bluuebunny/crossref_metadata_2025_split huggingface dataset:
O093 Manipulating the hypoxia induced radioresistance in rectal cancer
Authors: Fok M , Fok M , Fowler H , Clifford R , Hill R , Grundy G , Parsons J , Vimalachandran D 
Published: May 2023

Abstract

Introduction
Locally advanced rectal cancer is primarily treated with radiotherapy and chemotherapy. Tumour hypoxia induces strong radioresistance, although the reasons for this characteristic are still unclear. This research explores the mechanistic and biological factors underlying hypoxia-induced radioresistance, and development of novel therapeutic strategies to overcome this.

Methods
HCT116 and HT29 CRC cell lines were incubated in normoxia (21% O2) and hypoxic conditions (1% O2). Cells were irradiated at varying dosages of x-ray radiation before undergoing clonogenic survival assay, comet assay to assess DNA double strand break damage and repair, or immunobloting to investigate cell death-related factors. HIF1α and HIF1b siRNA knockdowns were used to assess radioresponse in hypoxia. Metformin was used to treat cells prior to radiation and assess cell survival.

Results
Hypoxia induces strong radioresistance in CRC cells compared to relative normoxia in clonogenic survival assays. Neutral comet assays showed no significant difference in double strand break (DSB) repair kinetics following irradiation in hypoxia compared to normoxia. Immunoblotting analysis demonstrates activation of hypoxia-inducible factor 1a (HIF1a) in hypoxia but not in normoxia. HIF1α and HIF1b siRNA knockdowns did not show any improvement in radioresistance. Metformin did not improve radiosensitivity of CRC cells under different oxygen conditions.

Conclusion
Hypoxia induces strong radioresistance in cultured CRC cells which is not explained by x-ray-induced DSB damage and the efficiency of its repair. HIF1a is activated in hypoxia alone and may contribute to this resistance. Metformin alone is unable to overcome this resistance and other therapeutic targets need to be explored.
O111 Defining humanitarian surgery: an international Delphi process
Authors: McKnight G , Friebel R , Marks I , Almaqadma A , Salem M , Tientcheiu T , Saleh R , Ryan-Coker M , Emodi R , Seida M , Barden J , Leather A , Hargest R 
Published: May 2023

Abstract

Introduction
Over the last decade there has been an exponential increase in the terms “global surgery” and “humanitarian surgery”. However, the terms are often used interchangeably and there is no fixed definition of ‘humanitarian surgery’. This makes it difficult to compare interventions, outcomes and cost effectiveness since a wide variety of activities are included in these global or humanitarian surgery programmes.

Methods
A Delphi process was used over 3 rounds using online software to facilitate responses. A core set of academics and global surgery leaders were invited by targeted email and a snowball sampling effect was used to target responses form Low/Middle Income Countries. Predetermined inclusion criteria were used to ensure the validity of respondents. A Likert scale of 1-6 was used, group agreement was indicated by a median of 3 4 and group consensus was indicated by an interquartile range of £ 2. Intraclass correlation was used to assess stability of response.

Results
Round 1 generated 25 statements, across 4 themes: Who, What, Where and When. Of these, 10 reached agreement and consensus after Rounds 2 and 3. These 10 statements were then used as the basis for the definition of ‘Humanitarian Surgery’.

Conclusion
By agreeing the definition of ‘Humanitarian Surgery’, this will allow comparison of activities within the field to ensure they are appropriate, provide a high quality of care and are cost effective. Debate should now move to focus on ensuring Humanitarian Surgery is delivered to the highest possible standard wherever and whenever it is required.
O132 Preliminary results of radiofrequency ablation for haemorrhoidal disease at a district general hospital
Authors: Win M , Ngo V , Rajaganeshan R 
Published: May 2023

Abstract

Introduction
Haemorrhoidal disease (HD) is a common perianal condition. There is still limited data on the role of minimally invasive surgery for HD. The aim of our study was to report the outcome of radiofrequency ablation of haemorrhoids under local anaesthetic (RAFAELO) at our institution.

Methods
23 patients who had a day-case RAFAELO procedure under local anaesthesia without sedation by a single surgeon from March to October 2022 were retrospectively reviewed. We analysed patients’ demographics, haemorrhoid severity score (HSS), the health's condition scale in EQ-5D-5L questionnaire, and recurrence rate.

Results
The mean age of patients was 50 years (SD 14). 65% were male whereas 35% were female. Majority of haemorrhoids (48%) were Grade 3A. Most of the cases had previous procedures such as rubber band ligation (57%) and hemorrhoidal dearterialization (9%). Only 34% had no prior hemorrhoidal surgery. The mean HSS score significantly improved from 13.2 (SD 4.9) to 4 (SD 2.2) with p &lt; 0.001 postoperatively. The health's condition scale became significantly lower from 64 (SD 23.6) to 23.9 (SD 14.6) with p &lt; 0.001. The median length of follow up was 2 months (range 1-5 months). There was no acute postprocedural complication but there was a recurrence rate of 13% requiring further procedures.

Conclusion
This study supports previous findings that RAFAELO is a safe and effective procedure for HD. It also highlights that it can be performed in the out-patient setting safely. However, further studies with larger samples, longer follow-up and comparison with other procedures are suggested.
O135 Efferent limb stimulation prior to loop ileostomy closure- a meta-analysis
Authors: Lloyd A , Hardy N , Hechtl D , Toale J , Clancy C , Whelan M , O’Riordan J , Kavanagh D , Sahebally S 
Published: May 2023

Abstract

Introduction
Postoperative ileus (POI) remains a common phenomenon following loop ileostomy closure. We aimed to determine whether preoperative physiological stimulation (PPS) of the efferent limb reduced the incidence of POI.

Methods
A PRISMA-compliant meta-analysis searching PubMed, EMBASE and CENTRAL databases from inception until Oct 2022, was performed. All studies comparing PPS versus no stimulation were included. The primary objective was the incidence of POI whilst secondary objectives included time to resume oral diet, nasogastric tube (NGT) placement postoperatively, time to first passage of flatus/stool, length of stay (LOS) and other complications. Random effects models were used to calculate pooled effect size estimates. Sensitivity analyses were also performed.

Results
Four studies (3 randomized, 1 prospective) capturing 293 patients (140 PPS, 153 no-stimulation) were included. The PPS group was associated with a lower POI incidence (10.7 vs. 26.8%, OR 0.27, 95%CI=0.09-0.86, p=0.03), quicker time to resume oral diet (MD -1.34 days, p=0.02), shorter LOS (MD -1.43 days, p=0.001) and fewer complications (OR 0.37, p=0.008). However, there was no difference in the requirement for NGT placement (OR 0.50, p=0.12) or time to first passage of flatus/stool (MD -0.71 days, p=0.24). On sensitivity analysis, focusing on randomized data only, the difference observed in POI rates was lost (OR 0.35, p=0.10) whereas the results of the secondary objectives prevailed.

Conclusion
Efferent limb stimulation prior to surgery appears to result in a quicker time to resume oral diet, shorter LOS but similar POI rates. Further studies are needed to confirm those findings.
O136 An observational cohort study of replicate faecal immunochemical tests in symptomatic two-week wait patients
Authors: Farkas N , O’Brien J , Whyte M , Jourdan I , Rockall T , Benton S 
Published: May 2023

Abstract

Introduction
Triage of patients with suspected colorectal cancer (CRC) utilises a single faecal immunochemical test (FIT) at a defined threshold. Limited evidence exists regarding whether replicate FIT improves the positive and negative predictive value in symptomatic patients. This study examines two-week wait (TWW) patients undergoing replicate FIT. Primary aim is to assess two FITs and CRC/serious bowel disease. Secondary aims are to determine correlation and utility of replicate FIT.

Methods
TWW patients carried out one additional FIT during COVID-19 pandemic. FIT 1 and FIT 2 (the replicate sample) were analysed in relation to symptoms, diagnoses, investigations, future colonoscopy and missed CRC. Study period was 01/03/2020-31/07/2020. Three subgroups were compared; double positive (&gt;10μg Hb/g faeces), double negative, and discordant FIT (one positive).

Results
111 patients had replicate FIT (50 male, 61 female). 43 (38.7%) patients had double negative, 32 (28.8%) double positive and 36 (32.4%) had discordant FITs. Median time between FITs was 14 days (IQR=11 to 19). 83% of double positive patients underwent colonoscopy/virtual colonoscopy (61% in double negative patients). Six CRC and one high-risk polyp were in double positive patients (none in other groups). One discordant patient was not investigated and a CRC missed.

Conclusion
Replicate FIT as a triage strategy appears most effective where both FITs are negative. CRC risk is low when FIT results are discordant. Double negative FITs are reassuring given benign associated diagnoses, or for patients where endoscopic investigation is high-risk. Larger studies are required to evaluate discordant FITs, enabling refinement of urgent investigation pathways.
O138 Diagnostic and prognostic factors associated with faecal haemoglobin concentration in a symptomatic cohort
Authors: Farkas N , O'Brien J , Norman J , Steinke J , Yu K , Jourdan I , Rockall T , Benton S 
Published: May 2023

Abstract

Introduction
There is limited evidence regarding FIT and colorectal cancer (CRC) site, stage, grade and anaemia in the symptomatic cohort. Primary aim is to determine whether an association exists between FIT (analysed with OC-Sensor™ Pledia) and these diagnostic/prognostic factors. Secondary aim was to compare continuous versus categorical FIT, to determine the difference when reporting to upper limit of quantification (some centres do not report FIT &gt;200 (μg Hb/g faeces)).

Methods
Symptomatic two-week wait CRC with FIT were grouped into thresholds (&lt;10, 10-200 and &gt;200) and analysed using Chi-squared test. Mann-Whitney U test (p≤0.05) compared median FIT in sex, stage, grade and site (right-sided (R-CRC): caecum to transverse colon/ left-sided (L-CRC): splenic flexure to rectum). Pearson's correlation compared FIT and continuous variables (haemoglobin, mean corpuscular volume and ferritin).

Results
114 patients (57F:57M); 46 R-CRC (FIT=113) vs 68 L-CRC (FIT=342) (p=0.07), 69 moderately differentiated CRC (FIT=183) vs 29 poorly differentiated (FIT=866) (p=0.004). 35 early stage (T1/2) (FIT=170) vs 79 advanced (T3/4) (FIT=200) (p=0.06). Ferritin &lt;30ug/L correlated with higher FIT (p=0.18). When grouped into FIT thresholds, each association became less significant.

Conclusion
Left-sided, poorly differentiated and advanced stage CRC is associated with higher FIT. There appears benefit in reporting FIT to the upper limit of quantification in symptomatic patients, as this may allow greater differentiation and earlier investigation of those with adverse CRC prognostic features. The presence of low ferritin reinforces the diagnostic value of elevated FIT. Given these findings, FIT may have a role in risk stratification for CRC beyond diagnosis alone.
O140 Delorme vs. Altemeier: a systematic review and meta-analysis comparing the common perineal procedures for rectal prolapse
Authors: Bhattacharya P , Zaman S , Hussain M I , Peravali R 
Published: May 2023

Abstract

Introduction
Rectal prolapse is a particularly distressing condition for patients, and there is no consensus yet as to the best surgical option for treatment. In this systematic review and meta-analysis we compared the outcomes for the two most commonly employed perineal operations for rectal prolapse – Delorme's and Altemeier's procedure.

Methods
A systematic search of multiple electronic databases was conducted. Peri- and post-operative outcomes following Delorme's and Altemeier's procedures were extracted. Primary outcomes included recurrence rate, anastomotic leak rate, and length of hospital stay. The secondary outcomes were operation time, volume of blood loss and length of hospital stay. Revman 5.3 was used to perform statistical analysis.

Results
10 studies including a total of 605 patients were selected. Recurrence (OR: 0.66; 95% CI [0.44–0.99], P= 0.05) and anastomotic leak (RD: 0.05; 95% CI [0.00–0.09], P= 0.03) were found to be significantly less in the Altemeier group than in the Delorme group. However on subgroup analysis Altemeiers with plasty (perineoplasty or levatoroplasty) failed to show significant differences in comparison to Delorme's. Hospital stay was significantly more after Altemeiers procedure than after Delorme procedure (MD: 3.05, 95% CI [0.95–5.51], p=0.004). No significant difference was found with respect to operative time, intra operative blood loss and mortality rates.

Conclusion
Our study indicates that between the two common perineal procedures, Altemeier's operation has better outcomes. Future high quality RCTs with long follow up are required to corroborate these findings.
O151 A comparison of pathological TNM 7 with TNM 8 staging for pancreatic ductal adenocarcinoma and distal cholangiocarcinoma
Authors: Mohammad F , Hanks M , Kandiah K , Wong T , Adiamah A , Zaitoun A M , Lobo D N 
Published: May 2023

Abstract

Background
The 8th edition of the TNM (tumour, nodes and metastasis) staging system was introduced in 2016 to improve the prognostic prediction of pancreatic ductal adenocarcinoma (PDAC). However, its superiority over the previous edition remains uncertain. This study evaluated the prognostic impact of TNM 7 with TNM 8 staging in patients with PDAC and distal cholangiocarcinoma.

Methods
A retrospective cohort study was conducted using electronic healthcare databases at a tertiary hepatobiliary centre in the UK. Kaplan-Meier survival curves were used to evaluate the prognostic prediction of TNM 7 and TNM 8 staging. The concordance index was calculated to assess the discriminatory power of both systems. Crosstabulation of T, N and overall staging was performed to determine which staging system stratified patients more effectively.

Results
The study identified 194 patients and found the overall median survival after resection to be 1.86 years. The concordance index for TNM 7 [0.634; 95% confidence intervall(CI) 0.586-0.682)], was similar to TNM 8 (0.633; 95% CI 0.584-0.683). TNM 8 showed improved stratification of patients for the T (p=0.001), N (p=0.001) classifications and overall staging system (p=0.001). However, in TNM 8, the new N2 stage had a similar survival prediction to N1.

Conclusion
There was no significant difference in the prognostic prediction between the TNM 7 and TNM 8 systems for PDAC and distal cholangiocarcinoma. While TNM 8 improved patient stratification across T staging, our findings found the introduction of the N2 staging to be unnecessary as its survival prediction was comparable to N1.
O156 A systematic review of ethical considerations in paediatric bariatric surgery
Authors: Shah A , Kumar N S 
Published: May 2023

Abstract

Introduction
With childhood obesity prevalence increasing rapidly, bariatric surgery is being given greater consideration in the paediatric population. Paucity of long-term evidence, physical and emotional risks, and reliance on parental decision-making are factors constituting this moral complexity, forming debate around eligibility and timing of offering the procedure. Consequently, a systematic review was conducted to evaluate ethical considerations.

Methods
All relevant synonyms of paediatric, bariatric surgery and ethics were used to identify papers for inclusion in the systematic review and reference lists were scanned. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were adhered to.

Results
10 papers were included. A key ethical dilemma frequently explored was the issue of consent, and ensuring the child is at the forefront of the decision. Paediatric bariatric surgery causes controversy as children are exposed to surgical risk early in life, and thus prolonged preventative measures are encouraged with the aim to mitigate obesity by adulthood causing unnecessary harm. Children without a strong support network have additional obesity risk, whereby withholding surgery may be viewed as inequitable and non-beneficent. There is also conflict between delaying surgery until the child is Fraser-competent versus increased complication risk.

Conclusion
Further evidence to guide assessment criteria are needed to facilitate informed consent. Post-operative support should be audited, with inclusive care and sustained health outcomes monitored. Although preventative methods are important in the paediatric population, clinicians must not discriminate against those for whom it proves ineffective, with bariatric surgery being a last resort for high-risk obese patients.
O162 Can digital microscopes be used in microsurgery simulation training?
Authors: Awad L , Langridge B , Butler P 
Published: May 2023

Abstract

Introduction
Surgical education has seen a transition in the delivery of training, with increased use of online platforms to facilitate remote learning. Simulation provides a safe training environment, that can be accessed by a wider group, and at a lower cost compared to many ex-vivo courses. Microsurgical skills are difficult to acquire, and continuous practice is necessary to improve. Our goals are to compare commercially available digital microscopes against a standard binocular microscope and review their suitability for bench model simulation.

Methods
Data was collected for three commercially available digital microscopes, and a binocular table microscope. Data obtained included physicial properties, cost and a subjective assessment of their surgical performance via an 11 criteria questionnaire, graded with a 5-point scale. Results of the commercial microscopes were compared with the binocular microscope using the Kruskall Wallis test.

Results
The questionnaire was completed by 21 participants ranging from senior ENT/Plastic Surgery consultants to core surgical trainees. Digital microscopes were more affordable and convenient for trainees. The Pancellant Digital Microscope performed the poorest, with trainees commenting on its unsuitability for surgical practice. The Plugable USB Microscope was rated most like the binocular table microscope. Depth of field was shallow in all digital microscopes.

Conclusion
With the increasing role of remote learning and simulation training in surgical education, the Plugable USB digital microscope can provide a cheaper, more accessible alternative for junior trainees, in their pursuit of microsurgical skill acquisition.
P12 Patient-specific automated cerebrospinal fluid pressure control to augment spinal wound closure: a case series using LiquoGuard®
Authors: Khan D , Tariq K , Lee K , Dyson E , Russo V , Watkins L , Russo A 
Published: May 2023

Abstract

Introduction
Post-operative spinal cerebrospinal fluid (CSF) leaks are a common and potentially serious surgical complication. The management of intra- and post-operative leaks is heterogeneous. Numerous studies advocate for dural repair and CSF diversion. The LiquoGuard7 allows automated and precise CSF pressure and volume control, with the calculation of patient-specific biometrics. We sought to summarize our experience with patient-specific CSF automated drainage with layered spinal wound closure.

Methods
This single-centre case series included patients undergoing complex spinal surgery where: 1) a high-flow intra- and/or postoperative CSF leak was expected and 2) concurrent CSF diversion was performed via lumbar drain attached to a LiquoGuard7®. CSF diversion was tailored to calculated CSF production rates and other case factors to maintain a neutral pressure across the operative site.

Results
Three patients were included, with a variety of pathologies (T7/T8 disc prolapse; T8-T9; T4-T5 metastatic spinal cord compression). The first two patients underwent CSF diversion to prevent post-op CSF leak, whilst case 3 required this in response to post-op CSF leak. CSF hyperproduction (140-150ml/hr) was evident in all cases. With patient-specific CSF diversion regimes, no cases required further intervention for CSF fistulae repair (including for pleural CSF effusion), wound breakdown or infection.

Conclusion
Automated patient-specific cerebrospinal fluid drainage may have a role in the closure of complex spinal wounds with high-flow CSF leaks, with a smaller risk profile than traditional manual drainage. Further larger studies are needed to explore the comparative benefits and cost-effectiveness of these devices.
P18 Components of the ideal spoke vascular surgery unit
Authors: Faisal M J , Baker D , Agu O , Benaragama K S 
Published: May 2023

Abstract

Introduction
The ‘Hub and Spoke’ system consists of a leading unit that offers all services (Hub), supported by peripheral units providing less extensive services (Spokes). Cases requiring more complex interventions are often transferred from Spoke Units to the Hub. We wish to shed light on the factors that comprise an ideal Spoke Unit.

Methods
We did a retrospective review of the Peripheral arterial and Venous cases at our Spoke unit, and analysed patient records, took note of the contributions of various specialities and teams within the unit, allowing us to provide optimal care.

Results
We found that over an 8-month period (5th April 2022- 1st December 2022), the spoke unit undertook 105 lower limb venous procedures, and 55 arterial revascularisations, as day cases. This was possible due to the support we have from the podiatrists, vascular scientists, interventional radiologists, anaesthesiologists, physiotherapists, clinical specialist nurses and allied nursing teams as well as vascular unit managers. In cases where the hub may be overburdened, the Spoke unit can provide support by managing patients within their domain. Our main Hub Unit has an estimated capacity of 70-80 patients per week at any given time. When referrals to the Hub exceed the capacity, the spoke unit supports them to ensure optimal patient care and avoid physician burnout.

Conclusion
Having a strong multidisciplinary team contributes to an ideal spoke unit. Creating the ideal spoke unit is essential to optimise patient healthcare within a Hub and Spoke system, but also in preventing physician burnout.