Multicentre prospective cohort study of body mass index and postoperative complications following gastrointestinal surgery

Systemic immune-inflammation index combined with pediatric appendicitis score in assessing the severity and prognosis for paediatric appendicitis

BACKGROUND

Pediatric appendicitis is a common cause of abdominal pain in children and is recognized as a significant surgical emergency. A prompt and accurate diagnosis is essential to prevent complications such as perforation and peritonitis.

AIM

To investigate the predictive value of the systemic immune-inflammation index (SII) combined with the pediatric appendicitis score (PAS) for the assessment of disease severity and surgical outcomes in children aged 5 years and older with appendicitis.

METHODS

Clinical data of 104 children diagnosed with acute appendicitis were analyzed. The participants were categorized into the acute appendicitis group and chronic appendicitis group based on disease presentation and further stratified into the good prognosis group and poor prognosis group based on prognosis. The SII and PAS were measured, and a joint model using the combined SII and PAS was constructed to predict disease severity and surgical outcomes.

RESULTS

Significant differences were observed in the SII and PAS parameters between the acute appendicitis group and chronic appendicitis group. Correlation analysis showed associations among the SII, PAS, and disease severity, with the combined SII and PAS model demonstrating significant predictive value for assessing disease severity [aera under the curve (AUC) = 0.914] and predicting surgical outcomes (AUC = 0.857) in children aged 5 years and older with appendicitis.

CONCLUSION

The study findings support the potential of integrating the SII with the PAS for assessing disease severity and predicting surgical outcomes in pediatric appendicitis, indicating the clinical utility of the combined SII and PAS model in guiding clinical decision-making and optimizing surgical management strategies for pediatric patients with appendicitis.

Obesity and overweight are associated with worse survival in early-onset colorectal cancer

BACKGROUND

Obesity and its associated lifestyle are known risk factors for early-onset colorectal cancer and are associated with poor postoperative and survival outcomes in older patients. We aimed to investigate the impact of obesity on the outcomes of early-onset colorectal cancers.

METHODS

Retrospective review of all patients undergoing primary resection of colon or rectal adenocarcinoma at our institution between 2015-2022. Patients who had palliative resections, resections performed at another institution, appendiceal tumors, and were underweight were excluded. The primary endpoint was survival according to the patient's body mass index: normal weight (18-24.9 kg/m2), overweight (25-29.9 kg/m2), and obesity (≥30 kg/m2). Patient and tumor characteristics and survival were compared between the three groups.

RESULTS

A total of 279 patients aged <50 years with colorectal cancer were treated at our hospital; 120 were excluded from the analysis for the following reasons: main treatment or primary resection performed at another hospital (n = 97), no resection/palliative resection (n = 23), or body mass index <18 kg/m2 (n = 2). Of these, 157 patients were included in the analysis; 61 (38.9%) were overweight and 45 (28.7%) had obesity. Except for a higher frequency of hypertension in the overweight (P = .062) and obese (P = .001) groups, no differences in patient or tumor characteristics were observed. Mean overall survival was 89 months with normal weight, 92 months with overweight, and 65 months with obesity (P = .032). Mean cancer-specific survival was 95 months with normal weight, 94 months with overweight, and 68 months with obesity (P = .018). No statistically significant difference in disease-free survival (75 vs 70 vs 59 months, P = .844) was seen.

CONCLUSION

Individuals with early-onset colorectal cancer who are overweight or obese present with similar tumor characteristics and postoperative morbidity to patients with normal weight. However, obesity may have a detrimental impact on their survival. Addressing obesity as a modifiable risk factor might improve early-onset colorectal cancer prognosis.

Postoperative Complications and Mobilization Following Major Abdominal Surgery With Versus Without Fitness Tracker-based Feedback (EXPELLIARMUS): A Student-led Multicenter Randomized Controlled Clinical Trial of the CHIR-Net SIGMA Study Group

OBJECTIVE

To determine whether daily postoperative step goals and feedback through a fitness tracker (FT) reduce the rate of postoperative complications after surgery.

BACKGROUND

Early and enhanced postoperative mobilization has been advocated to reduce postoperative complications, but it is unknown whether FT alone can reduce morbidity.

METHODS

EXPELLIARMUS was performed at 11 University Hospitals across Germany by the student-led clinical trial network SIGMA. Patients undergoing major abdominal surgery were enrolled, equipped with an FT, and randomly assigned to the experimental (visible screen) or control intervention (blackened screen). The experimental group received daily step goals and feedback through the FT. The primary end point was postoperative morbidity within 30 days using the Comprehensive Complication Index (CCI). All trial visits were performed by medical students in the hospital with the opportunity to consult a surgeon-facilitator who also obtained informed consent. After discharge, medical students performed the 30-day postoperative visit through telephone and electronic questionnaires.

RESULTS

A total of 347 patients were enrolled. Baseline characteristics were comparable between the 2 groups. The mean age of patients was 58 years, and 71% underwent surgery for malignant disease, with the most frequent indications being pancreatic, colorectal, and hepatobiliary malignancies. Roughly one-third of patients underwent laparoscopic surgery. No imputation for the primary end point was necessary as data completeness was 100%. There was no significant difference in the CCI between the 2 groups in the intention-to-treat analysis (mean±SD CCI experimental group: 23±24 vs. control: 22±22; 95% CI: -6.1, 3.7; P=0.628). All secondary outcomes, including quality of recovery, 6-minute walking test, length of hospital stay, and step count until postoperative day 7 were comparable between the 2 groups.

CONCLUSIONS

Daily step goals combined with FT-based feedback had no effect on postoperative morbidity. The EXPELLIARMUS shows that medical students can successfully conduct randomized controlled trials in surgery.

Development and validation of machine learning models and nomograms for predicting the surgical difficulty of laparoscopic resection in rectal cancer

BACKGROUND

The objective of this study is to develop and validate a machine learning (ML) prediction model for the assessment of laparoscopic total mesorectal excision (LaTME) surgery difficulty, as well as to identify independent risk factors that influence surgical difficulty. Establishing a nomogram aims to assist clinical practitioners in formulating more effective surgical plans before the procedure.

METHODS

This study included 186 patients with rectal cancer who underwent LaTME from January 2018 to December 2020. They were divided into a training cohort (n = 131) versus a validation cohort (n = 55). The difficulty of LaTME was defined based on Escal's et al. scoring criteria with modifications. We utilized Lasso regression to screen the preoperative clinical characteristic variables and intraoperative information most relevant to surgical difficulty for the development and validation of four ML models: logistic regression (LR), support vector machine (SVM), random forest (RF), and decision tree (DT). The performance of the model was assessed based on the area under the receiver operating characteristic curve(AUC), sensitivity, specificity, and accuracy. Logistic regression-based column-line plots were created to visualize the predictive model. Consistency statistics (C-statistic) and calibration curves were used to discriminate and calibrate the nomogram, respectively.

RESULTS

In the validation cohort, all four ML models demonstrate good performance: SVM AUC = 0.987, RF AUC = 0.953, LR AUC = 0.950, and DT AUC = 0.904. To enhance visual evaluation, a logistic regression-based nomogram has been established. Predictive factors included in the nomogram are body mass index (BMI), distance between the tumor to the dentate line ≤ 10 cm, radiodensity of visceral adipose tissue (VAT), area of subcutaneous adipose tissue (SAT), tumor diameter >3 cm, and comorbid hypertension.

CONCLUSION

In this study, four ML models based on intraoperative and preoperative risk factors and a nomogram based on logistic regression may be of help to surgeons in evaluating the surgical difficulty before operation and adopting appropriate responses and surgical protocols.

Nutritional Risk of Candidates for Simultaneous Pancreatic-Kidney Transplantation-A Narrative Review

INTRODUCTION

Not much is known about the significance of nutritional status and support in transplant surgery, least of all in simultaneous pancreatic and kidney transplantation. Malnutrition in the context of simultaneous pancreatic-kidney transplantation seems to be complex and a still poorly investigated problem. Since SPKTX is highly qualified and also has a small volume procedure, it is difficult to obtain data from large cohorts of patients. The aim of this article is to gather existing evidence and information about the subject, as well as to elicit some questions and goals for the future.

METHODS

We searched through the Pub-Med database using the keywords "pancreas and kidney transplantation" combined with "nutritional risk", "nutritional status", "malnutrition", "nutritional intervention", and "frailty", finding a total of 4103 matching results. We then narrowed it down to articles written in English with the full text available. We also researched through the references of articles most accurately matching our researched terms.

RESULTS

There are numerous tools that have been investigated for the screening of malnutrition, such as the NRI index, PNI index, NLR, SGA scale, and NRS-2002 scale, each of which proved to be of some use in predicting patient outcomes in different surgical settings. Since all of them differed in components and assessed parameters and, in the absence of more sensitive or infallible indicators, the most reasonable approach seems to evaluate them jointly.

CONCLUSION

It is important to underline the necessity of nutritional screening and the subsequent introduction of adequate therapy while awaiting transplantation in an attempt to improve results. Considering the complexity of surgical procedures and the severity of underlying diseases with their intense metabolic components, the patient's nutritional status seems to significantly influence results. Consequently, nutritional risk assessments should be a part of the routine care of patients qualified for transplantation.

Effect of obesity on perioperative outcomes following gastrointestinal surgery: meta-analysis

BACKGROUND

Obesity can pose perioperative challenges related to obesity-associated co-morbidities and technical factors. However, the true impact of obesity on postoperative outcomes is not well established and reports are conflicting. The aim was to perform a systematic review and meta-analysis to explore the effect of obesity on perioperative outcomes for general surgery procedures in distinct obesity subtypes.

METHODS

A systematic review was performed for studies reporting postoperative outcomes in relation to BMI in upper gastrointestinal, hepatobiliary and colorectal based on an electronic search using the Cochrane Library, Science Direct, PubMed and Embase up to January 2022. The primary outcome was the incidence of 30-day postoperative mortality among patients with obesity undergoing general surgical procedures in comparison to patients with normal range BMI.

RESULTS

Sixty-two studies, including 1 886 326 patients, were eligible for inclusion. Overall, patients with obesity (including class I/II/II) had lower 30-day mortality rates in comparison to patients with a normal BMI (odds ratio (OR) 0.75, 95 per cent c.i. 0.66 to 0.86, P < 0.0001, I2 = 71 per cent); this was also observed specifically in emergency general surgery (OR 0.83, 95 per cent c.i. 0.79 to 0.87, P < 0.0000001, I2 = 7 per cent). Compared with normal BMI, obesity was positively associated with an increased risk of 30-day postoperative morbidity (OR 1.11, 95 per cent c.i. 1.04 to 1.19, P = 0.002, I2 = 85 per cent). However, there was no significant difference in postoperative morbidity rates between the cohorts of patients with a normal BMI and class I/II obesity (OR 0.98, 95 per cent c.i. 0.92 to 1.04, P = 0.542, I2 = 92 per cent). Overall, the cohort with obesity had a higher rate of postoperative wound infections compared with the non-obese group (OR 1.40, 95 per cent c.i. 1.24 to 1.59, P < 0.0001, I2 = 82 per cent).

CONCLUSION

These data suggest a possible 'obesity paradox' and challenge the assumption that patients with obesity have higher postoperative mortality compared with patients with normal range BMI. Increased BMI alone is not associated with increased perioperative mortality in general surgery, highlighting the importance of more accurate body composition assessment, such as computed tomography anthropometrics, to support perioperative risk stratification and decision-making.

REGISTRATION NUMBER

CRD42022337442 (PROSPERO https://www.crd.york.ac.uk/prospero/).

Systematic review of groin wound surgical site infection incidence after arterial intervention

The objectives were to determine the surgical site infection incidence (including superficial/deep) fter arterial intervention through non-infected groin incisions and identify variables associated with incidence. MEDLINE, EMBASE and CENTRAL databases were searched for randomised controlled trials and observational studies of adults undergoing arterial intervention through a groin incision and reported surgical site infection. Infection incidence was examined in subgroups, variables were subjected to meta-regression. One hundred seventeen studies reporting 65 138 groin incisions in 42 347 patients were included. Overall surgical site infection incidence per incision was 8.1% (1730/21 431): 6.3% (804/12 786) were superficial and 1.9% (241/12 863) were deep. Superficial infection incidence was higher in randomised controlled trials (15.8% [278/1762]) compared with observational studies (4.8% [526/11 024]); deep infection incidence was similar (1.7% (30/1762) and 1.9% (211/11 101) respectively). Aneurysmal pathology (β = -10.229, P < .001) and retrospective observational design (β = -1.118, P = .002) were associated with lower infection incidence. Surgical site infection being a primary outcome was associated with a higher incidence of surgical site infections (β = 3.429, P = .017). The three-fold higher incidence of superficial surgical site infection reported in randomised controlled trials may be because of a more robust clinical review of patients. These results should be considered when benchmarking practice and could inform future trial design.

Assessment of Factors Associated with Morbidity and Textbook Outcomes of Laparoscopic Liver Resection in Obese Patients: A French Nationwide Study

BACKGROUND

Liver surgeons need to know the expected outcomes of laparoscopic liver resection (LLR) in obese patients.

OBJECTIVE

The purpose of the present study is to assess morbidity, mortality and textbook outcomes (TO) after LLR in obese patients.

METHODS

This is a French multicenter study of patients undergoing LLR between 1996 and 2018. Obesity was defined by a BMI at or above 30 kg/m 2 . Short-term outcomes and TO were compared between obese (ob) and nonobese (non-ob) patients. Factors associated with severe morbidity and TO were investigated.

RESULTS

Of 3,154 patients included, 616 (19.5%) were obese. Ob-group patients had significantly higher American Society of Anesthesiologists (ASA) score and higher incidence of metabolic syndrome and chronic liver disease and were less likely to undergo major hepatectomy. Mortality rates were similar between ob and non-ob groups (0.8 vs 1.1%; p = 0.66). Overall morbidity and hospital stay were significantly increased in the ob group compared with the non-ob group (39.4 vs 34.7%, p = 0.03; and 9.5 vs 8.6 days, p = 0.02), whereas severe 90-day morbidity (at or above Clavien-Dindo grade III) was similar between groups (8% in both groups; p = 0.90). TO rate was significantly lower for the ob group than the non-ob group (58.3 vs 63.7%; p = 0.01). In multivariate analysis, obesity did not emerge as a risk factor for severe 90-day morbidity but was associated with a lower TO rate after LLR (odds ratio = 0.8, 95% CI 0.7-1.0; p = 0.03).

CONCLUSIONS

LLR in obese patients is safe and effective with acceptable mortality and morbidity. Obesity had no impact on severe morbidity but was a factor for failing to achieve TO after LLR.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Comparison of the perioperative outcomes between robotic-assisted thoracic surgery and video-assisted thoracic surgery in non-small cell lung cancer patients with different body mass index ranges

Background

Non-small cell lung cancer (NSCLC) is the most common malignancy and one of the most common causes of cancer-related death worldwide. Robotic-assisted thoracic surgery (RATS) has gradually become a prevalent surgical method for patients with NSCLC. Previous studies have found that body mass index (BMI) is associated with postoperative outcomes. This study aimed to investigate the effectiveness of RATS compared to video-assisted thoracic surgery (VATS) in the treatment of NSCLC with different BMI, in terms of perioperative outcomes.

Methods

The baseline and perioperative data, including BMI, of 849 NSCLC patients who underwent minimally invasive anatomic lung resections from August 2020 to April 2021 were retrospectively collected and analyzed. Propensity score matching analysis was applied to minimize potential bias between the two groups (VATS and RATS), and the perioperative outcomes were compared. Subgroup analysis was subsequently performed.

Results

Compared to VATS, RATS had more lymph nodes dissected {9 [inter-quartile range (IQR), 6–12] vs. 7 (IQR, 6–10), P<0.001}, a lower estimated bleeding volume [40 (IQR, 30–50) vs. 50 (IQR, 40–60) mL, P<0.001], and other better postoperative outcomes, but a higher cost of hospitalization [¥83,626 (IQR, 77,211–92,686) vs. ¥75,804 (IQR, 66,184–83,693), P<0.001]. Multivariable logistic regression analysis indicated that RATS (P=0.027) and increasing BMI (P=0.030) were associated with a statistically significant reduction in the risk of postoperative complications. Subgroup analysis indicated that the advantages of RATS may be more obvious in patients with a BMI of 24–28 kg/m², in which the RATS group had more lymph nodes dissected [9 (IQR, 6–12) vs. 7 (IQR, 5–10), P<0.001] and a decreased risk of total postoperative complications [odds ratio (OR), 0.443; 95% confidence interval (CI), 0.212–0.924; P=0.030] compared to the VATS group.

Conclusions

Both, RATS and VATS can be safely applied for patients with NSCLC. Perioperative outcome parameters indicate advantages for RATS, however at a higher cost of hospitalization. The advantages of RATS might be more obvious in patients with a BMI of 24–28 kg/m².

The comparative and added prognostic value of biomarkers to the Revised Cardiac Risk Index for preoperative prediction of major adverse cardiac events and all-cause mortality in patients who undergo noncardiac surgery

BACKGROUND

The Revised Cardiac Risk Index (RCRI) is a widely acknowledged prognostic model to estimate preoperatively the probability of developing in-hospital major adverse cardiac events (MACE) in patients undergoing noncardiac surgery. However, the RCRI does not always make accurate predictions, so various studies have investigated whether biomarkers added to or compared with the RCRI could improve this.

OBJECTIVES

Primary: To investigate the added predictive value of biomarkers to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Secondary: To investigate the prognostic value of biomarkers compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Tertiary: To investigate the prognostic value of other prediction models compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery.

SEARCH METHODS

We searched MEDLINE and Embase from 1 January 1999 (the year that the RCRI was published) until 25 June 2020. We also searched ISI Web of Science and SCOPUS for articles referring to the original RCRI development study in that period.

SELECTION CRITERIA

We included studies among adults who underwent noncardiac surgery, reporting on (external) validation of the RCRI and: - the addition of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of the RCRI to other models. Besides MACE, all other adverse outcomes were considered for inclusion.

DATA COLLECTION AND ANALYSIS

We developed a data extraction form based on the CHARMS checklist. Independent pairs of authors screened references, extracted data and assessed risk of bias and concerns regarding applicability according to PROBAST. For biomarkers and prediction models that were added or compared to the RCRI in ≥ 3 different articles, we described study characteristics and findings in further detail. We did not apply GRADE as no guidance is available for prognostic model reviews.

MAIN RESULTS

We screened 3960 records and included 107 articles.   Over all objectives we rated risk of bias as high in ≥ 1 domain in 90% of included studies, particularly in the analysis domain. Statistical pooling or meta-analysis of reported results was impossible due to heterogeneity in various aspects: outcomes used, scale by which the biomarker was added/compared to the RCRI, prediction horizons and studied populations.  Added predictive value of biomarkers to the RCRI Fifty-one studies reported on the added value of biomarkers to the RCRI. Sixty-nine different predictors were identified derived from blood (29%), imaging (33%) or other sources (38%). Addition of NT-proBNP, troponin or their combination improved the RCRI for predicting MACE (median delta c-statistics: 0.08, 0.14 and 0.12 for NT-proBNP, troponin and their combination, respectively). The median total net reclassification index (NRI) was 0.16 and 0.74 after addition of troponin and NT-proBNP to the RCRI, respectively. Calibration was not reported. To predict myocardial infarction, the median delta c-statistic when NT-proBNP was added to the RCRI was 0.09, and 0.06 for prediction of all-cause mortality and MACE combined. For BNP and copeptin, data were not sufficient to provide results on their added predictive performance, for any of the outcomes. Comparison of the predictive value of biomarkers to the RCRI  Fifty-one studies assessed the predictive performance of biomarkers alone compared to the RCRI. We identified 60 unique predictors derived from blood (38%), imaging (30%) or other sources, such as the American Society of Anesthesiologists (ASA) classification (32%). Predictions were similar between the ASA classification and the RCRI for all studied outcomes. In studies different from those identified in objective 1, the median delta c-statistic was 0.15 and 0.12 in favour of  BNP and NT-proBNP alone, respectively, when compared to the RCRI, for the prediction of MACE. For C-reactive protein, the predictive performance was similar to the RCRI. For other biomarkers and outcomes, data were insufficient to provide summary results. One study reported on calibration and none on reclassification. Comparison of the predictive value of other prognostic models to the RCRI   Fifty-two articles compared the predictive ability of the RCRI to other prognostic models. Of these, 42% developed a new prediction model, 22% updated the RCRI, or another prediction model, and 37% validated an existing prediction model. None of the other prediction models showed better performance in predicting MACE than the RCRI. To predict myocardial infarction and cardiac arrest, ACS-NSQIP-MICA had a higher median delta c-statistic of 0.11 compared to the RCRI. To predict all-cause mortality, the median delta c-statistic was 0.15 higher in favour of ACS-NSQIP-SRS compared to the RCRI. Predictive performance was not better for CHADS2, CHA2DS2-VASc, R2CHADS2, Goldman index, Detsky index or VSG-CRI compared to the RCRI for any of the outcomes. Calibration and reclassification were reported in only one and three studies, respectively.

AUTHORS' CONCLUSIONS

Studies included in this review suggest that the predictive performance of the RCRI in predicting MACE is improved when NT-proBNP, troponin or their combination are added. Other studies indicate that BNP and NT-proBNP, when used in isolation, may even have a higher discriminative performance than the RCRI. There was insufficient evidence of a difference between the predictive accuracy of the RCRI and other prediction models in predicting MACE. However, ACS-NSQIP-MICA and ACS-NSQIP-SRS outperformed the RCRI in predicting myocardial infarction and cardiac arrest combined, and all-cause mortality, respectively. Nevertheless, the results cannot be interpreted as conclusive due to high risks of bias in a majority of papers, and pooling was impossible due to heterogeneity in outcomes, prediction horizons, biomarkers and studied populations. Future research on the added prognostic value of biomarkers to existing prediction models should focus on biomarkers with good predictive accuracy in other settings (e.g. diagnosis of myocardial infarction) and identification of biomarkers from omics data. They should be compared to novel biomarkers with so far insufficient evidence compared to established ones, including NT-proBNP or troponins. Adherence to recent guidance for prediction model studies (e.g. TRIPOD; PROBAST) and use of standardised outcome definitions in primary studies is highly recommended to facilitate systematic review and meta-analyses in the future.

Intra-operative nociceptive responses and postoperative major complications after gastrointestinal surgery under general anaesthesia: A prospective cohort study

BACKGROUND

Surgical procedures stimulate nociception and induce physiological responses according to the balance between nociception and antinociception. The severity of surgical stimuli is associated with major postoperative complications. Although an intra-operative quantitative index representing surgical invasiveness would be useful for anaesthetic management to predict and prevent major complications, no such index is available.

OBJECTIVES

To identify associations between major complications after gastrointestinal surgery and intra-operative quantitative values from intra-operative nociception monitoring.

DESIGN

A multi-institutional observational study.

SETTING

Two university hospitals.

PATIENTS

Consecutive adult patients undergoing gastrointestinal surgery under general anaesthesia.

MAIN OUTCOME MEASURES

Averaged values of nociceptive response index from start to end of surgery (mean NR index) and risk scores of the Surgical Mortality Probability Model (S-MPM) were calculated. Pre and postoperative serum C-reactive protein (CRP) levels were obtained. After receiver-operating characteristic (ROC) curve analysis, all patients were divided into groups with high and low mean nociceptive response index. Associations between mean nociceptive response index and postoperative major complications, defined as Clavien-Dindo grade at least IIIa, were examined using logistic regression analysis.

RESULTS

ROC curve analysis showed a nociceptive response index cut-off value for major complications of 0.83, and we divided patients into two groups with mean nociceptive response index less than 0.83 and at least 0.83. The incidence of major complications was significantly higher in patients with mean nociceptive response index at least 0.83 (23.1%; n = 346) than in patients with mean nociceptive response index less than 0.83 (7.7%; n = 443; P < 0.001). Multivariate analysis revealed emergency surgery, S-MPM risk score, mean nociceptive response index and postoperative CRP levels as independent risk factors for major complications.

CONCLUSION

Mean nociceptive response index during surgery likely correlates with major complications after gastrointestinal surgery.

TRIAL REGISTRATION

The current observational study had no intervention, and was therefore, not registered.

Impact of postoperative acute kidney injury in patients undergoing major gastrointestinal surgery on 1-year survival and renal outcomes: a national multicentre cohort study

BACKGROUND

The intermediate-term impact of acute kidney injury (AKI) in patients after major gastrointestinal and liver surgery has not been well characterized. This study aimed to evaluate the 1-year mortality rate and renal outcomes associated with postoperative AKI in a national prospective cohort.

METHODS

This prospective multicentre, observational cohort with 1-year postoperative follow-up included adults undergoing major gastrointestinal and liver surgery across the UK and Ireland between 23 September and 18 November 2015. AKI was defined according to Kidney Disease Improving Global Outcomes (KDIGO) criteria. The primary outcome was death at 1-year after surgery, and the secondary outcome was Major Adverse Kidney Events (MAKE-365). Cox proportionate and multilevel logistic regression were used to account for case mix.

RESULTS

Of 5745 patients across 173 centres, 1-year follow-up data was completed for 3504 patients (62.2 per cent, 126 centres), with attrition largely explained by centre non-participation (63.1 per cent). Some 13.6 per cent (475 of 3504) patients developed AKI by 7 days after surgery (stage 1: 9.2 per cent; stage 2/3: 4.3 per cent). At 1 year, 10.8 per cent (378 patients) experienced a MAKE-365 endpoint (303 patients had died, 61 had renal replacement therapy and 78 had renal dysfunction). Patients who experienced AKI by 7 days after surgery had a higher hazard of death at 1 year for KDIGO stage 1 (hazard ratio 1.50 (95 per cent c.i. 1.08 to 2.08), P = 0.016) and KDIGO stage 2/3 (hazard ratio 2.96 (95 per cent c.i. 2.02 to 4.33), P < 0.001). Both KDIGO stage 1 (odds ratio 2.09 (95 per cent c.i. 1.50 to 2.92), P < 0.001) and stage 2/3 (odds ratio 9.26 (95 per cent c.i. 6.31 to 13.59), P < 0.001) AKI were independently associated with MAKE-365.

CONCLUSION

AKI events within 7 days after gastrointestinal or liver surgery are associated with significantly worse survival and renal outcomes at 1 year.

Income Deprivation and Groin Wound Surgical Site Infection: Cross-Sectional Analysis from the Groin Wound Infection after Vascular Exposure Multicenter Cohort Study

Background: Living in deprived areas is associated with poorer outcomes after certain vascular procedures and surgical site infection in other specialties. Our primary objective was to determine whether living in more income-deprived areas was associated with groin wound surgical site infection after arterial intervention. Secondary objectives were to determine whether living in more income-deprived areas was associated with mortality and clinical consequences of surgical site infection. Methods: Postal code data for patients from the United Kingdom who were included in the Groin Wound Infection after Vascular Exposure (GIVE) multicenter cohort study was used to determine income deprivation, based on index of multiple deprivation (IMD) data. Patients were divided into three IMD groups for descriptive analysis. Income deprivation score was integrated into the final multivariable model for predicting surgical site infection. Results: Only patients from England had sufficient postal code data, analysis included 772 groin incisions (624 patients from 22 centers). Surgical site infection occurred in 9.7% incisions (10.3% of patients). Surgical site infection was equivalent between income deprivation tertiles (tertile 1 = 9.5%; tertile 2 = 10.3%; tertile 3 = 8.6%; p = 0.828) as were the clinical consequences of surgical site infection and mortality. Income deprivation was not associated with surgical site infection in multivariable regression analysis (odds ratio [OR], 0.574; 95% confidence interval [CI], 0.038-8.747; p = 0.689). Median age at time of procedure was lower for patients living in more income-deprived areas (tertile 1 = 68 years; tertile 2 = 72 years; tertile 3 = 74 years; p < 0.001). Conclusions: We found no association between living in an income-deprived area and groin wound surgical site infection, clinical consequences of surgical site infection and mortality after arterial intervention. Patients living in more income-deprived areas presented for operative intervention at a younger age, with similar rates of comorbidities to patients living in less income-deprived areas.

Association of Surgical Experience With Risk of Complication in Total Hip Arthroplasty Among Patients With Severe Obesity

IMPORTANCE

Severe obesity is a risk factor for major early complications after total hip arthroplasty (THA).

OBJECTIVE

To determine the association between surgeon experience with THA in patients with severe obesity and risk of complications.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective population-based cohort study was performed in Ontario, Canada, from April 1, 2007, to March 31, 2017, with data analysis performed from March 2020 to January 2021. A cohort of patients who received a primary THA for osteoarthritis and who also had severe obesity (body mass index [calculated as weight in kilograms divided by height in meters squared] ≥40) at the time of surgery was defined. These patients were identified using the Canadian Institute for Health Information Discharge Abstract Database and physician claims from the Ontario Health Insurance Plan. Generalized estimating equations were used to determine the association between overall THA and severe obesity-specific THA surgeon volume and the occurrence of complications after controlling for potential confounders. The study hypothesized that surgeon experience specific to patients with severe obesity could further reduce the risk of complications.

EXPOSURES

Primary THA.

MAIN OUTCOMES AND MEASURES

Complications were considered as a composite outcome (revision, infection requiring surgery, or dislocation requiring reduction), within 1 year of surgery. This was defined before the study, as was the study hypothesis.

RESULTS

A total of 4781 eligible patients was identified. The median age was 63 (interquartile range [IQR], 56-69) years, and 3050 patients (63.8%) were women. Overall, 186 patients (3.9%) experienced a surgical complication within 1 year of surgery. The median overall THA surgeon volume was 70 (IQR, 46-106) cases/y, whereas the median obesity-specific surgeon volume was 5 (IQR, 2-9) cases/y. After controlling for patient and hospital factors, greater obesity-specific THA surgeon volume (adjusted odds ratio per additional 10 cases, 0.65 [95% CI, 0.47-0.89]; P = .007), but not greater overall THA surgeon volume (adjusted odds ratio per 10 additional cases, 0.97 [95% CI, 0.93-1.02]; P = .24), was associated with a reduced risk of complication.

CONCLUSIONS AND RELEVANCE

Increased surgeon experience performing THA in patients with severe obesity was associated with fewer major surgical complications. These findings suggest that surgeon experience is required to mitigate the unique anatomical challenges posed by surgery in patients with severe obesity. Referral pathways for patients with severe obesity to surgeons with high obesity-specific THA volume should be considered.

Application effect of the principle of seamless management in nursing risk control of the department of gastrointestinal surgery

OBJECTIVE

To determine the application effect of nursing risk control based on the principle of seamless management in the department of gastrointestinal surgery.

METHODS

A total of 62 patients with gastrointestinal diseases admitted to the Department of Gastrointestinal Surgery in our hospital for nursing risk management based on the principle of seamless management were enrolled into a research group, and another 58 patients admitted before the implementation of such management were enrolled into a control group. The two groups were compared in the incidence of complications, Chinese Perceived Stress Scale (CPSS) score, self-rating anxiety scale (SAS) score, nursing satisfaction, and awareness rate of health knowledge, and the nursing quality scores and medical complaints and disputes were compared before and after the implementation of nursing risk control based on the principle of seamless management by 19 nurses in the department.

RESULTS

The pulmonary infection rate, incision infection rate, incidence of gastrointestinal reaction, and incidence of anastomotic leakage in the research group were all significantly lower than those in the control group (all P<0.05), and CPSS and SAS scores of the research group were also both significantly lower than those of the control group (both P<0.001). In addition, the research group showed significantly higher nursing satisfaction and awareness rate of health knowledge than the control group (both P<0.01), and there were notably less medical complaints and disputes after implementation of the principle of seamless management (P<0.01). Moreover, after implementation of the principle, nursing staff acquired significantly higher scores of professional skills (health education, professional knowledge, and practical operation; all P<0.001), and also contributed to significantly higher scores of nursing work (basic nursing, disinfection and isolation, ward management, intensive care, document writing, and nursing safety; all P<0.001).

CONCLUSION

Nursing risk control based on the principle of seamless management can improve the comprehensive quality of nursing staff in the department of gastrointestinal surgery and the overall quality of nursing, thus lowering the incidence of nursing risk, relieving patients' negative moods, and improving the nurse-patient relationship and satisfaction of both nurses and patients.

Optimizing Robotic Hysterectomy for the Patient Who Is Morbidly Obese with a Surgical Safety Pathway

STUDY OBJECTIVE

Obesity is a growing worldwide epidemic, and patients classified as obese undergoing gynecologic robotic surgery are at increased risk for surgical complications. This study aimed to evaluate the feasibility and outcomes of a surgical safety protocol known as the High BMI [Body Mass Index] Pathway (HBP) for patients with BMI ≥40 kg/m² undergoing planned robotic hysterectomy. Our primary outcome was the rate of all-cause perioperative complications in patients undergoing surgery with the use of the HBP.

DESIGN

A retrospective cohort study.

SETTING

An academic teaching hospital.

PATIENTS

A total of 138 patients classified as morbidly obese (BMI ≥40 kg/m²) undergoing robotic hysterectomy.

INTERVENTIONS

The HBP was developed by a multidisciplinary team and was instituted on January 1, 2016, as a quality improvement project. Patients classified as morbidly obese undergoing robotic hysterectomy after this date were compared with consecutive historical controls.

MEASUREMENTS AND MAIN RESULTS

Seventy-two patients underwent robotic hysterectomies on the HBP and were compared with 66 controls. There were no differences in age, BMI, blood loss, number of comorbidities, or cancer diagnosis. Since the implementation of the HBP, there has been a decrease in anesthesia time (-57.0 minutes; p = .001) and total operating room time (-47.0 min; p = .020), as well as lower estimated blood loss (median 150 mL [interquartile range 100-200] vs 200 mL [interquartile range 100-300]; p = .002) and reduction in overnight hospital admissions (33.3% vs 63.6%; p <.001). In the HBP group, there were fewer all-cause complications (19.4% vs 37.9%; p = .023) and infectious complications (8.3% vs 33.3%; p = .001), and there was no increase in the readmission rates (p = .400). In multivariable analysis, the HBP reduced all-cause complications (odds ratio 0.353; p = .010) after controlling for the covariate (total time in the operating room).

CONCLUSION

The HBP is a feasible method of optimizing the outcome for patients classified as morbidly obese undergoing major gynecologic surgery. Initiation of the HBP can lead to decreased anesthesia and operating times, all-cause complications, and overnight hospital admissions without increasing readmission rates.

Groin wound Infection after Vascular Exposure (GIVE) Study Group. Groin wound infection after vascular exposure (GIVE) multicentre cohort study

Surgical site infections (SSIs) of groin wounds are a common and potentially preventable cause of morbidity, mortality, and healthcare costs in vascular surgery. Our aim was to define the contemporaneous rate of groin SSIs, determine clinical sequelae, and identify risk factors for SSI. An international multicentre prospective observational cohort study of consecutive patients undergoing groin incision for femoral vessel access in vascular surgery was undertaken over 3 months, follow-up was 90 days. The primary outcome was the incidence of groin wound SSI. 1337 groin incisions (1039 patients) from 37 centres were included. 115 groin incisions (8.6%) developed SSI, of which 62 (4.6%) were superficial. Patients who developed an SSI had a significantly longer length of hospital stay (6 versus 5 days, P = .005), a significantly higher rate of post-operative acute kidney injury (19.6% versus 11.7%, P = .018), with no significant difference in 90-day mortality. Female sex, Body mass index≥30 kg/m2 , ischaemic heart disease, aqueous betadine skin preparation, bypass/patch use (vein, xenograft, or prosthetic), and increased operative time were independent predictors of SSI. Groin infections, which are clinically apparent to the treating vascular unit, are frequent and their development carries significant clinical sequelae. Risk factors include modifiable and non-modifiable variables.

Mihaljevic AL. Multicenter Prospective Cohort Study of the Patient-Reported Outcome Measures PRO-CTCAE and CAT EORTC QLQ-C30 in Major Abdominal Cancer Surgery (PATRONUS): A Student-Initiated German Medical Audit (SIGMA) Study

Background

The patient-reported outcomes (PRO) version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) and the computerized adaptive testing (CAT) version of the EORTC quality-of-life questionnaire QLQ-C30 have been proposed as new PRO measures in oncology; however, their implementation in patients undergoing cancer surgery has not yet been evaluated.

Methods

Patients undergoing elective abdominal cancer surgery were enrolled in a prospective multicenter study, and postoperative complications were recorded according to the Dindo–Clavien classification. Patients reported PRO data using the CAT EORTC QLQ-C30 and the PRO-CTCAE to measure 12 core cancer symptoms. Patients were followed-up for 6 months postoperatively. The study was carried out by medical students of the CHIR-Net SIGMA study network.

Results

Data of 303 patients were obtained and analyzed across 15 sites. PRO-CTCAE symptoms ‘poor appetite’, ‘fatigue’, ‘exhaustion’ and ‘sleeping problems’ increased after surgery and climaxed 10–30 days postoperatively. At 3–6 months postoperatively, no PRO-CTCAE symptom differed significantly to baseline. Patients reported higher ‘social functioning’ (p = 0.021) and overall quality-of-life scores (p < 0.05) 6 months after cancer surgery compared with the baseline level. There was a lack of correlation between postoperative complications or death and any of the PRO items evaluated. Feasibility endpoints for student-led research were met.

Conclusion

The two novel PRO questionnaires were successfully applied in surgical oncology. Postoperative complications do not affect health-reported quality-of-life or common cancer symptoms following major cancer surgery. The feasibility of student-led multicenter clinical research was demonstrated, but might be enhanced by improved student training.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-021-09646-z.

Impact of Smoking Status on Perioperative Morbidity, Mortality, and Long-Term Survival Following Transthoracic Esophagectomy for Esophageal Cancer

Introduction

Esophagectomy is a key component in the curative treatment of esophageal cancer. Little is understood about the impact of smoking status on perioperative morbidity and mortality and the long-term outcome of patients following esophagectomy.

Objective

This study aimed to evaluate morbidity and mortality according to smoking status in patients undergoing esophagectomy for esophageal cancer.

Methods

Consecutive patients undergoing two-stage transthoracic esophagectomy (TTE) for esophageal cancers (adenocarcinoma or squamous cell carcinoma) between January 1997 and December 2016 at the Northern Oesophagogastric Unit were included from a prospectively maintained database. The main explanatory variable was smoking status, defined as current smoker, ex-smoker, and non-smoker. The primary outcome was overall survival (OS), while secondary outcomes included perioperative complications (overall, anastomotic leaks, and pulmonary complications) and survival (cancer-specific survival [CSS], recurrence-free survival [RFS]).

Results

During the study period, 1168 patients underwent esophagectomy for cancer. Of these, 24% (n = 282) were current smokers and only 30% (n = 356) had never smoked. The median OS of current smokers was significantly shorter than ex-smokers and non-smokers (median 36 vs. 42 vs. 48 months; p = 0.015). However, on adjusted analysis, there was no significant difference in long-term OS between smoking status in the entire cohort. The overall complication rates were significantly higher with current smokers compared with ex-smokers or non-smokers (73% vs. 66% vs. 62%; p = 0.018), and there were no significant differences in anastomotic leaks and pulmonary complications between the groups. On subgroup analysis by receipt of neoadjuvant therapy and tumor histology, smoking status did not impact long-term survival in adjusted multivariable analyses.

Conclusion

Although smoking is associated with higher rates of short-term perioperative morbidity, it does not affect long-term OS, CSS, and RFS following esophagectomy for esophageal cancer. Therefore, implementation of perioperative pathways to optimize patients may help reduce the risk of complications.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-021-09720-6.

Incidence and risk factors of postoperative complications after robotic gastrectomy for gastric cancer: an analysis of 817 cases based on 10-year experience in a large-scale center

BACKGROUND

In this study, we investigated the incidence and risk factors for postoperative complications after robotic gastrectomy (RG) in patients with gastric cancer.

METHODS

A total of 817 patients who underwent RG for gastric cancer between March 2010 and August 2019 were analyzed retrospectively. Postoperative complications were categorized according to the Clavien-Dindo classification, and possible risk factors were evaluated.

RESULTS

Among 817 patients who underwent RG, overall, severe, local and systemic complication rates were 13.8, 4.2, 7.0 and 6.9%, respectively. Multivariable analysis revealed that an age of 70 years or older (P < 0.001) and multiorgan resection (P = 0.031) were independent risk factors for the occurrence of overall complications. Multivariable analysis showed that an age of 70 years or older (P = 0.005) and surgeons' experience ≤ 25 cases (P = 0.004) were independent risk factors for severe complications. Regarding local complications, an age of 70 years or older (P < 0.001), multiorgan resection (P = 0.010) and surgeons' experience ≤ 25 cases (P = 0.005) were identified as independent risk factors. An age of 70 years or older (P < 0.001), a BMI of 25 or higher (P = 0.045) and the presence of comorbidity (P = 0.029) were identified as independent risk factors for systemic complications.

CONCLUSIONS

The present study demonstrated that RG is a safe and feasible procedure for the treatment of gastric cancer, and it has an acceptable postoperative morbidity. Elderly patients and insufficient surgeon experience were two major risk factors for the occurrence of complications following RG. We suggest that surgeons choose patients in good condition during their RG learning phase to reduce learning-associated morbidity.

The Association between Body Composition Measurements and Surgical Complications after Living Kidney Donation

Obesity is considered a risk factor for peri- and postoperative complications. Little is known about this risk in overweight living kidney donors. The aim of this study was to assess if anthropometric body measures and/or surgical determinants are associated with an increased incidence of peri- and postoperative complications after nephrectomy. We included 776 living kidney donors who donated between 2008 and 2018 at the University Medical Center Groningen. Prenephrectomy measures of body composition were body mass index (BMI), body surface area (BSA), waist circumference, weight, and waist-hip ratio. Incidence and severity of peri- and postoperative complications were assessed using the Comprehensive Complication Index. Mean donor age was 53 ± 11 years; 382 (49%) were male, and mean BMI at donor screening was 26.2 ± 3.41 kg/m2. In total, 77 donors (10%) experienced peri- and postoperative complications following donor nephrectomy. Male sex was significantly associated with fewer surgical complications (OR 0.59, 0.37-0.96 95%CI, p = 0.03) in binomial logistic regression analyses. Older age (OR: 1.03, 1.01-1.05 95%CI, p = 0.02) and a longer duration of surgery (OR: 1.01, 1.00-1.01 95%CI, p = 0.02) were significantly associated with more surgical complications in binomial logistic regression analyses. Multinomial logistic regression analyses did not identify any prenephrectomy measure of body composition associated with a higher risk of surgical complications. This study shows that higher prenephrectomy BMI and other anthropometric measures of body composition are not significantly associated with peri- and postoperative complications following living donor nephrectomy.

Preoperative communication between anaesthetists and patients with obesity regarding perioperative risks and weight management: a structured narrative review

BACKGROUND

Individuals with obesity frequently present for anaesthesia and surgery. Good communication during the preoperative consultation can optimise the provision of relevant health information and guide improvement of health status preoperatively.

METHODS

We planned a systematic literature review to assess existing guidelines and evidence of effectiveness for how anaesthetists should communicate with patients who have obesity in the preoperative period about perioperative risks and weight management. Database searches used keywords related to perioperative weight loss conversations. We found no papers that directly addressed our aim. The literature identified as most relevant was analysed in the form of a narrative review.

RESULTS

The majority of suggestions for weight loss conversations came from primary care. Four primary themes potentially relevant to anaesthetists were identified: barriers to such conversations, communication tools, language and communication and specific recommendations. Identified barriers included lack of skills, training, poor remuneration, pessimism and time constraints for clinicians. Established discussion tools including the '5A's' approach (Assess, Advise, Agree, Assist, Arrange) and motivational interviewing may hold promise to improve preoperative conversations. The papers highlighted a need for empathetic language, including use of patient-specific language where possible.

CONCLUSIONS

There are currently no published guidelines for how anaesthetists could most effectively discuss weight in the perioperative period with patients who have obesity. Much of the literature for obesity communication is based on the primary care setting. The perioperative period may represent an increased time of receptiveness for patients. Guidelines for discussions about weight management and associated perioperative risk are suggested.

Morbidity and short-term surgical outcomes of robotic versus laparoscopic distal gastrectomy for gastric cancer: a large cohort study

BACKGROUND

Robotic distal gastrectomy (RDG) has been increasingly used for the treatment of gastric cancer in recent year. However, whether RDG could reduce the morbidity when compared to laparoscopic distal gastrectomy (LDG) remains controversial. This study aimed to compare the morbidity and short-term surgical outcomes of RDG and LDG for gastric cancer and identify the related risk factors.

METHODS

Between March 2010 and August 2019, consecutive patients undergoing RDG or LDG (519 and 957 patients, respectively) at our institution were included in this study. Postoperative complications were stratified according to the Clavien-Dindo (C-D) classification. We performed one-to-one propensity score matching (PSM) analysis, and evaluated postoperative morbidity and short-term surgical outcomes in PSM 1032 patients undergoing RDG or LDG.

RESULTS

After PSM, the two groups were well-balanced. The mean blood loss of the RDG group was about 27 mL less than that of the LDG group (112.1 vs 139.0 mL, P < 0.001). The RDG group had more retrieved lymph nodes than that in the LDG group (32.7 v 30.2, P < 0.001). The RDG group showed a similar overall (9.9% vs 10.7%, P = 0.682), severe (2.7% vs 3.7%, P = 0.376), local (5.6% vs 5.2%, P = 0.783), and systemic complication rates (5.4% vs 6.0%, P = 0.688). There were no significant differences in mortality between the two groups (RDG 0% vs LDG 0.2%, P = 1.000). Subgroup analyses showed no significant differences in most stratified parameters. Age > 65 years and ASA III were identified as two major risk factors for complications.

CONCLUSION

RDG could be a safe and feasible in treating gastric cancer compared to LDG. However, we did not observe significant reduction in postoperative complications of RDG compared with LDG, although the use of robotic system is assumed to provide a technically superior operative environment.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Obesity and Cancer Treatment Outcomes: Interpreting the Complex Evidence

A wealth of epidemiological evidence, combined with plausible biological mechanisms, present a convincing argument for a causal relationship between excess adiposity, commonly approximated as body mass index (BMI, kg/m²), and incident cancer risk. Beyond this relationship, there are a number of challenges posed in the context of interpreting whether being overweight (BMI 25.0-29.9 kg/m²) or obese (BMI ≥ 30.0 kg/m²) adversely influences disease progression, cancer mortality and survival. Elevated BMI (≥ 25.0 kg/m²) may influence treatment selection of, for example, the approach to surgery; the choice of chemotherapy dosing; the inclusion of patients into randomised clinical trials. Furthermore, the technical challenges posed by an elevated BMI may adversely affect surgical outcomes, for example, morbidity (increasing the risk of surgical site infections), reduced lymph node harvest (and subsequent risk of under-staging and under-treatment) and increased risk of margin positivity. Suboptimal chemotherapy dosing, associated with capping chemotherapy in obese patients as an attempt to avoid excess toxicity, might be a driver of poor prognostic outcomes. By contrast, the efficacy of immune checkpoint inhibition may be enhanced in patients who are obese, although in turn, this observation might be due to reverse causality. So, a central research question is whether being overweight or obese adversely affects outcomes either directly through effects of cancer biology or whether adverse outcomes are mediated through indirect pathways. A further dimension to this complex relationship is the obesity paradox, a phenomenon where being overweight or obese is associated with improved survival where the reverse is expected. In this overview, we describe a framework for evaluating methodological problems such as selection bias, confounding and reverse causality, which may contribute to spurious interpretations. Future studies will need to focus on prospective studies with well-considered methodology in order to improve the interpretation of causality.

Nutritional status and its effect on complications in patients with colorectal cancer

BACKGROUND

Nutritional status is an important factor for predicting the risk of developing complications after a surgical procedure. Many nutritional assessments are used in clinical practice, but their role in predicting postoperative outcomes is unknown. Therefore, the aim of this study was to assess the utility of nutritional risk factors at the diagnosis of colorectal cancer (CRC) for predicting early postsurgical complications.

METHODS

This was a prospective observational study including 127 patients with CRC at diagnosis. Their preoperative nutritional status was analyzed by body mass index (BMI), triceps and subscapular skinfolds and two nutritional scales: the Patient-Generated Subjective Global Assessment (PG-SGA) and the Malnutrition Universal Screening Tool (MUST). The outcome variables, including postoperative complications, length of hospital stay and mortality, were analyzed.

RESULTS

Patients identified as malnourished by PG-SGA score had prolonged hospital stays (p = 0.01). The risk of infection was increased in older patients (hazard ratio, HR 1.12; 95% confidence interval, CI 1.04-1.21) but was not associated with nutritional status. Early wound dehiscence was increased in patients with higher BMI (HR 1.15; 95% CI 1.01-1.29), with higher subscapular skinfold thickness and increased age (HR 1.05; 95% CI 1.05-1.10). Postoperative mortality was not significantly associated with nutritional status.

CONCLUSION

Malnourished patients, as identified by the PG-SGA score, stayed longer in hospital than patients who were not malnourished, while increased BMI was recognized as a risk factor for wound dehiscence.

Comparison of Outcomes between Obese and Non-Obese Patients in a Colorectal Enhanced Recovery After Surgery (ERAS) Program: A Single-Center Cohort Study

INTRODUCTION

Obese patients are considered at increased risk of postoperative adverse events after colorectal surgery.

OBJECTIVE

The objective of the present study was to compare postoperative outcomes between obese and non-obese patients undergoing elective colorectal surgery in an Enhanced Recovery After Surgery (ERAS) program.

METHODS

A retrospective analysis of a prospective cohort including patients who underwent elective colorectal surgery and were included in an ERAS protocol between February 2014 and December 2017 at Geneva University Hospital, Geneva, Switzerland, was performed. Postoperative outcomes of obese and non-obese patients were compared.

RESULTS

Data of 460 patients were analyzed, including 374 (81%) non-obese and 86 (19%) obese patients. Overall, there was no difference in postoperative outcomes between the 2 groups. Among patients undergoing oncologic surgery, obese subjects had a significantly higher rate of conversion to laparotomy (11.9 vs. 2.1%, p = 0.01) and longer time until return of bowel function (2.38 vs. 1.98 days, p = 0.03), without increased morbidity or longer length of stay.

CONCLUSION

Obese and non-obese patients had similar postoperative outcomes after elective colorectal surgery with ERAS management. ERAS can potentially reduce the increased morbidity usually observed in obese patients following elective colorectal surgery.

Postoperative complications and mobilisation following major abdominal surgery with vs. without fitness tracker-based feedback (EXPELLIARMUS): study protocol for a student-led multicentre randomised controlled trial (CHIR-Net SIGMA study group)

BACKGROUND

Postoperative complications following major abdominal surgery are frequent despite progress in surgical technique and perioperative care. Early and enhanced postoperative mobilisation has been advocated to reduce postoperative complications, but it is still unknown whether it can independently improve outcomes after major surgery. Fitness trackers (FTs) are a promising tool to improve postoperative mobilisation, but their effect on postoperative complications and recovery has not been investigated in clinical trials.

METHODS

This is a multicentre randomised controlled trial with two parallel study groups evaluating the efficacy of an enhanced and early mobilisation protocol in combination with FT-based feedback in patients undergoing elective major abdominal surgery. Participants are randomly assigned (1:1) to either the experimental group, which receives daily step goals and a FT giving feedback about daily steps, or the control group, which is mobilised according to hospital standards. The control group also receives a FT, however with a blackened screen; thus no FT-based feedback is possible. Randomisation will be stratified by type of surgery (laparoscopic vs. open). The primary endpoint of the study is postoperative morbidity within 30 days measured via the Comprehensive Complication Index. Secondary endpoints include number of steps as well as a set of functional, morbidity and safety parameters. A total of 348 patients will be recruited in 15 German centres. The study will be conducted and organised by the student-led German Clinical Trial Network SIGMA.

DISCUSSION

Our study aims at investigating whether the implementation of a simple mobilisation protocol in combination with FT-based feedback can reduce postoperative morbidity in patients undergoing major abdominal surgery. If so, FTs would offer a cost-effective intervention to enhance postoperative mobilisation and improve patient outcomes.

TRIAL REGISTRATION

Deutsches Register Klinischer Studien (DRKS, German Clinical Trials Register): DRKS00016755, UTN U1111-1228-3320. Registered on 06.03.2019.

Reverse puncture device technique: an innovation of esophagojejunostomy in radical laparoscopic total gastrectomy

Aim: To evaluate the feasibility, safety, short- and long-term efficacy of a reverse puncture device (RPD) technique for esophagojejunostomy in laparoscopic-assisted total gastrectomy. Patients & methods: This retrospective study analyzed outcome data of 104 patients in propensity score matching whom were divided into the RPD and the purse-string suture technique group. Results: The RPD group had a shorter anvil placement time, shorter operative time, longer resected esophageal length, shorter incision length, shorter postoperative drainage time, shorter postoperative hospital stay and anastomotic complications than the purse-string suture technique group (p < 0.05). Multivariate analysis showed that BMI (odds ratio: 6.285, 1.446-27.322) and anvil placement time (odds ratio: 5.645, 1.089-29.321) were independent risk factors for anastomotic complications (p < 0.05). Conclusion: Laparoscopic-assisted total gastrectomy using an RPD technique is feasible, safe and effective.

Association between intraoperative nociception and postoperative complications in patients undergoing laparoscopic gastrointestinal surgery

A higher degree of surgical invasiveness, which increases intraoperative nociception, might induce postoperative complications. Although several nociceptive indices for use during surgery are available in clinical practice, association between intraoperative nociception and postoperative complications has not been reported. An index representing intraoperative nociception, which is the averaged value of Nociceptive Response throughout the surgery (mean NR) was applied to examine the association in the present study. The retrospective study evaluated consecutive adult patients undergoing laparoscopic gastrointestinal surgery, American Society of Anesthesiologists-physical status (ASA-PS) I or II, whose preoperative C-reactive protein level was < 0.3 mg dL^-1. We first used ordinal logistic analysis to examine the association between preoperative and intraoperative risk factors and complications graded by the Clavien-Dindo classification. Next, we performed propensity score matched analysis to evaluate the effects of mean NR throughout surgery on postoperative complications. Ordinal logistic analysis (n = 158) revealed that duration of surgery (P < 0.001), mean NR during surgery (P = 0.002), and ASA-PS (P = 0.016) were risk factors for postoperative complications. Then all patients were divided into two propensity score matched groups, based on a mean NR of < 0.85 and ≥ 0.85, with matching for age, ASA-PS, body mass index and duration of surgery. The severity of postoperative complications was significantly higher in the high NR group than in the low NR group (P = 0.005). In conclusion, there was likely an association between intraoperative nociception and postoperative complications in patients without serious preoperative conditions and comorbidities.

Challenging traditional research: A synopsis of the National Research Collaborative Meeting (NRCM) in 2017

INTRODUCTION

The National Research Collaborative Meeting (NRCM) 2017 was jointly hosted between the West Midlands Research Collaborative (WMRC) and Student Audit and Research in Surgery (STARSurg) on 30th November 2017 in Birmingham. The NRCM 2017 theme was 'Challenging Traditional Research'.

METHODS

Narrative review, outlining key challenges and recommendations for trainee collaborative research groups across medical and surgical disciplines based on the core themes from the NRCM 2017 meeting.

RESULTS

Core themes of: (1) surgical oncology trials; (2) placebo-controlled surgical trials; (3) research funding; (4) medical student involvement in research; (5) emergency care; (6) patient and public involvement. Recommendations were made for planning future collaborative studies, based on these topic areas.

CONCLUSIONS

The collaborative research model has demonstrated longevity and effectiveness in delivering high-quality, practice-changing research both within the NHS and internationally. Learning between groups and highlighting areas for interdisciplinary collaboration will drive a meaningful, patient-centred agenda for the future.

Oncologic evaluation of obesity as a factor in patients with rectal cancer undergoing laparoscopic surgery: a propensity-matched analysis using body mass index

Purpose

This study evaluated the oncologic impact of obesity, as determined by body mass index (BMI), in patients who underwent laparoscopic surgery for rectal cancer.

Methods

The records of 483 patients with stage I-III rectal cancer who underwent laparoscopic surgery between June 2003 and December 2011 were reviewed. A matching model based on BMI was constructed to balance obese and nonobese patients. Cox hazard regression models for overall survival (OS) and disease-free survival (DFS) were used for multivariate analyses. Additional analysis using visceral fat area (VFA) measurement was performed for matched patients. The threshold for obesity was BMI ≥ 25 kg/m² or VFA ≥ 130 cm².

Results

The score matching model yielded 119 patients with a BMI ≥ 25 kg/m² (the obese group) and 119 patients with a BMI < 25 kg/m² (the nonobese group). Surgical outcomes including operation time, estimated blood loss, nil per os periods, and length of hospital stay did not differ between the obese and the nonobese group. The retrieved lymph node numbers and pathologic CRM positive rate were also similar in between the 2 groups. After a median follow-up of 48 months (range, 3-126 months), OS and DFS rates were similar between the 2 groups. A tumor location-adjusted model for overall surgical complications showed that a BMI ≥ 25 kg/m² were not risk factors. Multivariable analyses for OS and DFS showed no significant association with a BMI ≥ 25 kg/m².

Conclusion

Obesity was not associated with long-term oncologic outcomes in patients undergoing laparoscopic surgery for rectal cancer in the Asian population.

Attitudes to out-of-programme experiences, research and academic training of gastroenterology trainees between 2007 and 2016

OBJECTIVE

Academic medical training was overhauled in 2005 after the Walport report and Modernising Medical Careers to create a more attractive and transparent training pathway. In 2007 and 2016, national web-based surveys of gastroenterology trainees were undertaken to determine experiences, perceptions of and perceived barriers to out-of-programme research experience (OOP-R).

DESIGN SETTING AND PATIENTS

Prospective, national web-based surveys of UK gastroenterology trainees in 2007 and 2016.

MAIN OUTCOME MEASURE

Attitudes to OOP-R of two cohorts of gastroenterology trainees.

RESULTS

Response rates were lower in 2016 (25.8% vs 56.7%) (p<0.0001), although female trainees' response rates increased (from 28.8% to 37.6%) (p=0.17), along with higher numbers of academic trainees. Over 80% of trainees planned to undertake OOP-R in both surveys, with >50% having already undertaken it. Doctor of Philosophy/medical doctorate remained the most popular OOP-R in both cohorts. Successful fellowship applications increased in 2016, and evidence of gender inequality in 2007 was no longer evident in 2016. In the 2016 cohort, 91.1% (n=144) felt the development of trainee-led research networks was important, with 74.7% (n=118) keen to get involved.

CONCLUSIONS

The majority of gastroenterology trainees who responded expressed a desire to undertake OOP-R, and participation rates in OOP-R remain high. Despite smaller absolute numbers responding than in 2007, 2016 trainees achieved higher successful fellowship application rates. Reassuringly more trainees in 2016 felt that OOP-R would be important in the future. Efforts are needed to tackle potential barriers to OOP-R and support trainees to pursue research-active careers.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Relevante Nebenerkrankungen zu Notfallindikationen und Notfalloperationen in der Viszeral- und Allgemeinchirurgie

Die Adipositas ist eine über das Normalmaß hinausgehende Vermehrung des Körperfetts und wird über den Body-Mass- Index (BMI = kg/m) bestimmt. Ab einem BMI von 30 kg/m liegt definitionsgemäß eine Adipositas vor. Der Krankheitswert ergibt sich aus der Assoziation von Folgeerkrankungen, deren Risiko mit der Prävalenzdauer und dem Schweregrad der Adipositas ansteigt (Tab. 28.1). Dabei korreliert das kardiovaskuläre Risiko besonders mit dem Vorliegen einer viszeralen Adipositas (>88/102 cm Taillenumfang bei Frauen/ Männern). Die Prävalenz der Adipositas steigt in Deutschland kontinuierlich an. Derzeit ist knapp ein Viertel der deutschen Bevölkerung als adipös einzustufen.

STARSurg Collaborative. Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study

BACKGROUND

Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery.

METHODS

This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation.

RESULTS

A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65).

DISCUSSION

Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability.

Predictors of complications and mortality following left colectomy with primary stapled anastomosis for cancer: results of a multicentric study with 1111 patients

AIM

Reports detailing the morbidity-mortality after left colectomy are sparse and do not allow definitive conclusions to be drawn. We aimed to identify risk factors for anastomotic leakage, perioperative mortality and complications following left colectomy for colonic malignancies.

METHOD

We undertook a STROBE-compliant analysis of left colectomies included in a national prospective online database. Forty-two variables were analysed as potential independent risk factors for anastomotic leakage, postoperative morbidity and mortality. Variables were selected using the 'least absolute shrinkage and selection operator' (LASSO) method.

RESULTS

We analysed 1111 patients. Eight per cent of patients had a leakage and in 80% of them reoperation or surgical drainage was needed. A quarter of patients (24.9%) experienced at least one minor complication. Perioperative mortality was 2%, leakage being responsible for 47.6% of deaths. Obesity (OR 2.8, 95% CI 1.00-7.05, P = 0.04) and total parenteral nutrition (TPN) (OR 3.7, 95% CI 1.58-8.51, P = 0.002) were associated with increased risk of leakage, whereas female patients had a lower risk (OR 0.36, 95% CI 0.18-0.67, P = 0.002). Corticosteroids (P = 0.03) and oral anticoagulants (P = 0.01) doubled the risk of complications, which was lower with hyperlipidaemia (OR 0.3, P = 0.02). Patients on TPN had more complications (OR 4.02, 95% CI 2.03-8.07, P = 0.04) and higher mortality (OR 8.7, 95% CI 1.8-40.9, P = 0.006). Liver disease and advanced age impaired survival, corticosteroids being the strongest predictor of mortality (OR 21.5, P = 0.001).

CONCLUSION

Requirement for TPN was associated with more leaks, complications and mortality. Leakage was presumably responsible for almost half of deaths. Hyperlipidaemia and female gender were associated with lower rates of complications. These findings warrant a better understanding of metabolic status on perioperative outcome after left colectomy.

Prospective multicentre cohort study of patient-reported outcomes and complications following major abdominal neoplastic surgery (PATRONUS) - study protocol for a CHIR-Net student-initiated German medical audit study (CHIR-Net SIGMA study)

BACKGROUND

One of the most important aspects of designing a clinical trial is selecting appropriate outcomes. Patient-reported outcomes (PROs) can provide a personal assessment of the burden and impact of a malignant disease and its treatment. PROs comprise a wide range of outcomes including basic clinical symptom scores and complex metrics such as health-related quality of life (HRQoL). There is limited data on how postoperative complications following cancer surgery affect symptoms and HRQoL. For this reason the primary aim of the PATRONUS study is to investigate how perioperative complications affect cancer-related symptoms and HRQoL in patients undergoing abdominal cancer surgery. The PATRONUS study is designed and will be initiated and conducted by medical students under the direct supervision of clinician scientists based on the concept of inquiry-based learning.

METHODS

PATRONUS is a non-interventional prospective multicentre cohort study. Patients undergoing elective oncological abdominal surgery will be recruited at regional centres of the clinical network of the German Surgical Society (CHIR-Net) and associated hospitals. A core set of 12 cancer associated symptoms will be assessed via the PRO version of the Common Terminology Criteria for Adverse Events. The cancer-specific HRQoL will be measured via the computerised adaptive testing version of the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30. PROs will be measured eight times over a period of six months. The short-term clinical outcome measure is the rate of postoperative complications (grade II to V) within 30 days according to the Clavien-Dindo classification. The long-term clinical outcome is overall survival within six months postoperative.

DISCUSSION

PATRONUS will provide essential insights into the patients' assessment of their well-being and quality of life in direct relation to clinical outcome parameters following abdominal cancer surgery. Furthermore, PATRONUS will investigate the feasibility of multicentre student-led clinical research.

TRIAL REGISTRATION

German Clinical Trials Register: DRKS00013035 (registered on October 26, 2017). Universal Trial Number (UTN): U1111-1202-8863.

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.

The 2017 European Society of Coloproctology (ESCP) collaborating group. Association of mechanical bowel preparation with oral antibiotics and anastomotic leak following left sided colorectal resection: an international, multi-centre, prospective audit

INTRODUCTION

The optimal bowel preparation strategy to minimise the risk of anastomotic leak is yet to be determined. This study aimed to determine whether oral antibiotics combined with mechanical bowel preparation (MBP+Abx) was associated with a reduced risk of anastomotic leak when compared to mechanical bowel preparation alone (MBP) or no bowel preparation (NBP).

METHODS

A pre-planned analysis of the European Society of Coloproctology (ESCP) 2017 Left Sided Colorectal Resection audit was performed. Patients undergoing elective left sided colonic or rectal resection with primary anastomosis between 1 January 2017 and 15 March 2017 by any operative approach were included. The primary outcome measure was anastomotic leak.

RESULTS

Of 3676 patients across 343 centres in 47 countries, 618 (16.8%) received MBP+ABx, 1945 MBP (52.9%) and 1099 patients NBP (29.9%). Patients undergoing MBP+ABx had the lowest overall rate of anastomotic leak (6.1%, 9.2%, 8.7% respectively) in unadjusted analysis. After case-mix adjustment using a mixed-effects multivariable regression model, MBP+Abx was associated with a lower risk of anastomotic leak (OR 0.52, 0.30-0.92, P = 0.02) but MBP was not (OR 0.92, 0.63-1.36, P = 0.69) compared to NBP.

CONCLUSION

This non-randomised study adds 'real-world', contemporaneous, and prospective evidence of the beneficial effects of combined mechanical bowel preparation and oral antibiotics in the prevention of anastomotic leak following left sided colorectal resection across diverse settings. We have also demonstrated limited uptake of this strategy in current international colorectal practice.

EuroSurg Collaborative. Body mass index and complications following major gastrointestinal surgery: a prospective, international cohort study and meta-analysis

AIM

Previous studies reported conflicting evidence on the effects of obesity on outcomes after gastrointestinal surgery. The aims of this study were to explore the relationship of obesity with major postoperative complications in an international cohort and to present a meta-analysis of all available prospective data.

METHODS

This prospective, multicentre study included adults undergoing both elective and emergency gastrointestinal resection, reversal of stoma or formation of stoma. The primary end-point was 30-day major complications (Clavien-Dindo Grades III-V). A systematic search was undertaken for studies assessing the relationship between obesity and major complications after gastrointestinal surgery. Individual patient meta-analysis was used to analyse pooled results.

RESULTS

This study included 2519 patients across 127 centres, of whom 560 (22.2%) were obese. Unadjusted major complication rates were lower in obese vs normal weight patients (13.0% vs 16.2%, respectively), but this did not reach statistical significance (P = 0.863) on multivariate analysis for patients having surgery for either malignant or benign conditions. Individual patient meta-analysis demonstrated that obese patients undergoing surgery for malignancy were at increased risk of major complications (OR 2.10, 95% CI 1.49-2.96, P < 0.001), whereas obese patients undergoing surgery for benign indications were at decreased risk (OR 0.59, 95% CI 0.46-0.75, P < 0.001) compared to normal weight patients.

CONCLUSIONS

In our international data, obesity was not found to be associated with major complications following gastrointestinal surgery. Meta-analysis of available prospective data made a novel finding of obesity being associated with different outcomes depending on whether patients were undergoing surgery for benign or malignant disease.

Impact of high body mass index on surgical outcomes and long-term survival among patients undergoing esophagectomy: A meta-analysis

BACKGROUND

The impact of high body mass index (BMI, >23/25 kg/m) on surgical outcomes and prognosis in patients with esophageal carcinoma (EC) after undergoing esophagectomy remains controversial. We herein conducted a systematic review and meta-analysis to determine the relationship between high BMI and surgical outcomes and prognosis in patients undergoing esophagectomy for EC.

METHODS

The study search was conducted by retrieving publications from the PubMed, Embase, Web of Science, and CNKI (up to September 8, 2017). Nineteen studies with 13,756 patients were included in this meta-analysis.

RESULTS

We found that high BMI was closely associated with a higher incidence of wound infection (odds ratio [OR]: 1.41, 95% confidence interval [CI]: 1.02-1.97, P = .04), cardiovascular complications (OR: 2.51, 95% CI, 1.65-3.81, P < .0001), and anastomotic leakage (OR: 1.50, 95% CI, 1.21-1.84, P = .0002), but a lower incidence of chylous leakage (OR: 0.59, 95% CI, 0.40-0.88, P = .01) when compared with normal BMI. The high BMI group was not associated with better or worse overall survival (OS) (hazard ratio [HR]: 0.95, 95% CI, 0.85-1.07, P = .4) and disease-free survival (HR: 0.95, 95% CI, 0.72-1.25, P = .72) than the normal BMI group. However, in the subgroup analysis, the pooled result of HRs generated from multivariate analyses suggested that high BMI could improve OS in EC patients (HR: 0.84, 95% CI, 0.76-0.93, P < .01).

CONCLUSIONS

Overweight patients with EC should not be denied surgical treatment, but intraoperative prevention and careful postoperative monitoring for several surgical complications must be stressed for this population. Besides, high BMI might be a prognostic predictor in EC patients; further studies are warranted.

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.

Early breast cancer: why does obesity affect prognosis?

High BMI is associated with an increased risk of breast cancer in post-menopausal women but poorer outcomes in all age groups. The underlying mechanism is likely to be multi-factorial. Patients with a high BMI may present later due to body habitus. Some studies have also indicated an increased incidence of biologically adverse features, including a higher frequency of oestrogen receptor (ER negative) tumours, in obese patients. Obese patients have a higher frequency of surgical complications, potentially delaying systemic therapies, and reports suggest that chemotherapy and endocrine therapy are less effective in patients with BMI ≥30 kg/m2.High BMI is generally interpreted as excess adiposity and a World Cancer Research Fund report judged that the associations between BMI and incidence of breast cancer were due to body fatness. However, BMI cannot distinguish lean mass from fat mass, or characterise body fat distribution. Most chemotherapy drugs are dosed according to calculated body surface area (BSA). Patients with a similar BSA or BMI may have wide variations in their distribution of adipose tissue and skeletal muscle (body composition); however, few studies have looked at the effect of this on chemotherapy tolerance or effectiveness. Finally, adjuvant treatments for breast cancer can themselves result in body composition changes.Research is required to fully understand the biological mechanisms by which obesity influences cancer behaviour and the impact of obesity on treatment effectiveness and tolerance so that specific management strategies can be developed to improve the prognosis of this patient group.

The impact of obesity on esophagectomy: a meta-analysis

The impact of body mass index (BMI) on postoperative outcomes after curative resection for esophageal cancer has been assessed in many studies worldwide with conflicting conclusions. The aim of this meta-analysis is to evaluate the influence of preoperative BMI on surgical and oncologic outcomes after radical surgery for esophageal cancer, in Western studies. A comprehensive electronic search was performed to identify Western publications reporting BMI and outcomes following surgery for esophageal cancer. Articles that did not report preoperative BMI, postoperative morbidity, and early mortality were excluded. Statistical analysis was performed using the OpenMetaAnalyst software (Version 10.10). One hundred and ninety records were examined and 8 studies were included with a total of 2838 patients. The study population was stratified into two groups: a nonobese group (BMI < 30 kg/m2), containing 2199 patients, and an obese group (BMI ≥ 30 kg/m2), with 639 patients. In the obese group, there was an increased risk (up to 35%) of anastomotic leak (P = 0.003; RR: 0.857, 95% CI: 0.497, 0.867). The obese group showed a significantly more favorable five-year overall survival (P = 0.011). Although there was a significant association between anastomotic leak and obesity, patients with obesity also have a better overall 5-year survival. This meta-analysis demonstrates that patients with obesity should be counseled regarding the specific risks of surgery but they can be reassured that despite these risks overall outcome is satisfactory.

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

BACKGROUND

Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world.

METHODS

This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231.

FINDINGS

Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p<0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05-2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p<0·001).

INTERPRETATION

Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication.

FUNDING

DFID-MRC-Wellcome Trust Joint Global Health Trial Development Grant, National Institute of Health Research Global Health Research Unit Grant.