bluuebunny/crossref_metadata_2025_split huggingface dataset:
Causes, Responses, and Implications of Anthropogenic versus Natural Flow Intermittence in River Networks
Authors: Datry Thibault , Truchy Amélie , Olden Julian D , Busch Michelle H , Stubbington Rachel , Dodds Walter K , Zipper Sam , Yu Songyan , Messager Mathis L , Tonkin Jonathan D , Kaiser Kendra E , Hammond John C , Moody Eric K , Burrows Ryan M , Sarremejane Romain , DelVecchia Amanda G , Fork Megan L , Little Chelsea J , Walker Richard H , Walters Annika W , Allen Daniel 
Published: December 2022

AbstractRivers that do not flow year-round are the predominant type of running waters on Earth. Despite a burgeoning literature on natural flow intermittence (NFI), knowledge about the hydrological causes and ecological effects of human-induced, anthropogenic flow intermittence (AFI) remains limited. NFI and AFI could generate contrasting hydrological and biological responses in rivers because of distinct underlying causes of drying and evolutionary adaptations of their biota. We first review the causes of AFI and show how different anthropogenic drivers alter the timing, frequency and duration of drying, compared with NFI. Second, we evaluate the possible differences in biodiversity responses, ecological functions, and ecosystem services between NFI and AFI. Last, we outline knowledge gaps and management needs related to AFI. Because of the distinct hydrologic characteristics and ecological impacts of AFI, ignoring the distinction between NFI and AFI could undermine management of intermittent rivers and ephemeral streams and exacerbate risks to the ecosystems and societies downstream.
BS O02 Long-term survival after sleeve gastrectomy versus gastric bypass in a bi-national cohort study
Authors: Markar Sheraz , Holmberg Dag , Santoni Giola , Kauppila Joonas , Lagergren Jesper 
Published: December 2022

Abstract

Background
Bariatric surgery prolongs life expectancy in severely obese individuals, but it is uncertain which of the two dominating bariatric procedures, sleeve gastrectomy or gastric bypass, offers the best long-term survival.

Methods
This was a population-based cohort study comparing primary laparoscopic sleeve gastrectomy to gastric bypass for obesity in Sweden and Finland between January 1, 2007 and December 31, 2020. The risk of all-cause mortality was calculated using multivariable Cox regression, providing hazard ratios (HR) with 95% confidence intervals (CI) adjusted for age, sex, hypertension, diabetes, Charlson comorbidity index, country, and calendar year.

Results
Among 61,503 patients (median age 42 years; 75.4% women), who contributed 415,712 person-years at risk (mean 6.8 person-years), 1,571 (2.6%) died during follow-up. Compared to patients who underwent gastric bypass (n=51,891, 84.4%), the sleeve gastrectomy group (n=9,612, 15.6%) had similar all-cause mortality during the entire study period (HR=0.98, 95% CI 0.81–1.20), but decreased all-cause mortality in more recent years (HR=0.72, 95% CI 0.54–0.97, from 2014 onwards). Diabetes interacted statistically significantly with the type of bariatric surgery, with higher all-cause mortality after sleeve gastrectomy than gastric bypass (HR=1.54, 95% CI 1.06–2.24).

Conclusions
The overall survival following sleeve gastrectomy seems to compare well with gastric bypass, and may even be better during recent years. A tailored surgical approach in relation to patients’ diabetes status may optimize survival in patients selected for bariatric surgery, i.e. sleeve gastrectomy for non-diabetic patients and gastric bypass for patients with diabetes.
HPB O06 Developing a patient-derived model of cholangiocarcinoma using Precision Cut Tissue Slices (PCTS)
Authors: Gilbert Timothy , Randle Laura , Diaz-Nieto Rafael , Jones Robert , Fenwick Stephen , Goldring Christopher , Malik Hassan 
Published: December 2022

Abstract

Background
Cholangiocarcinoma (CCA) is an aggressive malignancy with increasing incidence and persistently poor prognosis. None surgical treatment options for these patients are limited and a preponderance to chemoresistance means the benefits from chemotherapy are modest. The development of new targeted therapeutic strategies that prolong survival and reduce the risk of recurrence post-surgery are required. Accurate models that recapitulate tumour biology are essential to test and identify these novel therapies. Precision-cut tissue slices (PCTS) are patient-derived whole tissue explants that can be cultured ex-vivo. By retaining all aspects of the tumour micro-environment they recapitulate critical aspects of cancer biology, a significant advantage over 3D organoid culture. Our aim is to establish the use of the PCTS technique in CCA as the first step towards creating a patient-derived model of cholangiocarcinoma for use as a drug discovery platform.

Methods
CCA tissue samples and matched healthy liver tissue were collected from the operating theatre during surgical resection from fully consented patients. Multiple tissue slices (250μm, 5mm diameter) were prepared using a Krumdiek tissue slicer. Tissue slices were randomly incubated in triplicate and cultured for 0–15 days in 24 well plates. Tissue perfusion and air-liquid interface was maintained using Millipore well inserts. Tissue viability was determined at timepoints utilising MTS and ATP viability assays along with histological markers of proliferation (Ki-67) and apoptosis (cleaved-caspase 3). Maintenance of tissue morphology and phenotype during culture was confirmed on histological H&E staining and by staining of tumour specific markers (e.g CK19) on IHC and Western Blot.

Results
Thus far n=4 patients have had PCTS generated (3=pCCA 1=iCCA) from their tumour along with matched healthy liver. Following optimisation of the experimental protocol viability of the matched normal and tumour tissue slices can be maintained for upto 10 days, as assessed via in-situ MTS assay. Histological assessment of tissue slices harvested at day 0, 1,3,7 of culture shows the morphological and phenotypic structures of the source tumour to be maintained during ex-vivo culture. Viability of the tumour cells was additionally confirmed through the absence of cleave-caspase 3 markers of apoptosis on IHC staining.

Conclusions
This initial work has shown it is feasible to generate PCTS of CCA from resected surgical specimens with good viability. Further work is still required to ensure that our model retains a robust recapitulation of the in-vivo tumour including examination of the gene-expression profile. However, these initial results provide encouragement for the use of PCTS as a patient-derived model for drug discovery in CCA.
HPB V08 Fluorescence Image Guidance (FIG) in minimally invasive liver surgery- can it help identify deep margins?
Authors: Karmarkar Rahi , Tanase Andrei , Aroori Somaiah 
Published: December 2022

Abstract

Background
Despite recent advances in imaging modalities and surgical techniques in liver resection, the rate of R1 resection in liver tumours is still high. Currently, liver surgeons plan the type of liver resection based on information gathered from pre-operative cross-sectional imaging, intraoperative naked eye examination/palpation, and intra-operative ultrasound (IOUS) examination. Naked eye examination and palpation help identify superficially located tumours; however, they do not help localise deeply seated small tumours or accurately mark tumour margins. Moreover, the lack of tactile feedback in the case of laparoscopic liver surgery makes tumour identification further difficult. Currently, IOUS is the most sensitive test for detecting liver tumours – in both open and laparoscopic liver surgery. However, it does not give a real-time visual clue on transection margins. Identification and marking of the deep margin of the tumour are not possible with IOUS. We describe the use of FIG using indocyanine green (ICG) dye in localisation and identification of deep margins of a segment seven liver metastasis.

Methods
We present a video demonstration of the use of FIG in the identification of deep resection margins of a segment seven tumour in a 41 year-old female patient. Initially, the tumour was not visible to the naked eye owing to its location, which made the identification of the tumour and its margins with IOUS challenging. We can see in the video how ICG identified the tumour readily and helped identify the resection margins, especially the deep margin, which was challenging to identify with IOUS. The histology report confirmed that all margins were free of tumours.

Results
We found that FIG is a robust, objective, real-time navigation tool that can overcome some of the shortfalls associated with and help accurately identify tumour resection margins. When used along with IOUS, we believe that FIG using ICG can potentially reduce R1 resection rates in liver tumours.

Conclusions
We found that FIG is a robust, objective, real-time navigation tool that can overcome some of the shortfalls associated with and help accurately identify tumour resection margins. When used along with IOUS, we believe that FIG using ICG can potentially reduce R1 resection rates in liver tumours.
OGBN O01 Laparoscopic large hiatus hernia repair with mesh versus suture: a systematic review and meta-analysis
Authors: Rajkomar Kheman , Wong Michael , Gall Lewis , MacKay Colin , MacDonald Andrew , Forshaw Matthew , Craig Carol 
Published: December 2022

Abstract

Background
Whilst the use of laparoscopy in the repair of large hiatus hernia (LHH) has become mainstream, the prevention of post operative hernia recurrence and other adverse events has remained a challenge. Mesh reinforcement of suture cruroplasty has been considered as a potential solution. However the paucity of well constructed and powered randomised control trials (RCT) with long term followup makes an assessment of its real impact difficult.
The aim of this review is to evaluate the effectiveness of mesh reinforcement of LHH repair, with regards to postoperative outcomes.

Methods
A systematic search of articles was conducted in PubMed, Medline and Embase using the PRISMA guidelines. RCTs and observational studies (OS) comparing recurrences and reoperations in those patients with LHH (&gt;30% stomach in chest, &gt;5cm hiatal defect, hiatal surface area &gt;10 mm2) repair who had mesh vs no mesh were assessed quantitatively. The impact of mesh on significant intraoperative/postoperative surgical complications and mortality were qualitatively assessed.

Results
Pooled data included five RCTs and fourteen OS with 1670 patients (824 with no mesh, 846 with mesh). There was a significant reduction in total recurrence rate with mesh (OR 0.44, 95% CI 0.25 to 0.80, p = 0.007). Mesh use did not cause significant reduction in recurrences &gt;2cm (OR 0.94, 95% CI 0.52 to 1.67, p = 0.83) or significant reduction in reoperation rates (OR 0.64, 95% CI 0.39 to 1.07, p = 0.09). None of the meshes were found to significantly reduce recurrence or reoperation rate on subgroup analysis, although the number of studies using a single mesh type was limited. Major morbidity rates associated with LHH repair included mesh erosion with foregut resection (from synthetic mesh) and esophageal perforation and were 0.71% and 0.36% respectively. An overall mortality rate of 0.3% was found in the pooled patients.

Conclusions
Mesh reinforcement in LHH is protective against total recurrence. However there is no significant reduction in large recurrences (&gt;2cm) or reoperation rate. If synthetic mesh is to be used patients need to be informed of the risk of mesh erosion.
OGBN O04 Upper Gastrointestinal Training in the UK & Ireland – a Roux Group Study
Authors: Robinson David , Zakeri Roxanna , Laing Richard , Choh Clarisa , Abouelazayem Mohamed , Askari Alan , Bradley Alison , Brown Leo , Currie Andrew , Elmasry Mohamed , Evans Richard , Gall Tamara , Jerome Ellen , Raftery Nicola , Samuel Maria , Spiers Harry , Chan Benjamin 
Published: December 2022

Abstract

Background
Surgical training programmes in the United Kingdom and Ireland (UK&I) are in a transition period evidenced by new surgical curricula. This study is the first to collate the opinions of UK&I trainee and consultant surgeons regarding the current Upper Gastrointestinal (UGI) training model.

Methods
A questionnaire was developed and distributed via national UGI societies and the social media platform, Twitter. A total of 241 responses were received with all UK&I regions represented.

Results
The median time to Certificate of Completion of Training (CCT) of 13 years was considered reasonable (50.2%), however the majority (67.2%) found training to be unfocused. The suggested targets for publications, presentations and audits were 3–5 (trainee vs consultant &lt;3 vs 3–5, p&lt;0.001), &lt;3 (&lt;3 vs 3–5, p=0.002) and 3–5 (&lt;3 vs 3–5, p&lt;0.001) respectively. The majority (61.9%) considered a higher academic degree advantageous but felt it should not be compulsory. Interestingly, most respondents (63.5%) had or planned to undertake one. Crucially, there were geographical discrepancies in access to training, particularly in bariatrics, robotic surgery, and endoscopy. Proficiency in diagnostic endoscopy was deemed essential for CCT and consultant practice (81.7% and 67.6% respectively). The current index UGI operative requirements were felt to be achievable (87.6%) but inadequate for day one consultant practice (74.7%), an opinion shared by both the trainee and consultant groups (p=0.662). Reassuringly, most respondents (76.3%) deemed there to be a role for on-the-job operative training following consultant appointment. Post-CCT fellowships were not considered necessary for consultant appointment, however the majority (73.6%) again recognised its advantage.

Conclusions
While variations were seen in the opinions of trainee and consultant surgeons, the current CCT requirements as outlined by the Joint Committee on Surgical Training are consistent with the overall perspective of the UGI community. Areas for improvement include flexibility in geographical working and provisions for endoscopy training, to ensure equal access.
OGBN V09 Laparoscopic Resection of Epiphrenic Diverticulum and Hellers Cardiomyotomy for achalasia
Authors: Frank Amy , Kostalas Marcos , Andrews Stuart 
Published: December 2022

Abstract

Background
Epiphrenic diverticula are a rare form of diverticulum located in the distal oesophagus. Symptoms are varied as patients may be asymptomatic or present acutely with dysphagia and regurgitation. This video presentation is a case report and discussion of a patient requiring laparoscopic resection of an epiphrenic diverticulum and Hellers cardiomyotomy for concurrent achalasia.

Methods
The case of a 58 year old man is presented, who attended as an emergency with severe malnutrition and aspiration pneumonia secondary to dysphagia. Initial investigations included an upper GI endoscopy, barium swallow and CT scan which demonstrated a large oesophageal diverticulum and undiagnosed achalasia.

Results
The video presentation explores the operative technique used during this case in order to resect the epiphrenic diverticulum and perform a subsequent Hellers cardiomyotomy for achalasia.

Conclusions
Operative intervention was successful and the patient was discharged on day 2 post-operatively with no further complications. This video presentation stimulates further discussion regarding the management and operative technique utilised in epiphrenic diverticulae.
OGC O06 An international cohort study of prognosis associated with pathologically complete response following neoadjuvant chemotherapy vs. chemoradiotherapy of surgical treated esophageal adenocarcinoma
Authors: Markar Sheraz , Cools-Lartigue Jonathan , Mueller Carmen , Hofstetter Wayne , Nilsson Magnus , Ilonen Ilka , Soderstrom Henna , Rasanen Jari , Gisbertz Suzanne , Hanna George , Elliott Jessie , Reynolds John , Kisiel Aaron , Griffiths Ewen , van Berge Henegouwen Mark , Ferri Lorenzo 
Published: December 2022

Abstract

Background
Objective: To compare overall (OS) and recurrence-free survival (RFS) in esophageal adenocarcinoma patients with a complete pathological response (pCR) following neoadjuvant chemotherapy (nCT) or neoadjuvant chemoradiotherapy (nCRT).

Background
In the absence of survival differences in several prior studies comparing nCT with nCRT, the higher rate of pCR after nCRT has been suggested as reason to prefer this modality over nCT.

Methods
An international cohort study included data from 8 high-volume centers. Inclusion criteria was patients with esophageal adenocarcinoma, between 2008 and 2018, who had a pCR following nCT or nCRT. Univariate analysis was used to compare demographic factors, and Kaplan-Meier survival analysis used to compare 5-year OS and RFS between groups.

Results
465 patients with pCR following neoadjuvant treatment were included; 132 received nCT and 333 received nCRT. There was no statistically significant difference in 5-year OS between groups (78.8% (nCT) vs. 65.5% (nCRT), p=0.099), with a similar result demonstrated in multivariate analysis (HR=1.19, 95%CI 0.77 to 1.84). 5-year RFS was significantly reduced in patients with a pCR following neoadjuvant chemoradiotherapy (75.3% (nCRT) vs. 87.1% (nCT), p=0.026). Multivariate analysis confirmed nCRT was associated with a poorer 5-year RFS (HR=1.70, 95%CI 1.22 to 2.99). nCRT associated with a significantly greater prevalence of 5-year distant recurrence (Odds ratio = 2.50, 95%CI 1.25–4.99).

Conclusions
The results of this international cohort study show that the prognosis of pCR following different neoadjuvant regimes differs, bringing into question the validity of this measure as an oncological surrogate when comparing neoadjuvant treatment schemes for esophageal adenocarcinoma.
OGBN P07 Fenestrating vs Reconstituting - Outcomes following 170 subtotal cholecystectomies
Authors: Thomas Christophe , Wintrip Dorothy , Horgan Liam , Brown Jamie 
Published: December 2022

Abstract

Background
Laparoscopic subtotal cholecystectomy (LSC) is a recognised option when the “critical view” cannot be safely delineated. It carries a high morbidity rate with increased frequencies of a bile leak occurring however reducing the risk of bile duct injury. LSC can be classified into fenestrating or reconstituting cholecystectomy and surgical practice varies as reconstituting is considered to be more complex. Our aim of the study was to look at LSC with respect to the techniques used, complications and the overall outcomes.

Methods
All adult patients undergoing LSC between January 2015 – December 2021 were retrospectively identified on our electronic database. Data gathered included: Patient demographics, previous acute biliary presentations, operative details/technique, length of stay (LOS), 30-complications, 30-day mortality, readmissions and follow up investigations/procedures. Descriptive statistics, Chi squared, and relative risk were used to analyse results.

Results
170 patients underwent LSC in the study period with the rate increasing most years. Median age was 67 with 86:84 Female to Male ratio. Rates varied drastically between different surgeons from 0.1% to 19% compared to total number of laparoscopic cholecystectomies. 130 (76%) were performed in the acute setting and 63/170 (37%) had previous acute biliary presentations. Median LOS was 5 days. Most patients had Fenistrating LSC (155 [67.6%] vs. 55 [32.3%]).
80 (47%) patients had complications. These were graded by Clavin-dindo grade: I – 3 (3.7%); II – 34 (42.5%); IIIa – 26 (32.5%); IIIb – 16 (20%) and IV – 1 (1.25%). The most frequent complication was bile leak; 60 (35.2%) followed by collection 8 (4.7%). Other notable complications were pancreatitis; 3 (1.7%), AKI; 2 (1%), bile duct injury; 1 (0.5%) and duodenal injury; 1 (0.5%). 16 (9.4%) patients had returns to theatre, 14 (8.2%) patients had readmissions and 35 (20.5%) had multiple attendances to the day unit following discharge. Further analysis demonstrated that that fenestrated technique was associated with a greater risk of bile leak (p&lt;0.01 RR 2.1 [95% C.I. 1.3–6.3]) and post operative ERCP (p&lt;0.01 RR 3.8 [95% C.I. 1.6–14]). 2 (1.1%) patients required completion cholecystectomy, one form each technique.

Conclusions
We present one of the largest single unit datasets on LSC, and the 2nd largest from UK population. Our rate of LSC is increasing, likely as a safe alternative to open conversion, with large surgeon variability. The majority are performed in the acute setting with the fenestrated technique. We have demonstrated however that LSC has a high morbidity, both in reoperation/reintervention rate, readmission and complications accompanied by high follow-up requirement. Despite fenestrated being the favoured technique in our unit we have shown that it has poorer outcomes. Our data would suggest that if LSC is to be performed then the reconstituted technique should be used if possible.
OGBN P09 Sharing the experience of the use of Spyglass DS - guided electrohydraulic lithotripsy (SG-EHL) in the treatment of large gallstone causing Bouveret syndrome
Authors: Kouli Tasnim , Gresz Rahel , Abdelwahab Sameh , Shaalan Ramy , Zino Samer 
Published: December 2022

Abstract

Background
Less than 1% of intestinal obstruction is accounted for by gallstone ileus. Gallstone ileus is a mechanical intestinal obstruction resulting from gallstone impaction within the gastrointestinal tract. Under 3% of gallstone ileus are caused by gallstone impaction in the duodenum or pylorus, which can give rise to a gastric outlet obstruction, described by Bouveret in 1896.
Surgical intervention involves the removal of the stone by either a gastrotomy or duodenotomy, which is associated with significant morbidity. Advancement in endoscopic techniques, allows for more complex procedures, therefore, reducing the need for a surgical intervention and its accompanying morbidity.
This abstract presents a rare case of a large gallstone (22mm×34mm) partially impacted in the duodenum of a 92-year-old female, which was treated with the Spyglass DS-guided electrohydraulic lithotripsy (DS-EHL).

Methods
A 92-year-old female with a previous history of gallstone ileus was treated by surgical intervention. The patient continued to complain of abdominal discomfort and occasional vomiting.
A CT scan revealed a fistulous communication to the duodenal bulb, containing a large gall stone (22mm x34 mm). After consultation with the patient, an initial assessment with the use of standard endoscopy under general anaesthesia confirmed the visualisation of a portion of the gallstone in the duodenum, hanging through a well-established cholecysto-dudenal fistula.
SPyglass DS - guided lithotripsy (SG-EHL) was used in the treatment of the large gallstone.

Results
Electrohydraulic lithotripsy (EHL) was attempted through the standard gastroscope, but we were unable to secure a safe position to target the stone. Therefore, a side view duodenoscope was used along with the SpyGlass DS to obtain good visualisation and stable access to target the stone with the EHL. The Spyglass guided electrohydraulic lithotripsy (SG-EHL) was used to fragment the stone. Despite consuming four EHL wires and using higher settings, we only managed to break the shell of the stone, reducing its size by approximately 3mm all around. The laser was not available at the time; therefore, the procedure was concluded. The patient had an uneventful recovery and was discharged home. No further symptoms were recorded by patient on follow up 5 months later.

Conclusions
Endoscopic management of an impacted gallstone causing gastric outlet obstruction is found to be safe and carries less morbidity than the traditional surgical approach. Therefore, it should be considered for being the procedure of choice to treat patients with Bouveret syndrome. Laser lithotripsy should be available on standby for cases that involve stones that are harder to break.