Low Leak Research Articles

Numerical simulation and risk assessment of toluene tank leakage in petrochemical industries, China.

Large-capacity toluene storage tank leakage accidents can lead to severe casualties and environmental damage. In this study, numerical simulation of the toluene leakage accidents is performed using PHAST and ALOHA softwares across 16 scenarios. The present research focuses on the dispersion of toluene lethal and toxicity clouds, as well as the associated risks from vapor cloud explosions and pool fires resulting from the large-capacity toluene storage tank leakage. Meanwhile, the effects of influential factors such as leakage height, wind speed, ambient temperature, and atmospheric stability on toluene leakage accidents are also discussed, and then the worst-case scenario of the toluene leakage accident is obtained. The effects of wind speed, ambient temperature, leakage height, and atmospheric stability on outcomes such as toxic clouds, vapor dispersion, explosions, and pool fires are also analyzed. The result reveals that toxic cloud dispersion increases with ambient temperature, while the impact of vapor cloud explosions and pool fires decreases with the increase of leak heights. Wind speed significantly affects pool fire spread. The influential factors related to maximizing hazard range including low leak heights, low wind speeds, high temperatures, and stable conditions are obtained. Risk analysis indicates that vapor cloud explosions significantly impact outdoor potential loss of life (PLLoutdoor) compared with other incidents. Scenario 4 within a directional range from 33.8 to 56.3° shows the highest incident frequencies, highlighting its importance for risk monitoring. These findings are crucial for enhancing emergency response strategies and safety protocols in industrial safety management.

647. INDOCYANINE GREEN (ICG) IDENTIFICATION OF A CISTERNA CHYLI LEAK FOLLOWING RADICAL OESOPHAGO-GASTRECTOMY WITH 2-FIELD LYMPHADENECTOMY: DESCRIPTION OF A NEW TECHNIQUE

Abstract Background Chyle leak is a rare but feared complication post oesophago-gastrectomy, with far-reaching clinical and resource impacts including infection, re-admission and prolonged hospital stay, invasive procedures, and potentially missing the adjuvant therapy window. Low volume leaks can be managed medically via low-fat diet, nutritional support, and somatostatin analogues. Those of higher volume, or where medical management has failed, require radiological or surgical techniques. Where described, these techniques address leaks from a thoracic duct source and are therefore not applicable in patients having undergone oesophago-gastrectomy with radical two- or three- field lymphadenectomy, or where the suspected leak source is from abdominal lymphatics. Methods We report the case of a 78-year-old male diagnosed with cT4a N1 M0 oesophageal adenocarcinoma of the gastro-oesophageal junction. Following neoadjuvant chemotherapy, he underwent robotic-assisted two-phase oesophago-gastrectomy with two-field lymphadenectomy, in which the thoracic duct was identified and ligated. He returned one week post discharge with a left chylothorax. Drinage and medical management were unsuccessful, as were two radiological and one laparoscopic attempt at embolization of the leak. We describe a novel technique utilising indocyanine green (ICG) to identify and facilitate control of a cisterna chyli leak post-oesophago-gastrectomy with radical lymphadenectomy. Results Laparoscopy was performed and indocyanine green injected into the proximal jejunum submucosa, draining via mesenteric lymphatics to the cisterna chyli. Subsequent thoracoscopy revealed a prominent lymphatic channel around the left crus which was ligated. However, further leak was seen through the hiatus upon administration of high-fat jejunostomy feed. Re-laparoscopy revealed a leak from the cisterna chyli which was successfully ligated with ethibond sutures, leading to cessation of chyle leak and successful discharge of the patient, who subsequently received adjuvant therapy within the treatment window. Conclusion We describe a safe and effective novel technique for management of chyle leak from abdominal lymphatics or the cisterna chyli following oesophago-gastrectomy with radical two-field lymphadenectomy. https://drive.google.com/file/d/1nCNnowdJVPlV0GOleXVNVMshuU19kCb/view?usp=sharing

Anastomotic leak rate following the implementation of a powered circular stapler in elective colorectal surgeries: a retrospective cohort study.

The objective of this study was to compare the anastomotic leak rates between powered and manual circular staplers in elective left-sided colorectal resections. A retrospective cohort study of elective left-sided colorectal resections before and after implementation of a powered circular stapler at a tertiary care center was conducted. The manual stapler group consisted of consecutive resections performed between January 2016 to December 2016 and the powered stapler group, between September 2021 and December 2022. Primary outcome was 30-day anastomotic leak rate. A chi-squared analysis was performed to compare anastomotic leak rates. Factors associated with anastomotic leak were examined. Two-hundred forty-seven patients were included: 154 in the manual stapler group and 93 in the powered stapler group. Mean (SD) age was 60 (15) years old, 37.7% were female and 72.9% of resections were performed for malignancy. Both groups had similar patient characteristics and surgical technique. Overall leak rate was 2.0% in the manual stapler group and 10.8% in the powered stapler group. The powered staplers were found to have 6.06 times the odds of leak compared to manual staplers (95% CI, 1.62-22.65; p = 0.01). None of the other factors were found to be associated with anastomotic leak. Patients who had left-sided colorectal anastomosis had higher anastomotic leak rates with powered compared to manual circular staplers. This finding is contrary to previous retrospective studies that found lower leak rates with powered staplers.

Safety of robotic cholecystectomy as index training procedure: the UK experience.

To evaluate the safety profile of robotic cholecystectomy performed within the United Kingdom (UK) Robotic Hepatopancreatobiliary (HPB) training programme. A retrospective evaluation of prospectively collected data from eleven centres participating in the UK Robotic HPB training programme was conducted. All adult patients undergoing robotic cholecystectomy for symptomatic gallstone disease or gallbladder polyp were considered. Bile duct injury, conversion to open procedure, conversion to subtotal cholecystectomy, length of hospital stay, 30-day re-admission, and post-operative complications were the evaluated outcome parameters. A total of 600 patients were included. The median age was 53 (IQR 65-41) years and the majority (72.7%; 436/600) were female. The main indications for robotic cholecystectomy were biliary colic (55.5%, 333/600), cholecystitis (18.8%, 113/600), gallbladder polyps (7.7%, 46/600), and pancreatitis (6.2%, 37/600). The median length of stay was 0 (IQR 0-1) days. Of the included patients, 88.5% (531/600) were discharged on the day of procedure with 30-day re-admission rate of 5.5% (33/600). There were no bile duct injuries and the rate of conversion to open was 0.8% (5/600) with subtotal cholecystectomy rate of 0.8% (5/600). The current study confirms that robotic cholecystectomy can be safely implemented to routine practice with a low risk of bile duct injury, low bile leak rate, low conversion to open surgery, and low need for subtotal cholecystectomy.

Multigenerational exposure to temperature influences mitochondrial oxygen fluxes in the Medaka fish (Oryzias latipes).

Thermal sensitivity of cellular metabolism is crucial for animal physiology and survival under climate change. Despite recent efforts, effects of multigenerational exposure to temperature on the metabolic functioning remain poorly understood. We aimed at determining whether multigenerational exposure to temperature modulate the mitochondrial respiratory response of Medaka fish. We conducted a multigenerational exposure with Medaka fish reared multiple generations at 20 and 30°C (COLD and WARM fish, respectively). We then measured the oxygen consumption of tail muscle at two assay temperatures (20 and 30°C). Mitochondrial function was determined as the respiration supporting ATP synthesis (OXPHOS) and the respiration required to offset proton leak (LEAK(Omy)) in a full factorial design (COLD-20°C; COLD-30°C; WARM-20°C; WARM-30°C). We found that higher OXPHOS and LEAK fluxes at 30°C compared to 20°C assay temperature. At each assay temperature, WARM fish had lower tissue oxygen fluxes than COLD fish. Interestingly, we did not find significant differences in respiratory flux when mitochondria were assessed at the rearing temperature of the fish (i.e., COLD-20°C vs. WARM -30°C). The lower OXPHOS and LEAK capacities in warm fish are likely the result of the multigenerational exposure to warm temperature. This is consistent with a modulatory response of mitochondrial capacity to compensate for potential detrimental effects of warming on metabolism. Finally, the absence of significant differences in respiratory fluxes between COLD-20°C and WARM-30°C fish likely reflects an optimal respiration flux when organisms adapt to their thermal conditions.

Magnetically assembled flexible phase change composites with vertically aligned structures for thermal management and electromagnetic interference shielding

Phase change material (PCM) is promising in achieving zero-energy thermal management because of its prominent thermal storage capacity and steady phase-change temperature. However, low intrinsic thermal conductivity (TC), liquid leak, and solid rigidity are long-standing bottlenecks for heat-related applications. Here, we report an innovative dual-encapsulation strategy to develop multifunctional phase change composite (FMP) with vertically aligned NdFeB@Ag arrays and styrene-ethylene-propylene-styrene (SEPS) crosslinked network in paraffin (PA). The NdFeB@Ag arrays induced by magnetic-field driven procedure can offer the consecutive/oriented highways for efficient heat-transfer, and an electric/magnetic heterostructure for electromagnetic interference shielding efficiency (EMI SE). The flexible SEPS block copolymer not only ensures the high flexibility of PCM, but also combines with oriented NdFeB@Ag arrays for dual encapsulating PA. This multifunctional FMP can achieve high TC of 2.59 W m−1 K−1, attractive EMI SE of 35.42 dB, prominent enthalpy density of 120 J g−1, and impressive Joule heating performance, together with leakage-proof, dynamic assembly, and salient charging/discharging durability. Furthermore, the FMP-supported device is demonstrated for thermal energy harvesting and utilization. This dual-encapsulation design opens a new avenue for exploiting multifunctional PCMs for thermal management, anti-EM radiation, and low-grade exhaust heat utilization.

Development of Company-Specific Emission Factors with Confidence Intervals for Natural Gas Customer Meters in Southern California.

Methane is both a significant and short-lived greenhouse gas compared to CO2, and reducing methane emissions from natural gas distribution systems may offer cost-effective reduction opportunities. We report substantial new direct leak rate measurements from customer meter set assemblies (MSAs) in Southern California. In a novel way, emission factors are defined in terms of aboveground Hazardous and Nonhazardous leak categories, which take direct advantage of readily available industry leak data. We also studied leaks that were not detected as part of normal leak survey procedures. As a result, this yields company-specific emission factors that can be used to track progress in reducing methane emissions. This approach also has the advantage of explicitly accounting for the skewed or fat-tail distribution of leak rates by treating high flow rate MSA leaks separately from low flow rate MSA leaks. The Southern California Gas (SoCalGas) methane emission factors, based on 485 leak rate measurements by direct enclosure, were 4.55 (95% confidence interval: 2.32 to 7.14) kg/day for Hazardous leaks, 0.149 (0.119 to 0.183) kg/day for Nonhazardous leaks, and 0.0039 (0.0003 to 0.0198) kg/day for Non-Detected leaks. The percentage of surveyed meters with nondetected leaks was 29.1% (24.3 to 34.6%). Based on a robust Monte Carlo analysis, total leak emissions from MSAs for the SoCalGas system were reduced by 35% based on data from 2015 to 2022. These reductions were attributed to surveying a larger number of MSAs and accelerated leak repair rates. In traditional population-based emission inventories, an individual emission factor for a given asset category is multiplied by the total population of MSAs within the category. This approach simply cannot capture the reduction in leak numbers and methane emissions resulting from leak mitigation and prevention programs.

Optimization of the mass ratio of siloxane crosslinkers for poly(2,6-dimethyl-1,4-phenylene oxide) anion exchange membranes to improve acid enrichment by electrodialysis

Proton blocking anion exchange membranes (AEMs), which are employed in electrodialysis technology, show promise in acid recovery from industrial waste. A series of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) membranes were prepared using (3-aminopropyl)trimethoxysilane (APTMS) and weakly functionalized bases including N-butylimidazole (N-BuIm). Were networked to create AEMs with low leak rates. It was discovered that the appropriate concentration of siloxane crosslinker raised the membrane matrix's density and lowered the AEM matrix's hydrophilicity. Thermogravimetric measurements and water absorption have confirmed this, and the membranes in this series even swell up to 8.61 %. The maximum H+ concentration concentrated by the cross-linked AEM (BPPO/5Si) during the ED with a current density of 10 mA∙cm−2 was 2.35 M, which was higher than the concentration concentrated by the uncross-linked AEM (BPPO/OSi), which was 1.90 M (beginning concentration: 1.00 M). The current efficiency was 44.8 % and the energy consumption was only 1.81 kW ∙h∙kg−1. A balance between proton blocking and SO42− ions transport was achieved by the optimized AEM, which exhibited increased hydrophobicity and smaller ion clusters. The improved AEM was found to have fewer ionic clusters and greater hydrophobicity. For cross-linked AEMs, a trade-off between SO42− ions transport and proton blocking was thus accomplished. This work is thought to offer direction for developing sophisticated proton blocking AEMs.

Comparing two-year outcomes of balloon-expandable Myval and self-expanding Evolut R in severe aortic valve stenosis

BackgroundThe new balloon-expandable (BE) Myval transcatheter heart valves (THV) has shown promising early results with low paravalvular leak (PVL) and permanent pacemaker implantation (PPI) rates. Limited data are available regarding its long-term performance. We aimed to compare the 2-year clinical and echocardiographic outcomes of transcatheter aortic valve replacement (TAVR) using the self-expanding (SE) Evolut R and the BE Myval THVs. MethodsThe EVAL study included 166 patients with severe aortic valve stenosis who underwent TAVR either with SE Evolut R (n = 108) or BE Myval (n = 58) THV. Primary objectives include comparison on clinical efficacy (freedom from all-cause mortality, stroke, and cardiovascular hospitalization), echocardiographic performance and PPI rates between the two THVs. ResultsAt 2-year the BE Myval group showed higher clinical efficacy (86% vs. 66%,HR:2.62, 95%CI 2.2–5.1;p = 0.006), with fewer cardiac hospitalizations (3.4% vs. 13.9%,p = 0.03). No significant differences in all-cause mortality, cardiovascular mortality, or stroke rates were observed. The proportion of patients with ≥moderate PVL was significantly lower in the BE Myval compared to the SE Evolut R group (4%vs. 22%,p = 0.008). The mean transvalvular gradient was significantly higher in the SE group compared to the BE group (9.5 ± 4.3 vs. 6.9 ± 2.2 mmHg,p < 0.001), however there was no difference in the percentage of patients with a mean gradient ≥20 mmHg between the two groups. ConclusionsBoth THVs offer similar 2-year clinical outcomes. The BE Myval THV demonstrated advantages with higher clinical efficacy and lower PVL incidence. Longer follow-up and randomized trials are needed to validate these results and assess Myval's sustained performance and durability.

The Role of the Supine Empty Stress Test in the Evaluation of Women with Stress Urinary Incontinence: A Retrospective Cohort Study.

The International Continence Society recommends the supine empty stress test (SEST) as an accessory test in the evaluation of women with urinary incontinence, especially for the presence of intrinsic sphincter deficiency (ISD). The aim of this study was to investigate the relationship between the SEST and clinical findings in women diagnosed with stress urinary incontinence with single voiding cycle ambulatory urodynamics (AUM). AUM tracings of patients with lower urinary tract symptoms (LUTS = Lower urinary tract symptoms) (n = 513) were retrospectively reviewed, and 364 charts with urodynamic SUI were analyzed. Demographics, examination findings, scores of the Sandvik Incontinence Severity Index and validated questionnaires, and AUM findings were compared between SEST-positive and -negative groups. Additionally, the diagnostic accuracy of the SEST in the diagnosis of low abdominal leak point pressure (ALPP ≤ 60 cm H2O) in women with pure urodynamic SUI was calculated. The SEST was positive in 41.8% (n = 152) of the cohort. Women with a positive SEST had higher scores on the Sandvik severity index (9.2 ± 3.6 vs. 7.5 ± 3.8, p = 0.003) and lower ALPP (79.6 ± 29.3 vs. 98.4 ± 31.3, p < 0.001). The negative predictive value of the SEST for ISD was found to be 92.4%. Thus, the SEST seems to be an objective clinical test reflecting urinary incontinence severity while excluding the presence of ISD.

EGS P11 Super-charged colonic interposition after Upper Gastrointestinal tract resections: technical considerations from both benign and malignant cases and review of literature

Abstract Background Oesophageal reconstruction is performed after an oesophagectomy, for either malignant or benign pathology. During reconstruction, variables include choice of conduit, route of reconstruction, and site of anastomosis. The stomach is preferred for neo-oesophageal reconstruction. However, when the stomach is not viable, alternatives including colon, jejunum, skin, or anterolateral thigh (ALT) musculocutaneous flaps are considered. Of these, colon is preferred for its ability to provide long-length grafts and reliable vascular supply. However, complications remain significant problems, including ischaemia at the anastomosis. To address this, 'supercharging’ and ‘super drainage' techniques are used to enhance arterial flow and venous drainage via microvascular anastomosis. Methods Case 1 involves a 61-year-old male who underwent an oesophagectomy for GOJ adenocarcinoma. A year later he developed a strangulated diaphragmatic hernia with an ischaemic gastric conduit, which was replaced with an isoperistaltic colonic interposition using transverse and left colon with super-drainage. 3 years later, the patient presented with pancreatitis, perforated gallbladder, and duodenum. Diffuse ischaemic changes of the interposed colon were recognised. A re-do colonic interposition using right colon with an arterial graft between the right transverse cervical artery and branch of ileal artery and super-drainage via a branch of the ileal and right external jugular veins was created. Results Case 2 involves a 68-year-old female who underwent an elective hiatus hernia repair with Nissen’s fundoplication. She deteriorated shortly post-operatively where re-look surgery found early hernia recurrence causing strangulation of the distal oesophagus and proximal stomach leading to ischaemia, necrosis, and perforation. She underwent a laparotomy and resection of the ischaemic distal oesophagus and proximal stomach, oesophagostomy and feeding jejunostomy. 16 months later, she underwent interposition of the right colon between the proximal oesophagus and remaining stomach. Arterial flow was adequate and supercharging was performed between the left external jugular vein and a branch of the middle colic vein. Conclusions There is limited literature on methods of both supercharging and super-drainage, as well as the optimal choice of organ for neo-oesophageal reconstruction. Currently, no established treatment protocols exist. There is evidence that supercharging and super-drainage are associated with longer operative times. However, benefits include lower leak incidence, shorter duration to oral intake, and reduced length of stay in relation to interposition without supercharge. Associated venous congestion may contribute to anastomotic leak, and may be prevented by super-drainage. Whilst supercharging has been reported worldwide, our case series adds to the UK practice showing it improves patient outcomes in an NHS setting.

Quantifying non-steady state natural gas leakage from the pipelines using an innovative sensor network and model for subsurface emissions - InSENSE

Detecting and quantifying subsurface leaks remains a challenge due to the complex nature and extent of belowground leak scenarios. To address these scenarios, monitoring and evaluating changes in gas leakage behavior over space and time are crucial for ensuring safe and efficient responses to known or potential gas leaks. This study demonstrates the capability of linking environmental and gas concentration data obtained using a low-cost, near real-time methane (CH4) detector network and an inverse gas migration model to capture and quantify non-steady state belowground natural gas (NG) leaks. The Estimating Surface Concentration Above Pipeline Emission (ESCAPE) model was modified to incorporate the impact of soil properties on gas migration. Field-scale controlled NG experiments with leakage rates ranging from 37 to 121 g/h indicate that elevated belowground near-surface (BNS) gas concentrations persist long before elevated surface concentrations are observed. On average, BNS CH4 concentrations were 20%–486% higher than surface CH4 concentrations within the monitoring radius of 4 m from the leak location. An increase in the BNS CH4 concentration was observed within 3 h as the leak rate increased from 37 to 89 g/h. However, due to the atmospheric fluctuations, any changes in surface CH4 concentrations could not be confirmed within this period. The plume area of the BNS CH4 extended approximately two times farther than that of the surface CH4 as the gas leak rate increased from 37 to 121 g/h. The estimated NG leak rates by the modified ESCAPE model agreed well with the experimental NG leak rates (m = 0.99 and R2 = 0.77), demonstrating that including soil characteristics and BNS CH4 measurements can advance estimations of non-steady NG leak rates in low and moderate NG leak rate scenarios. The CH4 detector network and model show potential as an innovative tool to improve operators' risk assessment and NG leakage response.

Study on Breakage Characteristics and Anti-Breakage Theory for Pressure-Relieved CBM Drainage by Surface Wells in Coalbed Groups Covered by Super-Thick Pedosphere

During the mining of highly gassy and low-permeability coalbed groups, massive pressure-relieved desorbed coal bed methane (CBM) is stored in the fracture zone and in the gob under the impact of mining activities. Surface wells can cross the fracture zone and the gob to drain a large amount of highly concentrated pressure-relieved CBM. CBM drainage by surface wells is an effective technology for disaster control. However, it is difficult to drill or maintain surface wells in the mining disturbance zone and overlying strata in the gob. The keyisto prevent the surface wells in the mining disturbance zone from being broken and to keep the whole surface wells unblocked. This study adopted a variety of research methods, including similar-material simulation in laboratory, numerical simulation, onsite monitoring and industrial tests. Specifically, the strata structure of surface wells for pressure-relieved CBM drainage was explored, and the characteristics of roof strata movement and stress redistribution under coalbed group mining were analyzed. Besides, positions where the surface wells are prone to breakage were found. Furthermore, based on the mechanical analysis and breakage characteristics of surface wells, the anti-breakage principle of “resistance and dodge” and the surface well completion and protection method of “upper stop and lower leak” were proposed. The proposed theory and method were then applied to pressure-relieved CBM drainage surface wells in a coalbed group covered by the super-thick pedosphere in the Huainan Coal Field. The application results indicate that the proposed theory and method succeeded in solving the breakage of surface wells and realizing the smooth transport of CBM product. The surface wells can completely resist the mining disturbance, achieving an average single-well pure CBM production of 2.71 million m3, an average service period of 482 d, and a maximum pure CBM production of 4.32 million m3.

Comparison of ventilation techniques for compensation of mask leakage using a ventilator and a regular full-face mask: A bench study

BackgroundThe use of noninvasive ventilation (NIV) during and after extubation is common. We designed this study to determine the optimal strategy to compensate for mask leaks and achieve effective ventilation during NIV by comparing commonly used operating room ventilator systems and a regular facemask. MethodsWe tested four operating room ventilator systems (Dägger Zeus, Dägger Apollo, Dägger Fabius Tiro, and General Electric Healthcare Carestation 650) on a lung model with normal compliance and airway resistance and evaluated pressure control ventilation (PCV), volume control ventilation (VCV), and AutoFlow mode (VAF). We set the O2 flow at 10 L/min and the maximal flow at 13, 16, or 26 L/min. We simulated five leak levels, from no leak to over 40 L/min (I to V levels), using customized T-pieces placed between the lung model and the breathing circuit. We recorded the expired tidal volume (Vte) from the lung model and peak inspiratory pressure via two flow/pressure sensors that were placed distally and proximally to the T-pieces. Results1. Comparison of four ventilators: with any given ventilation mode, an increase in leak level caused a decrease in Vte. With PCV, only Zeus produced Vte larger than 150 ml at leak level V. 2. Effect of ventilation mode on Vte: across all four ventilators, PCV resulted in a higher Vte than VCV and VAF (P < 0.01). PCV mode with all ventilators at leak level II provided Vte values that were equal to or greater than those obtained with no leak. 3. Effect of O2 flow on Vte Using PCV mode: only Carestation 650 Vte at leak level II during PCV were significantly greater with 16 L/min O2 flow compared with 10 L/min O2 flow (P < 0.01). 4. Actual leak: increasing the O2 flow from 10 L/min to the maximum O2 flow dramatically increased the real leak with all 4 ventilators at any fixed leak level (P < 0.01). 5. Preset PIP vs. actual PIP with PCV: at low preset PIP and leak levels such as leak II and III, the discrepancy between preset PIP and actual PIP was small. The disparity between the preset and actual PIP grew when the target PIP and the leak level were raised. ConclusionFor NIV using a mask, the ventilator is preferred whose Pressure generator is Turbine, the PCV mode is preferred in the ventilation mode and the oxygen flow is set to 10 L/min or maximum oxygen flow.

398. THE HYBRID INTRA-THORACIC OESOPHAGO-GASTRIC ANASTOMOSIS—CONTEMPORARY PERFORMANCE WITH LOW BENIGN ANASTOMOTIC STRICTURE FORMATION

Abstract Background The intra-thoracic linear stapled semi-mechanical anastomosis is associated with reduced rates of benign anastomotic stricture when compared with circular stapled and end-to-end hand-sewn methods. The hybrid anastomosis is a modification of this. The hand-sewn posterior wall, extended with a stapler firing provides the theoretical advantage of increased luminal patency. It has been published as a single surgeon experience from our institutions (1993–2011), with low leak rate and stricture rate of ten percent. These patients largely underwent upfront surgery. Methods We assessed the performance of this hybrid anastomotic technique amongst multiple surgeons, in a contemporary setting with high use of neoadjuvant therapy, compared with the end-to-end hand-sewn anastomosis. Patients undergoing open Ivor Lewis oesophagectomy over a 6 year period were identified using the prospective oesophagectomy database across two public hospitals. Chart review was used to compile data on anastomotic technique, reflux symptoms, PPI use and endoscopic dilatations. Results There were 80 patients, with minimum 12 month and mean 24 months follow up. 60 patients underwent hybrid anastomosis and 20 hand-sewn. Four surgeons oversaw more than 10 anastomoses. 70% of patients received neoadjuvant treatment. Four anastomotic leaks required intervention (5%). Benign stricture formation requiring endoscopic dilatation was more common in the hand-sewn group (35%) compared with the hybrid group (12%) (p = 0.0061). All strictures were identified within 12 months. On multi-variate analysis, anastomotic leak, neoadjuvant therapy, smoking, diabetes and vascular comorbidities did not predict stricture formation. Symptomatic reflux approached 50% in both groups, despite 89% long term PPI adherence. Conclusion We demonstrate that the hybrid anastomosis continues to achieve low rates of benign anastomotic stricture amongst multiple surgeons, even in the era of neoadjuvant therapy. Symptomatic reflux remains common after oesophagectomy, so PPI should be used long-term. Outcomes for both anastomoses compare to published standards. These results are relevant to consider when modifying techniques for minimally invasive anastomosis.

Baska mask vs ProSeal Laryngeal mask on airway seal pressure in cases undergoing general anesthesia by mechanical ventilation: A randomized controlled trial

ABSTRACT Background Supraglottic Airway Devices (SGAs) are designed to counteract the drawbacks of endotracheal intubation. They have proven to be easy to use, robust, versatile, and usable in many difficult situations. This work aims to investigate the use of the Baska Mask (BM) airway and ProSeal™ Laryngeal Mask Airway (PLMA) as SGAs for ventilation. Methods This randomized controlled trial was carried out on 74 cases aged 21–65 years old for elective surgery of a planned duration of up to 2 h during general anaesthesia with intermittent positive pressure ventilation. Cases were divided into two equal groups. Ventilation was done either by BM® Airway (group BM) or PLMA (group PLMA). Results BM had a shorter insertion time and lower leak fraction versus PLMA, while seal pressure elevated significantly with BM versus PLMA (P < 0.001). PLMA had significantly more cases than the BM mask group complaining of a sore throat at 2 h (P = 0.042). Complication after gastric tube insertion was parallel between both groups. Conclusions BM can be used successfully during anesthesia as it displays a shorter insertion time, lower leak fraction, higher seal pressure, and lower incidence of sore throat and gastric tube insertion complications than PLMA.

A practical approach to LDAR effectiveness evaluation

As a growing number of oil and gas facilities worldwide implement leak detection and repair (LDAR) plans, the owners and the public are interested in better understanding their effectiveness, i.e. how total facility leak emission is decreased as a result of LDAR implementation. For this objective, it is critically important when calculating total mass leak emission to consider an estimated leak lifetime for the leakers found. Obviously, more frequent monitoring and shorter leak repair time should return lower leak lifetime and less emission. This simple yet important factor is mentioned but not detailed in existing guides. Some guides suggest formulae with the same equipment operating time both for leakers and non-leakers, which is not quite accurate since the actual leak lifetime could be significantly less than the total equipment operating time due to the proper LDAR implementation. In this article, we address this gap. The LDAR effectiveness evaluation approach utilizing leak lifetime is suggested and illustrated using examples.

The first clinical data of the SAPIEN 3 aortic valve in the treatment of aortic stenosis in China.

Data on outcomes following transcatheter aortic valve replacement with SAPIEN 3 in China is limited as it was approved by the National Medical Products since 2020. The present study was designed to collect clinical data on the SAPIEN 3 aortic valve in Chinese patients with bicuspid aortic valve and tricuspid aortic valve stenosis. We analyzed the patient characteristics, procedural features and procedural outcomes of the first 438 patients (223 for bicuspid aortic valve and 215 tricuspid aortic valve) from 21 provinces in 74 sites treated with the SAPIEN 3 valve system for transcatheter aortic valve replacement between September 2020 and May 2022. Procedural mortality was 0.7%. 5 cases during the operation were converted to surgery. Among 438 cases, permanent pacemaker implantation was performed in a total of 12 cases (2.7%). The patient had severe leaflet calcification of the aortic valve, with moderate and severe calcification reaching 39.7% and 35.2% respectively. The size of the implanted valves was predominantly 26 mm and 23 mm, reaching 42.5% and 39.5% respectively. The incidence of moderate or severe perivalvular leak in the postoperative period was 0.5%, with a predominance of 90/10 and 80/20 valve deployment height. There was a significant difference in the deployment height of the valve between bicuspid aortic valve and tricuspid aortic valve, with the bicuspid aortic valve having a more deployment height of 90/10. Annulus size in bicuspid aortic valve group was significantly larger than tricuspid aortic valve group. Valve sizing for oversized, within size, and undersized were different between bicuspid aortic valve and tricuspid aortic valve. Procedural success rates were high, with similar and good results for bicuspid aortic valve and tricuspid aortic valve, low perivalvular leak for both valve types, and low permanent pacemaker implantation rates for both valve types. Annulus size, valve sizing and coronary artery height were significantly different in the BAV and TAV group.

Home NIV treatment quality in patients with chronic respiratory failure having participated to the French nationwide telemonitoring experimental program (The TELVENT study)

BackgroundThe ETAPES program is a national telemedicine experiment conducted in France between 2018 and 2023 to investigate whether home non-invasive ventilation (NIV) telemonitoring improves healthcare pathways in patients with chronic respiratory failure (CRF) and impacts healthcare organization. The program provides a combination of therapeutic education and NIV telemonitoring with data processed by an algorithm generating alerts. The TELVENT study objective was to analyze the evolution of ventilation quality in patients included in the ETAPES program. MethodsMulticentric cohort study on patients undergoing long-term NIV included in the ETAPES program between September 2018 and December 2020 and who did not refuse the use of their data for this research. Data were obtained from homecare provider databases. The primary endpoint was to attain successful NIV treatment, which was determined by a combination of daily NIV usage for > 4 h per day, low leaks, and a low apnea-hypopnea index (AHI) identified by the NIV device. Respiratory disability was assessed using the DIRECT questionnaire. Results329 patients were included in the study of which 145 had COPD and 83 had started NIV and ETAPES within one-month delay. Approximately 25% of patients did not achieve the criteria for successful NIV at ETAPES entry. The proportion of patients with successful NIV treatment increased to 86.8% at six months (p = 0.003, Cochran-Armitage trend test) regardless of NIV history and continued to increase at 12 months in newly equipped NIV patients (93.8%, at month 12, p = 0.0026 for trend test). Over time, a significant increase in NIV use and compliance was observed, while AHI significantly decreased in the overall population. No significant decrease was observed for non-intentional leaks. Approximately 4.9 alerts were generated per patient per 6 months. Their number and type (low NIV use, high AHI or leaks) differed among patients based on their NIV history. Respiratory disability score decreased over time compared with baseline. ConclusionThe TELVENT study highlights the importance of remote NIV monitoring to rapidly identify patients with unsuccessful ventilation. The combination of remote monitoring and therapeutic education may improve the quality of home NIV, especially in the first months of treatment.

Endoscopic management of low output recurrent colonic fistula or leak after anterior resection for rectal cancer: a randomized controlled trial

BackgroundColonic anastomotic leak and fistula following anterior resection surgery for rectal cancer are associated with high mortality rates. The incidence of occurrence varies from 2 to 25% and it is difficult to accurately calculate the incidence of fistula and leak post anterior resection, as most of them are asymptomatic. Endoscopic management of fistula and leak has become the first line of management after conservative management in many gastrointestinal surgical centers with the advantages of being less invasive, shorter length of post-operative hospital stay, effective and rapid recovery in comparison to revision surgery. Effective endoscopic management for colonic fistula or leak depends on the clinical status of the patient and fistula characters (time-to-occur and size and site of defect), and device availability.MethodsThis prospective randomized controlled clinical trial included all patients who developed the manifestations of low output recurrent colonic fistula or leak after colonic anterior resection for rectal cancer at Zagazig University Hospital between (December 2020 and August 2022). Sample size was 78 patients divided into two equal groups. Endoscopic group (EG): included 39 patients who underwent endoscopic management. Surgical group (SG): included 39 patients who underwent surgical management.ResultsThe investigators randomized eligible 78 patients into two groups: 39 patients in SG and 39 patients in EG. The median size of the fistula or leak was nine (range: 7–14) mm in EG, versus ten (range: 7–12) mm in SG. Clipping and Endo-stitch device were used in 24 patients versus 15 patients, respectively, in EG while primary repair with ileostomy, and resection & anastomosis were used in 15 patients versus 24 patients, respectively, in SG. Recurrence, abdominal collection, and mortality were the post procedure’s complications with incidence of occurrence of 10.3, 7.7 and 0%, respectively, in EG versus 20.5, 20.5 and 2.6%, respectively, in SG. Excellent, good, and poor were the parameters for quality of life with incidence of occurrence of 43.6, 54.6 and 0%, respectively, in EG versus 28.2, 33.3 and 38.5%, respectively, in SG. Median hospital stay was one (range: 1–2) day in endoscopic group, and seven (range: 6–8) days in SG.ConclusionEndoscopic intervention may offer a successful modality in managing low output recurrent colonic fistula or leak after anterior resection for rectal cancer that did not respond to conservative measures in stable patients.ClinicalTrials.gov ID: NCT05659446.