Outcomes After Independent Trainee Versus Consultant-led Emergency Laparotomy: Inverse Propensity Score Population Dataset Analysis

OBJECTIVE

We utilized a population dataset to compare outcomes for patients where surgery was independently performed by trainees to cases led by a consultant.

SUMMARY OF BACKGROUND DATA

Emergency laparotomy is a common, high-risk, procedure. Although trainee involvement to improve future surgeons' experience and ability in the management of such cases is crucial, some studies have suggested this is to the detriment of patient outcomes. In the UK, appropriately skilled trainees may be entrusted to perform emergency laparotomy without supervision of a consultant (attending).

METHODS

Patients who underwent emergency laparotomy between 2013 and 2018 were identified from the National Emergency Laparotomy Audit of England and Wales. To reduce selection and confounding bias, the inverse probability of treatment weighting approach was used, allowing robust comparison of trainee-led and consultant-led laparotomy cases accounting for eighteen variables, including details of patient, treatment, pathology, and preoperative mortality risk. Groups were compared for mortality and length of stay.

RESULTS

A total of 111,583 patients were included in the study. The operating surgeon was a consultant in 103,462 cases (92.7%) and atrainee in 8121 cases (7.3%). Mortality at discharge was 11.6%. Trainees were less likely to operate on high-risk and colorectal cases. After weighting, mortality (12.2% vs 11.6%, P = 0.338) was equivalent between trainee- and consultant-led cases. Median length of stay was 11 (interquartile range 7, 19) versus 11 (7, 20) days ( P = 0.004), respectively. Trainee-led operations reported fewer cases of blood loss >500mL (9.1% vs 11.1%, P < 0.001).

CONCLUSIONS

Major laparotomy maybe safely entrusted to appropriately skilled trainees without impacting patient outcomes.

OGC P31 Learning curve for robot-assisted minimally invasive esophagectomy: A systematic review

Background

Robot- assisted minimally invasive esophagectomy (RAMIE) is gaining increasing popularity as an operative approach. Learning curves to achieve surgical competency in robotic-assisted techniques have shown significant variation in learning curve lengths and outcomes. It is vital to understand the impact of RAMIO implementation on patient outcomes during the initial adoption phase. This systematic review aims to summarise the current literature on learning curves for RAMIE.

Methods

A systematic review was conducted in line with MOOSE (Meta-analyses Of Observational Studies in Epidemiology) guidelines. Electronic databases PubMed, MEDLINE, and Cochrane Library were searched, and articles reporting on learning curves in RAMIE were identified and scrutinized. Studies were included if an assessment of the learning curve was reported, regardless of statistical method was used.

Results

Fifteen studies reporting on 1767 patients were included. Nine studies reported on surgeons with prior experience of robot-assisted surgery prior to adopting RAMIE, with only four studies outlining a specified RAMIO adoption pathway. Learning curves were most commonly reported for lymph node yields and operative times, with significant variation in learning curve lengths (18–73 cases and 20–80 cases respectively). Only a minority of studies (3/9) demonstrated learning curves for patient outcomes (30-day morbidity, 21–51 cases; vocal cord paralysis rates, 12–80 cases).

Conclusions

RAMIE adoption appears possible with minimal impact on clinical outcomes. Robust training through formal programmes or proctorship may be crucial to minimise the adverse effects on operative efficiency and patient care.

OGC P21 EZH2: A novel therapeutic target in oesophageal adenocarcinoma

Background

Enhancer of zeste homologue 2 (EZH2), the catalytic subunit of the histone lysine methyltransferase Polycomb Repressor Complex 2 (PRC2), mediates gene silencing of target genes epigenetically. It is over-expressed and associated with poor outcomes in numerous malignancies. EZH2 inhibitors are currently used in the treatment of follicular lymphomas and epithelioid sarcomas. Oesophageal adenocarcinoma (OAC) has predicted sensitivity to EZH2 inhibition due to the high prevalence of potentially sensitizing mutations. This in vitro study aimed to assess the efficacy of EZH2 inhibitors in the treatment of OAC.

Methods

Bioinformatical analysis of publicly available bulk RNA transcriptomic data from OAC samples included in the Cancer Genome Atlas (TCGA) database was carried out. OAC cell lines OE33, FLO1 and MFD1 cultured in 2D were treated with a panel of EZH2 inhibitors at a range of clinically relevant concentrations either as monotherapies or in combination with OAC standard of care (SOC) chemotherapies. Cell viability was assessed via colorimetric MTS assay at 72hrs and 6 days post-treatment.

Results

Median EZH2 mRNA expression levels calculated from OAC TCGA data were significantly greater than EZH2 mRNA expression in normal oesophageal tissue (p&lt;0.01). OAC patients with high EZH2 expression had reduced median overall survival compared to patients with low EZH2 expression (13.1 months vs 32 months, p= 0.03). EZH2 inhibitors demonstrated efficacy as monotherapies in all 3 cell lines. EZH2 inhibitors in combination with 5-fluorouracil (5-FU) showed greater efficacy than 5-FU alone, demonstrated by reductions in 5-FU half-maximal inhibitory concentration (IC50) values.

Conclusions

These early in vitro results demonstrate the potential of EZH2 inhibition as a novel therapy in OAC, particularly in combination with current chemotherapy agents. Further in vitro work is focused on their efficacy in patient derived tumour organoid models.

Association of Upper Gastrointestinal Surgery of Great Britain and Ireland (AUGIS)/Perioperative Quality Initiative (POQI) consensus statement on intraoperative and postoperative interventions to reduce pulmonary complications after oesophagectomy

BACKGROUND

Pulmonary complications are the most common morbidity after oesophagectomy, contributing to mortality and prolonged postoperative recovery, and have a negative impact on health-related quality of life. A variety of single or bundled interventions in the perioperative setting have been developed to reduce the incidence of pulmonary complications. Significant variation in practice exists across the UK. The aim of this modified Delphi consensus was to deliver clear evidence-based consensus recommendations regarding intraoperative and postoperative care that may reduce pulmonary complications after oesophagectomy.

METHODS

With input from a multidisciplinary group of 23 experts in the perioperative management of patients undergoing surgery for oesophageal cancer, a modified Delphi method was employed. Following an initial systematic review of relevant literature, a range of anaesthetic, surgical, and postoperative care interventions were identified. These were then discussed during a two-part virtual conference. Recommendation statements were drafted, refined, and agreed by all attendees. The level of evidence supporting each statement was considered.

RESULTS

Consensus was reached on 12 statements on topics including operative approach, pyloric drainage strategies, intraoperative fluid and ventilation strategies, perioperative analgesia, postoperative feeding plans, and physiotherapy interventions. Seven additional questions concerning the perioperative management of patients undergoing oesophagectomy were highlighted to guide future research.

CONCLUSION

Clear consensus recommendations regarding intraoperative and postoperative interventions that may reduce pulmonary complications after oesophagectomy are presented.

Phosphodiesterase type 5 inhibitors enhance chemotherapy in preclinical models of esophageal adenocarcinoma by targeting cancer-associated fibroblasts

The chemotherapy resistance of esophageal adenocarcinomas (EACs) is underpinned by cancer cell extrinsic mechanisms of the tumor microenvironment (TME). We demonstrate that, by targeting the tumor-promoting functions of the predominant TME cell type, cancer-associated fibroblasts (CAFs) with phosphodiesterase type 5 inhibitors (PDE5i), we can enhance the efficacy of standard-of-care chemotherapy. In ex vivo conditions, PDE5i prevent the transdifferentiation of normal fibroblasts to CAF and abolish the tumor-promoting function of established EAC CAFs. Using shotgun proteomics and single-cell RNA-seq, we reveal PDE5i-specific regulation of pathways related to fibroblast activation and tumor promotion. Finally, we confirm the efficacy of PDE5i in combination with chemotherapy in close-to-patient and in vivo PDX-based model systems. These findings demonstrate that CAFs drive chemotherapy resistance in EACs and can be targeted by repurposing PDE5i, a safe and well-tolerated class of drug administered to millions of patients world-wide to treat erectile dysfunction.

The Use of miRNAs in Predicting Response to Neoadjuvant Therapy in Oesophageal Cancer

Oesophageal cancer (OC) is the ninth most common cancer worldwide. Patients receive neoadjuvant therapy (NAT) as standard of care, but less than 20% of patients with oesophageal adenocarcinoma (OAC) or a third of oesophageal squamous cell carcinoma (OSCC) patients, obtain a clinically meaningful response. Developing a method of determining a patient's response to NAT before treatment will allow rational treatment decisions to be made, thus improving patient outcome and quality of life. (1) Background: To determine the use and accuracy of microRNAs as biomarkers of response to NAT in patients with OAC or OSCC. (2) Methods: MEDLINE, EMBASE, Web of Science and the Cochrane library were searched to identify studies investigating microRNAs in treatment naïve biopsies to predict response to NAT in OC patients. (3) Results: A panel of 20 microRNAs were identified as predictors of good or poor response to NAT, from 15 studies. Specifically, miR-99b, miR-451 and miR-505 showed the strongest ability to predict response in OAC patients along with miR-193b in OSCC patients. (4) Conclusions: MicroRNAs are valuable biomarkers of response to NAT in OC. Research is needed to understand the effects different types of chemotherapy and chemoradiotherapy have on the predictive value of microRNAs; studies also require greater standardization in how response is defined.

Minimally Invasive Approach in Boerhaave's Syndrome: Case Series and Systematic Review

Introduction: Boerhaave's syndrome is a life-threatening spontaneous perforation of the esophagus associated with significant morbidity and mortality. Historically, thoracotomy has been the mainstay of treatment, but is associated with high morbidity and pain. Minimally invasive approaches provide alternative treatment possibilities. This systematic review together with inclusion of a case series from a tertiary esophagogastric unit assesses current evidence focused on minimally invasive surgical management of this condition. Methods: A systematic review was conducted in line with MOOSE (Meta-analyses Of Observational Studies in Epidemiology) guidelines. Electronic databases PubMed, MEDLINE, and Cochrane Library were searched, and articles focusing on the minimally invasive management of Boerhaave's syndrome were identified and scrutinized. We also report demographics and outcomes for a consecutive case series of patients with acute Boerhaave's syndrome managed via thoracoscopy. Results: Fifteen studies were included comprising 5 retrospective cohort studies and 10 case reports. Management strategies were divided into three categories: thoracoscopic, endoscopic, and laparoscopic. Overall mortality rates for each treatment modality were 2%, 13%, and 33%, and treatment success rates 98%, 38%, and 67%, respectively. Postoperative infective complications were seen in 79% of patients, with only 2 patients requiring salvage thoracotomy. In our local case series, we report 4 consecutive patients managed with thoracoscopy, with a 100% treatment success rate. Conclusion: Minimally invasive approaches in the management of Boerhaave's syndrome are safe and effective. We propose a selective management algorithm involving a minimally invasive approach to management of this life-threatening condition. Registered with local clinical outcomes team as service evaluation. (Approval number sev/0171).

922 Pre-Operative Chest X-Ray Prior To Aneurysm Surgery Is Unnecessary

Aim

Over 4100 elective abdominal aortic aneurysm (AAA) cases are performed each year in the UK. In our tertiary centre the anaesthetic pre-operative protocol for these patients includes a chest x-ray (CXR), because some risk factors for aneurysmal disease (smoking, older age) cross over with those for lung cancer. This study was performed to see if the CXR changed management in AAA patients.

Method

A retrospective radiology review of 191 consecutive patients who had an elective AAA repair at one unit in 2017-2018 was carried out. Computed tomography angiogram (CTA) and CXR findings were compared. Where an abnormality was reported, patient records were reviewed and the impact of the abnormal result on the patient journey assessed.

Results

Of 191 patients, 148 had pre-op CXRs. Of the CXRs, 60 reported abnormalities, most of which were minor (cardiomegaly, atelectasis, reticular shadowing). Of the 60, 28 had no lung abnormalities on CTA, 18 had not had a reported CTA, 8 corresponded with the CTA and 6 had a different chest abnormality reported on the CTA. 2 patients had CTs of the chest following CXR findings and no patients had an operation cancelled or delayed due to findings on CXR.

Conclusions

Each CXR costs around £20 including reporting and administration time. In addition, there is inconvenience to the patient and additional radiation dose. None of the pre-operative CXRs resulted in a change to patient operative management therefore the requirement for pre-operative CXR was removed from the units’ protocol.

1025 Readmission & Mortality Rates Following Enhanced Recovery After Surgery (ERAS) For Colorectal Procedures at An Island DGH

Introduction

Colorectal surgery under ERAS reduces postoperative morbidity by 40-50% and shortens length of hospital stay by 2-3 days. The 2018 National Bowel Cancer Audit reported a 30-day readmission rate of 10.5% for colorectal surgery under ERAS and a 90-day mortality rate of 2% nationally. Evidence shows readmission rates increase with discharge C-reactive protein (CRP); 16.5% when CRP &gt;100 mg/L and 6% when CRP &lt;100 mg/L.

Method

Data was collected prospectively at a small island DGH on 89 patients from September 2018 - March 2020.

Results

The 30-day readmission rate was 7.9% and the 90-day mortality rate was 0% locally. Six (86%) of the readmitted patients had a left-sided colorectal disease (potentially due to increased risk with a colo-colonic anastomosis). Five (71%) patients required return to theatre; four due to anastomotic leaks and one due to a wound collection. 43% of readmitted patients had upward white cell count/c-reactive protein (WCC/CRP) trends on discharge. Readmitted patients had a mean discharge CRP result of 150 (range 15.9 - 311).

Conclusions

Colorectal surgery under ERAS at our institution is at a high standard stemming from effective staff education and post-operative patient counselling. This study provides evidence that WCC/CRP trend is related to postoperative prognosis.

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.

Prevalence and Sonographic Detection of Gallbladder Polyps in a Western European Population

BACKGROUND

Gallbladder cancer is rare but associated with significant morbidity and mortality necessitating the early identification of premalignant and malignant lesions to improve overall prognosis. Despite limited evidence regarding the effectiveness of transabdominal ultrasound (US) in the detection of gallbladder polyps, it plays a key role in current European guidelines. The aim of this study was to investigate gallbladder polyp prevalence in a western European population and assess the diagnostic accuracy of transabdominal US.

METHODS

Data from patients who underwent cholecystectomy for US detected gallbladder polypoid lesions at four hospitals in Ireland and the United Kingdom between 2010 and 2018 were retrospectively collected. Patient demographics, ultrasonographic, and histopathologic findings were analyzed.

RESULTS

A total of 134 patients underwent cholecystectomy for US-detected gallbladder polyps. After histopathologic examination, pseudopolyps were found in 75 (56%) specimens with dysplastic or malignant polyps seen in only six (4.5%) specimens. Mean size for neoplastic polyps was 33 mm. The positive predictive value for US in detecting neoplastic polyps in this study was 4.5%, which is significantly lower than the 10%-15% reported previously.

CONCLUSIONS

Although the prevalence of neoplastic polyps in this study is higher than in the previous literature, the distribution of pseudopolyps and true polyps is as expected. With all malignant polyps being >10 mm in diameter, these findings support the current size thresholds stated in European guidelines. The poor diagnostic accuracy of US demonstrated may have led to significant number of patients undergoing unnecessary surgical intervention, further supporting the argument for improved strategies for the investigation of gallbladder polyps.

Robotic rectal cancer surgery in obese patients may lead to better short-term outcomes when compared to laparoscopy: a comparative propensity scored match study

PURPOSE

Laparoscopic rectal surgery in obese patients is technically challenging. The technological advantages of robotic instruments can help overcome some of those challenges, but whether this translates to superior short-term outcomes is largely unknown. The aim of this study is to compare the short-term surgical outcomes of obese (BMI ≥ 30) robotic and laparoscopic rectal cancer surgery patients.

METHODS

All consecutive obese patients receiving laparoscopic and robotic rectal cancer resection surgery from three centres, two from the UK and one from Portugal, between 2006 and 2017 were identified from prospectively collated databases. Robotic surgery patients were propensity score matched with laparoscopic patients for ASA grade, neoadjuvant radiotherapy and pathological T stage. Their short-term outcomes were examined.

RESULTS

A total of 222 patients were identified (63 robotic, 159 laparoscopic). The 63 patients who received robotic surgery were matched with 61 laparoscopic patients. Cohort characteristics were similar between the two groups. In the robotic group, operative time was longer (260 vs 215 min; p = 0.000), but length of stay was shorter (6 vs 8 days; p = 0.014), and thirty-day readmission rate was lower (6.3% vs 19.7%; p = 0.033).

CONCLUSIONS

In this study population, robotic rectal surgery in obese patients resulted in a shorter length of stay and lower 30-day readmission rate but longer operative time when compared to laparoscopic surgery. Robotic rectal surgery in the obese may be associated with a quicker post-operative recovery and reduced morbidity profile. Larger-scale multi-centre prospective observational studies are required to validate these results.

Creating the BCMSV database: cataloguing and indexing earlier English verse

The article describes the creation of an innovative computer database of manuscript English verse in Leeds University Library, outlining the record structure and the free-text search techniques, and explaining in detail the nature of the 17 different fields. It discusses the indexing prob lems encountered in the course of the work, particularly the best means of subject indexing. The solution, unconventionally, has been a discur sive content field in which the user of the database is explicitly informed about the poem's subject matter and emphases in words not drawn from a controlled thesaurus, but nevertheless designed to be helpful for retrieval purposes. It is recognized that this particularized approach will have drawbacks for researchers necessitat ing the use of synonyms and other techniques, but the database has already successfully answered many different kinds of enquiry. BCMSV aims to be an informative finding list, not a comprehensive catalogue, and one of the intentions is to encourage scholars to come to Leeds to see the manuscripts for themselves rather than provide long-distance answers to all possible questions.