Prediction of hospital mortality among critically ill patients in a single centre in Asia: comparison of artificial neural networks and logistic regression-based model

INTRODUCTION

This study compared the performance of the artificial neural network (ANN) model with the Acute Physiologic and Chronic Health Evaluation (APACHE) II and IV models for predicting hospital mortality among critically ill patients in Hong Kong.

METHODS

This retrospective analysis included all patients admitted to the intensive care unit of Pamela Youde Nethersole Eastern Hospital from January 2010 to December 2019. The ANN model was constructed using parameters identical to the APACHE IV model. Discrimination performance was assessed using area under the receiver operating characteristic curve (AUROC); calibration performance was evaluated using the Brier score and Hosmer-Lemeshow statistic.

RESULTS

In total, 14 503 patients were included, with 10% in the validation set and 90% in the ANN model development set. The ANN model (AUROC=0.88, 95% confidence interval [CI]=0.86-0.90, Brier score=0.10; P in Hosmer-Lemeshow test=0.37) outperformed the APACHE II model (AUROC=0.85, 95% CI=0.80-0.85, Brier score=0.14; P<0.001 for both comparisons of AUROCs and Brier scores) but showed performance similar to the APACHE IV model (AUROC=0.87, 95% CI=0.85-0.89, Brier score=0.11; P=0.34 for comparison of AUROCs, and P=0.05 for comparison of Brier scores). The ANN model demonstrated better calibration than the APACHE II and APACHE IV models.

CONCLUSION

Our ANN model outperformed the APACHE II model but was similar to the APACHE IV model in terms of predicting hospital mortality in Hong Kong. Artificial neural networks are valuable tools that can enhance real-time prognostic prediction.

Yubi-Wakka Test for Sarcopenia Screening in the Community: Comparative Agreement, Diagnostic Performance and Validity with Calf Circumference Measurements

BACKGROUND

Screening tools such as calf circumference (CC) and Yubi-wakka (finger-ring) test have been recognized as effective tools by Asian Working Group for Sarcopenia 2019 (AWGS'19) for sarcopenia screening but their comparative agreement, diagnostic performance and validity are unclear.

OBJECTIVES

This study aims to determine: (i)agreement between calf and finger-ring circumference, (ii)diagnostic performance for low muscle mass and AWGS'19 sarcopenia diagnosis, (iii)correlation with muscle mass, strength, and physical performance, and (iv)association with frailty, life space mobility and physical activity.

METHODS

We studied 187 healthy community-dwelling older adults (mean age=66.8+7.0years) from the GERILABS-2 study. CC was measured via (i) both calves in sitting and standing positions, and (ii) Yubi-wakka test by encircling the thickest part of the non-dominant calf with index fingers and thumbs of both hands. We performed Cohen's kappa to check for agreement, area under receiver operating characteristic curve (AUC) to compare diagnostic performance, partial correlations adjusted for age and gender to compare convergent validity, and logistic regression to determine predictive validity for outcome measures.

RESULTS

Sarcopenia prevalence was 24.0% (AWGS'19). Yubi-wakka identified 16.6% of participants as screen-positive ("smaller"), showing moderate agreement only with non-dominant sitting CC measurements (k=0.421,p<0.001) and having lower diagnostic performance in determining low muscle mass (AUC=0.591 vs 0.855-0.870,p<0.001; sensitivity=57.1% vs 75.5-90.8%; specificity=58.4% vs 70.8-80.9%) and sarcopenia diagnosis (AUC=0.581 vs 0.788-0.818,p<0.001; sensitivity=55.6% vs 57.5-71.8%; specificity=74.4% vs 75.6-88.9%) compared to CC measurements. Yubi-wakka correlated significantly with muscle mass, grip strength and knee extension but not physical performance. When adjusted for age, gender and hypertension, Yubi-wakka was significantly associated with frailty (OR=3.96,95%CI:1.09-14.38), life space mobility (OR=2.38,95%CI:1.08-5.24) and physical activity (OR=2.50,95%CI:1.07-5.86).

DISCUSSION AND CONCLUSIONS

Yubi-wakka provides a self-administered, low-cost and practicable community screening tool for sarcopenia. Our study affirmed the convergent and predictive validity of Yubi-wakka, albeit with lower sensitivity and specificity in diagnostic performance compared to CC measurements.

EUFOREA summit in Brussels 2023: inspiring the future of allergy & respiratory care

In March 2023, the European Forum for Research and Education in Allergy and Airways diseases (EUFOREA) organized its bi-annual Summit in Brussels with expert panel members of EUFOREA, representatives of the EUFOREA patient advisory board, and the EUFOREA board and management teams. Its aim was to define the research, educational and advocacy initiatives to be developed by EUFOREA over the next 2 years until the 10th anniversary in 2025. EUFOREA is an international non-for-profit organization forming an alliance of all stakeholders dedicated to reducing the prevalence and burden of chronic allergic and respiratory diseases via research, education, and advocacy. Based on its medical scientific core competency, EUFOREA offers an evidence-supported platform to introduce innovation and education in healthcare leading to optimal patient care, bridging the gap between latest scientific evidence and daily practice. Aligned with the mission of improving health care, the expert panels of asthma, allergic rhinitis (AR), chronic rhinosinusitis (CRS) & European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS), allergen immunotherapy (AIT) and paediatrics have proposed and elaborated a variety of activities that correspond to major unmet needs in the allergy and respiratory field. The current report provides a concise overview of the achievements, ambitions, and action plan of EUFOREA for the future, allowing all stakeholders in the allergy and respiratory field to be up-dated and inspired to join forces in Europe and beyond.

Economic and environmental analysis of processing plant interventions to reduce fluid milk waste

With the increased awareness about the economic and environmental impact of food waste, many interventions along food supply chains have been proposed to mitigate food waste. Even though interventions used to target food waste usually revolve around logistics and operations management, we highlight a unique solution to address this issue, specifically for fluid milk. We target the intrinsic quality of fluid milk by evaluating interventions that will extend the product shelf life. We used data from a previous fluid milk spoilage simulation model, collected price and product information from retail stores, conducted an expert elicitation, and used hedonic price regressions to determine the private and social gains to the dairy processing plant when implementing 5 different interventions to extend shelf life. Our data suggest that the value of each additional day of shelf life is approximately $0.03 and indicate that increasing periodic equipment cleaning is the most cost-effective strategy for processing plants to achieve fluid milk shelf-life improvements, both from a firm's economic standpoint and from an environmental standpoint. Importantly, the approaches reported here will be valuable to help individual firms to generate customized facility and firm specific assessments that identify the most appropriate strategies for extending the shelf life of different dairy products.

Rhinitis associated with asthma is distinct from rhinitis alone: The ARIA-MeDALL hypothesis

Asthma, rhinitis and atopic dermatitis (AD) are interrelated clinical phenotypes that partly overlap in the human interactome. The concept of "one-airway-one-disease", coined over 20 years ago, is a simplistic approach of the links between upper- and lower-airway allergic diseases. With new data, it is time to reassess the concept. This article reviews (i) the clinical observations that led to Allergic Rhinitis and its Impact on Asthma (ARIA), (ii) new insights into polysensitisation and multimorbidity, (iii) advances in mHealth for novel phenotype definition, (iv) confirmation in canonical epidemiologic studies, (v) genomic findings, (vi) treatment approaches and (vii) novel concepts on the onset of rhinitis and multimorbidity. One recent concept, bringing together upper- and lower-airway allergic diseases with skin, gut and neuropsychiatric multimorbidities, is the "Epithelial Barrier Hypothesis". This review determined that the "one-airway-one-disease" concept does not always hold true and that several phenotypes of disease can be defined. These phenotypes include an extreme "allergic" (asthma) phenotype combining asthma, rhinitis and conjunctivitis. Rhinitis alone and rhinitis and asthma multimorbidity represent two distinct diseases with the following differences: (i) genomic and transcriptomic background (Toll-Like Receptors and IL-17 for rhinitis alone as a local disease; IL-33 and IL-5 for allergic and non-allergic multimorbidity as a systemic disease), (ii) allergen sensitisation patterns (mono- or pauci-sensitisation versus polysensitisation), (iii) severity of symptoms and (iv) treatment response. In conclusion, rhinitis alone (local disease) and rhinitis with asthma multimorbidity (systemic disease) should be considered as two distinct diseases, possibly modulated by the microbiome, and may be a model for understanding the epidemics of chronic and auto-immune diseases.

Hemolytic anemia following intravenous immunoglobulins in children with PIMS-TS: Two case reports

This is the first case report on two children presenting with immediate and severe hemolytic anemia following the administration of high-dose intravenous immunoglobulins (IVIGs) in the context of pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS). Hemolytic anemia was described as a significant decrease in hemoglobin and an increase in lactate dehydrogenase after the second administration of high-dose IVIGs was performed. Both patients were found to have AB blood group. One of our patients showed massive pallor, weakness, and inability to walk in association with hemolysis. However, in both cases, the anemia was self-limiting and transfusion of red blood cells was not required: both patients recovered without persistent impact. Nonetheless, we aim to draw attention to this widely unknown adverse effect of IVIG, especially in the context of PIMS-TS. We suggest determining the patient's blood group prior to high-dose IVIG infusion and replacing the second IVIG through high-dose steroids or anticytokine therapy. Using IVIGs containing lower titers of specifically anti-A or anti-B antibodies to avoid isoagglutinin-caused hemolytic anemia is desirable; however, the information is not routinely available.

Short-term risk prediction after major lower limb amputation: PERCEIVE study

BACKGROUND

The accuracy with which healthcare professionals (HCPs) and risk prediction tools predict outcomes after major lower limb amputation (MLLA) is uncertain. The aim of this study was to evaluate the accuracy of predicting short-term (30 days after MLLA) mortality, morbidity, and revisional surgery.

METHODS

The PERCEIVE (PrEdiction of Risk and Communication of outcomE following major lower limb amputation: a collaboratIVE) study was launched on 1 October 2020. It was an international multicentre study, including adults undergoing MLLA for complications of peripheral arterial disease and/or diabetes. Preoperative predictions of 30-day mortality, morbidity, and MLLA revision by surgeons and anaesthetists were recorded. Probabilities from relevant risk prediction tools were calculated. Evaluation of accuracy included measures of discrimination, calibration, and overall performance.

RESULTS

Some 537 patients were included. HCPs had acceptable discrimination in predicting mortality (931 predictions; C-statistic 0.758) and MLLA revision (565 predictions; C-statistic 0.756), but were poor at predicting morbidity (980 predictions; C-statistic 0.616). They overpredicted the risk of all outcomes. All except three risk prediction tools had worse discrimination than HCPs for predicting mortality (C-statistics 0.789, 0.774, and 0.773); two of these significantly overestimated the risk compared with HCPs. SORT version 2 (the only tool incorporating HCP predictions) demonstrated better calibration and overall performance (Brier score 0.082) than HCPs. Tools predicting morbidity and MLLA revision had poor discrimination (C-statistics 0.520 and 0.679).

CONCLUSION

Clinicians predicted mortality and MLLA revision well, but predicted morbidity poorly. They overestimated the risk of mortality, morbidity, and MLLA revision. Most short-term risk prediction tools had poorer discrimination or calibration than HCPs. The best method of predicting mortality was a statistical tool that incorporated HCP estimation.

Consumer perceptions of QR code technology for enhanced fluid milk shelf-life information provision in a retail setting

There is increasing awareness of the impact of food waste and the large role best-by or sell-by dates play in consumer food waste. To address this issue, predictive models have been developed that can not only provide more accurate best-by dates for fluid milk but could also be used to dynamically predict shelf-life (e.g., based on distribution data such as storage temperatures) and adjust prices for products closer to the end of shelf-life. However, limited information is available on strategies to communicate this type of information to consumers. Here we assessed the consumer acceptance of (1) quick response (QR) code technology to communicate product shelf-life and (2) shelf-life dependent pricing based on QR codes by offering both half-gallon fluid milk with traditional printed best-by dates and identical products with QR codes to convey best-by dates over an 8-wk time period in a retail setting. Overall, 62% of half-gallon containers sold over this time frame featured QR codes and 48% of QR code scans were linked to subsequent sales, suggesting the possibility of substantial consumer acceptance of novel technologies to display and communicate best-by dates. Preliminary data based on a small number of sales also showed that consumers did purchase QR code-labeled products offered at a reduced price due to limited remaining shelf-life. Our data suggest that at least some consumer segments would adopt QR code-based shelf-life labels, which presents an opportunity to better manage and communicate "best-by" dates and use dynamic pricing strategies to reduce food waste that occurs when an end-of-shelf-life product is either not sold or is discarded by consumers. Overall, QR codes represent a strategic opportunity for the dairy industry to achieve greater sustainability and to foster stronger connections with customers through enhanced provision of information that highlights sustainability practices implemented across the whole supply chain.

Differential sensitivity of assays for determining vein endothelial cell senescence

In vivo endothelialization of polymer-based cardiovascular implant materials is a promising strategy to reduce the risk of platelet adherence and the subsequent thrombus formation and implant failure. However, endothelial cells from elderly patients are likely to exhibit a senescent phenotype that may counteract endothelialization. The senescence status of cells should therefore be investigated prior to implantation of devices designed to be integrated in the blood vessel wall. Here, human umbilical vein endothelial cells (HUVEC) were cultivated up to passage (P) 4, 10 and 26/27 to determine the population doubling time and the senescence status by four different methods. Determination of the senescence-associated β-galactosidase activity (SA-β-Gal) was carried out by colorimetric staining and microscopy (i), as well as by photometric quantification (ii), and the expression of senescence-associated nuclear proteins p16 and p21 as well as the proliferation marker Ki67 was assessed by immunostaining (iii), and by flow cytometry (iv). The population doubling time of P27-cells was remarkably greater (103±65 h) compared to P4-cells (24±3 h) and P10-cell (37±15 h). Among the four different methods tested, the photometric SA-β-Gal activity assay and the flow cytometric determination of p16 and Ki67 were most effective in discriminating P27-cells from P4- and P10-cells. These methods combined with functional endothelial cell analyses might aid predictions on the performance of implant endothelialization in vivo.

Development of a Monte Carlo simulation model to predict pasteurized fluid milk spoilage due to post-pasteurization contamination with gram-negative bacteria

Psychrotolerant gram-negative bacteria introduced as post-pasteurization contamination (PPC) are a major cause of spoilage and reduced shelf life of high-temperature, short-time pasteurized fluid milk. To provide improved tools to (1) predict pasteurized fluid milk shelf life as influenced by PPC and (2) assess the effectiveness of different potential interventions that could reduce spoilage due to PPC, we developed a Monte Carlo simulation model that predicts fluid milk spoilage due to psychrotolerant gram-negative bacteria introduced as PPC. As a first step, 17 gram-negative bacterial isolates frequently associated with fluid milk spoilage were selected and used to generate growth data in skim milk broth at 6°C. The resulting growth parameters, frequency of isolation for the 17 different isolates, and initial concentration of bacteria in milk with PPC, were used to develop a Monte Carlo model to predict bacterial number at different days of shelf life based on storage temperature of milk. This model was then validated with data from d 7 and 10 of shelf life, collected from commercial operations. The validated model predicted that the parameters (1) maximum growth rate and (2) storage temperature had the greatest influence on the percentage of containers exceeding 20,000 cfu/mL standard plate count on d 7 and 10 (i.e., spoiling due to PPC), which indicates that accurate data on maximum growth rate and storage temperature are important for accurate predictions. In addition to allowing for prediction of fluid milk shelf life, the model allows for simulation of "what-if" scenarios, which allowed us to predict the effectiveness of different interventions to reduce overall fluid milk spoilage due to PPC through a set of proof-of-concept scenario (e.g., frequency of PPC in containers reduced from 100% to 10%; limiting distribution temperature to a maximum of 6°C). Combined with other models, such as previous models on fluid milk spoilage due to psychrotolerant spore-forming bacteria, the data and tools developed here will allow for rational, digitally enabled, fluid milk shelf life prediction and quality enhancement.

1529 Management of A Rare Case of Bilateral Persistent Sciatic Artery Aneurysms Causing Critical Limb Ischaemia With Staged Embolisation And Femoropopliteal Bypass: A Case Report

Introduction

Bilateral persistent sciatic arteries (PSA) are rare with an incidence of 0.001%. They represent a persistence of the embryonic axial limb circulation via the internal iliac artery. Normally the PSA involutes and is replaced by the superficial femoral artery (SFA). Failure of regression leads to a PSA with varying configurations. Up to 50% of PSAs are aneurysmal and may present with rupture or acute/chronic ischaemia, typically at 40-50 years old.

Case Report

A 74-year-old female presented with limb threatening ischaemia manifesting with rest pain, sensory deficit and early tissue loss (Rutherford IIb). She had a left femoral pulse but absent pulses distally. Pedal pulses were noted on the contralateral limb. CT angiogram revealed bilateral complete PSAs with incomplete hypoplastic SFAs (Pillet-Gauffre 2a). Both PSAs were aneurysmal; the left PSA was acutely occluded distal to the aneurysm. She underwent staged intervention with percutaneous embolisation of the left PSA, followed by femoropopliteal bypass. She was discharged six days later with good symptomatic relief at one month follow up. We are planning to treat the contralateral limb in a similar manner electively in case complications occur.

Conclusions

PSAs are commonly associated with limb threatening complications but due to their rarity there are limited reports on the management of this condition. Here we can report a good outcome in a late presentation using staged embolisation with open reconstruction.

P–016 Using artificial intelligence to predict semen upgrading after microsurgical varicocele repair

Study question

Can we use artificial intelligence models to predict semen upgrading after microsurgical varicocele repair?

Summary answer

A machine learning model performed well in predicting clinically meaningful post-varicocelectomy semen upgrade using pre-operative hormonal, clinical, and semen analysis data.

What is known already

Varicocele repair is recommended in the presence of a clinical varicocele together with at least one abnormal semen parameter, and male infertility. Unfortunately, up to 50% of men who meet criteria for repair will not see meaningful benefit in outcomes despite successful surgery. Nomograms exist to help predict success, but these are based out of single-center databases, do not incorporate hormonal data, and are rarely designed to predict pre-defined, clinically meaningful improvements in semen parameters.

Study design, size, duration

Data were collected from an international, multi-center retrospective cohort. A total of 240 men were identified. Data from 160 men from Miami, USA and 80 men from Toronto, Canada were included. Data was collected from 2006 to 2020.

Participants/materials, setting, methods

We collected pre and postoperative clinical data following varicocele surgery. Clinical upgrading was defined as an increase in sperm concentration that would allow a couple to access new reproductive technologies/techniques. The tiers used for upgrading were 0–1million/cc (Intracytoplasmic Sperm Injection), 1–5 million (In Vitro Fertilization), 5–15 million (Intrauterine Insemination), and &gt;15 million (Natural conception). Artificial intelligence models were trained and tested using R to predict which patients upgraded after surgery.

Main results and the role of chance

51% of men underwent bilateral varicocele repair. The majority of men had grade 2 varicocele on the left, and (when present) a grade 1 varicocele on the right. Overall, 47% of men experienced an upgrade following varicocele surgery, 47% did not change, and 6% downgraded. The data from Miami were used to create a random forest model for predicting clinically significant upgrade in sperm concentration. The most informative model parameters were preoperative FSH, sperm concentration, and surgical laterality. The model identified three clinical categories: men with unfavorable, intermediate, and favorable features to predict varicocele upgrade. On external validation using data from Toronto, the model accurately predicted upgrade in 87% of men with favorable features, and in 49% and 36% of men with intermediate and unfavorable features, respectively. Overall, the model performed well on external validation with an AUC of 0.72 and good calibration.

Calibration plots, using cross-validation, define how well the predicted probabilities match the actual probability of sperm concentration upgrade. The random forest model was run twelve times. All model characteristics are the mean of ten model runs with the highest and lowest performing runs removed.

The model was translated to an online calculator that can be used by clinicians.

Limitations, reasons for caution

One limitation to our study is that we were not able to predict total motile sperm count (TMSC), which has been shown to perform slightly better than concentration at predicting assisted reproduction outcomes. By focusing on clinically significant upgrading, this difference should be minimized.

Wider implications of the findings: Predicting the chances of clinically significant semen upgrading after varicocele repair is essential for patients and clinicians to understand. Several men undergo surgery with no subsequent benefit, which may lead to a delay in definitive treatment with IVF/IUI. Understanding their chances will help couples make better informed decisions moving forward.

Trial registration number

Not applicable

The influence of different rewetting procedures on the thrombogenicity of nanoporous poly(ether imide) microparticles

Nanoporous microparticles prepared from poly(ether imide) (PEI) are discussed as candidate adsorber materials for the removal of uremic toxins during apheresis. Polymers exhibiting such porosity can induce the formation of micro-gas/air pockets when exposed to fluids. Such air presenting material surfaces are reported to induce platelet activation and thrombus formation. Physical or chemical treatments prior to implantation are discussed to reduce the formation of such gas nuclei. Here, we report about the influence of different rewetting procedures - as chemical treatments with solvents - on the thrombogenicity of hydrophobic PEI microparticles and PEI microparticles hydrophilized by covalent attachment of poly(vinyl pyrrolidone) (PVP) of two different chain lengths.Autoclaved dry PEI particles of all types with a diameter range of 200 - 250 μm and a porosity of about 84% ±2% were either rewetted directly with phosphate buffered saline (24 h) or after immersion in an ethanol-series. Thrombogenicity of the particles was studied in vitro upon contact with human sodium citrated whole blood for 60 min at 5 rpm vertical rotation. Numbers of non-adherent platelets were quantified, and adhesion of blood cells was qualitatively analyzed by bright field microscopy. Platelet activation (percentage of CD62P positive platelets and amounts of soluble P-Selectin) and platelet function (PFA100 closure times) were analysed.Retention of blood platelets on the particles was similar for all particle types and both rewetting procedures. Non-adherent platelets were less activated after contact with ethanol-treated particles of all types compared to those rewetted with phosphate buffered saline as assessed by a reduced number of CD62P-positive platelets and reduced amounts of secreted P-Selectin (P < 0.05 each). Interestingly, the hydrophilic surfaces significantly increased the number of activated platelets compared to hydrophobic PEI regardless of the rewetting agent. This suggests that, apart from wettability, other material properties might be more important to regulate platelet activation. PFA100 closure times were reduced and within the reference ranges in the ethanol group, however, significantly increased in the saline group. No substantial difference was detected between the tested surface modifications. In summary, rewetting with ethanol resulted in a reduced thrombogenicity of all studied microparticles regardless of their wettability, most likely resulting from the evacuation of air from the nanoporous particles.

Transanal mesorectal excision: early outcomes in Australia and New Zealand

BACKGROUND

Transanal total mesorectal excision (taTME) aims to overcome some of the technical challenges faced when operating on mid and low rectal cancers. Specimen quality has been confirmed previously, but recent concerns have been raised about oncological safety. This multicentre prospective study aimed to evaluate the safety of taTME among early adopters in Australia and New Zealand.

METHODS

Data from all consecutive patients who had taTME for rectal cancer from July 2014 to February 2020 at six tertiary referral centres in Australasia were recorded and analysed.

RESULTS

A total of 308 patients of median age of 64 years underwent taTME. Some 75.6 per cent of patients were men, and the median BMI was 26.8 kg/m2. The median distance of tumour from anal verge was 7 cm. Neoadjuvant chemoradiotherapy was administered to 57.8 per cent of patients. The anastomotic leak rate was 8.1 per cent and there was no mortality within 30 days of surgery. Pathological examination found a complete mesorectum in 295 patients (95.8 per cent), a near-complete mesorectum in seven patients (2.3 per cent), and an incomplete mesorectum in six patients (1.9 per cent). The circumferential resection margin and distal resection margin was involved in nine patients (2.9 per cent), and two patients (0.6 per cent) respectively. Over a median follow-up of 22 months, the local recurrence rate was 1.9 per cent and median time to local recurrence was 30.5 months.

CONCLUSION

This study showed that, with appropriate training and supervision, skilled minimally invasive rectal cancer surgeons can perform taTME with similar pathological and oncological results to open and laparoscopic surgery.