How should we secure the cystic duct during laparoscopic cholecystectomy? A UK-wide survey of clinical practice and systematic review of the literature with meta-analysis

INTRODUCTION

It is currently unknown which method of cystic duct closure is most effective at reducing the risk of bile leak after laparoscopic cholecystectomy. The aims of this work were to determine the most common closure methods used in the UK and review available evidence on which method has the lowest risk of bile leak.

METHODS

We conducted an online survey through the Association of Upper Gastrointestinal Surgeons (AUGIS). We also undertook a systematic review using PubMed, EMBASE, MEDLINE and the Cochrane Library for studies that compared different methods for cystic duct occlusion and reported postoperative bile leak.

FINDINGS

There was significant variation in practice between consultant surgeons. For routine laparoscopic cholecystectomy metal clips were used most (64%) followed by locking polymer clips (33%) and suture ties (3%). In cases of a dilated cystic duct, preferences were locking polymer clips (60%), suture ties (30%) and metal clips (5%). We included six studies in our review with a total of 8,011 patients. Metal clips were associated with an increased odds of bile leak compared with locking polymer clips (OR 5.66, 95% CI 1.13-28.41, p=0.04) or suture ties (OR 4.17, 95% CI 0.72-24.31, p=0.12). Most studies were retrospective, unlikely to be adequately powered, and vulnerable to selection bias.

CONCLUSIONS

Limited available evidence suggests that metal clips have the highest risk of bile leak, but results are not strong enough to recommend a change in current clinical practice. A trial is now required to determine the best method of cystic duct closure.

Imaging Breast Microcalcifications Using Dark-Field Signal in Propagation-Based Phase-Contrast Tomography

Breast microcalcifications are an important primary radiological indicator of breast cancer. However, microcalcification classification and diagnosis may be still challenging for radiologists due to limitations of the standard 2D mammography technique, including spatial and contrast resolution. In this study, we propose an approach to improve the detection of microcalcifications in propagation-based phase-contrast X-ray computed tomography of breast tissues. Five fresh mastectomies containing microcalcifications were scanned at different X-ray energies and radiation doses using synchrotron radiation. Both bright-field (i.e. conventional phase-retrieved images) and dark-field images were extracted from the same data sets using different image processing methods. A quantitative analysis was performed in terms of visibility and contrast-to-noise ratio of microcalcifications. The results show that while the signal-to-noise and the contrast-to-noise ratios are lower, the visibility of the microcalcifications is more than two times higher in the dark-field images compared to the bright-field images. Dark-field images have also provided more accurate information about the size and shape of the microcalcifications.

Glycated haemoglobin and the risk of postoperative complications in people without diabetes: a prospective population-based study in UK Biobank

The aim of our study was to clarify the association between glycated haemoglobin (HbA1c ) and postoperative outcomes in people without an existing diagnosis of diabetes. Half a million adults were recruited into the UK Biobank prospective cohort study between March 2006 and October 2010. We divided participants into three groups: no diagnosis of diabetes and HbA1c  < 42 mmol.mol-1 ; no diagnosis of diabetes and elevated HbA1c (≥ 42 mmol.mol-1 with no upper limit); and prevalent diabetes (regardless of HbA1c concentration) at recruitment. We followed up participants by linkage with routinely collected hospital data to determine any surgical procedures undertaken after recruitment and the associated postoperative outcomes. Our main outcome measure was a composite primary outcome of 30-day major postoperative complications and 90-day all-cause mortality. We used logistic regression to estimate the odds of the primary outcome by group. We limited analyses to those who underwent surgery within one year of recruitment (n = 26,653). In a combined effects logistic regression model, participants not known to have diabetes with HbA1c  ≥ 42 mmol.mol-1 had increased odds of the primary outcome (OR [95% CI] 1.43 [1.02-2.02]; p = 0.04), when compared with those without diabetes and HbA1c  < 42 mmol.mol-1 . This effect was attenuated and no longer statistically significant in a direct effects model with adjustment for hyperglycaemia-related comorbidity (OR [95% CI] 1.37 [0.97-1.93]; p = 0.07). Elevated pre-operative HbA1c in people without diabetes may be associated with an increased risk of complications, but the association is likely confounded by end-organ comorbidity. In contrast to previous evidence, our findings suggest that to prevent adverse postoperative outcomes, optimisation of pre-existing morbidity should take precedence over reducing HbA1c in people without diabetes.

Coalescence of Anderson-localized modes at an exceptional point in 2D random media

In non-Hermitian settings, the particular position at which two eigenstates coalesce in the complex plane under a variation of a physical parameter is called an exceptional point. An open disordered system is a special class of non-Hermitian system, where the degree of scattering directly controls the confinement of the modes. Herein a non-perturbative theory is proposed which describes the evolution of modes when the permittivity distribution of a 2D open dielectric system is modified, thereby facilitating to steer individual eigenstates to such a non-Hermitian degeneracy. The method is used to predict the position of such an exceptional point between two Anderson-localized states in a disordered scattering medium. We observe that the accuracy of the prediction depends on the number of localized states accounted for. Such an exceptional point is experimentally accessible in practically relevant disordered photonic systems.

Analysis of Unsteady Magnetohydrodynamic 3-D Rotating Flow and Transfer of Heat in Carbon Nanotube-Water Nanofluid: An Engineering Application

We have analysed unsteady Magnetohydrodynamic (MHD) 3-D rotating flow of Carbon Nanotube (CNT) water nanofluid past a stretching surface dealing with thermal radiation mechanism of heat transfer and heat source/sink. The mathematical model consists of a system of non-linear coupled Partial Differential Equations (PDEs). Numerical solution is obtained and discussed in detail. The influence of flow dominant parameters on the temperature profiles and flow-field are also discussed in detail using tables and graphs. Results are justified by previously published results in the limiting sense. Various crucial results are obtained, for example, unsteadiness parameter accelerates the fluid velocities in both directions near the sheet and reverse behaviour is noticed away from the sheet. However, fluid rotation causes reduction in primary velocity but it tends to accelerate secondary velocity near the sheet. Insertion of nanoparticle volume fraction intensifies fluid velocity and attenuates fluid temperature. We also found that multi-Walled Carbon Nanotubes (MWCNTs) offer more resistance for primary skin friction and less resistance for secondary skin friction when compared with Single-Walled Carbon Nanotubes (SWCNTs).

60 Neoadjuvant Imatinib Mesylate – an Ace of Spaces for Surgical Management of an Oesophago-Gastric Junction Gastro-Intestinal Stromal Tumour

Introduction

Oesophageal gastro-intestinal stromal tumours (GISTs) are rare, accounting for less than five percent of all GIST, with the majority of these occurring at the oesophago-gastric junction (OGJ). Due to the anatomical location and size of these tumours at presentation, surgical resection is often a major undertaking.

Neoadjuvant treatment with tyrosine kinase inhibitors, such as Imatinib mesylate, have the potential to downstage such tumours, thereby limiting the extent of subsequent surgical resection. This may therefore reduce any potentially associated morbidity and mortality.

Case Description

We report the case of a 75-year-old gentleman who presented with a large OGJ GIST, which presented with dysphagia. The tumour was deemed too large for local excision due to the risk of compromising the lumen at the OGJ in attempting to obtain a clear resection margin. Given the patient’s co-morbidity, oesophagectomy or total gastrectomy was deemed too major an undertaking. Therefore, endoscopic biopsies were obtained with a view to possible neoadjuvant therapy. These confirmed DOG-1 and Exon-11 mutations, suggesting sensitivity to Imatinib mesylate. A standard dose regime of 400mg daily for a planned 36-month course was commenced. Subsequent imaging showed a substantial decrease in tumour bulk and the decision was made to perform a local excision. A local enucleation procedure was performed, and the patient made a sound recovery.

Post-operative histology of resected tumour showed almost complete tumour regression.

Discussion

This significant response to neoadjuvant Imatinib mesylate therapy demonstrates clear potential for its use in similar cases, where radical resection would cause significant morbidity and risk mortality.

43 The Value of Endoscopic Ultrasound (EUS) in the Investigative Pathway of Acute Idiopathic Pancreatitis (AIP)

Introduction

The British Society of Gastroenterology (BSG) guidelines on the management of acute idiopathic pancreatitis (AIP) state the incidence of idiopathic cases to be no more than 30%. However, before a firm diagnosis of AIP is made, Endoscopic Ultrasound (EUS) may be used to determine occult causes. This approach may help prevent recurrent attacks which may evolve into chronic pancreatitis.

Method

Retrospective analysis over a one-year period of cases of AIP in a tertiary referral centre was performed to see the incidence of AIP and the role of EUS. Patients with an identifiable cause for pancreatitis were excluded, leaving only those who had received a diagnosis of AIP and the diagnostic value of EUS was examined.

Results

Of the 101 patients diagnosed with AIP, 19% (n=19) underwent an EUS successfully. 79% (n=15) had no underlying cause of pancreatitis identified on EUS. In the remaining 21% of cases (n=4), microlithiasis, ductal stones, and pus requiring drainage were common findings. Of these patents, only 1 was referred for surgery. In the patient group with negative findings on EUS, 4% were unaffected, 2% were referred for surgery, 2% died and 7% had recurrent episodes of pancreatitis.

Conclusions

The results of this study show that EUS is a valuable modality in patients with suspected AIP, with a positive diagnostic rate of 21%. Therefore, we propose EUS needs to be included in the investigative pathway of all suspected AIP. Although EUS is a relatively scarce resource, further research is required to establish guidelines for the investigation of suspected AIP.

Methotrexate in erythema nodosum leprosum: Pitfalls to avoid

We read with interest the short report by Rani et al. entitled "An uncommon variant of erythema nodosum leprosum responding well to methotrexate: Report of two cases." The article describes two cases of erythema nodosum leprosum (ENL) with 'atypical features' and good response to low dose methotrexate. The authors address a few concerns regarding methotrexate in ENL, emphasizing the rational usage of this agent.

Country Experience with using the Country Assessment Tool (Lessons learned)

Findings from the CA show that research and data are largely available, but there are several knowledge gaps and we often lack a comprehensive overview. Gaps include longitudinal studies and knowledge of effects of implemented policy and practice. Lack of knowledge-based practice and policy development is a continuous challenge. Furthermore, we identified a lack of coordination of the migration health field, as well as cross-sectional collaboration.

Lessons learned: The CA and the JAHEE has provided a starting point for conversations with national partners, such as the directorate of health, about how we can strengthen the migration and health field in Norway. The CA has been presented and used in national conferences to highlight gaps and initiate collaboration to mitigate these gaps. The CA tool can become the comprehensive overview that we do not have today. While MIPEX covers integration policy, the CA covers broader topics touching on the work carried out in different sectors and levels in society that affect migrant health.

The Country Assessment Tool - process of development and use

The objective of the Country Assessment (CA) is to give an overview of the migration and health field in the partners' countries. Having an overview of the complex migration and health field enables partners to identify entry points for implementing actions to reduce inequities in migrant's health. The Country Assessment (CA) was based on findings from the projects first deliverable “Policy Framework for Action” (PFA). The PFA mapped key international policy documents between 2007 and 2018. We reviewed and extracted a coherent synthesis we called the ‘Road Map'. The synthesis identified six main areas that is covered in the CA tool: 1) Data and research 2) Governance and leadership 3) Intersectoral action 4) Health Service Responsiveness 5) Migrants access to health services 6) vulnerable groups. The Country Assessment template was piloted by two partner countries, Norway and Italy. The template was revised until all partners were satisfied with the range of questions. Partners then filled in readily available information and examples of available data and policy in their country.

Impact of COVID-19 on migrant populations in high-income countries: a systematic review

Background

Migrants in high-income countries (HICs) may have been disproportionately affected by the COVID-19 pandemic, yet the extent to which they are impacted, and their predisposing risk factors, are not clearly understood. We did a systematic review to assess clinical outcomes, indirect health and social impacts, and key risk factors in migrants.

Methods

Our systematic review following PRISMA guidelines (PROSPERO CRD42020222135) identified peer-reviewed and grey literature relating to migrants (foreign-born) and COVID-19 in 82 HICs. Primary outcomes were cases, hospitalisations and deaths from COVID-19 involving migrants; secondary outcomes were indirect health and social impacts and risk factors.

Results

3016 data sources were screened with 158 from 15 countries included in the analysis. We found migrants are at increased risk of SARS-CoV-2 infection and are over-represented among cases (e.g. constituting 42% of cases in Norway [to 27/4/2020], 26% in Denmark [to 7/9/2020], and 32% in Sweden [to 7/5/2020]); some datasets from Europe show migrants may be over-represented in deaths with increased all-cause mortality in migrants in some countries in 2020. Undocumented migrants, migrant health and care workers, and migrants housed in camps have been especially affected, with certain nationality groups disproportionately impacted. Migrants experience a range of risk factors for COVID-19, including high-risk occupations, overcrowded accommodation, and barriers to healthcare including inadequate information, language barriers, and reduced entitlement.

Conclusions

Migrants in HICs are at high risk of COVID-19, with a range of specific risk factors that have not been well-considered in the public health response to date. These data are of immediate relevance to the policy response to the pandemic, with strategies urgently needed to reduce transmission. Migrant populations must also be better considered in national plans for COVID-19 vaccination roll-out.

On behalf of ESGITM

Key messages

Migrants in high-income countries may be disproportionately represented in COVID-19 infections and deaths, with higher levels of many vulnerabilities and risk factors.

Migrants must be better included in all aspects of the pandemic response, including vaccination roll-out.

The Bergen Declaration 2018: Did it drive the Migration Health Agenda forward in Norway?

 

The growing body of migrant health research at all levels focuses around disease burden, risk factors/behaviours and on distal factors but research on policy issues remains limited. Internationally published declarations and recommendations to take the migrant health agenda forward address policy issues. However declarations at country are few and not systematically followed up.

The Bergen Declaration was endorsed at Norway's' First National Conference on Migration Health (2018) by the multi-disciplinary participants. The declaration reflects the ‘upstream' and ‘downstream' areas addressed and discussed at the conference and includes concrete recommendations for key areas. It was widely disseminated, including high-level policy makers. Prior to the second Migration Health Conference (2020), the progress of the recommendations were reviewed. Since 2018, Migrant Integration Policy Index (MIPEX) in Norway from 2015 was updated in 2019 and a Country Assessment as part of the WP7 of Joint Action on Health Equity Europe (JAHEE) was conducted providing the basis to review the recommendations of the Bergen Declaration. In addition, the 2020 Committee conducted a desk review and search to follow up the recommendations. The review revealed that among identified ‘upstream' areas most progress had been made with data collection and research and the least in policy and governance. Among the ‘downstream' areas some progress was observed regarding practise and access to health services. Education and Training had received some attention. The Bergen Declaration reflects the consensus regarding migrant health and recommendations to address these issues in Norway. Monitoring the progress made through data that included policy review revealed progress and gaps. Progress in research, education and practise was evident whereas policy change was not. Policy makers have not paid heed to the Bergen Declaration.

Key messages

The Bergen Declaration was a useful tool for initiating and monitoring progress in research, education and practice. Declarations do not support advancement of policies and other means are required to push the policies forward.

Cardiac output monitoring using transthoracic echocardiography in children after cardiac surgery-an observational study of feasibility and concordance with transpulmonary thermodilution

Background

Transthoracic echocardiography (TTE) is commonly used after pediatric cardiac surgery to monitor cardiac function and adequacy of surgery; however it depends on the availability of good echo window and operator skill [1]. Transpulmonary thermodilution (TPTD) is feasible along with calibrated continuous cardiac output measurement in children but seldom used due to cost and the need for a specialized catheter [2].

We hypothesized that TTE would be as good as TPTD, but limited in feasibility following pediatric cardiac surgery. Hence, the concordance, agreement as well as feasibility and trending of cardiac output monitoring by TTE was compared against a reference TPTD method in real-world usage in children after congenital heart surgery.

Methods

This was a secondary analysis of data from a previously registered and conducted study in our unit. TPTD monitoring was instituted in children undergoing congenital heart disease repair on cardiopulmonary bypass with a 3F femoral arterial cannula and a central venous injectate temperature sensor.

Cardiac output was also measured by transthoracic echocardiography by measurement of the left ventricular outflow tract (LVOT) diameter, LVOT velocity time integral (VTI) and the heart rate as previously described [3,4]. Measurements were taken after arrival in the ICU, and every 12 hours till after extubation. Correlation, Bland-Altman analysis and polar analysis was done for cardiac output measured by TPTD and TTE.

Results

TTE and TPTD measurements of cardiac output correlated well (Pearson's correlation coefficient 0.94; 95% CI 0.90–0.96) (Fig. 1A). Bland Altman analysis showed a mean bias of 0.15 l/min and upper and lower limits of agreement of 0.81 and −0.51 l/min respectively (Fig. 1B). Cardiac output measurement by TTE was possible in 72 instances while TPTD allowed measurement in all 113 instances. Hence, TTE was not feasible in 41 instances across 14 patients, including 19 instances in acyanotic and 22 instances in cyanotic patients. Polar analysis revealed acceptable trending.

Conclusions

TTE derived cardiac output demonstrated good correlation, minimal bias and narrow limits of agreement versus TPTD, and was feasible in most cases. This suggests TTE is an acceptable cardiac output measurement modality post pediatric cardiac surgery, as in adults [5]. TPTD-based continuous cardiac output monitoring might have a complementary role in pediatric cardiac critical care, particularly in high risk cases.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Institutional Special Research Grant from Postgraduate Institute of Medical Education and Research, Chandigarh, India. Figure 1