 13.3%, p = 0.03), ileus (10.6 vs 2.4%, p < 0.001), and a longer hospital stay (4.7 vs 3.9 days, p = 0.003), with no differences regarding reoperations, readmissions, or mortality. The multivariate analysis showed that RLC were independently associated with a longer operative time and postoperative ileus.

CONCLUSIONS

RLC for colon cancer was independently associated with a shorter operative time, an increased risk of ileus, and a longer hospital stay than left laparoscopic colectomy in high-volume centers.

Obesity Increases Operative Time in Children Undergoing Laparoscopic Cholecystectomy

INTRODUCTION

Few studies have assessed the impact of obesity on laparoscopic cholecystectomy (LC) in pediatric patients.

MATERIALS AND METHODS

Children who underwent LC were identified from the 2012 to 2013 American College of Surgeons' National Surgical Quality Improvement Program Pediatrics data. Patient characteristics, operative details, and outcomes were compared. Multivariable logistic regression was utilized to identify predictors of increased operative time (OT) and duration of anesthesia (DOAn).

RESULTS

In total, 1757 patients were identified. Due to low rates of obesity in children <9 years old, analyses were limited to those 9-17 (n = 1611, 43% obese). Among obese children, 80.6% were girls. A higher proportion of obese patients had diabetes (3.0% versus 1.0%, P < .01) and contaminated or dirty/infected wounds (15.1% versus 9.4%, P < .01). Complication rates were low. The most frequent indications for surgery were cholelithiasis/biliary colic (34.3%), chronic cholecystitis (26.9%), and biliary dyskinesia (18.2%). On multivariable analysis, obesity was an independent predictor of OT >90 (odds ratio [OR] 2.02; 95% confidence interval [95% CI] 1.55-2.63), and DOAn >140 minutes (OR 1.86; 95% CI 1.42-2.43).

CONCLUSIONS

Obesity is an independent risk factor for increased OT in children undergoing LC. Pediatric surgeons and anesthesiologists should be prepared for the technical and physiological challenges that obesity may pose in this patient population.

Influence of body habitus on the surgical outcomes of bilateral axillo-breast approach robotic thyroidectomy in papillary thyroid carcinoma patients

Purpose

Obesity is associated with a number of medical comorbidities and is considered a risk factor for surgical complications. The purpose of this study was to analyze the influence of body habitus including obesity on the surgical outcomes of the Bilateral axillo-breast approach (BABA) robotic thyroidectomy (RoT) in papillary thyroid carcinoma (PTC) patients.

Methods

The medical records of 456 PTC patients who underwent BABA RoT between January 2011 and December 2012 were reviewed, and 310 women PTC patients who had undergone BABA robotic total thyroidectomy with central lymph node dissection were examined. Body habitus were evaluated by measuring body mass index (BMI), body surface area, and neck circumference. We divided the patients into BMI < 25 kg/m² and BMI ≥ 25 kg/m² groups. Clinicopathological data, surgical outcomes, and postoperative complications were evaluated.

Results

Clinicopathological characteristics did not differ between the 2 BMI groups. The creation of working space time (P = 0.210) and other surgical outcomes showed no significant differences between the groups. There were no statistically significant differences between body habitus indexes and postoperative length of hospital stay, number of retrieved central lymph nodes, postoperative thyroglobulin levels, occurrence of hypoparathyoidism, recurrent laryngeal nerve injury and wound complication.

Conclusion

Patient with large body habitus undergoing BABA RoT were not at an increased risk of surgical complications and showed good surgical outcomes. BABA RoT may be a good alternative operative method for PTC patients for whom cosmetic outcome is an important consideration.

Effect of small body habitus on peri-operative outcomes after robotic-assisted pulmonary lobectomy: retrospective analysis of 208 consecutive cases

BACKGROUND

Patients with smaller body surface area (BSA) have smaller pleural cavities, which limit visualization and instrument mobility during video-assisted thoracoscopic surgery (VATS). We investigated the effects of BSA on outcomes with robotic-assisted VATS lobectomy.

METHODS

We analyzed 208 consecutive patients who underwent robotic-assisted lobectomy over 34 months. Patients were separated into group A (BSA ≤1.65 m(2)) and group B (BSA >1.65 m(2)). Operative times, estimated blood loss (EBL), conversions to thoracotomy, complications, hospital length of stay (LOS), and in-hospital mortality were compared.

RESULTS

Group A had 40 patients (BSA 1.25-1.65 m(2)), and group B had 168 patients (BSA 1.66-2.86 m(2)). Median skin-to-skin operative times [± standard error of the mean (SEM)] were 169±16 min for group A and 176±6 min for group B (P=0.34). Group A had median EBL of 150±96 mL compared to 200±24 mL for group B (P=0.37). Overall conversion rate to thoracotomy was 8/40 (20.0%) in group A versus 12/168 (7.1%) in group B (P=0.03); while emergent conversion for bleeding was 2/40 (5.0%) in group A versus 5/168 (3.0%) in group B (P=0.62). Postoperative complications occurred in 12/40 (30.0%) in group A, compared to 66/168 (39.3%) in group B (P=0.28). Patients from both groups had median hospital LOS of 5 days (P=0.68) and had similar in-hospital mortality.

CONCLUSIONS

Patients with BSA ≤1.65 m(2) have similar perioperative outcomes and complication risks as patients with larger BSA. Patients with BSA ≤1.65 m(2) have a higher overall conversion rate to thoracotomy, but similar conversion rate for bleeding as patients with larger BSA. Robotic-assisted pulmonary lobectomy is feasible and safe in patients with small body habitus.

Comparison of Risk Factors for Unplanned Conversion from Laparoscopic and Robotic to Open Colorectal Surgery Using the Michigan Surgical Quality Collaborative (MSQC) Database

Robotic colorectal surgery has been shown to have lower rates of unplanned conversion to open surgery when compared to laparoscopic surgery. Risk factors associated with conversion from robotic to open colectomy and comparisons of the risk factors between robotic and laparoscopic approaches have not been previously reported. Patients who underwent elective laparoscopic and robotic colorectal surgeries between July 1, 2012 and April 28, 2015, were identified in the Michigan Surgical Quality Collaborative registry. Candidate covariates were identified, and hierarchical logistic regression models were used to identify risk factors for conversion. There were 4796 cases that met study inclusion criteria. Conversion was required in 18.2 % of laparoscopic and 7.7 % of robotic cases (p < 0.0001). Risk factors for conversion in the laparoscopic group included the following: moderate/severe adhesions, obesity, colorectal cancer, hypertension, rectal operations, urgent priority, and tobacco use. Risk factors for conversion in the robotic group included the following: severe adhesions, bleeding disorder, presence of cancer, cirrhosis, and use of statins. Higher surgeon volume was protective in both groups. Conversion rates are lower for robotic than for laparoscopic colorectal surgery with fewer predictors of conversion. Recognition of factors predicting conversion may allow surgeons to choose an operative approach that optimizes the benefits of the available technologies.

Body Surface Area: A new predictive factor of mortality and pancreatic fistula after pancreaticoduodenectomy: A cohort-study

INTRODUCTION

To assess the role of Body Surface Area (BSA) in predicting pancreatic fistula and mortality after pancreaticoduodenectomy.

METHODS

The data of patients who underwent pancreaticoduodenectomy between January 1992 to December 2012 at the University Hospital of Caen were collected prospectively and analyzed retrospectively. Pancreatic fistula was determined according to the ISPGF (International Study Group for Pancreatic Fistula) criteria. The Clavien and Dindo classification was used for grading post-operative complications and BSA was calculated according to the Boyd formula. Patients were classified as "large" and "non-large" using a BSA value ≥1.82 to define the large group and the non-large group. The primary end points were post-operative mortality rate, and the rate and grade of post-operative pancreatic fistula.

RESULTS

411 patients underwent pancreaticoduodenectomy with a mean age of 61.2 (±12.1) year. Six patients (1.45%) died post-operatively. Patients with a BSA ≥1.82 had a significantly higher risk of post-operative death: OR 3.55 [1.43-8.80] (p < 0.0005). Eighty-five patients (20.7%) developed a post-operative pancreatic fistulas. The grade A pancreatic fistula rate was 87.1%. Patients with a BSA ≥1.82 had a significantly higher risk of developing overall post-operative pancreatic fistula (p < 0.038). Multivariate analysis showed that "large" patients (1.86, 95%CI[1.09-3.92], p = 0.0229), soft pancreas (6.5, 95%CI[2.39-9.31], p = 0.0155) and a BMI ≥ 25 (1.09, 95%CI[1.031-1.163], p = 0.0407) were independent risk factors of pancreatic fistula.

CONCLUSION

Body Surface Area is a useful factor after pancreaticoduodenectomy to predict mortality and post-operative fistula.

Factors associated with conversion from laparoscopic to open colectomy using the National Surgical Quality Improvement Program (NSQIP) database

AIM

Conversion rates from laparoscopic to open colectomy and associated factors are traditionally reported in clinical trials or reviews of outcomes from experienced institutions. Indications and selection criteria for laparoscopic colectomy may be more narrowly defined in these circumstances. With the increased adoption of laparoscopy, conversion rates using national data need to be closely examined. The purpose of this study was to use data from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) to identify factors associated with conversion of laparoscopic to open colectomy at a national scale in the United States.

METHOD

The ACS-NSQIP Participant Use Data Files for 2006-2011 were used to identify patients who had undergone laparoscopic colectomy. Converted cases were identified using open colectomy as the primary procedure and laparoscopic colectomy as 'other procedure'. Preoperative variables were identified and statistics were calculated using sas version 9.3. Logistic regression was used to model the multivariate relationship between patient variables and conversion status.

RESULTS

Laparoscopy was successfully performed in 41 585 patients, of whom 2508 (5.8%) required conversion to an open procedure. On univariate analysis the following factors were significant: age, body mass index (BMI), American Society of Anesthesiologists (ASA) class, presence of diabetes, smoking, chronic obstructive pulmonary disease, ascites, stroke, weight loss and chemotherapy (P < 0.05). The following factors remained significant on multivariate analysis: age, BMI, ASA class, smoking, ascites and weight loss.

CONCLUSION

Multiple significant factors for conversion from laparoscopic to open colectomy were identified. A novel finding was the increased risk of conversion for underweight patients. As laparoscopic colectomy is become increasingly utilized, factors predictive of conversion to open procedures should be sought via large national cohorts.

Laparoscopic colorectal resections: a simple predictor model and a stratification risk for conversion to open surgery

BACKGROUND

The advantages associated with the laparoscopic approach are lost when conversion is required. Available predictive models have failed to show external validation. Body surface area is a recently described risk factor not included in these models.

OBJECTIVE

The aim of this study was to develop a clinical rule including body surface area for predicting conversion in patients undergoing elective laparoscopic colorectal surgery.

DESIGN

This was a prospective cohort study.

SETTING

This study was conducted at a single large tertiary care institution.

PATIENTS

Nine hundred sixteen patients (mean age, 63.9; range, 14-91 years; 53.2% female) who underwent surgery between January 2004 and August 2011 were identified from a prospective database.

MAIN OUTCOME MEASURES

Conversion rate was analyzed related to age, sex, obesity, disease location (colon vs rectum), type of disease (neoplastic vs nonneoplastic), history of previous surgery, and body surface area. A predictive model for conversion was developed with the use of logistic regression to identify independently associated variables, and a simple clinical prediction rule was derived. Internal validation of the model was performed by using bootstrapping.

RESULTS

The conversion rate was 9.9% (91/916). Rectal disease, large patient size, and male sex were independently associated with higher odds of conversion (OR, 2.28 95%CI, 1.47-3.46]), 1.88 [1.1-3.44], and 1.87 [1.04-3.24]). The prediction rule identified 3 risk groups: low risk (women and nonlarge males), average risk (large males with colon disease), and high risk (large males with rectal disease). Conversion rates among these groups were 5.7%, 11.3%, and 27.8% (p < 0.001). Compared with the low-risk group, ORs for average- and high-risk groups were 2.17 (1.30-3.62, p = 0.004) and 6.38 (3.57-11.4, p < 0.0001).

LIMITATIONS

The study was limited by the lack of external validation.

CONCLUSION

This predictive model, including body surface area, stratifies patients with different conversion risks and may help to inform patients, to select cases in the early learning curve, and to evaluate the standard of care. However, this prediction rule needs to be externally validated in other samples (see Video, Supplemental Digital Content 1, http://links.lww.com/DCR/A137).

Waist circumference and waist/hip ratio are better predictive risk factors for mortality and morbidity after colorectal surgery than body mass index and body surface area

OBJECTIVES

To determine whether body fat distribution, measured by waist circumference (WC) and waist/hip ratio (WHR), is a better predictor of mortality and morbidity after colorectal surgery than body mass index (BMI) or body surface area (BSA).

BACKGROUND

Obesity measured by BMI is not a consistent risk factor for postoperative mortality and morbidity after abdominal surgery. Studies in metabolic and cardiovascular diseases have shown WC and WHR to be better outcome predictors than BMI.

METHODS

A prospective multicenter international study was conducted among patients undergoing elective colorectal surgery. The WHR, BMI, and BSA were derived from body weight, height, and waist and hip circumferences measured preoperatively. Uni- and multivariate analyses were performed to identify risk factors for postoperative outcomes.

RESULTS

A total of 1349 patients (754 men) from 38 centers in 11 countries were included. Increasing WHR significantly increased the risk of conversion [odds ratio (OR) = 15.7, relative risk (RR) = 4.1], intraoperative complications (OR = 11.0, RR = 3.2), postoperative surgical complications (OR = 7.7, RR = 2.0), medical complications (OR = 13.2, RR = 2.5), anastomotic leak (OR = 13.7, RR = 3.3), reoperations (OR = 13.3, RR = 2.9), and death (OR = 653.1, RR = 21.8). Both BMI (OR = 39.5, RR = 1.1) and BSA (OR = 4.9, RR = 3.1) were associated with an increased risk of abdominal wound complication. In multivariate analysis, the WHR predicted intraoperative complications, conversion, medical complications, and reinterventions, whereas BMI was a risk factor only for abdominal wall complications; BSA did not reach significance for any outcome.

CONCLUSIONS

The WHR is predictive of adverse events after elective colorectal surgery. It should be used in routine clinical practice and in future risk-estimating systems.