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. Ann Surg. 2013;258:722-730. [PMID: 24096768 DOI: 10.1097/sla.0b013e3182a6605a]

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.

Day-surgery adult patients with obesity and obstructive sleep apnea: Current controversies and concerns

Obesity and obstructive sleep apnea are considered independent risk factors that can adversely affect perioperative outcomes. A combination of these two conditions in the ambulatory surgery patient can pose significant challenges for the anesthesiologist. Nevertheless, these patients should not routinely be denied access to ambulatory surgery. Instead, patients should be appropriately optimized. Anesthesiologists and surgeons must work together to implement fast-track anesthetic and surgical techniques that will ensure successful ambulatory outcomes.

Visceral obesity and anastomotic leakage rates in colorectal cancer: a systematic review and meta-analysis

Background

Numberous studies have heatedly discussed whether obesity is a risk factor for anastomotic leakage (AL) because of the increasing number of colorectal cancer (CRC) cases and high incidence of CRC in patients with obesity.

Objective

We aimed to explore the relationship between visceral obesity(VO) and AL after CRC surgery. The databases of Pubmed, Embase, and the Cochrane Library were searched for relevant data and articles published until November 1, 2022. We identified the difference in the incidence of AL after CRC surgery between patients with and without VO. The quality of included studies was evaluated using the Newcastle- Ottawa Scale, and odds ratio (OR) and 95% CI were used to assess the association between VO and AL.

Results

This meta-analysis included 7 studies with 2,136 patients. The OR of patients with VO versus those without VO was 2.15 (95%CIs = 1.46-3.15, test for heterogeneity: P = 0.29, I2 = 18%) based on the fixed-effect model in seven studies. Notably, the difference between the two groups was statistically significant (Z = 3.91 P < 0.0001). Patients with VO in the colon cancer group exhibited a higher incidence of AL (OR = 2.88, 95% CIs = 1.38-5.99, test for heterogeneity: P = 0.27, I2 = 20%) than those in the rectal cancer group (OR = 2.74, 95% CIs = 1.13-6.65, test for heterogeneity: P = 0.20, I2 = 38%). In the studies in the relevant literature, heterogeneity was low. Regarding patients with VO, four Asian studies reported increased morbidity due to AL (OR = 2.79, 95% CIs = 1.35-5.78, test for heterogeneity: P = 0.35, I2 = 9%) compared with three non-Asian studies.

Conclusions

Our findings confirmed the significant relationship between VO and AL. Thus, VO could be considered a reliable risk factor of surgery for colon cancer.

Does the visceral fat area impact the histopathology specimen metrics after total mesorectal excision for distal rectal cancer?

BACKGROUND

The aim of this study was to evaluate whether the visceral fat area (VFA) has an impact on the histopathology specimen metrics of male patients undergoing robotic total mesorectal resection (rTME) for distal rectal cancer.

METHODS

Prospectively collected data of patients undergoing rTME for resectable rectal cancer by five surgeons during a period of three years were extracted from the REgistry of Robotic SURgery for RECTal cancer (RESURRECT). VFA was measured in all patients at preoperative computed tomography. Distal rectal cancer was defined as <6cm from the anal verge. The histopathology metrics included circumferential resection margin (CRM) (in mm) and its involvement rate (if <1mm), distal resection margin (DRM), and quality of TME (complete, nearly-complete, incomplete).

RESULTS

Of 839 patients who underwent rTME, 500 with distal rectal cancer were included. One hundred and six (21.2%) males with VFA>100cm² were compared to 394 (78.8%) males or females with VFA≤100cm². The mean CRM of males with VFA>100cm² was not significantly different from its counterpart (6.6 ± 4.8 mm versus 7.1 ± 9.5mm; p=0.752). CRM involvement rates were 7.6% in both groups (p=1.000). The DRM was not significantly different: 1.8±1.9cm versus 1.8±2.6cm; p=0.996. The quality of TME did not significantly differ: complete TME 87.3% vs. 83.7%; nearly complete TME 8.9% vs. 12.8%; incomplete TME 3.8% vs. 3.6%. Complications and clinical outcomes did not significantly differ.

CONCLUSION

This study did not find evidence to support that increased VFA would result in suboptimal histopathology specimen metrics when performing rTME in males with distal rectal cancer.

Does the mesorectal fat area impact the histopathology metrics of the specimen in males undergoing TME for distal rectal cancer?

The aim of this study was to evaluate whether the mesorectal fat area (MFA) has an impact on the histopathology metrics of the specimen in male patients undergoing robotic total mesorectal excision (rTME) for cancer in the distal third of the rectum. Prospectively collected data of patients undergoing rTME for resectable rectal cancer by five surgeons during 3 years were extracted from the REgistry of Robotic SURgery for RECTal cancer (RESURRECT). MFA was measured at preoperative MRI. Distal rectal cancer was defined as within 6 cm from the anal verge. Specimen metrics included circumferential resection margin (CRM) measured by pathologists as involved if < 1 mm, distal resection margin (DRM) and TME quality. Of 890 patients who underwent rTME for rectal cancer, a subgroup analysis compared 116/581 (33.4%) with MFA > 20 cm² to 231/581 (66.6%) with MFA ≤ 20 cm². The mean CRM in patients with MFA > 20 cm² was neither statistically nor clinically significantly different from patients with MFA ≤ 20 m² (6.8 ± 5.6 mm vs. 6.0 ± 7.5 mm; p = 0.544). The quality of TME did not significantly differ: complete TME 84.3% vs. 80.3%; nearly complete TME 12.9% vs. 10.1%; incomplete TME 6.8% vs. 5.6%. The DRM was not significantly different: 1.9 ± 1.9 cm vs. 1.9 ± 2.5 cm; p = 0.847. In addition, the intraoperative complication rate was not significantly different: 4.3% (n = 5) vs. 2.2% (n = 5) (p = 0.314). This prospective multicenter study did not find any evidence to support that larger MFA would result in poorer histopathology metrics of the specimen when performing rTME in male patients with distal rectal cancer.

Does the mesorectal fat area impact the histopathology metrics of the specimen in males undergoing TME for distal rectal cancer?

The aim of this study was to evaluate whether the mesorectal fat area (MFA) has an impact on the histopathology metrics of the specimen in male patients undergoing robotic total mesorectal excision (rTME) for cancer in the distal third of the rectum. Prospectively collected data of patients undergoing rTME for resectable rectal cancer by five surgeons during 3 years were extracted from the REgistry of Robotic SURgery for RECTal cancer (RESURRECT). MFA was measured at preoperative MRI. Distal rectal cancer was defined as within 6 cm from the anal verge. Specimen metrics included circumferential resection margin (CRM) measured by pathologists as involved if < 1 mm, distal resection margin (DRM) and TME quality. Of 890 patients who underwent rTME for rectal cancer, a subgroup analysis compared 116/581 (33.4%) with MFA > 20 cm² to 231/581 (66.6%) with MFA ≤ 20 cm². The mean CRM in patients with MFA > 20 cm² was neither statistically nor clinically significantly different from patients with MFA ≤ 20 m² (6.8 ± 5.6 mm vs. 6.0 ± 7.5 mm; p = 0.544). The quality of TME did not significantly differ: complete TME 84.3% vs. 80.3%; nearly complete TME 12.9% vs. 10.1%; incomplete TME 6.8% vs. 5.6%. The DRM was not significantly different: 1.9 ± 1.9 cm vs. 1.9 ± 2.5 cm; p = 0.847. In addition, the intraoperative complication rate was not significantly different: 4.3% (n = 5) vs. 2.2% (n = 5) (p = 0.314). This prospective multicenter study did not find any evidence to support that larger MFA would result in poorer histopathology metrics of the specimen when performing rTME in male patients with distal rectal cancer.

Obesity paradox among patients undergoing total knee arthroplasty: a retrospective cohort study

BACKGROUND

Obesity has been recognized as the risk factor for postoperative complication for surgical patients. However, recent studies have showed protective effect of obesity in surgical and non-surgical patients. Our study is to examine the association of body mass index(BMI) with early postoperative complications in patients undergoing total knee arthroplasty.

MATERIALS AND METHODS

All patients who had primary total knee arthroplasty between January 2014 and December 2019 were included. Medical records were retrospectively reviewed and BMI was categorized as underweight(BMI < 18.5), normal weight(18.5 < BMI < 24.9), overweight I(25 < BMI < 27.4), overweight II(27.5 < BMI < 29.9), obese I(30 < BMI < 34.9) and obese II(BMI ≥ 35). The association between BMI and occurrence of early postoperative complications was examined and logistic regression was used to calculate relationship between BMI and early postoperative complications.

RESULTS

A total of 2969 patients were included in our analysis. The overall complication rate in patients undergoing total knee arthroplasty was 14.8%, with the highest complication being 22.2% in the underweight group, the second highest in the normal weight group(17.5%), the lowest in the overweight I(13.8%) and obese I(12.0%) group and then higher again in obese II group(16.7%). In multivariable analyses, overweight I (OR 0.737, 95% CI 0.559-0.972, P = 0.031) and obese I (OR 0.631, 95% CI 0.449-0.885, P = 0.008) were associated with lower risk of early postoperative complications after total knee arthroplasty.

CONCLUSION

In this retrospective study, overweight and obese patients had a lower risk of early postoperative complications after total knee arthroplasty. Further studies are necessary to confirm and investigate the mechanism of obesity paradox in this surgical population.

TRIAL REGISTRATION

This study had been registrated in www.chictr.org.cn on 25/10/2021 and the registration ID was ChiCTR2100052408.

Risk factors for leak after omentopexy for duodenal ulcer perforations

AIMS

Duodenal ulcer perforations are frequently encountered but there is limited literature regarding risk factors for leak after omentopexy.

METHODOLOGY

The record of 100 patients of duodenal ulcer perforation undergoing omentopexy by open approach was prospectively maintained to identify any significant factors contributing towards leak.

RESULTS

Out of 100 patients undergoing omentopexy, 9 (9%) developed leak; when leak occurred, the mortality was very high (44.4%). Patients who developed leak (09) were compared against those who did not (91), and it was seen that seen that duration of symptoms before surgery (> 3 days), amount of intra-abdominal contamination (> 2 L), low body mass index (BMI < 19.35 kg/m²), serum creatinine (> 1.5 mg/dl), and deranged International Normalized Ratio (INR) were found to be significant on univariate analysis; however, multivariate analysis revealed only low BMI and high creatinine to be contributory towards leak.

CONCLUSION

Leak after omentopexy carries a high morbidity and mortality. Identification of risk factors may help in optimizing patients at risk and reduce the incidence of leak and its sequelae.

TRIAL REGISTRATION NUMBER

CTRI/2020/03/023798.

Predicting recovery and disability after surgery in patients with severe obesity: The role of the six-minute walk test

The most appropriate method to predict postoperative outcomes in patients with severe obesity undergoing elective non-bariatric surgery is not known. We conducted a single-centre prospective cohort study in patients with a body mass index of at least 35 kg/m² undergoing non-bariatric, non-cardiac surgery. Patients completed the six-minute walk test prior to surgery. Disability was measured before and six months after surgery using the World Health Organization disability assessment schedule. Primary outcome measures included quality of recovery at one month and significantly increased disability at six months after surgery. A total of 293 patients participated. The median body mass index was 41 kg/m². Patients generally recovered well. Following surgery, 9% of patients experienced a poor quality of recovery and 7% developed a significant increase in disability. The proportion of patients free from clinically significant disability increased from 66% prior to surgery to 90% at six months after surgery. The distance walked in six minutes was weakly predictive of poor recovery at one month and significantly increased disability at six months; weight and body mass index were not. The area under the receiver operating characteristic curve was 0.65 (95% confidence intervals 0.51 to 0.78) for poor recovery and 0.64 (95% confidence intervals 0.51 to 0.77) for increased disability. A preoperative six-minute walk test distance of 308 m was the best cut-off value for predicting increased postoperative disability (sensitivity 0.68, specificity 0.63). The six-minute walk test was most discriminatory at shorter distances. This population of patients with severe obesity appeared to recover well and had few adverse outcomes. The degree of functional capacity was more important than the degree of obesity in predicting postoperative outcomes.

New Measures, Old Conclusions: Obesity Does Not Worsen Outcomes after Elective Abdominal Aortic Aneurysm Repair

Background  The “obesity paradox,” whereby the body mass index (BMI) mortality curve is “U-shaped,” is a well-studied phenomenon in vascular surgery. However, there has been an overreliance on BMI as the measure of obesity, which has shown to poorly correlate with clinical outcomes. Robust measures such as waist-hip ratio (WHR) have been suggested as a more accurate marker reflecting central obesity.

Objectives  The objectives of this study were to evaluate the correlation between BMI and WHR on postoperative morbidity and mortality after elective abdominal aortic aneurysm (AAA) repair.

Methods  Data were collected from the Leeds Vascular Institute between January 2006 and December 2016. The primary outcome was mortality and secondary outcomes included length of stay (LOS) and all-cause readmission. Binary logistic regression, linear regression, and correlation analysis were used to identify associations between BMI and WHR in relation to outcome measures.

Results  After exclusions, 432 elective AAA repairs (281 open surgical repair [OSR] and 151 endovascular aneurysm repairs [EVARs]) were identified to be eligible for the study. The combined 30-day and 4-year mortality was 1.2 and 20.1%, respectively. The 30-day readmission rate was 3.9% and the average LOS was 7.33 (standard deviation 18.5) days. BMI data was recorded for 275 patients (63.7%) and WHR for 355 patients (82.2%). Logistic regression analysis highlighted no association between BMI and WHR with mortality, readmission, or LOS following OSR or EVAR.

Conclusion  The results of this study suggest patients should not be denied treatment for AAA based on obesity alone.

Patient Selection for Adult Ambulatory Surgery: A Narrative Review

With migration of medically complex patients undergoing more extensive surgical procedures to the ambulatory setting, selecting the appropriate patient is vital. Patient selection can impact patient safety, efficiency, and reportable outcomes at ambulatory surgery centers (ASCs). Identifying suitability for ambulatory surgery is a dynamic process that depends on a complex interplay between the surgical procedure, patient characteristics, and the expected anesthetic technique (eg, sedation/analgesia, local/regional anesthesia, or general anesthesia). In addition, the type of ambulatory setting (ie, short-stay facilities, hospital-based ambulatory center, freestanding ambulatory center, and office-based surgery) and social factors, such as availability of a responsible individual to take care of the patient at home, can also influence patient selection. The purpose of this review is to present current best evidence that would provide guidance to the ambulatory anesthesiologist in making an informed decision regarding patient selection for surgical procedures in freestanding ambulatory facilities.

Preoperative white blood cell count predicts anastomotic leakage in patients with left-sided colorectal cancer

To determine whether preoperative white blood cell (WBC) counts reflect risk of anastomotic leak (AL) for patients with colorectal cancer (CRC), we retrospectively examined data from records of 208 consecutive patients who had undergone resections for left-sided CRC, including their clinicopathological parameters and preoperative laboratory data. The diagnostic value of WBC count for AL was evaluated and compared with those of neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, lymphocyte-monocyte ratio and platelet count × C-reactive protein level multiplier (P-CRP) value; optimal cut-off values were derived from receiver operating characteristic curves. AL was observed in 11 of the 208 patients (5.3%). Compared with the no-AL group, the AL group had a significantly higher mean WBC count and smoking rate. In multivariate analysis, WBC count and smoking were independent risk factors for AL. Compared with the other tested inflammatory indicators, the cut-off value for WBC (6,200/μL) had the highest sensitivity (81.8%) and negative predictive value (98.4%), as well as the lowest likelihood ratio (0.289). Preoperative WBC count could therefore be a convenient predictor of AL in patients with left-sided CRC.

TIMING OPTIMIZATION OF HEAD AND NECK CT ANGIOGRAPHY VIA THE INVERSE PROBLEM ALGORITHM: in vivo SURVEY FOR 1001 PATIENTS IN 2020–2021

This study processed the recent in vivo survey results for over a thousand patients and optimized their neck and head CT angiography triggered timing (CTA-TT) via the inverse problem algorithm, which ensured the maximal ratio of both left and right arterial to upper sinuses (LRA/US). These results are instrumental in examining the ischemic stroke syndromes along the neck and head. These 1001 patients were randomly categorized into test surveyed (802 patients) and verification group (199 patients), then a six factors semi-empirical formula was constructed by the STATISTICA program. The six factors were assigned a patient’s biological data and preset of the CTA facility; namely Age, mean arterial pressure (MAP), heart rate (HR), contrast media dose (CMD), Pre (injected pressure of CMD), and body surface area (BSA). Each factor was normalized into dimensionless values and incorporated into the dataset matrix [Formula: see text] to analyze the coefficient matrix [Formula: see text]. The derived semi-empirical formula closely correlated with experimental data, according to the loss function [Formula: see text], correlation coefficient [Formula: see text], and variance of 0.8965. The formula verification for 199 more patients (verification group) yielded a correlation coefficient [Formula: see text]. Thus, it can be used for the CTA-TT estimation of patients without their preliminary tests, avoiding unnecessary irradiation. The estimated LRA/US was [Formula: see text] for the verification group in this study. A simplified three-factor formula, featuring only age, MAP, and BSA, was also proposed.

The abdominal waist circumference and 4-year outcomes following peripheral bypass grafting

BACKGROUND

Current literature evaluating the relationship between obesity, utilizing measures other than the Body Mass Index (BMI), and postoperative outcomes following vascular surgery are sparse. This study aimed to investigate any association between abdominal waist circumference (AWC) and waist-hip ratio (WHR) in relation to postoperative morbidity and mortality following peripheral artery bypass graft (PABG) surgery.

METHODS

AWC and hip circumference (HC) were measured from pre-intervention magnetic resonance (MR) and computed tomography (CT) scans of patients undergoing elective and nonelective PABG. The AWC and WHR were assessed in relation to: the need for higher level care (i.e. level 2/3), the duration of higher level care, postoperative limb ischemia, postoperative hospital stay, graft patency on discharge and 30 day readmission, using logistic and linear regression analysis. Mortality was assessed using cox-regression analysis with calculation of hazard ratios at 30 days and 4 years.

RESULTS

In total, 177 patient images performed between January 2014 to January 2017 were analyzed. There were no significant intra-observer and interobserver differences in measurements of AWC and HC. Pre-intervention AWC was predictive of the need for higher level care following non-elective PABG (adjusted OR 1.1 [95% CI: 1.0-1.1, P=0.026]). An inverse relationship between AWC and mortality at 4 years was also observed (adjusted HR=0.9, 95% CI: 0.9-1.0, P=0.028). However, pre-intervention WHR failed to predict mortality and morbidity.

CONCLUSIONS

AWC may potentially be a suitable risk stratification tool in patients undergoing non-elective PABG. The association of AWC with long-term mortality outcomes require further investigation so that suitable cut-off values may be determined.

Computed Tomography Assessment of Fat Distribution and Staple-Line Leak Risk After Sleeve Gastrectomy

PURPOSE

Sleeve gastrectomy (SG) has become the most frequent bariatric procedure and staple-line leak represents its most feared complication. Visceral obesity, a core component of the metabolic syndrome, has been associated with worst postoperative outcomes after various abdominal surgical procedures, and can be estimated by computed tomography (CT). The aim of this study was to assess the impact of radiologically determined visceral obesity in the risk of staple-line leak after SG.

MATERIAL AND METHODS

A retrospective analysis of a prospective database was performed in consecutive patients undergoing SG. Several anthropometric variables were measured on a preoperative CT scan. Multivariate analysis was performed to determine preoperative risk factors for staple-line leak.

RESULTS

During the study period, 377 patients were included in the analysis. The median BMI was 39.7 kg/m² (36.5-43.5) and 8 patients (2.1%) presented a gastric leak. After multivariate analysis, visceral obesity defined by visceral fat area (VFA)/body surface area (BSA) ≥ 85 cm²/m² was the only independent predictive factor for gastric leak (OR = 5312).

CONCLUSION

CT scan-assessed visceral obesity defined by a VFA/BSA ratio ≥ 85 cm²/m² is associated with an increased risk of gastric leak after SG. Preoperatively radiological examination in patients suspected of visceral obesity would be useful to optimize preoperative management.

Abdominal Wall Thickness is a Predictor for Surgical Site Infections in Patients Undergoing Colorectal Operations

BACKGROUND

Surgical site infections (SSIs) are an established complication following colorectal operations, with rates up to 30% reported in the literature. Obesity is a known risk factor for SSI; however, body mass index (BMI), body fat percentage, waist-hip ratio, or abdominal circumference are imperfect measures. The purpose of our study was to determine whether abdominal wall thickness (AWT) is predictive of SSI.

METHODS

We queried our American College of Surgeons National Surgical Quality Improvement Project (ACS-NSQIP) database for patients (age ≥18 years) undergoing a colectomy at the University of Kentucky (UK) from January 1, 2013 to December 31, 2018. The exclusion criteria included patients with open abdomens or the lack of preoperative computed tomography (CT) within 3 months of their operation. AWT was measured at the level of the anterior superior iliac spine (ASIS) on abdominal CT. SSI was defined by superficial SSI, deep SSI, and wound dehiscence.

RESULTS

Of 1261 patients enrolled, 52.2% were female, with an average age of 57.4 years. More patients had laparoscopic operations (51%), and the median length of stay was 7 days. Our study demonstrated an SSI rate of 9.4% and a 30-day readmission rate of 11%. The overall mean AWT was 2.6 cm (range .1-13.1), and patients with the highest AWT quintile were more likely to develop an SSI than the lowest quintile (12% vs. 5%). After controlling for risk factors and confounders, the odds of an SSI were 3.6 times higher for patients with the highest AWT than patients with the lowest AWT.

CONCLUSIONS

Among colorectal surgery patients, AWT is an independent risk factor predictive for SSI.

Review of Colonic Anastomotic Leakage and Prevention Methods

Although surgeries involving anastomosis are relatively common, anastomotic leakages are potentially deadly complications of colorectal surgeries due to increased risk of morbidity and mortality. As a result of the potentially fatal effects of anastomotic leakages, a myriad of techniques and treatments have been developed to treat these unfortunate cases. In order to better understand the steps taken to treat this complication, we have created a composite review involving some of the current and best treatments for colonic anastomotic leakage that are available. The aim of this article is to present a background review of colonic anastomotic leakage, as well as current strategies to prevent and treat this condition, for a broader audience, including scientist, engineers, and especially biomedical engineers.

Preoperative assessment of patient comorbidities before left colectomy: Comparison between ASA performance status scale and a new computed tomography physical status score

PURPOSE

To compare a newly developed preoperative computed tomography physical status (CT-PS) score with the American Society of Anesthesiology performance status (ASA-PS) scale in the assessment of patient preoperative health status and stratification of perioperative risk before left colectomy.

MATERIALS AND METHODS

Preoperative chest-abdomen-pelvis CT examinations of patients who were scheduled to undergo elective laparoscopic left colonic resection for cancer in two centers were reviewed by two radiologists blinded to clinical data for the presence of several key imaging features in order to assess general, cardiac, pulmonary, abdominal, renal, vascular and musculoskeletal status. CT examinations of patients from center 1 were used to build a CT-PS score to predict ASA-PS≥III. CT-PS score was further validated using an external cohort of patients from center 2.

RESULTS

During a 2-year period, 117 consecutive patients (63 men, 54 women; mean age, 65±13 [SD] years; age range: 53-90 years) who underwent laparoscopic left colectomy for cancer in center 1 (66 patients, building cohort) and center 2 (51 patients, validation cohort) were retrospectively included. Ninety-one percent of patients were ASA-PS 1-2. Overall postoperative morbidity was 23% and severe morbidity 12%. The area under the receiver operating characteristic curve of CT-PS score was 0.968 (95% CI: 0.901-1.000) in the building cohort and 0.828 (95% CI: 0.693-0.963) in the validation cohort. The optimal thresholds yielded 87% (95% CI: 83-91%) sensitivity and 100% (95% CI: 91-100%) specificity in the building cohort and 75% (95% CI: 69-81%) sensitivity and 83% (95% CI: 77-88%) specificity in the validation cohort for the prediction of ASA-PS.

CONCLUSION

Preoperative chest-abdomen-pelvis CT thoroughly and wisely read is highly accurate to differentiate patients with ASA-PS I/II from those with ASA-PS III/IV before left colectomy.

The ratio of abdominal depth to body mass index is a preoperative predictor of postoperative complications after laparoscopic pancreaticoduodenectomy: a retrospective propensity score matched analysis

BACKGROUND

Postoperative complication rates after laparoscopic pancreaticoduodenectomy (LPD) remain high despite improvements in perioperative management. Measurements on computed tomography imaging of intra-abdominal tissue have not been thoroughly investigated as predictors of mortality and morbidity following LPD. The aim of this study was to assess whether the ratio of abdominal depth and body mass index (AD/BMI ratio) could predict postoperative complications following LPD.

METHODS

We retrospectively analyzed 231 patients who underwent LPD and had a computed tomography scan between 2014 and 2018. Demographic, radiologic, and pathologic data were correlated to the occurrence of postoperative complications. Propensity score matching was performed to minimize selection biases associated with the comparison of retrospective data between the high and low AD/BMI ratio groups. Univariate and multivariate analyses were also performed to assess the risk factors for postoperative complications.

RESULTS

Of the 102 patients identified for propensity score matching analysis, 29 patients (28.4%) experienced postoperative complications. Patients with a high AD/BMI ratio had a higher prevalence of overall complications (45.1% vs. 11.8%, P < 0.001), postoperative pancreatic fistula (17.6% vs. 2.00%, P = 0.008), delayed gastric emptying (33.3% vs. 3.90%, P < 0.001), and intra-abdominal abscess (17.6% vs. 0, P = 0.002). In the multivariate analysis, an AD/BMI ratio greater than 2.7 (m³/[kg·10³]; OR = 6.16, 95% confidence interval [1.04-36.4], P = 0.045) was the only independent predictive factor of postoperative complications.

CONCLUSIONS

The preoperative AD/BMI ratio is a predictor of postoperative complications following LPD.

Association of Allostatic Load with All-Cause andCancer Mortality by Race and Body Mass Index in theREGARDS Cohort

Among 29,701 Black and White participants aged 45 years and older in the Reasons for Geographic and Racial Difference in Stroke (REGARDS) study, allostatic load (AL) was defined as the sum score of established baseline risk-associated biomarkers for which participants exceeded a set cutoff point. Cox proportional hazard regression was utilized to determine the association of AL score with all-cause and cancer-specific mortality, with analyses stratified by body-mass index, age group, and race. At baseline, Blacks had a higher AL score compared with Whites (Black mean AL score: 2.42, SD: 1.50; White mean AL score: 1.99, SD: 1.39; p < 0.001). Over the follow-up period, there were 4622 all-cause and 1237 cancer-specific deaths observed. Every unit increase in baseline AL score was associated with a 24% higher risk of all-cause (HR: 1.24, 95% CI: 1.22, 1.27) and a 7% higher risk of cancer-specific mortality (HR: 1.07, 95% CI: 1.03, 1.12). The association of AL with overall- and cancer-specific mortality was similar among Blacks and Whites and across age-groups, however the risk of cancer-specific mortality was higher among normal BMI than overweight or obese participants. In conclusion, a higher baseline AL score was associated with increased risk of all-cause and cancer-specific mortality among both Black and White participants. Targeted interventions to patient groups with higher AL scores, regardless of race, may be beneficial as a strategy to reduce all-cause and cancer-specific mortality.

Perioperative Heart-Brain Axis Protection in Obese Surgical Patients: The Nutrigenomic Approach

The number of obese patients undergoing cardiac and noncardiac surgery is rapidly increasing because they are more prone to concomitant diseases, such as diabetes, thrombosis, sleep-disordered breathing, cardiovascular and cerebrovascular disorders. Even if guidelines are already available to manage anesthesia and surgery of obese patients, the assessment of the perioperative morbidity and mortality from heart and brain disorders in morbidly obese surgical patients will be challenging in the next years. The present review will recapitulate the new mechanisms underlying the Heart-brain Axis (HBA) vulnerability during the perioperative period in healthy and morbidly obese patients. Finally, we will describe the nutrigenomics approach, an emerging noninvasive dietary tool, to maintain a healthy body weight and to minimize the HBA propensity to injury in obese individuals undergoing all types of surgery by personalized intake of plant compounds that may regulate the switch from health to disease in an epigenetic manner. Our review provides current insights into the mechanisms underlying HBA response in obese surgical patients and how they are modulated by epigenetically active food constituents.

Impact of adiposity on staging and prognosis of colorectal cancer

Abdominal visceral fat is a well-recognized a risk for colorectal cancer (CRC). In contrast to the risk for CRC, the impact of adiposity in disease staging and patient survival is less well-established. Our aim was to critically review the literature on the influence of adiposity assessed by different methods routinely used in clinical settings, on CRC staging and prognosis. In the 32 studies reviewed, overweight was initially identified as a survival advantage, an evidence that was later challenged by studies suggesting that body adiposity is likely to have a deleterious effect in CRC outcomes, particularly in males. Hence, whether obesity has a negative impact in CRC staging or prognosis remains controversial. In sum, addressing the impact of body fat in CRC biological behavior is still an unmet need. Understanding how adiposity influences CRC staging and prognosis could allow further patient risk stratification for devising targeted interventions and improve clinical outcomes.

Association of Obesity With Septic Complications After Major Abdominal Surgery: A Secondary Analysis of the RELIEF Randomized Clinical Trial

IMPORTANCE

Body mass index (BMI) has been the most common obesity measure to assess perioperative risk; however, cardiometabolic risk is associated with the burden of visceral fat. Definitive evidence on the association of visceral fat measures, such as waist circumference and waist-to-hip ratio (WHR), with postoperative complications is lacking.

OBJECTIVE

To compare the value of waist circumference with the value WHR and BMI in predicting adverse outcomes, including major septic complications and persistent disability, following major abdominal surgery.

DESIGN, SETTING, AND PARTICIPANTS

This planned secondary analysis of the Restrictive vs Liberal Fluid Therapy for Major Abdominal Surgery (RELIEF) randomized clinical trial took place at 47 centers in 7 countries between October 2013 and September 2016, with 90-day follow-up. A total of 2954 adult RELIEF participants were coenrolled in this secondary analysis. Data analysis took place from December 2018 to September 2019.

EXPOSURES

Waist circumference, WHR, and BMI measurements.

MAIN OUTCOMES AND MEASURES

The primary outcomes were 30-day major septic complications and 90-day persistent disability or death.

RESULTS

Of 2954 eligible participants, 2755 were included (mean [SD] age, 65.9 [12.9] years; 1426 [51.8%] men) in the final analysis. A total of 564 participants (20.6%) experienced at least 1 major septic complication within 30 days after surgery (sepsis, 265 [9.7%]; surgical site infection, 409 [14.9%]; anastomotic leak, 78 [2.8%]; pneumonia, 104 [3.8%]). Waist circumference had a statistically significantly larger odds ratio (OR) and discrimination indices as well as a smaller prediction error than WHR or BMI for 30-day major septic complications or death (waist circumference: OR, 1.44; 95% CI, 1.28-1.62; P < .001; area under the receiver operating characteristic curve, 0.641; net reclassification index, 0.266; integrated discrimination improvement [score × 104], 152.98; Brier score, 0.162; WHR: OR, 1.15; 95% CI, 1.03-1.28; P = .01; area under the receiver operating characteristic curve, 0.621; net classification index, 0.199; integrated discrimination improvement [score × 104], 28.47; Brier score, 0.164; BMI: OR, 1.33; 95% CI, 1.17-1.50; P < .001; area under the receiver operating characteristic curve, 0.629; net reclassification index, 0.205; integrated discrimination improvement [score × 104], 85.61; Brier score, 0.163) but not for any other outcomes.

CONCLUSIONS AND RELEVANCE

In this secondary analysis of the RELIEF randomized clinical trial, waist circumference was observed to be superior to other adiposity indices in predicting 30-day major septic complications alone or in conjunction with death following elective major abdominal surgery. Findings suggest that waist circumference is a useful adiposity measure that should be incorporated in preoperative risk assessment for such complications.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01424150.

Predicting and Preventing Postoperative Outcomes

Complications after colorectal surgery are common. Given the frequency of postoperative complications and their implications on quality of life, it is important to know how to predict and prevent the complications that we encounter. This article aims to provide ways to predict and prevent postoperative complications in colorectal surgery. Here, we review the predictive models, American College of Surgeons National Surgery Quality Improvement Program risk calculator and Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity on their practicality and usefulness. Additionally, this review summarizes nonmodifiable and modifiable risk factors in colorectal surgery, which are important for surgeons to understand to minimize and attempt to avoid postoperative complications as well as providing ways to optimize patients preoperatively. Thus, this review will provide information to surgeons to predict and prevent postoperative complications, how to optimize patients preoperatively and ultimately to help reduce their occurrence.

How Anesthetic, Analgesic and Other Non-Surgical Techniques During Cancer Surgery Might Affect Postoperative Oncologic Outcomes: A Summary of Current State of Evidence

The question of whether anesthetic, analgesic or other perioperative intervention during cancer resection surgery might influence long-term oncologic outcomes has generated much attention over the past 13 years. A wealth of experimental and observational clinical data have been published, but the results of prospective, randomized clinical trials are awaited. The European Union supports a pan-European network of researchers, clinicians and industry partners engaged in this question (COST Action 15204: Euro-Periscope). In this narrative review, members of the Euro-Periscope network briefly summarize the current state of evidence pertaining to the potential effects of the most commonly deployed anesthetic and analgesic techniques and other non-surgical interventions during cancer resection surgery on tumor recurrence or metastasis.

Natural history of percutaneous drainage of postoperative collection following colorectal surgery: in which patients can follow-up imaging be dispensed with before drain removal?

INTRODUCTION

Colorectal surgery is complicated by postoperative collections in up to 25% of cases depending on local conditions. The aim of this study was to identify predictive factors of success of percutaneous drainage of collections in order to avoid follow-up imaging.

PATIENTS AND METHODS

All consecutive patients between January 2009 and December 2016, who had undergone elective or emergency colorectal surgery (colorectal surgery and appendectomy) complicated by a postoperative collection treated by percutaneous drainage with follow-up imaging prior to drain removal, were included in this single-center and retrospective study. The primary objective was to assess predictive factors of success of the first attempt of percutaneous drainage of collections. Secondary objectives were to describe the natural history of percutaneous drainage of postoperative collections after colorectal surgery and the overall success rate of percutaneous drainage.

RESULTS

Fifty-three patients underwent percutaneous drainage of a postoperative collection during the study period and were included in this study. Complete resolution of the collection was observed on the first follow-up radiological examination in 36 patients (58%). In multivariate analysis, post-appendectomy collections (OR = 3.19 (1.14-9.27), p = 0.002) and reduction of the leukocyte count (OR = 3.22 (1.28-8.1), p = 0.013) were significantly associated with success of percutaneous drainage.

CONCLUSION

This is the first study to address that follow-up imaging prior to drain removal might not be necessary in patients undergoing drainage of post-appendectomy collections and/or with more than 30% reduction of the leukocyte count at the first follow-up examination.

Effect of Physical Parameters on Outcomes of Total Knee Arthroplasty

BACKGROUND

Increasing body mass index (BMI) has been shown to correlate with increased rates of complications after total knee arthroplasty. To our knowledge, body surface area, body mass, and height have not been investigated in this manner. BMI and body surface area are affected differently by changes in height, and they are affected similarly by changes in weight. The purpose of this study was to quantify revision for any reason, mechanical failure, aseptic loosening, polyethylene wear, reoperation, and any infection after total knee arthroplasty using BMI, body surface area, body mass, and height as continuous variables.

METHODS

Prospectively collected data from a single institution's total joint registry were used to analyze 22,243 consecutive knees, in 16,106 patients, treated with a primary total knee arthroplasty from 1985 to 2012. The Kaplan-Meier survival method was used to evaluate revision and other common complications, with outcomes assessed using Cox regression analysis. Smoothing spline parameterization was used on physical parameters in these models.

RESULTS

Increasing BMI, body surface area, body mass, and height were associated with an increased risk of any revision surgical procedure, mechanical failure, and aseptic loosening after total knee arthroplasty. The risk of a revision surgical procedure was directly associated with each 1 standard deviation increase in BMI (hazard ratio [HR], 1.19; p < 0.01), body surface area (HR, 1.37; p < 0.01), body mass (HR, 1.30; p < 0.01), and height (HR, 1.22; p < 0.01). This association was especially demonstrated with revision for mechanical failure (BMI: HR, 1.15; p < 0.01; body surface area: HR, 1.35; p < 0.01; body mass: HR, 1.27; p < 0.01; and height: HR, 1.23; p < 0.01). The risk of failure in the subgroups of mechanical failure including a revision surgical procedure for aseptic loosening or polyethylene wear was also associated with increasing body surface area, body mass, and height. Increasing BMI (HR, 1.22; p < 0.01), body surface area (HR, 2.56; p < 0.01), and body mass (HR, 2.54; p < 0.01) were also associated with increased risk of any infection.

CONCLUSIONS

Increasing BMI, body surface area, body mass, and height were strongly associated with the rates of revision, aseptic loosening, and other common complications following total knee arthroplasty. Body surface area and body mass appear to correlate more strongly with mechanical failure outcomes than BMI or height.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The association between body mass index and postoperative complications, 30-day mortality and long-term survival in Dutch patients with colorectal cancer

INTRODUCTION

This retrospective study aims to examine the association between body mass index (BMI) and serious postoperative complications, 30-day mortality and overall survival in colorectal cancer (CRC) patients.

MATERIALS AND METHODS

All CRC patients diagnosed between 2008 and 2013 in the south-eastern part of the Netherlands were included. Patients were categorized into four BMI groups: underweight (<18.5), normal weight (18.5 ≥ BMI<25), overweight (25 ≥ BMI<30), and obese (≥30).

RESULTS

A total of 7371 CRC patients were included (underweight 133 (1.8%); normal weight 2054 (41.4%); overweight 2955 (40.1%); obesity 1229 (16.7%)). Underweight patients were more likely to have postoperative complications (18.8% vs. 11.7%, adjusted OR 1.95, 95% CI 1.08-3.49) and had a worse 30-day mortality (9.8% vs. 3.3%, adjusted OR 4.37, 95% CI 2.03-9.42) compared to normal weight patients. After stratification for stage (stage I-III and stage IV), underweight was associated with a worse overall survival in both groups compared to normal weight (stage I-III: HR 2.06, 95%CI 1.51-2.80; stage IV: HR 1.65, 95% CI 1.11-2.45). Overweight was associated with an improved overall survival compared to normal weight in both stage groups. Only in stage IV patients obesity was associated with a significant better overall survival compared to stage IV normal weight patients.

CONCLUSION

Underweight CRC patients were more likely to have postoperative complications and a worse 30-day mortality compared to patients in other BMI categories. The underweight population also has a worse long-term survival while overweight CRC patients and obese stage IV CRC patients were associated with an improved survival compared to normal weight patients.

Visceral fat area, not body mass index, predicts postoperative 30-day morbidity in patients undergoing colon resection for cancer

PURPOSE

Colectomy for cancer in obese patients is technically challenging and may be associated with worse outcomes. Whether visceral obesity, as measured on computed tomography, is a better predictor of complication than body mass index (BMI) or determines long-term oncologic outcomes has not been well characterized. This study examines the association between derived anthropometrics and postoperative complication and long-term oncologic outcomes.

METHODS

Retrospective review of patients undergoing elective colectomy for cancer at a single tertiary-care center from 2010 to 2016. Adipose tissue distribution measurements, including visceral fat area (VFA), were determined from preoperative imaging. The primary outcome was 30-day postoperative complication; secondary outcomes included overall and disease-free survival. Multivariable logistic regression was performed to determine association between obesity metrics and outcome.

RESULTS

Two hundred and sixty-four patients underwent 266 primary resections of colon cancer. Twenty-eight patients (10.5%) developed major morbidity (Clavien-Dindo grade ≥ III). VFA but not BMI was significantly associated with morbidity in multivariate analysis (p = 0.004, odds ratio 1.99, 95% confidence interval 1.25-3.19). No other imaging-derived anthropometric was associated with increased morbidity. In receiver operating characteristic analysis, VFA was predictive of major morbidity (area under curve 0.660). A cutoff value of VFA ≥ 191 cm² was associated with 50% sensitivity and 76% specificity for predicting major morbidity. Patients with VFA ≥ 191cm² had 19.4% risk of morbidity, whereas those with < 191 cm² had 7.2% risk (relative risk ratio 2.69, unadjusted p = 0.004). Neither VFA nor BMI was associated with overall or disease-free survival.

CONCLUSION

VFA but not BMI predicts morbidity following elective surgery for colon cancer.

Obesity as a determinant of perioperative and postoperative outcome in patients following colorectal cancer surgery: A population-based study (2009-2016)

BACKGROUND

Obesity is an increasing problem worldwide that can influence perioperative and postoperative outcomes. However, the relationship between obesity and treatment-related perioperative and short-term postoperative morbidity after colorectal resections is still subject to debate.

STUDY

Patients were selected from the DCRA, a population-based audit including 83 hospitals performing colorectal cancer (CRC) surgery. Data regarding primary resections between 2009 and 2016 were eligible for analyses. Patients were subdivided into six categories: underweight, normal weight, overweight and obesity class I, II and III.

RESULTS

Of 71,084 patients, 17.7% with colon and 16.4% with rectal cancer were categorized as obese. Significant differences were found for the 30-day overall postoperative complication rate (p < 0.001), prolonged hospitalization (p < 0.001) and readmission rate (colon cancer p < 0.005; rectal cancer p < 0.002) in obese CRC patients. Multivariate analysis identified BMI ≥30 kg/m² as independent predictor of a complicated postoperative course in CRC patients. Furthermore, obesity-related comorbidities were associated with higher postoperative morbidity, prolonged hospitalization and a higher readmission rate. No significant differences in performance were observed in postoperative outcomes of morbidly obese CRC patients between hospitals performing bariatric surgery and hospitals that did not.

CONCLUSION

The real-life data analysed in this study reflect daily practice in the Netherlands and identify obesity as a significant risk factor in CRC patients. Obesity-related comorbidities were associated with higher postoperative morbidity, prolonged hospitalization and a higher readmission rate in obese CRC patients. No differences were observed between hospitals performing bariatric surgery and hospitals that did not.

The use of consumer depth cameras for 3D surface imaging of people with obesity: A feasibility study

OBJECTIVE

Three dimensional (3D) surface imaging is a viable alternative to traditional body morphology measures, but the feasibility of using this technique with people with obesity has not been fully established. Therefore, the aim of this study was to investigate the validity, repeatability and acceptability of a consumer depth camera 3D surface imaging system in imaging people with obesity.

METHODS

The concurrent validity of the depth camera based system was investigated by comparing measures of mid-trunk volume to a gold-standard. The repeatability and acceptability of the depth camera system was assessed in people with obesity at a clinic.

RESULTS

There was evidence of a fixed systematic difference between the depth camera system and the gold standard but excellent correlation between volume estimates (r²=0.997), with little evidence of proportional bias. The depth camera system was highly repeatable - low typical error (0.192L), high intraclass correlation coefficient (>0.999) and low technical error of measurement (0.64%). Depth camera based 3D surface imaging was also acceptable to people with obesity.

CONCLUSION

It is feasible (valid, repeatable and acceptable) to use a low cost, flexible 3D surface imaging system to monitor the body size and shape of people with obesity in a clinical setting.

Abdominal obesity and metabolic syndrome: exercise as medicine?

Background

Metabolic syndrome is defined as a cluster of at least three out of five clinical risk factors: abdominal (visceral) obesity, hypertension, elevated serum triglycerides, low serum high-density lipoprotein (HDL) and insulin resistance. It is estimated to affect over 20% of the global adult population. Abdominal (visceral) obesity is thought to be the predominant risk factor for metabolic syndrome and as predictions estimate that 50% of adults will be classified as obese by 2030 it is likely that metabolic syndrome will be a significant problem for health services and a drain on health economies.

Evidence shows that regular and consistent exercise reduces abdominal obesity and results in favourable changes in body composition. It has therefore been suggested that exercise is a medicine in its own right and should be prescribed as such.

Purpose of this review

This review provides a summary of the current evidence on the pathophysiology of dysfunctional adipose tissue (adiposopathy). It describes the relationship of adiposopathy to metabolic syndrome and how exercise may mediate these processes, and evaluates current evidence on the clinical efficacy of exercise in the management of abdominal obesity. The review also discusses the type and dose of exercise needed for optimal improvements in health status in relation to the available evidence and considers the difficulty in achieving adherence to exercise programmes.

Conclusion

There is moderate evidence supporting the use of programmes of exercise to reverse metabolic syndrome although at present the optimal dose and type of exercise is unknown. The main challenge for health care professionals is how to motivate individuals to participate and adherence to programmes of exercise used prophylactically and as a treatment for metabolic syndrome.

Can Patient Selection Explain the Obesity Paradox in Orthopaedic Hip Surgery? An Analysis of the ACS-NSQIP Registry

BACKGROUND

The "obesity paradox" is a phenomenon described in prior research in which patients who are obese have been shown to have lower postoperative mortality and morbidity compared with normal-weight individuals. The paradox is that clinical experience suggests that obesity is a risk factor for difficult wound healing and adverse cardiovascular outcomes. We suspect that the obesity paradox may reflect selection bias in which only the healthiest patients who are obese are offered surgery, whereas nonobese surgical patients are comprised of both healthy and unhealthy individuals. We questioned whether the obesity paradox (decreased mortality for patients who are obese) would be present in nonurgent hip surgery in which patients can be carefully selected for surgery but absent in urgent hip surgery where patient selection is minimized.

QUESTIONS/PURPOSES

(1) What is the association between obesity and postoperative mortality in urgent and nonurgent hip surgery? (2) How is obesity associated with individual postoperative complications in urgent and nonurgent hip surgery? (3) How is underweight status associated with postoperative mortality and complications in urgent and nonurgent hip surgery?

METHODS

We used 2011 to 2014 data from the American College of Surgeons National Surgical Quality Improvement Project (ACS-NSQIP) to identify all adults who underwent nonurgent hip surgery (n = 63,148) and urgent hip surgery (n = 29,047). We used logistic regression models, controlling for covariants including age, sex, anesthesia risk, and comorbidities, to examine the relationship between body mass _index (BMI) category (classified as underweight < 18.5 kg/m, normal 18.5-24.9 kg/m, overweight 25-29.9 kg/m, obese 30-39.9 kg/m, and morbidly obese > 40 kg/m) and adverse outcomes including 30-day mortality and surgical complications including wound complications and cardiovascular events.

RESULTS

For patients undergoing nonurgent hip surgery, regression models demonstrate that patients who are morbidly obese were less likely to die within 30 days after surgery (odds ratio [OR], 0.12; 95% confidence interval [CI], 0.01-0.57; p = 0.038) compared with patients with normal BMI, consistent with the obesity paradox. For patients undergoing urgent hip surgery, patients who are morbidly obese had similar odds of death within 30 days compared with patients with normal BMI (OR, 1.18; 95% CI, 0.76-1.76; p = 0.54). Patients who are morbidly obese had higher odds of wound complications in both nonurgent (OR, 4.93; 95% CI, 3.68-6.65; p < 0.001) and urgent cohorts (OR, 4.85; 95% CI, 3.27-7.01; p < 0.001) compared with normal-weight patients. Underweight patients were more likely to die within 30 days in both nonurgent (OR, 3.79; 95% CI, 1.10-9.97; p = 0.015) and urgent cohorts (OR, 1.47; 95% CI, 1.23-1.75; p < 0.001) compared with normal-weight patients.

CONCLUSIONS

Patients who are morbidly obese appear to have a reduced risk of death in 30 days after nonurgent hip surgery, but not for urgent hip surgery. Our results suggest that the obesity paradox may be an artifact of selection bias introduced by careful selection of the healthiest patients who are obese for elective hip surgery. Surgeons should continue to consider obesity a risk factor for postoperative mortality and complications such as wound infections for both urgent and nonurgent surgery.

LEVEL OF EVIDENCE

Level III, therapeutic study.

The influence of metabolic syndrome in the outcomes of colorectal cancer patients

AIMS

Determine the influence of metabolic syndrome and its different components in the outcomes of colorectal cancer surgery at 30days.

MATERIALS AND METHODS

Prospective study that included all patients submitted to elective colorectal cancer surgery between August 2015 and August 2016 at Hospital de Braga. Clinical and laboratory parameters evaluated pre-operatively were: central obesity, blood pressure, fasting glucose, triglycerides levels and HDL cholesterol levels. Any complications during the first 30-days after surgery were recorded (readmission, reintervention, anastomotic dehiscence, morbimortality).

RESULTS

One hundred and thirty-four patients were included. Metabolic syndrome was diagnostic in 40.7% of patients with the ATPIII definition, 67.5% with the AHA definition and 67.0% with the IDF definition. At 30days after colorectal cancer surgery, 73.1% patients don't have any complication, 15.7% have minor complications (grade I/II of Clavien-Dindo classification), 11.1% have major complications (grade III/IV/V of Clavien-Dindo classification) and 1.5% have died from surgical complications (grade V of Clavien-Dindo classification). The statistic analysis didn't reveal any association between MS, or it's different components, and surgical outcomes.

CONCLUSION

This study seems to indicate that metabolic syndrome don't have any influence in surgical outcomes of colorectal cancer surgery.

Maternal obesity and major intraoperative complications during cesarean delivery

BACKGROUND

Multiple studies have demonstrated an association between maternal obesity and postoperative complications, but there is a dearth of information about the impact of obesity on intraoperative complications.

OBJECTIVE

To estimate the association between maternal obesity at delivery and major intraoperative complications during cesarean delivery (CD).

METHODS

This is a secondary analysis of the deidentified Maternal-Fetal Medicine Unit Cesarean Registry of women with singleton pregnancies. Maternal body mass index (BMI) at delivery was categorized as BMI 18.5 to 29.9 kg/m², BMI 30 to 39.9 kg/m², BMI 40 to 49.9 kg/m², and BMI ≥ 50 kg/m². The primary outcome, any intraoperative complication, was defined as having at least 1 major intraoperative complication, including perioperative blood transfusion, intraoperative injury (bowel, bladder, ureteral injury; broad ligament hematoma), atony requiring surgical intervention, repeat laparotomy, and hysterectomy. Log-binomial models were used to estimate risk ratios of intraoperative complication in 2 models: model 1 adjusting for maternal race, and preterm delivery <37 weeks; and model 2 adjusting for confounders in Model 1 as well as emergency CD, and type of skin incision.

RESULTS

A total of 51,218 women underwent CD; 38% had BMI 18.5 to 29.9 kg/m², 47% BMI 30 to 39.9 kg/m², 12% BMI 40 to 49.9 kg/m² and 3% BMI ≥ 50 kg/m². Having at least 1 intraoperative complication was uncommon (3.4%): 3.8% for BMI 18.5 to 29.9 kg/m², 3.2% BMI 30 to 39.9 kg/m², 2.6% BMI 40 to 49.9 kg/m² and 4.3% BMI ≥ 50 kg/m² (P < .001). In the fully adjusted model 2, women with BMI 40 to 49.9 kg/m² had a lower risk of any intraoperative complication (adjusted risk ratio [ARR], 0.76; 95% confidence interval [CI], 0.64 to 0.89) compared with women with BMI 18.5 to 29.9 kg/m². Women with BMI 30 to 39.9 kg/m² (ARR, 0.93; 95% CI, 0.84 to 1.03) had a similar risk of any intraoperative complication compared with nonobese women. Among super obese women, there was evidence of effect modification by emergency CD. Compared with nonobese women, neither super obese women undergoing nonemergency CD (ARR, 1.13; 95% CI, 0.84 to 1.52) nor those undergoing emergency CD (ARR, 0.59; 95% CI, 0.32 to 1.10) had an increased risk of intraoperative complication.

CONCLUSION

In contrast to the risk for postcesarean complications, the risk of intraoperative complication does not appear to be increased in obese women, even among those with super obesity.

BMI as a Predictor for Perioperative Outcome of Laparoscopic Colorectal Surgery: a Pooled Analysis of Comparative Studies

BACKGROUND

There has been a long-lasting controversy about whether higher BMI is associated with worse perioperative outcomes of laparoscopic colorectal surgery. Recently, a number of newly published investigations have made it possible to draw a quantitative conclusion.

OBJECTIVE

We conducted this comprehensive meta-analysis to clarify the exact effect that BMI imposes on perioperative outcome of laparoscopic colorectal surgery.

DATA SOURCES

We systematically searched MEDLINE, Embase, and Cochrane Library databases to identify all relevant studies.

STUDY SELECTION

Comparative studies in English that investigated perioperative outcome of laparoscopic colorectal surgery for patients with different BMIs were included. Quality of studies was evaluated by using the Newcastle-Ottawa Scale.

INTERVENTION

The risk factor of interest was BMI.

MAIN OUTCOME MEASURES

Effective sizes were pooled under a random-effects model to evaluate preoperative, intraoperative, and postoperative outcomes.

RESULTS

A total of 43 studies were included. We found that higher BMI was associated with significantly longer operative time (p < 0.001), greater blood loss (p = 0.01), and higher incidence of conversion to open surgery (p < 0.001). Moreover, BMI was a risk factor for overall complication rates (p < 0.001), especially for ileus (p = 0.02) and events of the urinary system (p = 0.03). Significant association was identified between higher BMI and risk of surgical site infection (p < 0.001) and anastomotic leakage (p = 0.02). Higher BMI might also led to a reduced number of harvest lymph nodes for patients with colorectal cancer (p = 0.02). The heterogeneity test identified no significant cross-study heterogeneity, and the results of cumulative meta-analysis, sensitivity analysis, and the publication bias test verified the reliability of our study.

LIMITATIONS

Most studies included were retrospectively designed.

CONCLUSIONS

Body mass index is a practical and valuable measurement for the prediction of the perioperative outcome of laparoscopic colorectal surgery. Higher BMI is associated with worse perioperative outcome. More accurate conclusions, with more precise cutoff values, can be achieved by future well-designed prospective investigations.

Increased mid-abdominal circumference is a predictor for surgical wound complications in kidney transplant recipients: A prospective cohort study

Kidney transplant recipients are at an increased risk of developing surgical site wound complications due to their immunosuppressed status. We aimed to determine whether increased mid-abdominal circumference (MAC) is predictive for wound complications in transplant recipients. A prospective study was performed on all kidney transplant recipients from October 2014 to October 2015. "Controls" consisted of kidney transplant recipients without a surgical site wound complication and "cases" consisted of recipients that developed a wound complication. In total, 144 patients underwent kidney transplantation and 107 patients met inclusion criteria. Postoperative wound complications were documented in 28 (26%) patients. Patients that developed a wound complication had a significantly greater MAC, body mass index (BMI), and body weight upon renal transplantation (P<.001, P=.011, and P=.011, respectively). On single and multiple logistic regression analyses, MAC was a significant predictor for developing a surgical wound complication (P=.02). Delayed graft function and a history of preformed anti-HLA antibodies were also predictive for surgical wound complications (P=.003 and P=.014, respectively). Increased MAC is a significant predictor for surgical wound complications in kidney transplant recipients. Integrating clinical methods for measuring visceral adiposity may be useful for stratifying kidney transplant recipients with an increased risk of a surgical wound complication.

Impact of body mass index and gender on wound complications after lower extremity arterial surgery

OBJECTIVE

Wound complications (WCs) after lower extremity arterial surgery (LEAS) are common, resulting in readmissions and reinterventions. Whereas diabetes and obesity are known risk factors for WCs, gender-specific variability in body fat distribution (android vs gynoid) may drive differential risks of WCs after LEAS. We analyzed the independent and synergistic effects of gender and body mass index (BMI) on WCs.

METHODS

We performed a retrospective review of prospectively collected data from a published, randomized, multicenter trial assessing the incidence of WCs (dehiscence, surgical site infections, seroma, and hematoma) after LEAS. Postoperative outcomes were compared between genders. A multivariable regression model assessed the impact of gender and BMI on WCs. Subanalysis focused on the synergy of gender and body habitus, groin-only incisions, and clinical outcomes.

RESULTS

There were 502 patients who underwent LEAS between October 2010 and September 2013. The cohort was elderly (67.6 ± 10.5 years), mostly male (72%), and overweight (BMI, 27.6 ± 5.7); 225 (45%) patients had a groin-only incision. In 171 patients (37.9%), a WC developed within 30 days, 85% of which were infectious in etiology. On multivariable regression, obesity (odds ratio [OR], 2.10; 95% confidence interval [CI], 1.17-3.77), morbid obesity (OR, 2.87; 95% CI, 1.32-6.23), and female gender (OR, 1.17; 95% CI, 1.06-2.75) were independent predictors of infectious WCs at 30 days. When stratified by groin-only incision, BMI was no longer significant, but female gender (OR, 2.70; 95% CI, 1.24-5.87) was predictive of infectious WCs at 30 days. There was no synergistic effect of BMI and gender on WCs.

CONCLUSIONS

WCs are common after LEAS. BMI is an independent risk factor for the development of any WC. Female gender, a potential surrogate for high hip to waist ratio body habitus, is also an independent predictor of groin WCs, suggesting the clinical importance of gynoid vs android fat distribution.

Effect of Body Mass Index on Reoperation and Complications After Total Knee Arthroplasty

BACKGROUND

High body mass index (BMI) is associated with increased rates of complications after total knee arthroplasty. To date, to our knowledge, studies have examined risk as a dichotomous variable using specific BMI thresholds. The purpose of this investigation was to quantify implant survival and the risk of common complications after total knee arthroplasty using BMI as a continuous variable.

METHODS

Using prospectively collected data from our institutional total joint registry, we analyzed 22,289 consecutive knees, in 16,136 patients, treated with primary total knee arthroplasty from 1985 to 2012. The mean BMI of these patients at the time of the surgical procedure was 31.3 kg/m (range, 11 to 69 kg/m). The Kaplan-Meier survival method was used to estimate survivorship, reoperations, and common complications, with associations of outcomes assessed using a Cox regression model.

RESULTS

Utilizing smoothing spline parameterization, we found that reoperation (p < 0.001) and implant revision or removal rates (p < 0.001) increased with increasing BMI after total knee arthroplasty. Increasing BMI also was associated with increased rates of wound infection (hazard ratio [HR], 1.07; p < 0.001) and deep infection (HR, 1.08; p < 0.001) per unit of BMI over 35 kg/m. A BMI of 35 to 40 kg/m was associated with a higher rate of implant revision for aseptic loosening (p < 0.001) and for polyethylene wear (p < 0.001) compared with a BMI of 18 to 24.99 kg/m. There was no correlation between BMI and risk of venous thromboembolism, tibiofemoral instability, or need for knee manipulation.

CONCLUSIONS

The rates of reoperation, implant revision or removal, and many common complications after total knee arthroplasty were strongly associated with BMI.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Physical Activity to Reduce Systemic Inflammation Associated With Chronic Pain and Obesity: A Narrative Review

INTRODUCTION

The increasing prevalence of chronic pain and obesity has significant health and cost implications for economies in the developed and developing world. Evidence suggests that there is a positive correlation between obesity and chronic pain and the link between them is thought to be systemic inflammation.

OBJECTIVES

The aim of this narrative review was to explore the physiological links between chronic musculoskeletal pain and obesity and to consider the potential role of regular physical activity in providing a means of managing obesity-related chronic pain.

DISCUSSION

Systemic inflammation, mechanical overload, and autonomic dysfunction are associated with increased prevalence and severity of chronic pain in individuals with obesity. It has been proposed, therefore, that interventions that target systemic inflammation could help to reduce chronic pain in obese individuals. Reduction in abdominal fat has been shown to alleviate pain and reduce the systemic markers of inflammation that contribute to chronic pain. Interventions that include exercise prescription have been shown to reduce both abdominal fat and systemic inflammation. Furthermore, exercise is also known to reduce pain perception and improve mental health and quality of life that also improves pain outcomes. However, adherence to formal exercise prescription is poor and therefore exercise programmes should be tailored to the interests, needs, and abilities of individuals to reduce attrition.

Randomized open-label phase II study comparing oxycodone–naloxone with oxycodone in early return of gastrointestinal function after laparoscopic colorectal surgery

Background

Combined oral modified-release oxycodone–naloxone may reduce opioid-induced postoperative gut dysfunction. This study examined the feasibility of a randomized trial of oxycodone–naloxone within the context of enhanced recovery for laparoscopic colorectal resection.

Methods

In a single-centre open-label phase II feasibility study, patients received analgesia based on either oxycodone–naloxone or oxycodone. Primary endpoints were recruitment, retention and protocol compliance. Secondary endpoints included a composite endpoint of gut function (tolerance of solid food, low nausea/vomiting score, passage of flatus or faeces).

Results

Eighty-two patients were screened and 62 randomized (76 per cent); the attrition rate was 19 per cent (12 of 62), leaving 50 patients who received the allocated intervention with 100 per cent follow-up and retention (modified intention-to-treat cohort). Protocol compliance was more than 90 per cent. Return of gut function by day 3 was similar in the two groups: 13 (48 per cent) of 27 in the oxycodone–naloxone group and 15 (65 per cent) of 23 in the control group (95 per cent c.i. for difference −10·0 to 40·7 per cent; P = 0·264). However, patients in the oxycodone–naloxone group had a shorter time to first bowel movement (mean(s.d.) 87(38) h versus 111(37) h in the control group; 95 per cent c.i. for difference 2·3 to 45·4 h, P = 0·031) and reduced total (oral plus parenteral) opioid consumption (mean(s.d.) 78(36) versus 94(56) mg respectively; 95 per cent c.i. for difference −10·2 to 42·8 mg, P = 0·222).

Conclusion

High participation, retention and protocol compliance confirmed feasibility. Potential benefits of oxycodone–naloxone in reducing time to bowel movement and total opioid consumption could be tested in a randomized trial. Registration number: NCT02109640 (https://www.clinicaltrials.gov/).

Abdominal fat ratio - a novel parameter for predicting conversion in laparoscopic colorectal surgery

INTRODUCTION Laparoscopic surgery has become the standard for colorectal cancer resection in the UK but it can be technically challenging in patients who are obese. Patients whose body fat is mainly inside the abdominal cavity are more challenging than those whose fat is mainly outside the abdominal cavity. Abdominal fat ratio (AFR) is a simple parameter proposed by the authors to aid identification of this subgroup. MATERIALS AND METHODS All 195 patients who underwent elective, laparoscopic colorectal cancer resections from March 2010 to November 2013 were included in the study. For patients who were obese (body mass index greater than 30), preoperative staging computed tomography was used to determine AFR. This was assessed by two different, blinded observers and compared with conversion rate. RESULTS Of the 195 patients, 58 (29.7%) fell into the obese group and 137 (70.3%) into the non-obese group. The median AFR of the obese group that were converted to open surgery was significantly higher at 5.9 compared with those completed laparoscopically (3.3, P = 0.0001, Mann-Whitney). There was no significant difference in conversion rate when looking at body mass index, tumour site or size. DISCUSSION Previous studies have found body mass index, age, gender, previous abdominal surgery, site and locally advanced tumours to be associated with an increased risk of conversion. This study adds AFR to the list of risk factors. CONCLUSION AFR is a simple, reproducible parameter which can help to predict conversion risk in obese patients undergoing colorectal cancer resection.

The ability of prehabilitation to influence postoperative outcome after intra-abdominal operation: A systematic review and meta-analysis

BACKGROUND

Preoperative physical fitness is predictive of postoperative outcome. Patients with lesser aerobic capacity are at greater risk of postoperative complications, longer hospital stays, and mortality. Prehabilitation may improve physical fitness, but it is unknown whether enhanced fitness translates to an improvement in postoperative outcome.

METHODS

This systematic review and meta-analysis aimed to assess the ability of prehabilitation to influence postoperative outcome after intra-abdominal operations. Randomized controlled trials with at least 1 group undergoing a preoperative exercise intervention/prehabilitation were included. The following databases were searched: AMED, CINAHL, EMBASE, PubMed/Medline, and The Cochrane Library. Data extracted from 9 full-articles included author(s), population demographics, type of operation, postoperative measures of outcome, and type of treatment of the prehabilitation and control groups. Methodologic quality was assessed using GRADEpro, and the Cochrane risk of bias tool was used to measure study bias.

RESULTS

Prehabilitation consisting of inspiratory muscle training, aerobic exercise, and/or resistance training can decrease all types of postoperative complications after intra-abdominal operations (odds ratio: 0.59, 95% confidence interval: 0.38-0.91, P = .03). It is unclear from our meta-analysis whether prehabilitation can decrease postoperative length of stay, because the number of studies that examined length of stay was small (n = 4). No postoperative mortality was reported in any study, and conclusions could not be drawn on the ability of exercise to influence operative mortality. The methodologic quality of studies was, however, "very low."

CONCLUSION

Prehabilitation appears to be beneficial in decreasing the incidence of postoperative complications; however, more high-quality studies are needed to validate its use in the preoperative setting.

Preoperative, intraoperative and postoperative risk factors for anastomotic leakage after laparoscopic low anterior resection with double stapling technique anastomosis

Anastomotic leakage (AL) is one of the most devastating complications after rectal cancer surgery. The double stapling technique has greatly facilitated intestinal reconstruction especially for anastomosis after low anterior resection (LAR). Risk factor analyses for AL after open LAR have been widely reported. However, a few studies have analyzed the risk factors for AL after laparoscopic LAR. Laparoscopic rectal surgery provides an excellent operative field in a narrow pelvic space, and enables total mesorectal excision surgery and preservation of the autonomic nervous system with greater precision. However, rectal transection using a laparoscopic linear stapler is relatively difficult compared with open surgery because of the width and limited performance of the linear stapler. Moreover, laparoscopic LAR exhibits a different postoperative course compared with open LAR, which suggests that the risk factors for AL after laparoscopic LAR may also differ from those after open LAR. In this review, we will discuss the risk factors for AL after laparoscopic LAR.