Predicting Inadequate Weight Loss After Bariatric Surgery: Derivation and Validation of a Four Factor Model.

INTRODUCTION: Weight loss following bariatric surgery is variable and predicting inadequate weight loss is required to help select patients for bariatric surgery. The aim of the present study was to determine variables associated with inadequate weight loss and to derive and validate a predictive model. METHODS: All patients who underwent laparoscopic sleeve gastrectomy and Roux-en-Y gastrectomy (2008-2022) in a tertiary referral centre were followed up prospectively. Inadequate weight loss was defined as excess weight loss (EWL) < 50% by 24 months. A top-down approach was performed using multivariate logistic regression and then internally validated using bootstrapping. Patients were categorised into risk groups. RESULTS: A total of 280 patients (median age, 49 years; M:F, 69:211) were included (146 LSG; 134 LRYGB). At 24 months, the median total weight loss was 30.9% and 80.0% achieved EWL ≥ 50% by 24 months. Variables associated with inadequate weight loss were T2DM (OR 2.42; p = 0.042), age 51-60 (OR 1.93, p = 0.006), age > 60 (OR 4.93, p < 0.001), starting BMI > 50 kg/m² (OR 1.93, p = 0.037) and pre-operative weight loss (OR 3.51; p = 0.036). The validation C-index was 0.75 (slope = 0.89). Low, medium and high-risk groups had a 4.9%, 16.7% and 44.6% risk of inadequate weight loss, respectively. CONCLUSIONS: Inadequate weight loss can be predicted using a four factor model which could help patients and clinicians in decision-making for bariatric surgery.

Optimising the use of colonoscopy to improve risk stratification for colorectal cancer in symptomatic patients: A decision-curve analysis.

OBJECTIVES: Pressured healthcare resources make risk stratification and patient prioritisation fundamental issues for the investigation of colorectal cancer (CRC) in symptomatic patients. The present study uses machine learning algorithms and decision strategies to improve the appropriate use of colonoscopy. DESIGN: All symptomatic patients in a single health board (2018-2021) proceeding to colonoscopy to investigate for CRC were included. Machine learning algorithms (NeuralNetwork, randomForest, Logistic regression, Naïve-Bayes and Adaboost) were used to risk-stratify patients for CRC using demographics, symptoms, quantitative faecal immunochemical test (qFIT) and haematological tests. Decision curve analyses were performed to determine the optimal decision strategies. RESULTS: 3776 patients were included (median age, 65; M:F,0.9:1.0) and CRC was identified in 217 patients (5.7%). qFIT > 400 µg Hb/g was the most important variable (%IncMSE = 78.5). RandomForrest had the highest area under curve (0.91) and accuracy (0.80) for CRC. When utilising decision curve analysis (DCA), 30%, 46% and 54% of colonoscopies were saved at accepted CRC probabilities of 1%, 2% and 3%, respectively. RandomForrest modelling had superior net clinical benefit compared to default colonoscopy strategies. CONCLUSIONS: MLA-derived decision strategies that account for patient and referrer risk preference reduce colonoscopy demand and carry net clinical benefit compared to default colonoscopy strategies.

The effects of previous abdominal surgery and the utilisation of modified access techniques on the operative difficulty and outcomes of laparoscopic cholecystectomy and bile duct exploration.

BACKGROUND: Early reports suggested that previous abdominal surgery was a relative contraindication to laparoscopic cholecystectomy (LC) on account of difficulty and potential access complications. This study analyses different types/systems of previous surgery and locations of scars and how they affect access difficulties. As modified access techniques to minimise risk of complications are under-reported the study details and evaluates them. METHOD: Prospectively collected data from consecutive LC and common bile duct explorations (LCBDE) performed by a single surgeon over 30 years was analysed. Previous abdominal surgery was documented and peri-operative outcomes were compared with patients who had no previous surgery using Chi-squared analysis. RESULTS: Of 5916 LC and LCBDE, 1846 patients (31.2%) had previous abdominal surgery. The median age was 60 years. Those with previous surgery required more frequent duodenal (RR 1.07; p = 0.023), hepatic flexure (RR 1.11; p = 0.043) and distal adhesiolysis (RR 3.57; p < 0.001) and had more access related bowel injuries (0.4% vs. 0.0%; p < 0.001). Previous upper gastrointestinal and biliary surgery had the highest rates of adhesiolysis (76.3%), difficult cystic pedicles (58.8%), fundus-first approach (7.2%), difficulty grades (64.9% Grades 3-5) and utilisation of abdominal drains (71.1%). Previous open surgery resulted in longer operative time compared to previous laparoscopic procedures (65vs.55 min; p < 0.001), increased difficulty of pedicle dissection (42.4% vs. 36.0%; p < 0.05) and required more duodenal, hepatic flexure and distant adhesiolysis (p < 0.05) and fundus-first dissection (4% vs 2%; p < 0.05). Epigastric and supraumbilical access and access through umbilical and other hernias were used in 163 patients (8.8%) with no bowel complications. CONCLUSION: The risks of access and adhesiolysis in patients with previous abdominal scars undergoing biliary surgery are dependent on the nature of previous surgery. Previous open, upper gastrointestinal and biliary surgery carried the most significant risks. Modified access techniques can be adopted to safely mitigate these risks.

Precursor Epithelial Subtypes of Adenocarcinoma Arising from Intraductal Papillary Mucinous Neoplasms (A-IPMN): Clinicopathological Features, Recurrence and Response to Adjuvant Chemotherapy.

BACKGROUND: The clinico-oncological outcomes of precursor epithelial subtypes of adenocarcinoma arising from intraductal papillary mucinous neoplasms (A-IPMN) are limited to small cohort studies. Differences in recurrence patterns and response to adjuvant chemotherapy between A-IPMN subtypes are unknown. METHODS: Clincopathological features, recurrence patterns and long-term outcomes of patients undergoing pancreatic resection (2010-2020) for A-IPMN were reported from 18 academic pancreatic centres worldwide. Precursor epithelial subtype groups were compared using uni- and multivariate analysis. RESULTS: In total, 297 patients were included (median age, 70 years; male, 78.9%), including 54 (18.2%) gastric, 111 (37.3%) pancreatobiliary, 80 (26.9%) intestinal and 52 (17.5%) mixed subtypes. Gastric, pancreaticobiliary and mixed subtypes had comparable clinicopathological features, yet the outcomes were significantly less favourable than the intestinal subtype. The median time to recurrence in gastric, pancreatobiliary, intestinal and mixed subtypes were 32, 30, 61 and 33 months. Gastric and pancreatobiliary subtypes had worse overall recurrence (p = 0.048 and p = 0.049, respectively) compared with the intestinal subtype but gastric and pancreatobiliary subtypes had comparable outcomes. Adjuvant chemotherapy was associated with improved survival in the pancreatobiliary subtype (p = 0.049) but not gastric (p = 0.992), intestinal (p = 0.852) or mixed subtypes (p = 0.723). In multivariate survival analysis, adjuvant chemotherapy was associated with a lower likelihood of death in pancreatobiliary subtype, albeit with borderline significance [hazard ratio (HR) 0.56; 95% confidence interval (CI) 0.31-1.01; p = 0.058]. CONCLUSIONS: Gastric, pancreatobiliary and mixed subtypes have comparable recurrence and survival outcomes, which are inferior to the more indolent intestinal subtype. Pancreatobiliary subtype may respond to adjuvant chemotherapy and further research is warranted to determine the most appropriate adjuvant chemotherapy regimens for each subtype.

Predictors of long-term survival after resection of adenocarcinoma arising from intraductal papillary mucinous neoplasm and derivation of a prognostic model: An international multicenter study (ADENO-IPMN study).

BACKGROUND: Predictors of long-term survival after resection of adenocarcinoma arising from intraductal papillary mucinous neoplasms are unknown. This study determines predictors of long-term (>5 years) disease-free survival and recurrence in adenocarcinoma arising from intraductal papillary mucinous neoplasms and derives a prognostic model for disease-free survival. METHODS: Consecutive patients who underwent pancreatic resection for adenocarcinoma arising from intraductal papillary mucinous neoplasms in 18 academic pancreatic centers in Europe and Asia between 2010 to 2017 with at least 5-year follow-up were identified. Factors associated with disease-free survival were determined using Cox proportional hazards model. Internal validation was performed, and discrimination and calibration indices were assessed. RESULTS: In the study, 288 patients (median age, 70 years; 52% male) were identified; 140 (48%) patients developed recurrence after a median follow-up of 98 months (interquartile range, 78.4-123), 57 patients (19.8%) developed locoregional recurrence, and 109 patients (37.8%) systemic recurrence. At 5 years after resection, the overall and disease-free survival was 46.5% (134/288) and 35.0% (101/288), respectively. On Cox proportional hazards model analysis, multivisceral resection (hazard ratio, 2.20; 95% confidence interval, 1.06-4.60), pancreatic tail location (hazard ratio, 2.34; 95% confidence interval, 1.22-4.50), poor tumor differentiation (hazard ratio, 2.48; 95% confidence interval, 1.10-5.30), lymphovascular invasion (hazard ratio, 1.74; 95% confidence interval, 1.06-2.88), and perineural invasion (hazard ratio, 1.83; 95% confidence interval, 1.09-3.10) were negatively associated with long-term disease-free survival. The final predictive model incorporated 8 predictors and demonstrated good predictive ability for disease-free survival (C-index, 0.74; calibration, slope 1.00). CONCLUSION: A third of patients achieve long-term disease-free survival (>5 years) after pancreatic resection for adenocarcinoma arising from intraductal papillary mucinous neoplasms. The predictive model developed in the current study can be used to estimate the probability of long-term disease-free survival.

Adjuvant chemotherapy for adenocarcinoma arising from intraductal papillary mucinous neoplasia: multicentre ADENO-IPMN study.

BACKGROUND: The clinical impact of adjuvant chemotherapy after resection for adenocarcinoma arising from intraductal papillary mucinous neoplasia is unclear. The aim of this study was to identify factors related to receipt of adjuvant chemotherapy and its impact on recurrence and survival. METHODS: This was a multicentre retrospective study of patients undergoing pancreatic resection for adenocarcinoma arising from intraductal papillary mucinous neoplasia between January 2010 and December 2020 at 18 centres. Recurrence and survival outcomes for patients who did and did not receive adjuvant chemotherapy were compared using propensity score matching. RESULTS: Of 459 patients who underwent pancreatic resection, 275 (59.9%) received adjuvant chemotherapy (gemcitabine 51.3%, gemcitabine-capecitabine 21.8%, FOLFIRINOX 8.0%, other 18.9%). Median follow-up was 78 months. The overall recurrence rate was 45.5% and the median time to recurrence was 33 months. In univariable analysis in the matched cohort, adjuvant chemotherapy was not associated with reduced overall (P = 0.713), locoregional (P = 0.283) or systemic (P = 0.592) recurrence, disease-free survival (P = 0.284) or overall survival (P = 0.455). Adjuvant chemotherapy was not associated with reduced site-specific recurrence. In multivariable analysis, there was no association between adjuvant chemotherapy and overall recurrence (HR 0.89, 95% c.i. 0.57 to 1.40), disease-free survival (HR 0.86, 0.59 to 1.30) or overall survival (HR 0.77, 0.50 to 1.20). Adjuvant chemotherapy was not associated with reduced recurrence in any high-risk subgroup (for example, lymph node-positive, higher AJCC stage, poor differentiation). No particular chemotherapy regimen resulted in superior outcomes. CONCLUSION: Chemotherapy following resection of adenocarcinoma arising from intraductal papillary mucinous neoplasia does not appear to influence recurrence rates, recurrence patterns or survival.

Long-term Outcomes following Resection of Adenocarcinoma Arising from Intraductal Papillary Mucinous Neoplasm (A-IPMN) versus Pancreatic Ductal Adenocarcinoma (PDAC): A Propensity-score Matched Analysis.

OBJECTIVE: The aim of the present study was to compare long-term post-resection oncological outcomes between A-IPMN and PDAC. SUMMARY BACKGROUND DATA: Knowledge of long term oncological outcomes (e.g recurrence and survival data) comparing between adenocarcinoma arising from intraductal papillary mucinous neoplasms (A-IPMN) and pancreatic ductal adenocarcinoma (PDAC) is scarce. METHODS: Patients undergoing pancreatic resection (2010-2020) for A-IPMN were identified retrospectively from 18 academic pancreatic centres and compared with PDAC patients from the same time-period. Propensity-score matching (PSM) was performed and survival and recurrence were compared between A-IPMN and PDAC. RESULTS: 459 A-IPMN patients (median age,70; M:F,250:209) were compared with 476 PDAC patients (median age,69; M:F,262:214). A-IPMN patients had lower T-stage, lymphovascular invasion (51.4%vs. 75.6%), perineural invasion (55.8%vs. 71.2%), lymph node positivity (47.3vs. 72.3%) and R1 resection (38.6%vs. 56.3%) compared to PDAC(P<0.001). The median survival and time-to-recurrence for A-IPMN versus PDAC were 39.0 versus19.5months (P<0.001) and 33.1 versus 14.8months (P<0.001), respectively (median follow-up,78 vs.73 months). Ten-year overall survival for A-IPMN was 34.6%(27/78) and PDAC was 9%(6/67). A-IPMN had higher rates of peritoneal (23.0 vs. 9.1%, P<0.001) and lung recurrence (27.8% vs. 15.6%, P<0.001) but lower rates of locoregional recurrence (39.7% vs. 57.8%; P<0.001). Matched analysis demonstrated inferior overall survival (P=0.005), inferior disease-free survival (P=0.003) and higher locoregional recurrence (P<0.001) in PDAC compared to A-IPMN but no significant difference in systemic recurrence rates (P=0.695). CONCLUSIONS: PDACs have inferior survival and higher recurrence rates compared to A-IPMN in matched cohorts. Locoregional recurrence is higher in PDAC but systemic recurrence rates are comparable and constituted by their own distinctive site-specific recurrence patterns.

Intensive pre-operative information course (IPIC) and pre-operative weight loss results in long-term sustained weight loss following bariatric surgery: 11 years results from a tertiary referral centre.

INTRODUCTION: Outcomes of long-term (5-10-year) weight loss have not been investigated thoroughly and the role of pre-operative weight loss on long-term weight loss, among other factors, are unknown. Our regional bariatric service introduced a 12 week intensive pre-operative information course (IPIC) to optimise pre-operative weight loss and provide education prior to bariatric surgery. The present study determines the effect of pre-operative weight loss and an intense pre-operative information course (IPIC), on long-term weight outcomes and sustained weight loss post-bariatric surgery. METHODS: Data were collected prospectively from a bariatric center (2008-2022). Excess weight loss (EWL) ≥ 50% and ≥ 70% were considered outcome measures. Survival analysis and logistic regression identified variables associated with overall and sustained EWL ≥ 50% and ≥ 70%. RESULTS: Three hundred thirty-nine patients (median age, 49 years; median follow-up, 7 years [0.5-11 years]; median EWL%, 49.6%.) were evaluated, including 158 gastric sleeve and 161 gastric bypass. During follow-up 273 patients (80.5%) and 196 patients (53.1%) achieved EWL ≥ 50% and ≥ 70%, respectively. In multivariate survival analyses, pre-operative weight loss through IPIC, both < 10.5% and > 10.5% EWL, were positively associated with EWL ≥ 50% (HR 2.23, p < 0.001) and EWL ≥ 70% (HR 3.24, p < 0.001), respectively. After a median of 6.5 years after achieving EWL50% or EWL70%, 56.8% (154/271) had sustained EWL50% and 50.6% (85/168) sustained EWL70%. Higher pre-operative weight loss through IPIC increased the likelihood of sustained EWL ≥ 50% (OR, 2.36; p = 0.013) and EWL ≥ 70% (OR, 2.03; p = 0.011) at the end of follow-up. CONCLUSIONS: IPIC and higher pre-operative weight loss improve weight loss post-bariatric surgery and reduce the likelihood of weight regain during long-term follow-up.

Opioid analgesia and severity of acute pancreatitis: An international multicentre cohort study on pain management in acute pancreatitis.

BACKGROUND: The effect of analgesic modalities on short-term outcomes in acute pancreatitis remains unknown. However, preclinical models have raised safety concerns regarding opioid use in patients with acute pancreatitis. OBJECTIVE: This study aimed to assess the association between analgesics, particularly opioids, and severity and mortality in hospitalised patients with acute pancreatitis. METHODS: This prospective multicentre cohort study recruited consecutive patients admitted with a first episode of acute pancreatitis between April 1 and 30 June 2022, with a 1-month follow-up. Data on aetiology, clinical course, and analgesic treatment were collected. The primary outcome was the association between opioid analgesia and acute pancreatitis severity, which was analysed using univariate and multivariate analyses. RESULTS: Among a total of 1768 patients, included from 118 centres across 27 countries, 1036 (59%) had opioids administered on admission day, and 167 (9%) received opioids after admission day. On univariate analysis, moderately severe or severe acute pancreatitis was associated with male sex, Asian ethnicity, alcohol aetiology, comorbidity, predicted severe acute pancreatitis, higher pain scores, longer pain duration and opioid treatment (all p < 0.001). On multivariate analysis, comorbidity, alcohol aetiology, longer pain duration and higher pain scores increased the risk of moderately severe or severe acute pancreatitis (all p < 0.001). Furthermore, opioids administered after admission day (but not on admission day) doubled the risk of moderately severe or severe disease (OR 2.07 (95% CI, 1.29-3.33); p = 0.003). Opioid treatment for 6 days or more was an independent risk factor for moderately severe or severe acute pancreatitis (OR 3.21 (95% CI, 2.16-4.79; p < 0.001). On univariate analysis, longer opioid duration was associated with mortality. CONCLUSION: Opioid treatment increased the risk of more severe acute pancreatitis only when administered after admission day or for 6 days or more. Future randomised studies should re-evaluate whether opioids might be safe in acute pancreatitis.

A multicentre prospective evaluation of health-related quality of life and patient related outcomes in pancreatic and peripancreatic cancer: PROMCAN study.

BACKGROUND: The temporal evolution of HRQoL and the importance of other PROs to patients, following resection for pancreatic and peripancreatic malignancy remains unexplored. METHODS: Patients undergoing pancreatic resection between 2021 and 2022 were enrolled from 2 UK HPB centres. Patients completed the EORTC QLQ-C30, QLQ-PAN26 tools and rated 56 PROs preoperatively (T1), at discharge (T2), 6-weeks (T3), 3-months (T4) and 6-months (T5) postoperatively. ANOVA followed by post-hoc analysis was used to examine patterns in HRQoL through time. Multivariable ANOVA was used to identify impact of clinical factors on HRQoL. RESULTS: 63 patients were recruited [median age, 72 (IQR 41-85); 39/63 male]. Physical functioning declined from 70.4 (26.2) at T1 to 53.5 (20.9) at T2 (p = 0.016). Global QoL score increased significantly from 41.0 (23.0) at T2 to 60.0 (26.1) at T5 (p = 0.007), as did role functioning [21.1 (27.9) at T2 to 59.4 (32.8) at T5, p < 0.001]. Chemotherapy status and the postoperative complications did not significantly change HRQoL. General QoL and health were the only PROs rated as 'very important' (scores 7-9) by more than 80 % of participants at five time-points. CONCLUSION: Recuperation of HRQoL measures is seen at 6-months postoperative and was not affected by chemotherapy or postoperative complications. Notably, PROs important to patients varied over time.

Validation of the updated Bosniak classification (2019) in pathologically confirmed CT-categorised cysts.

INTRODUCTION: The updated Bosniak classification in 2019 (v2019) addresses vague imaging terms and revises the criteria with the intent to categorise a higher proportion of cysts in lower-risk groups and reduce benign cyst resections. The aim of the present study was to compare the diagnostic accuracy and inter-observer agreement rate of the original (v2005) and updated classifications (v2019). METHOD: Resected/biopsied cysts were categorised according to Bosniak classifications (v2005 and v2019) and the diagnostic accuracy was assessed with reference to histopathological analysis. The inter-observer agreement of v2005 and v2019 was determined. RESULTS: The malignancy rate of the cohort was 83.6% (51/61). Using v2019, a higher proportion of malignant cysts were categorised as Bosniak ≥ III (88.2% vs 84.3%) and a significantly higher percentage were categorised as Bosniak IV (68.9% vs 47.1%; p = 0.049) in comparison to v2005. v2019 would have resulted in less benign cyst resections (13.5% vs 15.7%). Calcified versus non-calcified cysts had lower rates of malignancy (57.1% vs 91.5%; RR,0.62; p = 0.002). The inter-observer agreement of v2005 was higher than that of v2019 (kappa, 0.70 vs kappa, 0.43). DISCUSSION: The updated classification improves the categorisation of malignant cysts and reduces benign cyst resection. The low inter-observer agreement remains a challenge to the updated classification system.

Biogenesis, inheritance, and 3D ultrastructure of the microsporidian mitosome.

During the reductive evolution of obligate intracellular parasites called microsporidia, a tiny remnant mitochondrion (mitosome) lost its typical cristae, organellar genome, and most canonical functions. Here, we combine electron tomography, stereology, immunofluorescence microscopy, and bioinformatics to characterise mechanisms of growth, division, and inheritance of this minimal mitochondrion in two microsporidia species (grown within a mammalian RK13 culture-cell host). Mitosomes of Encephalitozoon cuniculi (2-12/cell) and Trachipleistophora hominis (14-18/nucleus) displayed incremental/non-phasic growth and division and were closely associated with an organelle identified as equivalent to the fungal microtubule-organising centre (microsporidian spindle pole body; mSPB). The mitosome-mSPB association was resistant to treatment with microtubule-depolymerising drugs nocodazole and albendazole. Dynamin inhibitors (dynasore and Mdivi-1) arrested mitosome division but not growth, whereas bioinformatics revealed putative dynamins Drp-1 and Vps-1, of which, Vps-1 rescued mitochondrial constriction in dynamin-deficient yeast (Schizosaccharomyces pombe). Thus, microsporidian mitosomes undergo incremental growth and dynamin-mediated division and are maintained through ordered inheritance, likely mediated via binding to the microsporidian centrosome (mSPB).

Risk of Recurrence after Surgical Resection for Adenocarcinoma Arising from Intraductal Papillary Mucinous Neoplasia (IPMN) with Patterns of Distribution and Treatment: An International, Multicentre, Observational Study.

OBJECTIVE: This international multicentre cohort study aims to identify recurrence patterns and treatment of first and second recurrence in a large cohort of patients after pancreatic resection for adenocarcinoma arising from IPMN. SUMMARY BACKGROUND DATA: Recurrence patterns and treatment of recurrence post resection of adenocarcinoma arising from IPMN are poorly explored. METHOD: Patients undergoing pancreatic resection for adenocarcinoma from IPMN between January 2010 to December 2020 at 18 pancreatic centres were identified. Survival analysis was performed by the Kaplan-Meier log rank test and multivariable logistic regression by Cox-Proportional Hazards modelling. Endpoints were recurrence (time-to, location, and pattern of recurrence) and survival (overall survival and adjusted for treatment provided). RESULTS: Four hundred and fifty-nine patients were included (median, 70 y; IQR, 64-76; male, 54 percent) with a median follow-up of 26.3 months (IQR, 13.0-48.1 mo). Recurrence occurred in 209 patients (45.5 percent; median time to recurrence, 32.8 months, early recurrence [within 1 y], 23.2 percent). Eighty-three (18.1 percent) patients experienced a local regional recurrence and 164 (35.7 percent) patients experienced distant recurrence. Adjuvant chemotherapy was not associated with reduction in recurrence (HR 1.09;P=0.669) One hundred and twenty patients with recurrence received further treatment. The median survival with and without additional treatment was 27.0 and 14.6 months (P<0.001), with no significant difference between treatment modalities. There was no significant difference in survival between location of recurrence (P=0.401). CONCLUSION: Recurrence after pancreatic resection for adenocarcinoma arising from IPMN is frequent with a quarter of patients recurring within 12 months. Treatment of recurrence is associated with improved overall survival and should be considered.

The impact of surgical set-up of endoscopic two surgeon four hand anterior skull base surgeries on surgeons' ergonomics.

BACKGROUND: The impact of different surgical set-ups of endoscopic two surgeon four hand anterior skull base surgeries on surgeons' ergonomics remain unclear. This study aims to explore the effect of surgeon, patient and surgical screen positioning on surgeons' ergonomics using the Rapid Entire Body Assessment (REBA) tool. METHODS: A total of 20 different surgical positions of anterior skull base surgery were simulated and the ergonomic impact on surgeons' neck, truck, leg and wrist were measured using the validated Rapid Entire Body Assessment (REBA) tool. To investigate the ergonomic effect of different surgical setups, the operating surgeon, assisting surgeon, patient head, camera and screen positions were positioned differently in each surgical position. RESULTS: The lowest REBA Score recorded is 3 whereas the highest score is 8. The REBA scores for the majority of positions are 3 highlighting that these positions are ergonomically favorable. Position 12 is the least ergonomically favorable position with a total REBA score of 19. In this position, operating surgeon is positioned to the right of the patient, assisting surgeon to the left of patient, patient head in central position with camera held by operating surgeon and one screen is placed to the right of patient. Positions 13 and 17 are the most ergonomically favorable positions with a total REBA score of 12. In these positions, the patient's head is positioned to the center, two screens were utilized, and the surgeons were positioned on either side of the patient. The utilization of 2 screens with a central patient head position with the surgeons placed on either side of the patient contribute towards a more ergonomically state in these positions. CONCLUSIONS: Certain positional behaviors are better at reducing musculoskeletal injury risk when compared to other. Positions with two screens and central head positions are more favourable ergonomically and surgeons should consider this set-up to reduce musculoskeletal injuries during anterior skull base surgery.

Defining Prolonged Length of Stay (PLOS) Following Elective Laparoscopic Cholecystectomy and Derivation of a Preoperative Risk Score to Inform Resource Utilization, Risk Stratification, and Patient Consent.

OBJECTIVE: The present study defines prolonged length of stay (PLOS) following elective laparoscopic cholecystectomy (LC) and its relationship with perioperative morbidity. A preoperative risk tool to predict PLOS is derived to inform resource utilization, risk stratification and patient consent. BACKGROUND: Surgical candidates for elective LC are a heterogeneous group at risk of various perioperative adverse outcomes. Preoperative recognition of high-risk patients for PLOS has implications on feasibility for day surgery, resource utilization, preoperative risk stratification, and patient consent. METHODS: Data for all patients who underwent elective LC between January 2015 and January 2020 across 3 surgical centers (1 tertiary referral center and 2 satellite units) in 1 health board were collected retrospectively (n=2166). The optimal cut-off of PLOS as a proxy for operation-related adverse outcomes was found using receiver operating characteristic curves. Multivariate logistic regression was conducted on a derivation subcohort to derive a preoperative model predicting PLOS. Receiver operating characteristic curves were performed to validate the model. Patients were stratified by the risk tool and the risks of PLOS were determined. RESULTS: A LOS of ≥3 days following elective LC demonstrated the best diagnostic ability for operation-related adverse outcomes [area under curve (AUC)=0.87] and defined the PLOS cut-off. The rate of PLOS was 6.6% (144/2166), 86.1% of which had a perioperative adverse outcome. PLOS was strongly associated with all adverse outcomes (subtotal, conversion-to-open, intraoperative complications, postoperative complication/imaging/intervention) ( P <0.001). The preoperative model demonstrated good diagnostic ability for PLOS in the derivation (AUC=0.81) and validation cohorts (AUC=0.80) and stratified patients appropriately. CONCLUSIONS: Morbidity in PLOS patients is significant and pragmatic patient selection in accordance with the risk tool may help centers improve resource utilization, risk stratification, and their consent process. The risk tool may help select candidates for cholecystectomy in a strictly ambulatory/outpatient center.

Index Admission Cholecystectomy for Biliary Colic Precludes the Risk of Readmissions with Biliary Complications and should be Standard Treatment.

BACKGROUND: Emergency biliary colic admissions can be managed with an index or elective laparoscopic cholecystectomy (LC). Opting to perform an elective LC may have significant repercussions such as the risk of readmissions before operation with further attacks or with biliary complications (e.g. cholecystitis, pancreatitis, choledocholithiasis). The risk of readmission and biliary complications in patients admitted with biliary colic but scheduled for elective surgery has never been investigated. The secondary aim was to compare rates of peri-operative morbidity between the index admission, elective and readmission LC cohorts. METHOD: All patients admitted with a diagnosis of biliary colic over a 5-year period and proceeding to LC were included in the study (n = 441). The risk of being readmitted and suffering further morbidity whilst awaiting elective LC was investigated. Peri-operative morbidity was compared between the index admission, elective and readmitted LC groups using univariate and multivariate analysis. RESULTS: Following a biliary colic admission, the risk of readmission whilst awaiting elective LC is significant (2 months-25%; 10 months-48%). In this group, the risks of subsequent biliary complications (18.0%) and the requirement for ERCP (6.5%) were significant. Patients who are readmitted before LC, suffer a more complicated peri-operative course (longer total length of stay, higher post-operative complications, imaging and readmission). DISCUSSION: Index admission LC for biliary colic avoids the significant risk of readmission and biliary complications before surgery and should be the gold standard. Readmitted patients are likely to have higher rates of peri-operative adverse outcomes. Patients should be counselled about these risks.

Laparoscopic Lumen-guided cholecystectomy in face of the difficult gallbladder.

BACKGROUND: Where the critical view of safety cannot be established during cholecystectomy, certain salvage techniques are indicated to reduce the likelihood of bile duct injury. The present study describes a salvage technique termed the "laparoscopic lumen-guided cholecystectomy" (LLC) and reports its peri-operative outcomes. METHOD: A summary of the technique is as follows: (1) Hartmann's pouch is incised and stones are evacuated; (2) the cystic anatomy is inspected from the inside of the gallbladder; (3) the lumen is used to guide retrograde dissection towards the cystic pedicle; (4) cystic duct control is achieved if deemed safe. LLC cases performed between June 2020 and January 2022 in a single health board were included. The operative details and peri-operative outcomes of the technique are reported and compared to cases of similar difficulty where the LLC was not attempted. RESULTS: LLC was performed in 4.6% (27/587) of cases. In all 27 cases, LLC was performed for a "frozen" cholecystohepatic triangle. Hartmann's pouch was completely excised in all cases (27/27) and cystic duct control was achieved in 85.2% of cases (23/27). No cases of bile leak or ductal injury were reported. Rates of bile leak, post-operative complications and ERCP were lower following LLC compared to the group where LLC was not attempted (p < 0.01). CONCLUSION: LLC is a safe salvage technique and should be considered in cases where the critical view of safety cannot be established. The technique achieves cystic duct control in the majority of cases and favourable outcomes in the face of a difficult cholecystectomy.

The impact on complication rates of delayed routine pessary reviews during the COVID-19 pandemic.

INTRODUCTION AND HYPOTHESIS: During the COVID-19 pandemic, guidance was issued in the United Kingdom advising a delay in routine pessary reviews. The impact of this has not been fully explored. The null hypothesis for this study is that delayed routine pessary reviews during the COVID-19 pandemic did not result in a statistically significant increase in complication rate. METHODS: A retrospective comparative cohort study was conducted in NHS Tayside, Scotland, involving 150 patients pre-pandemic and 150 patients during the COVID-19 pandemic (before exclusions). Their notes were reviewed identifying age, care provider, pessary type, length of pessary usage, review date, time elapsed since the previous review, bleeding/infection/ulceration, removal issues, pessary replacement and outcome. Patients excluded were those with no pessary in situ at review, reviews at ≤4 months and >8 months (pre-pandemic) and reviews at ≤8 months (COVID-19 pandemic). RESULTS: The pre-pandemic group (n=106) had average review times of 10.1,6.2 and 6.2 months for cubes, rings and all others. Overall rates of bleeding/infection/ulceration; reported removal issues; and pessary subsequently not replaced were 9.4%, 11.3% and 5.7% respectively. The COVID-19 pandemic group (n=125) had average review times of 14.7, 10.8 and 11.4 months for cubes, rings and all others. Overall rates of bleeding/infection/ulceration; reported removal issues; and pessary subsequently not replaced were 21.6%, 16.0%, and 12.0% respectively. CONCLUSIONS: Overall, there was a significant increase in rates of bleeding/ulceration/infection (p=0.01). When individual pessaries were considered, this only remained true for rings (p=0.02). Our data would suggest that routine ring pessary reviews should not be extended beyond 6 months or risk bleeding/ulceration/infection.