bluuebunny/crossref_metadata_2025 huggingface dataset:
Quenching and flow of charm and bottom quarks via semi-leptonic decay of D and B mesons in Pb+Pb collisions at the LHC*
Authors: Li 李 Shu-Qing 树清 , Xing 邢 Wen-Jing 文静 , Cao 曹 Shanshan 杉杉 , Qin 秦 Guang-You 广友
Published: May 2024

Heavy flavor particles provide important probes of the microscopic structure and thermodynamic properties of the quark-gluon plasma (QGP) produced in high-energy nucleus-nucleus collisions. We studied the energy loss and flow of charm and bottom quarks inside the QGP via the nuclear modification factor (

) and elliptic flow coefficient (

) of their decayed leptons in heavy-ion collisions at the LHC. The dynamical evolution of the QGP was performed using the CLVisc (3+1)-dimensional viscous hydrodynamics model; the evolution of heavy quarks inside the QGP was simulated with our improved Langevin model that considers both collisional and radiative energy loss of heavy quarks; the hadronization of heavy quarks was simulated via our hybrid coalescence-fragmentation model; and the semi-leptonic decay of D and B mesons was simulated via PYTHIA. Using the same spatial diffusion coefficient for charm and bottom quarks, we obtained smaller

and larger

of charm decayed leptons than bottom decayed leptons, indicating stronger energy loss of charm quarks than bottom quarks inside the QGP within our current model setup.
Clear Water Scour Depth Prediction using Gradient Boosting Machine and Deep Learning
Authors: Singh Balraj , Minocha Vijay K
Published: May 2024

The scouring process in adjacent to spur dikes has the potential for compromising the stability of riverbanks. Hence, it is necessary for river engineering to conduct precise measurement of maximum scour depth in the vicinity of spur dikes. Nevertheless, the determination of the maximum scour depth has proven to be a challenging task, primarily due to the complex nature of the scour phenomena associated with these structures. In this study, two data-driven models, namely the Gradient Boost Machine (GBM) and Deep Learning (DL), were developed to predict the clear water scour depth near to a spur dike. A total of 154 distinct observations have been collected from previous literatures. A total of 103 observations were utilized for training the model, while 53 observation were allocated for validation purposes. Several performance assessment measures were employed to evaluate the performance of the models, including the correlation coefficient (CC), root-coefficient of determination (R2), scattered plot, variation plot, and box plot. GBM outperformed the DL on the basis of above-mentioned assessment measures. Sensitivity analysis suggests that l/d50 is the most influences input parameter. Thus, the conclusion suggested that both the data-driven model can be used in the prediction of the clear water scour depth around spur dikes but GBM have highest accuracy.
The elastic stiffness tensor of cellulosic viscose fibers measured with Brillouin spectroscopy
Authors: Czibula Caterina , Ulz Manfred H , Wagner Alexander , Elsayad Kareem , Hirn Ulrich , Koski Kristie J
Published: May 2024

Brillouin light scattering spectroscopy is applied to study the micromechanics of cellulosic viscose fibers, one of the commercially most important, man-made biobased fibers. Using an equal angle scattering geometry, we provide a thorough description of the procedure to determine the complete transversely isotropic elastic stiffness tensor. From the stiffness tensor the engineering-relevant material parameters such as Young’s moduli, shear moduli, and Poisson’s ratios in radial and axial fiber direction are evaluated. The investigated fiber type shows that, at ideal conditions, the material exhibits optical waveguide properties resulting in spontaneous Brillouin backscattering which can be used to obtain additional information from the Brillouin spectra, enabling the measurement of two different scattering processes and directions with only one scattering geometry.
Extended finite element method with cell-based smoothing for modeling frictional contact crack-induced acoustic nonlinearity involving distorted mesh
Authors: Li Feilong , Yang Na , Su Yue , Sun Xiaoqiang , Guo Dong
Published: May 2024

This study proposes a 2D cell-based smoothed extended finite element method (CS-XFEM) for accurate and efficient simulation of nonlinear ultrasonic wave propagation in solid structures, specifically addressing the effects of frictional contact in cracks. Traditional mesh discretization methods for cracks often suffer from mesh distortion and computational instability owing to their high aspect ratios. To overcome this, CS-XFEM integrates a cell-based smoothing technique into XFEM to model the frictional contact of a crack. A comprehensive numerical example demonstrates the advantages of CS-XFEM. The results show that CS-XFEM exhibits a higher convergence rate and enables a larger critical time increment than XFEM. Specifically, the critical time increment of CS-XFEM was found to be twice that of XFEM, leading to a 50% reduction in the total computational time. These findings confirm that CS-XFEM is an efficient, accurate, and robust numerical method for studying the acoustic nonlinearity induced by crack-induced frictional contact.
Influence of thermocycling on the functional properties of the NiTi alloy produced by wire arc additive manufacturing
Authors: Bikbaev Rashid , Resnina Natalia , Anand Iyamperumal Palani , Belyaev Sergey , Thangamani Geethapriyan
Published: May 2024

The influence of the thermocycling under a stress of 200 and 300 MPa on the martensitic transformation temperatures, recoverable and irreversible strain was study in the NiTi samples produced by wire arc additive manufacturing (WAAM). Two types of samples were used: the T1 sample including the Ti-rich NiTi and Ni-rich NiTi layers in the working length and the T2 sample including only the Ni-rich NiTi layers. It was found that the variation in the martensitic transformation temperatures on thermal cycling depended on the chemical composition of the layer. The transformation temperatures decreased on thermal cycling in the Ti-rich NiTi layer (in T1 sample), whereas they were constant in the Ni-rich NiTi layers (in T1 and T2 samples). The recoverable strain in both samples did not change during thermal cycling. The irreversible strain was found in the T1 sample regardless of stress acting on thermal cycling, while T2 sample showed the plastic strain only in the first cycle under 300 MPa. It was shown that the difference in a functional behavior of the T1 and T2 samples on thermocycling was due to that the T1 sample contained the Ti-rich NiTi layer, that was characterized by a low dislocation slip limit contrary to the Ni-rich layers which were hardened by the Ni4Ti3 precipitates.
Subway track foundation settlement deformation prediction based on the BiLSTM-AdaBoost model
Authors: Dang Xifeng , Yin Xiao , Liu Jianwei , Wu Jincheng , Wang Xin , Liu Yongqiang , Sun Shoubin
Published: May 2024

The rapid economic expansion has spurred extensive construction near subway networks, impacting the stability of their track foundations. Consequently, it’s crucial to monitor and predict settlement in subway track foundations. However, the dynamic deformation patterns often exhibit nonlinearity and non-stationarity, posing challenges for traditional linear regression models. To tackle this, our study integrates the BiLSTM (bi-directional long short-term memory) network with the AdaBoost ensemble learning algorithm. Using settlement data from Shanghai metro monitoring points, the model is trained and evaluated employing R2 (coefficient of determination), MAE (mean absolute error), and RMSE (root mean square error). Results show that our proposed model displays superior predictive accuracy compared to the LSTM and the BiLSTM, with an average training set R2 of 0.99, test set R2 of 0.78, average MAE of 0.32 mm, and average RMSE of 0.4 mm. Consequently, for forecasting subway track foundation deformations, employing our network model ensures highly accurate predictive capabilities.
Un/published: Presence and Absence in Contemporary Erasure Poetry
Authors: Schaefer Heike
Published: May 2024

Erasure is a popular form of appropriative poetry that refashions found material by partially effacing it. Made of salvaged fragments and deletion marks, erasure poetry puts processes of obliteration on display and provides a structural analogy for both the social erasure of marginalized groups and the critical rewriting of hegemonic discourses. This essay understands erasure as a constraint-based appropriative practice and differentiates it from other forms of conceptual and documentary poetry. It argues that erasures use the oscillation between presence (of the retained words, the redaction marks and elisions, and the newly created poem) and absence (of some of the words and material and medial features of the prior text) to destabilize the boundaries between the published and unpublished, between what is heard and what is silenced, between the sayable and what exceeds representation. Reading poems by Tracy Smith, Janet Holmes, and Jen Bervin that erase the Declaration of Independence and the poetry of Emily Dickinson respectively, the essay shows how erasures intervene in public conversations about social justice by repurposing and revising their intertexts, allowing new speakers, knowledges, and narratives to emerge. Erasures prompt a layered reading that directs the readers back to the source and its sociocultural contexts while drawing them deeper into the imaginative and discursive world of the erasure poem.“Erasure poetry allows us to read in recognition of what is absent or missing and to imagine new voices and perspectives emerging from the cleared and transformed spaces of the page.”
Stackable Medical-Grade Skincare for the Cosmetic Medicine Patient: A Long-Term Pilot Assessment
Authors: Pryor Sydney , Semersky Alec , Sabev Tiffany , Few Julius
Published: May 2024

Background

Multiple intrinsic and extrinsic factors influence aging and lead to visible changes in the skin, including dryness, fine lines and wrinkles, loss of elasticity, surface roughness, uneven pigmentation, and loss of luminosity. Although it is well established that a single combination of topicals can address multiple signs of skin aging, it is common for patients’ at-home skin treatment routines to include multiple different topicals with different active ingredients. The layering of active ingredients can cause skin irritation, and lead to noncompliance with a consistent routine. Further, multiple active ingredients may exacerbate irritation from in-office aesthetic treatments.

Objectives

To assess the long-term efficacy, safety, tolerability, and patient adherence to a Stackable Treatment topical routine consisting of 4 complementary topical formulations.

Methods

This study examined a daily topical routine (Stackable Treatment routine) consisting of 4 topical formulas with different active ingredients, and evaluated the routine's safety, tolerability, and efficacy in a composite of in-office treatment patients who applied the routine for a minimum of 1 year.

Results

Of the 14 patients, 0 experienced adverse reactions. Improvements to multiple skin parameters were observed, including improvements to skin hydration, surface texture, pigmentation, vasculature, and the appearance of scars. The majority of patients continue to use the Stackable Treatment routine after the study's conclusion.

Conclusions

The combination of low incidence of irritation, high patient satisfaction, and overall efficacy of the routine indicates the Stackable Treatment routine may be well suited as a foundational skin care regimen that can complement in-office aesthetic treatments.

Level of Evidence: 4
Laparotomy for Traumatic Splenic Injury: Should we Increase our Efforts to Preserve the Spleen?
Authors: Jakob D A , Müller M , Kolitsas A , Exadaktylos A K , Demetriades D
Published: May 2024

Background

In trauma laparotomy the spleen is removed very liberally, and often little effort is made for splenic preservation.

Aims

The aim of this study was to assess the effect of surgical management (splenic repair vs. splenectomy) on outcomes in patients undergoing trauma laparotomy.

Methods

This is a trauma registry (TQIP) study (2013–2019), including adult patients with severe splenic injuries (grades III-V) undergoing trauma laparotomy. Characteristics and outcomes of patients who underwent splenic repair vs. splenectomy within 6 hours of admission were compared using different statistical approaches, i.e. 1:1 exact matching with consecutive conditional logistic regression analysis as primary analysis, multivariable logistic regression, propensity score matching and inverse-probability weighting as sensitivity analyses. The primary outcome was in-hospital mortality.

Results

A total of 11,247 patients with a severe splenic injury undergoing trauma laparotomy within 6 hours of admission were identified. Of these, 10,820 (96.2%) patients underwent splenectomy and 427 (3.8%) patients splenic repair within 6 hours of admission. Among patients who underwent an initial splenic salvage procedure, 23 (5.3%) patients underwent a splenectomy during the subsequent hospital stay. 400 patients with splenic preservation, were matched with 400 patients who underwent splenectomy (matched for age, sex, hypotension, trauma mechanism as well as AIS spleen grades 3,4,5 and AIS groups (AIS 0-2, AIS 3, AIS 4-5) for head, face, neck, thorax, spine, and lower & upper extremity). The mortality was significantly lower in the group of patients with splenic repair (6.5% vs 12.8%, p=0.002). The mortality benefit was subsequently verified by conditional regression analysis (aOR 0.4, CI 95% 0.2; 0.9). Multivariable logistic regression, propensity score matching, and inverse-probability weighting confirmed the lower mortality in the splenic repair group.

Conclusion

In trauma laparotomy splenic repair was independently associated with lower mortality compared with splenectomy. Splenectomy was required in approximately 5% of the patients after initial splenic repair. The findings provide evidence that efforts for spleen preservation in trauma laparotomy should be considered in selected cases.
Enough Is Enough – How Many Rectal Suction Biopsies Do You Need to Diagnose Hirschsprung’s Disease?
Authors: Metzger S , Neeser H R , Robbiani I , Rodewald A K , Nigbur T , Di Natale A , Moehrlen U , Tharakan S J
Published: May 2024

Background

Rectal suction biopsy (RSB) is the gold-standard for diagnosing Hirschsprung’s disease (HD) in infants. However, despite this being a common procedure no standard exists on how many biopsy specimens and at which level they should be taken.

Aims

The aim of this study is to determine the conclusiveness of RSB specimens in relation to their location within the rectum in diagnosing HD. With this, we would like to define how many specimens are necessary to diagnose HD and eventually propose a standardized protocol to conduct RSB.

Methods

We reviewed the epidemiological data and pathology results of 92 patients undergoing RSB between January 2011 and May 2022 at our institution. We perform RSB by taking 4 specimens at 1 cm, 3 cm and 5 cm above the dentate line, as well as one specimen at the dentate line.

Results

We included 92 patients who had 115 biopsies performed with a mean of 3.77 specimens per session. Of the specimens taken at 1 cm above the dentate line 73.9% were conclusive, at 3 cm 75.9% and at 5 cm 79.2%. Specimens taken at the dentate line were squamous or transitional epithelia in 31.5% and therefore of no use for HD diagnostics. If the specimen at 3 cm was conclusive, the whole session was more likely to be diagnostic.

Conclusion

We propose that taking a total of three specimens, namely one at 1 cm, one at 3 cm and further biopsy at 3 or 5 cm above the dentate line, is enough to diagnose or exclude HD.
Compatibility of Family Planning and Surgical Training in Switzerland
Authors: Faes S , Ferreirinha J , Weber M
Published: May 2024

Background

Surgeons undertake a long training and have stressful work schedules during optimal childbearing age. Training and career plans can entice young surgeons to renounce part-time work and delay pregnancy, risking pregnancy complications and infertility.

Aims

This survey study aims to determine the prevalence and constraints of part-time work and family planning among young surgeons in Switzerland.

Methods

An anonymous, voluntary survey was distributed to young board-certified surgeons. It queried work schedules and desire for part-time work as well as history of pregnancies and use of assisted reproductive treatment.

Results

A total of 375 surgeons participated, 308 were included (157 female, 151 male). There were no differences in current age (male median 37 (IQR 5), female 37 (6), p=0.93), median age at medical school graduation (male 26 (2), female 26 (2), p=0.90), and mean time to board certification (male 8.3 (SD 2.4), female 8.2 (SD 2.7), p=0.61). Female surgeons had a higher rate of part-time employment (38% vs 19%, p=0.0002). More male surgeons had children compared to their female counterparts (70% vs 45%, p<0.0001). Female surgeons were older (median 35 (IQR 4.5)) than male surgeons (median 33.5 (IQR 3.25), p=0.0002) and female partners of male surgeons (median 32 (IQR 3), p<0.0001) at birth of their first child. Female surgeons more frequently desired further children (71% vs 38%, p<0.0001) and delayed pregnancy due to training (74% vs 22%, p<0.0001). Female surgeons had longer time to conceive (>12 months 24% vs 10%, p=0.014), lower spontaneous pregnancy rates (82% vs 93%, p=0.029) and higher rates of assisted reproductive treatment (14% vs 4%, p=0.0089). Female surgeons more frequently perceived their gender as a negative career influence (67% vs 5%, p<0.0001).

Conclusion

Whilst part-time work and family planning are challenging for surgeons of both genders, female surgeons face striking inequities when trying to consolidate family planning with their profession.
Minimally-Invasive Robotic-Assisted Resection for Intrathoracic Goiter – A Feasible Alternative to Thoracotomy and Sternotomy
Authors: Hotz A S , Gelpke H , Zehnder A , Schmidt S , Goldmann A
Published: May 2024

Background

Goiter is a common presentation in daily clinical practice. It usually grows slowly and in rare cases with intrathoracic extension. There is no clear definition of intrathoracic goiters. The incidence in the literature varies from 3% to 7%. Most intrathoracic goiters are localized in the anterior mediastinum, with less than 25% are localized in the posterior mediastinum. This presents a challenge for surgical resection. Traditionally, the intrathoracic portions have been resected via sternotomy for anterior goiters and thoracotomy for posterior goiters. With the increasing use of robotic surgery, new possibilities for minimally invasive surgery and especially robotic procedures have emerged. This may reduce morbidity and length of hospital stay.

Aims

The study aims to show that minimal-invasive, robotic-assisted resection for intrathoracic goiter is safe and feasible.

Methods

During the study period from January 2021 to December 2023, 548 thyroid operations were performed in our clinic. All operations were prospectively recorded in the Eurocrine registry and retrospectively analyzed. Goiter was defined as intrathoracic according to perioperative findings (caudal border not visible on sonography and/ or further preoperative investigations ordered). Primary and secondary endpoints were outcome, conversion rate, and incidence of intrathoracic goiter.

Results

In our clinic, 19/548 patients (3.5%) presented with intrathoracic goiter. 17/19 patients were operated via conventional cervical approach. In 2 patients, minimal-invasive robotic mobilization of the large posterior portion of the goiter was performed in combination with conventional cervical thyroidectomy. No conversion was required. Based on our cases, we present robotic intrathoracic thyroid mobilization as a novel technique to avoid thoracotomy.

The rate of recurrent nerve palsy in intrathoracic goiter was 1/28 (3.5%) nerves at risk and occurred with conventional approach. No secondary bleeding or other complications were observed.

Conclusion

The minimal-invasive robotic approach seems to be a promising alternative to open procedures such as thoracotomy and can reduce morbidity and length of hospital stay.
High-Intensity Focused Ultrasound Therapy for an Osteoidosteoma in a Pediatric Finger: A Case Report
Authors: Hüppi J , Zechmann-Müller N , Binkert C
Published: May 2024

Background

High intensity focused ultrasound (HIFU) is a non-ionizing and non-invasive application for benign and malign disease. Ultrasonic waves are concentrated to achieve high level of energy and therefore necrosis due to coagulation.

Aims

We will describe one pediatric case where an osteoidosteoma war successfully treated by HIFU.

Methods

A seven-year-old boy presented in our department for hand surgery due to indolent swelling of the distal phalanx of the right ring finger. Neither recent trauma, nor positive family history was present. Clinical examination showed significant enlargement of the distal phalanx with minimal pain on palpation and unlimited mobility. Conventional radiography showed discrete fuzzy sclerosis of the metaphyseal part of the growth plate. MRI was not conclusive. Bone biopsy showed reactive change with no signs for acute inflammatory event. Periodic checks were performed, with no change in clinical and radiographic aspect. Nine months after the first appointment, the patient presented with pain after minor trauma and increase of the swelling. Radiography showed a nidus in the distal phalanx leading to a suspected diagnosis of an osteoidosteoma. Therefore, MRI-guided HIFU (MR-HIFU) was recommended one year after the first appointment.

Results

MR-HIFU was performed to destroy the osteoidosteoma. Six months after the intervention the patient presented with no further exponential growth and the difference to the other phalanges was minimized. Furthermore, radiography showed no retention of the nidus with a plane distal phalanx.

Conclusion

MR-HIFU is a promising approach in the non-invasive treatment of tumorous neoplasm. Because of its non-ionizing ultrasonic waves, there is no upper limit in dosing. The deposition of heat is in general limited by the surrounding tissue. The main factors preventing MR-HIFU treatment are thick bone around the nidus, a superficial position with risk for skin burn and the vicinity to neural structures. Osteoidosteomas are generally rather small and therefore well suited for MR-HIFU.
Preoperative MRCP is not Associated with Lower Complication Rates but Shorter Hospital Stay in Laparoscopic Cholecystectomy
Authors: Zeindler J , Hess G F , Sedlaczek P , Muenst S , Bolli M , Kollmar O , Soysal S D
Published: May 2024

Background

Laparoscopic cholecystectomy is a very common procedure and while preoperative magnetic resonance cholangiopancreatography (pMRCP) is widely used for detection of choledocholithiasis and preoperative planning, the benefits in patients with normal preoperative cholestatic parameters remain unclear.

Aims

We aimed to investigate a large cohort of patients after laparoscopic cholecystectomy to analyse the impact of pMRCP on complication rates.

Methods

This retrospective cohort study consecutively includes all patients receiving elective or acute laparoscopic cholecystectomy between 2010 and 2020. Exclusion criteria were conversion to open cholecystectomy and preoperatively elevated cholestatic parameters. Complication rates were recorded and patients stratified depending on the use of pMRCP for preoperative planning.

Results

3163 patients underwent laparoscopic cholecystectomy between 2010 and 2020, 2568 of which showed normal cholestatic parameters preoperatively. Of these patients, 684/2568 (27%) were male and 1884/2568 (73%) female. The most frequent indications for laparoscopic cholecystectomy were cholecystolithiasis in 72% (1845/2568) of cases, followed by cholecystitis in 18% (465/2568). The majority of patients (2267/2568, 88%) indeed received pMRCP, while the remaining 301/2568 patients did not. Postoperative complication rates did not significantly differ between the two groups (396/2267 (17%) in the pMRCP group and 58/301 (19%) without pMRCP, p=0.469). One case of pancreatitis occurred in the pMRCP group, versus two reported cases in the other group. Interestingly, the length of hospital stay after cholecystectomy was significantly shorter in the group with pMRCP versus without (4 days (range 1-61 days) versus 7 days (range 1 – 66 days), respectively, p = 0.023).

Conclusion

Preoperative MRCP seems to not prevent complications in laparoscopic cholecystectomy, since postoperative complication rates were comparable between the two patient groups with and without pMRCP. However, postoperative hospital stay was significantly shorter in patients undergoing pMRCP compared to patients without pMRCP.
Evaluation of the Low Anterior Resection Syndrome and Quality of Life in Patients Having Undergone Sphincter Sparing Rectal Cancer Surgery
Authors: Fiechter J , Sguinzi R , Bafumi L , Gremaud B , Geng B , Bühler L , Egger B
Published: May 2024

Background

In order to avoid abdomino-perineal amputation and permanent colostomy in patients with low rectal cancer sphincter sparing low anterior resection (SSLAR) techniques with/without neoadjuvant radio-chemotherapy are administered. However, a lot of SSLAR-patients have life quality limiting symptoms afterwards, like fecal urgency, incontinence, constipation and sensation of incomplete rectal emptying. Such symptoms are defined as “low anterior resection syndrome” (LARS). LARS quantification can be made by a specific and validated quality of life (QoL) questionnaire (see annex).

Aims

Assessment of the QoL in patients after SSLAR suffering from LARS before and after specific therapy.

Methods

This is a monocentric, retrospective cohort study including patients having undergone SSLAR for rectal cancer 2014 - 2021. Initial LARS-scores were obtained by completion of the specific questionnaire. Patients with a minor LARS (scores 21-29) were treated with electrostimulation and bio-feedback physiotherapy. Those with a major LARS (scores >29) were first investigated by anal manometry followed by physiotherapy. After treatment LARS-scores were obtained again.

Results

Of 136 identified SSLAR-patients, 68 did not fulfill the inclusion criteria’s (see annex). Of the remaining 54 patients, 20.4% had a minor, 37% a major and 42.6% no LARS. Of all LARS-patients, 13 completed pelvic physiotherapy, 4 are still completing and 14 (26%) refused such a treatment. The mean-LARS score was 32.77 and 22.92, before and after treatment, respectively (p=0.004). Risk factor analysis (diabetes, type of anastomosis, neoadjuvant radio-chemotherapy, previous operations, nicotine, alcohol) did not reveal any significant difference between groups.

Conclusion

More than 50% of patients undergoing SSLAR are suffering from LARS, more than one third from major LARS. QoL is impressively improved by specific physiotherapeutic measures. In order to avoid later treatment hesitancy (26%), we began to initiate early specific physiotherapy as a standard in all SSLAR-patients.
Impact of Virtual Reality Distraction on Pain and Anxiety for Bedside Abdominal VAC Dressing Change (VIRPA) – A Randomized Controlled Clinical Trial
Authors: Barberá Carbonell B , Hübner M , Grass F , Djafarrian R
Published: May 2024

Background

Virtual reality (VR) distraction techniques are promising adjuncts to reduce pain and anxiety.

Aims

This study assessed the impact of VR distraction during bedside change of vacuum assisted closure (VAC) dressings.

Methods

In this non-blinded randomized superiority trial, patients scheduled for bedside change of a subcutaneous VAC dressing were allocated to receive distraction through VR masks in addition to a standardized pain protocol (intervention) or pain protocol alone (control). Primary endpoints were pain scores assessed by a visual analogue scale (VAS:0-10), secondary outcomes were anxiety (State Trait Anxiety Inventory (STAI-Y:20-80), VAS:0-10), hemodynamic parameters and satisfaction (VAS:0-10).

Results

Nineteen and twenty-one patients were randomized to receive intervention and control, respectively. Baseline characteristics were well balanced including age (61±11 vs. 62±17), sex (female: 9 vs. 13), American Society of Anesthesiologists (ASA) scores (≥3: 18 vs. 18, all non-significant). Pre- and postoperative pain levels were 2.2±2.2 vs. 2.0±2.1 (p=0.38) for the intervention group compared with 2.6±2.1 vs. 2.2±1.6 (p=0.26), with no significant difference between the groups (p=0.38). Similar findings for blood pressure and heart rates. Anxiety was reduced in both groups post VAC change in the intervention and control group: STAI 40±12 pre-VAC vs. 30±8 post VAC and 45±14 pre-VAC vs. 32±9 post VAC (both p<0.01), ΔVAS -2 (interquartile range IQR 0, -3) vs. -2 (IQR 0, -5), both p<0.01. Postinterventional satisfaction was 8.3±1.9 (intervention) vs. 7.5±2.4 (p=0.11).

Conclusion

In this study, pain and anxiety were well managed with a standardized pain protocol with or without adjunct VR distraction. Further studies will focus on patients with insufficient control of pain and anxiety with a standard protocol.
Milestones in Surgical Complication Reporting – Twenty years of Clavien-Dindo Classification & ten years of Comprehensive Complication Index (CCI®)
Authors: Abbassi F , Pfister M , Domenghino A , Lucas K L , Puhan M A , Clavien P A
Published: May 2024

Background

Standardized outcome reporting is key for proper assessment of surgical procedures. A recent consensus conference recommended the Clavien-Dindo classification (CDC) and the Comprehensive Complication Index (CCI®) for assessing postoperative morbidity. However, their use in randomized controlled trials (RCTs) has not been assessed, and several challenging scenarios for grading complications require consensus-based guidance.

Aims

The aim of this study was to assess the use of the CDC and CCI® in RCTs and to provide guidance on their standardized and consistent application.

Methods

We identified all RCTs that used the CDC or CCI® as a primary or secondary outcome.

In addition, we asked 163 international surgeons to independently grade complications of 20 clinical cases covering seven challenging scenarios. Finally, a core group of five experts used this information do develop consistent recommendations.

Results

Up to July 2023, 1424 RCTs used the CDC or CCI® to assess postoperative morbidity. Annual use was steadily increasing with now over 200 new RCTs per year.

Eighty-nine (55%) surgeons completed the survey. Complications requiring multiple interventions, complications of complications, complications occurring prior to referral, and expected and unrelated complications should all be counted as separate complications and included in the CCI®. Invasive diagnostics without findings should not be considered as a complication since purely diagnostic.

Conclusion

We observed an extensive and steadily increasing use of CDC and CCI® in RCTs, highlighting the importance of their consistent application. Provided by the original developers of the CDC and CCI® and based on an international survey of their frequent users, the current consensus offers much-needed guidance for challenging scenarios. This will further improve the consistency and accuracy of complication reporting, leading to higher quality RCTs, improved cost estimations, and better quality control, ultimately benefiting all stakeholders.
Air-Leak-Management Supported by Ventilation-SPECT/CT: A New Perspective on a Long-Known Problem
Authors: Gelpke H , Guglielmetti L , Nagel H , Klaeser B , Zehnder A
Published: May 2024

Background

Prolonged air leakage (PAL) is a common problem after lung surgery. Localization of air leaks (AL) remains challenging in some cases especially in minimally invasive surgery. Ventilation-SPECT/Computertomography (vSPECT/CT) has been reported as potential aid to identify and localize AL.

Aims

To evaluate vSPECT/CT as potential aid for the localization of AL and explore its use as support for PAL management.

Methods

Retrospective analysis of a case series of seven patients with PAL after minimally invasive thoracic surgery at our institution in 2023 for which vSPECT/CT was applied.

Results

Six patients underwent oncologic lung resections, one patient underwent thymectomy for a thymoma. In 5/7 cases an AL was spotted with vSPECT/CT (maximal AL ranged from 40-2000 ml/min). In the remaining two cases (with a maximal AL of 1900ml/min for 1 day, and 10 ml/min after more than 4 weeks and continuous clinical signs of PAL), the AL could neither be localized during revision surgery.

Nevertheless, the AL ceased in all patients after revision surgery. In two cases the detected AL supported the continuance of conservative treatment as it confirmed a leak within the prior resection site (maximal AL 40ml/min and 200ml/min). These results are depicted in the attached visual abstract.

Conclusion

The use of vSPECT/CT for localizing ALs proved to be precise in all instances where an imaging spot was observed (5/5 cases). Additionally, in the two cases where no spot was detected, no AL was found during subsequent revision surgery. These initial results are promising and support further prospective studies of a broader group of cases, reinforcing the role of vSPECT/CT as valuable aid in managing PAL.
Loco-Regional Ropivacaine Analgesia Via a Surgically Placed Intercostal Catheter after Anatomic Lung Resection: Prospective, Placebo-Controlled, Double-Blind; Randomized Superiority Trial
Authors: Hojski A , Krämer M , Gecas P , Bolliger D , Lampart A , Lardinois D
Published: May 2024

Background

Even after minimally invasive anatomic lung resection, pain remains a burden for patients. Current guidelines recommend the surgical placement of intercostal catheters at the end of the surgery to promote faster recovery after lung surgery.

Aims

The aim of this trial was to investigate the analgesic efficacy of continuous loco-regional application of ropivacaine via an intercostal catheter and to establish this method as a possible standard of care in postoperative analgesia management.

Methods

Between December 2021 and October 2023, we evaluated the efficacy of surgically inserted intercostal catheters. Patients were eligible when undergoing anatomic VATS lung resection under general anesthesia for confirmed or suspected stage I lung cancer (UICC, 8th edition). Patients received ropivacaine at a concentration of 2 mg/ml or a placebo through an elastomer pump, flow rate of 6-8 ml/h for 72 hours after surgery. The sample size was calculated to find an NRS (numerical rating scale) difference associated with a pain reduction of 1.5 points.

Results

14 patients were randomly included in the ropivacaine group and 18 in the placebo group. The patients’ characteristics and preoperative pain scores were similar in both groups.

Between the observed groups there was no statistically significant difference in postoperative pain scores and morphine consumption. The NRS score for cough 24 hours postoperatively was 4.9 (±2.2) in the ropivacaine group and 4.3 (±2.4); p=0.474 in the placebo group. In addition, we were unable to determine any influence of the pain management on the relative postoperative pulmonary function.

Conclusion

Our results suggest that the analgesic efficacy of continuous loco-regionally applied ropivacaine administered through a surgically placed intercostal catheter after surgery does not have a positive effect on postoperative pain scores or morphine requirements. Instead, local analgesia started at the beginning of the procedure and covering several intercostal spaces should be considered.
Potential Advantage of Magnetic Resonance Imaging in Detecting Thoracic Wall Infiltration in Pleural Mesothelioma. A Retrospective Single Center Analysis.
Authors: Barreto I , Franckenberg S , Frauenfelder T , Opitz I , Lauk O
Published: May 2024

Background

Thoracic wall infiltration in pleural mesothelioma (PM) can be an important prognostic factor when determining the extent of resection. Currently, standardized imaging for restaging after neoadjuvant systemic therapy comprises contrast enhanced Computed Tomography (CT) or Positron Emission Tomography (PET/CT) scan.

Aims

However, thoracic Magnetic Resonance Imaging (MRI) could be a better discriminator of chest wall infiltration prior to surgery. To increase the preoperative staging accuracy, we introduced a MRI protocol at our center.

Methods

A retrospective analysis of this prospective new imaging protocol was performed from 07/2018 to 08/2023, including descriptive analysis for patient`s sex, age, nicotine consumption, asbestos exposure, histological subtype, TNM-stage, RECIST criteria and number of neoadjuvant therapy cycles. Preoperative restaging included routine imaging and MRI. After histological diagnosis of PM, neoadjuvant therapy was conducted, followed by partial pleurectomy or extended pleurectomy/decortication, with intraoperative biopsies of suspicious chest wall lesions. The CT/MRI results were compared to the intraoperative biopsies. Sensitivity and specificity of both modalities were analyzed.

Results

Twenty-five patients (mean age 65.4, 12% female) with possible chest wall infiltration were included out of the 35 patients with PM treated during the observation period. Of the 10 patients with actual chest wall infiltration, 9 (90%) had a T-Stage of 3 or higher, 9 (90%) had PM of epithelioid histologic subtype and 4 (40%) a R2-Resection. The mean overall survival of all patients was 18.88 months (8-58).

In our study, thoracic MRI showed a high sensitivity (90%) and specificity (100%) for the detection of chest wall infiltration, especially when compared to the CT scan (sensitivity of 10%).

Conclusion

With the adjunctive use of thoracic MRI we demonstrated a higher sensitivity for detection of chest wall infiltration compared to conventional imaging prior to surgery. This may facilitate the preoperative assessment of the extent of resection. Nevertheless, larger studies are required to confirm these results.
Association Between Documented Intraoperative and Postoperative Adverse Events: An Analysis of Over 100,000 Surgical Trauma Cases
Authors: Mittlmeier A , Canal C , Dell-Kuster S , Pape H C , Neuhaus V
Published: May 2024

Background

Intraoperative adverse events (iAEs) are common during surgical procedures. However, structured and comparable documentation often depends on the physician’s subjective assessment of each iAE.

Aims

The aim of this study was to validate the hypothesis that iAEs during surgical interventions are clearly associated with further postoperative complications and prolonged hospital stays.

Methods

We performed a retrospective analysis comparing surgical patients with and without any iAEs regarding postoperative outcomes during the hospitalization. We analyzed more than 100,000 patients with surgically treated injuries between January 2012 and December 2022 from over 70 institutions across Switzerland. Outcome parameters were further compared using a 1:1 case-control matching method, while controlling for same age, gender, main diagnosis and procedure.

Results

Regarding outcomes, patients with iAEs had a significantly longer duration of surgery (131 vs. 77 minutes), a prolonged length of hospital stay (10 vs. 8 days), a significantly higher need for an intensive care unit (ICU) stay of more than one day (7% vs. 3%), and a significantly higher rate of postoperative and procedure-associated complications (28% vs. 7%) than those without iAEs. The prolonged duration of surgery, length of stay, and postoperative and procedure-associated complications in the iAE group were also confirmed in the matched-pair analysis to be associated with poorer patient outcomes while controlling for significant characteristics.

Conclusion

In line with the current literature, our data show a clear relevance of iAEs as crucial factors for patient outcomes, manifesting in significantly longer durations of surgery, prolonged lengths of stay, and more postoperative complications, in a broad spectrum of surgical trauma procedures. We propose the mandatory documentation of iAEs through a standardized classification system, such as ClassIntra, and in accordance with the Intraoperative Complications Assessment and Reporting with Universal Standards (ICARUS) guidelines for clinical practice and surgical research.
Endovascular Arch Repair of Anastomotic Aneurysm and Pseudoaneurysm in Patients after Open Repair of the Ascending Aorta and Aortic Arch: A Case Series
Authors: Becker D , Stana J , Prendes C F , Konstantinou N , Öz T , Pichlmaier M , Peters S , Tsilimparis N
Published: May 2024

Background

Endovascular techniques have provided new options in the treatment of arch pathologies. Multiple studies have reported good results after endovascular treatment of aortic arch aneurysms and it has developed to be a considerable approach, especially in patients who are unfit for open surgery. In treatment of progressing distal pathologies after open ascending aorta and/or aortic arch replacement, the endovascular arch repair has shown promising results.

Aims

Aim of study was to investigate the outcomes of endovascular arch repair (b-TEVAR) with a custom-made double or triple branched arch endograft in patients with distal anastomotic aneurysms after open repair of the ascending aorta or proximal arch replacement.

Methods

Retrospective analysis was conducted of all consecutive patients with anastomotic aneurysms after open surgical repair involving the ascending aorta and/or aortic arch treated with b-TEVAR. All patients were treated with a custom-made double or triple inner-branched arch endograft. Study endpoints were technical success, 30-day and follow up mortality/ morbidity and re-interventions.

Results

Between 2018 and 2022, ten patients were treated with custom-made double or triple branched TEVAR due to anastomotic aneurysms after open ascending aorta and/or proximal aortic arch replacement. Eight patients received a triple and two a double arch branched endograft. Eight cases were performed electively and two urgently for contained rupture. Technical success was achieved in nine cases (90%). All elective patients survived. Two patients treated due to contained ruptures expired. Within 30 postoperative days, one transient ischemic attack occurred. No early endograft-related re-interventions were necessary. Median follow-up was 20 months. One patient died two months after discharge due to sepsis caused by pneumonia. No further deaths or endograft-related re-interventions were observed.

Conclusion

Endovascular aortic arch repair with double or triple inner-branched arch endograft for anastomotic aneurysms after open ascending and/or proximal arch replacement is technically feasible and a promising alternative in a patient cohort unfit for surgery.
Infective Native Aortic Aneurysms: A Delphi Consensus Document on Terminology, Definition, Classification, Diagnosis, and Reporting Standards
Authors: Wyss T , Sörelius K
Published: May 2024

Background

There is no consensus regarding the terminology, definition, classification, diagnostic criteria, and algorithm, or reporting standards for the disease of infective native aortic aneurysm (INAA), previously known as mycotic aneurysm.

Aims

The aim of this study was to establish this by performing a consensus study.

Methods

The Delphi methodology was used. Thirty-seven international experts were invited via mail to participate. Four two-week Delphi rounds were performed, using an online questionnaire, initially with 22 statements and nine reporting items. The panellists rated the statements on a five-point Likert scale. Comments on statements were analysed, statements revised, and results presented in iterative rounds. Consensus was defined as ≥ 75% of the panel selecting “strongly agree” or “agree” on the Likert scale, and consensus on the final assessment was defined as Cronbach's alpha coefficient > .80.

Results

All 38 panellists completed all four rounds, resulting in 100% participation and agreement that this study was necessary, and the term INAA was agreed to be optimal. Three more statements were added based on the results and comments of the panel, resulting in a final 25 statements and nine reporting items. All 25 statements reached an agreement of ≥ 87%, and all nine reporting items reached an agreement of 100%. The Cronbach's alpha increased for each consecutive round (round 1 = .84, round 2 = .87, round 3 = .90, and round 4 = .92). Thus, consensus was reached for all statements and reporting items.

Conclusion

This Delphi study established the first consensus document on INAA regarding terminology, definition, classification, diagnostic criteria, and algorithm, as well as reporting standards. The results of this study create essential conditions for scientific research on this disease. The presented consensus will need future amendments in accordance with newly acquired knowledge.
PERCUTANEOUS LEFT STELLATE GANGLION BLOCK TO INCREASE VENTRICULAR FIBRILLATION THRESHOLD AND DEFIBRILLATION SUCCESS RATE IN ACUTE FULMINANT MYOCARDITIS WITH ELECTRICAL STORM
Authors: Morena A , Gravinese C , Frea S , Angelini F , Boretto P , Gallone G , De Lio G , Bocchino P , Zanierato M , Tore D , Barreca A , Raineri C , Pidello S , De Ferrari G , Dusi V
Published: May 2024

Introduction

Acute fulminant myocarditis represents a predisposing substrate for life–threatening ventricular arrhythmias (VAs). Percutaneous left stellate ganglion block (PLSGB) usage has been reported for the prevention of recurrent VAs, but clinical data on its acute effect on ongoing ventricular fibrillation (VF) are missing.

Case

A 57–years–old man suffering gastroenteritis and fever in the past week presented in the ED with typical chest pain. ECG depicted infero–lateral ST–segment elevation, cardiac ultrasound showed a mildly reduced LVEF and coronary angiography ruled out coronary lesions. In the following hours the patient developed frequent premature ventricular complexes with R on T phenomenon triggering short coupled torsade de pointes with rapid degeneration into VF. VAs episodes, initially responsive to single DC shock, kept recurring despite intravenous (iv) amiodarone, iv lidocaine and iv correction of potassium and magnesium. The patient was therefore treated with deep sedation, intubation and ECMO VA placement; still, he reached a status of persistently ongoing VF, refractory even to DC shocks (n=20). Therefore, ultrasound–guided PLSGB using a local bolus of lidocaine 150 mg + ropivacaine 50 mg was performed. After 5 minutes, a single DC shock was delivered, effective in achieving a stable sinus rhythm at 35 bpm with no more recurrences. Despite electrical stabilization, the patient developed a severe cardiogenic shock due to bradycardia and severe biventricular disfunction, treated with vasopressin and dobutamine. In the next 48 hours we observed a significant improvement, resumption of biventricular contractility and absence of VAs recurrences, so the patient was slowly weaned off ECMO and vasopressors. Immunological tests showed Enterovirus IgM positivity, while endomyocardial biopsy was negative for inflammatory infiltrates in the analyzed sections. Cardiac MRI (performed 10 days after onset) showed edema and non–ischemic LGE in the antero–lateral and infero–lateral basal subepicardial regions of the left ventricle, LVEF was 55%. After 15 days from admission, despite ongoing amiodarone and bisoprolol, the patient developed a run of monomorphic VA of 30 beats at 170 bpm, therefore he underwent sICD implantation.

Conclusion

PLSGB played a key role for the acute management of refractory VF unresponsive to DC shocks, allowing for acute stabilization. More clinical data are needed on acute neuromodulation for electrical storm.