Quantification of water exchange across the blood-brain barrier using noncontrast MR fingerprinting.

PURPOSE: A method is proposed to quantify cerebral blood volume ( v b $$ {v}_b $$ ) and intravascular water residence time ( τ b $$ {\tau}_b $$ ) using MR fingerprinting (MRF), applied using a spoiled gradient echo sequence without the need for contrast agent. METHODS: An in silico study optimized an acquisition protocol to maximize the sensitivity of the measurement to v b $$ {v}_b $$ and τ b $$ {\tau}_b $$ changes. Its accuracy in the presence of variations in T 1 , t $$ {\mathrm{T}}_{1,t} $$ , T 1 , b $$ {\mathrm{T}}_{1,b} $$ , and B 1 $$ {\mathrm{B}}_1 $$ was evaluated. The optimized protocol (scan time of 19 min) was then tested in a exploratory healthy volunteer study (10 volunteers, mean age 24 ± $$ \pm $$ 3, six males) at 3 T with a repeat scan taken after repositioning to allow estimation of repeatability. RESULTS: Simulations show that assuming literature values for T 1 , b $$ {\mathrm{T}}_{1,b} $$ and T 1 , t $$ {\mathrm{T}}_{1,t} $$ , no variation in B 1 $$ {\mathrm{B}}_1 $$ , while fitting only v b $$ {v}_b $$ and τ b $$ {\tau}_b $$ , leads to large errors in quantification of v b $$ {v}_b $$ and τ b $$ {\tau}_b $$ , regardless of noise levels. However, simulations also show that matching T 1 , t $$ {\mathrm{T}}_{1,t} $$ , T 1 , b $$ {\mathrm{T}}_{1,b} $$ , B 1 + $$ {\mathrm{B}}_1^{+} $$ , v b $$ {v}_b $$ and τ b $$ {\tau}_b $$ , simultaneously is feasible at clinically achievable noise levels. Across the healthy volunteers, all parameter quantifications fell within the expected literature range. In addition, the maps show good agreement between hemispheres suggesting physiologically relevant information is being extracted. Expected differences between white and gray matter T 1 , t $$ {\mathrm{T}}_{1,t} $$ (p < 0.0001) and v b $$ {v}_b $$ (p < 0.0001) are observed, T 1 , b $$ {\mathrm{T}}_{1,b} $$ and τ b $$ {\tau}_b $$ show no significant differences, p = 0.4 and p = 0.6, respectively. Moderate to excellent repeatability was seen between repeat scans: mean intra-class correlation coefficient of T 1 , t : 0 . 91 $$ {\mathrm{T}}_{1,t}:0.91 $$ , T 1 , b : 0 . 58 $$ {\mathrm{T}}_{1,b}:0.58 $$ , v b : 0 . 90 $$ {v}_b:0.90 $$ , and τ b : 0 . 96 $$ {\tau}_b:0.96 $$ . CONCLUSION: We demonstrate that regional simultaneous quantification of v b $$ {v}_b $$ , τ b $$ {\tau}_b $$ , T 1 , b , T 1 , t $$ {\mathrm{T}}_{1,b},{T}_{1,t} $$ , and B 1 + $$ {\mathrm{B}}_1^{+} $$ using MRF is feasible in vivo.

Prehospital Ground and Helicopter-Based Extracorporeal Cardiopulmonary Resuscitation (ECPR) Reduce Barriers to ECPR: A GIS Model.

INTRODUCTION: Evidence suggests that Extracorporeal Cardiopulmonary Resuscitation (ECPR) can improve survival rates for nontraumatic out-of-hospital cardiac arrest (OHCA). However, when ECPR is indicated over 50% of potential candidates are unable to qualify in the current hospital-based system due to geographic limitations. This study employs a Geographic Information System (GIS) model to estimate the number of ECPR eligible patients within the United States in the current hospital-based system, a prehospital ECPR ground-based system, and a prehospital ECPR Helicopter Emergency Medical Services (HEMS)-based system. METHODS: We constructed a GIS model to estimate ground and helicopter transport times. Time-dependent rates of ECPR eligibility were derived from the Resuscitation Outcome Consortium (ROC) database, while the Cardiac Arrest Registry to Enhance Survival (CARES) registry determined the number of OHCA patients meeting ECPR criteria within designated transportation times. Emergency Medical Services (EMS) response time, ECPR candidacy determination time, and on-scene time were modeled based on data from the EROCA trial. The combined model was used to estimate the total ECPR eligibility in each system. RESULTS: The CARES registry recorded 736,066 OHCA patients from 2013 to 2021. After applying clinical criteria, 24,661 (3.4%) ECPR-indicated OHCA were identified. When considering overall ECPR eligibility within 45 minutes from OHCA to initiation, only 11.76% of OHCA where ECPR was indicated were eligible in the current hospital-based system. The prehospital ECPR HEMS-based system exhibited a four-fold increase in ECPR eligibility (49.3%), while the prehospital ground-based system showed a more than two-fold increase (28.4%). CONCLUSIONS: The study demonstrates a two-fold increase in ECPR eligibility for a field-deployable ground-based system and a four-fold increase for a prehospital ECPR HEMS-based system compared to the current hospital-based OHCA system. This novel GIS model can inform future ECPR implementation strategies, optimizing systems of care.

High prevalence of diabetes among young First Nations Peoples with metabolic dysfunction-associated steatotic liver disease: a population-based study in Australia.

BACKGROUND: Liver disease is an important contributor to the mortality gap between First Nations Peoples and non-Indigenous Australian adults. Despite a high burden of metabolic comorbidities among First Nations Peoples, data about the epidemiology of metabolic dysfunction-associated steatotic liver disease (MASLD) in this population is scarce. METHODS: A retrospective analysis of all adults hospitalized with MASLD or metabolic dysfunction-associated steatohepatitis (MASH) with/without cirrhosis during 2007-2019 in the state of Queensland was performed. Patients were followed from the first admission with MASLD/MASH (identified based on validated algorithms) to decompensated cirrhosis and overall mortality. We explored differences according to Indigenous status using Multivariable Cox regression. FINDINGS: 439 First Nations Peoples and 7,547 non-Indigenous Australians were followed for a median of 4.6 years (interquartile range 2.7-7.2). Overall, women were overrepresented, but more so in the First Nations cohort (72.7% vs. 57.0%, p < 0.001). First Nations patients were younger, a higher proportion lived in remote and socioeconomic disadvantaged areas, and had higher comorbidity compared to non-Indigenous Australians (all p < 0.001). Diabetes, the most common comorbidity affecting both groups, was overrepresented in First Nations Peoples versus non-Indigenous Australians (43.5% vs. 30.8%, p < 0.001, respectively). Nineteen (4.3%) First Nations Peoples and 332 (4.4%) of non-Indigenous patients progressed to cirrhosis decompensation (9.0% [95%CI 4.5-17.7] vs. 7.7% [95%CI 6.6-8.9; p = 0.956] respectively within 10 years). In multivariable analysis, there was no association between Indigenous status and progression to decompensated cirrhosis (p = 0.759) and survival (p = 0.437). CONCLUSIONS: This study provides the first population-based epidemiological data on MASLD in First Nations Australians. The high prevalence of diabetes (that is associated with advanced fibrosis and liver disease mortality) among young First Nations Peoples with MASLD raises concern about future risk of progressive liver disease in this patient population. These data highlight the importance of early identification of MASLD, and providing culturally appropriate intervention to reduce disease progression in parallel with the management of cardiometabolic comorbidities.

Triage of V-V ECMO referrals for COVID-19 respiratory failure.

BACKGROUND: As the pandemic progressed, the use of extracorporeal membrane oxygenation (ECMO) for COVID-19-related acute respiratory distress syndrome increased, and patient triage and transfer to ECMO centers became important to optimize patient outcomes. Our objectives are to identify predictors of patient transfer for veno-venous extracorporeal membrane oxygenation (V-V ECMO) evaluation as well as to describe the outcomes of accepted patients. METHODS: This is a single-center, retrospective analysis of V-V ECMO transfer requests for adult patients with known or suspected COVID-19 and respiratory failure from March 2020 until March 2021. Data were collected prospectively during the triage process for transfer requests as part of clinical patient care at our institution. RESULTS: Of 341 referred patients, 112 (33%) were accepted for transfer to our facility, whereas 229 (67%) patients were declined for transfer. The Classification and Regression Tree analysis showed that patients' high pressure during airway pressure release ventilation (APRV) and age were the variables most significantly associated with the decision to accept or decline patients for transfer. CONCLUSIONS: Our triage process enabled one-third of referred patients to be transferred for evaluation, with nearly 70% of those patients ultimately receiving ECMO support. High ventilator settings on APRV and young age were associated with acceptance for transfer. Accepted patients also had a higher incidence of adjunctive therapies (proning and paralysis) prior to transfer request, less cardiac or renal dysfunction, and a shorter duration of mechanical ventilation. Further research is warranted to investigate the outcomes of nontransferred patients.

Derivation of a Procedural Performance Checklist for Bifemoral Veno-Venous Extracorporeal Membrane Oxygenation Cannula Placement in Operational Environments.

BACKGROUND: Veno-venous extracorporeal membrane oxygenation (VV ECMO) is a low-frequency, high-intensity procedure used for severe lung illness or injury to facilitate rapid correction of hypoxemia and respiratory acidosis. This technology is more portable and extracorporeal support is more frequently performed outside of the hospital. Future conflicts may require prolonged causality care and more specialized critical care capabilities including VV ECMO to improve patient outcomes. We used an expert consensus survey based on a developed bifemoral VV ECMO cannulation checklist with an operational focus to establish a standard for training, validation testing, and sustainment. METHODS: A 36-item procedural checklist was provided to 14 experts from multiple specialties. Using the modified Delphi method, the checklist was serially modified based on expert feedback. RESULTS: Three rounds of the study were performed, resulting in a final 32-item checklist. Each item on the checklist received at least 70% expert agreement on its inclusion in the final checklist. CONCLUSION: A procedural performance checklist was created for bifemoral VV ECMO using the modified Delphi method. This is an objective tool to assist procedural training and validation for medical providers performing VV ECMO in austere environments.

Cannula associated deep vein thromboses in COVID-19 patients supported with VV ECMO.

BACKGROUND: VV ECMO is increasingly used as a rescue strategy for hypercarbic and hypoxic respiratory failure refractory to conventional management, and more than 14,000 patients with COVID-19 related respiratory failure have been supported with VV ECMO to date. One of the known complications of VV ECMO support is the development of cannula-associated deep vein thromboses (CaDVT). The purpose of this study was to identify the incidence of CaDVT in COVID-19 patients supported with VV ECMO as compared to non-COVID-19 patients. We hypothesized that due to the hypercoagulable state and longer duration of VV ECMO support required for patients with COVID-19, a higher incidence of CaDVT would be observed in these patients. METHODS: This is a single center, retrospective observational study. About 291 non-trauma adult patients who were cannulated for VV ECMO and managed at our institution from January 1, 2014 to January 10, 2022 were included. The primary outcome was the presence of CaDVT 24 h after decannulation in COVID-19 versus non-COVID-19 patients. Our secondary outcome was continued presence of DVT on follow up imaging. CaDVT were defined as venous thrombi detected at prior cannulation sites. RESULTS: Both groups had a high incidence of CaDVT. There was no significant difference in the incidence of CaDVT in COVID-19 patients compared to non-COVID-19 patients (95% vs 88%, p = 0.13). Patients with COVID-19 had an increased incidence of persistent CaDVT on repeat imaging (78% vs 56%, p = 0.03). CONCLUSION: Given the high number of post-decannulation CaDVT in both groups, routine screening should be a part of post ECMO care in both populations. Repeat venous duplex ultrasound should be performed to assess for the need for ongoing treatment given the high incidence of CaDVT that persisted on repeat duplex scans.

A Cost Model for a Low-Threshold Clinic Treating Opioid Use Disorder.

The US fee-for-service payment system under-reimburses clinics offering access to comprehensive treatments for opioid use disorder (OUD). The funding shortfall limits a clinic's ability to expand and improve access, especially for socially marginalized patients with OUD. New payment models, however, should reflect the high variation in cost for using a clinic's clinical and voluntary psychosocial and recovery support services. The authors applied time-driven activity-based costing, a patient-level, micro-costing approach, to estimate the cost at an outpatient clinic that delivers medication for opiate used disorder (MOUD) and voluntary psychosocial and recovery support services. Much of the cost variation could be explained by classifying patients into three archetypes: (1) light touch (1-3 visits): no significant co-occurring psychiatric illness, stable housing, and easy to connect for ongoing OUD treatment in a traditional outpatient setting; (2) standard (average of 8 visits): initially requires an integrated team-based care model but soon stabilizes for transition to community-based outpatient care; (3) quad morbidity (> 20 visits): multiple co-occurring substance use disorders, unhoused, co-occurring medical and psychiatric complexity, and limited social supports. With the cost of the initial visit set at an indexed value of 100, an average light touch patient had a cost of 352, a standard patient was 718, and a quad morbidity patient was 1701. The cost structure revealed by this analysis provides the foundation for alternative payment models that would enable new MOUD clinics, staffed with multi-disciplinary care teams, and located for convenient access by high-risk patients, to be established and sustained.

Venovenous extracorporeal membrane oxygenation in patients with traumatic brain injuries and severe respiratory failure: A single-center retrospective analysis.

BACKGROUND: Venovenous extracorporeal membrane oxygenation (VV ECMO) can support trauma patients with severe respiratory failure. Use in traumatic brain injury (TBI) may raise concerns of worsening complications from intracranial bleeding. However, VV ECMO can rapidly correct hypoxemia and hypercarbia, possibly preventing secondary brain injury. We hypothesize that adult trauma patients with TBI on VV ECMO have comparable survival with trauma patients without TBI. METHODS: A single-center, retrospective cohort study involving review of electronic medical records of trauma admissions between July 1, 2014, and August 30, 2022, with discharge diagnosis of TBI who were placed on VV ECMO during their hospital course was performed. RESULTS: Seventy-five trauma patients were treated with VV ECMO; 36 (48%) had TBI. Of those with TBI, 19 (53%) had a hemorrhagic component. Survival was similar between patients with and without a TBI (72% vs. 64%, p = 0.45). Traumatic brain injury survivors had a higher admission Glasgow Coma Scale (7 vs. 3, p < 0.001) than nonsurvivors. Evaluation of prognostic scoring systems on initial head computed tomography demonstrated that TBI VV ECMO survivors were more likely to have a Rotterdam score of 2 (62% vs. 20%, p = 0.03) and no survivors had a Marshall score of ≥4. Twenty-nine patients (81%) had a repeat head computed tomography on VV ECMO with one incidence of expanding hematoma and one new focus of bleeding. Neither patient with a new/worsening bleed received anticoagulation. Survivors demonstrated favorable neurologic outcomes at discharge and outpatient follow-up, based on their mean Rancho Los Amigos Scale (6.5; SD, 1.2), median Cerebral Performance Category (2; interquartile range, 1-2), and median Glasgow Outcome Scale-Extended (7.5; interquartile range, 7-8). CONCLUSION: In this series, the majority of TBI patients survived and had good neurologic outcomes despite a low admission Glasgow Coma Scale. Venovenous extracorporeal membrane oxygenation may minimize secondary brain injury and may be considered in select patients with TBI. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level IV.

Gene Variants Implicated in Steatotic Liver Disease: Opportunities for Diagnostics and Therapeutics.

Non-alcoholic fatty liver disease (NAFLD) describes a steatotic (or fatty) liver occurring as a consequence of a combination of metabolic, environmental, and genetic factors, in the absence of significant alcohol consumption and other liver diseases. NAFLD is a spectrum of conditions. Steatosis in the absence of inflammation is relatively benign, but the disease can progress into more severe forms like non-alcoholic steatohepatitis (NASH), liver cirrhosis, and hepatocellular carcinoma. NAFLD onset and progression are complex, as it is affected by many risk factors. The interaction between genetic predisposition and other factors partially explains the large variability of NAFLD phenotype and natural history. Numerous genes and variants have been identified through large-scale genome-wide association studies (GWAS) that are associated with NAFLD and one or more subtypes of the disease. Among them, the largest effect size and most consistent association have been patatin-like phospholipase domain-containing protein 3 (PNPLA3), transmembrane 6 superfamily member 2 (TM6SF2), and membrane-bound O-acyltransferase domain containing 7 (MBOAT7) genes. Extensive in vitro and in vivo studies have been conducted on these variants to validate these associations. The focus of this review is to highlight the genetics underpinning the molecular mechanisms driving the onset and progression of NAFLD and how they could potentially be used to improve genetic-based diagnostic testing of the disease and develop personalized, targeted therapeutics.

Changing Prevalence of Medication Use in People with Cirrhosis: A Retrospective Cohort Study Using Pharmaceutical Benefits Scheme Data.

BACKGROUND: Safe and appropriate use of medicines is essential to improve health outcomes in cirrhosis. However, little is known about the number and type of medicines dispensed to people with cirrhosis in Australia, as this predominantly occurs in the community. We aimed to characterise the prescriptions dispensed to people with cirrhosis and explore changes in the use of medication groups over time. METHODS: Pharmaceutical Benefits Scheme data between 1 January 2016 and 30 June 2020 was extracted for consenting CirCare participants (multi-site, prospective, observational study). Prescriptions dispensed from cirrhosis diagnosis until liver transplant or death were included. Safety classifications for dispensed medicines were defined using published evidence-based recommendations. The pattern of medication use was analysed in 6-monthly time intervals. Generalised estimating equations models were used to estimate the change in consumption of medicines over time. RESULTS: Five hundred twenty-two patients (mean age 60 years, 70% male, 34% decompensated at recruitment) were dispensed 89,615 prescriptions during the follow-up period, representing a median of 136 [interquartile range (IQR) 62-237] prescriptions and a median of 16 (IQR 11-23) unique medicines per patient (total n = 9306 medicines). The most commonly used medicines were proton pump inhibitors (PPIs) (dispensed at least once to 73% of patients), opioids (68%) and antibiotics (89%). Polypharmacy was prevalent, with 59-69% of observed participants in each time period dispensed five or more unique medicines. Prescription medication use increased over time (p < 0.001) independently of age, comorbidity burden and liver disease aetiology. The likelihood of taking PPIs, opioids, antidepressants and inhaled medicines also increased with each successive time period. Use of angiotensin therapies, metformin and statins differed over time between patients with compensated versus decompensated cirrhosis. General practitioners prescribed 69% of dispensed medicines, including a higher proportion of 'unsafe' and 'safety unknown' medicines compared with consultants/specialists (p < 0.001). CONCLUSIONS: Polypharmacy is common in people with cirrhosis and some medication groups may be overused. Pharmacovigilance is required and future medication safety efforts should target high-risk prescribing practices and promote medication rationalisation in the community.

Radiographic pneumonia in young febrile infants presenting to the emergency department: secondary analysis of a prospective cohort study.

OBJECTIVE: The lack of evidence-based criteria to guide chest radiograph (CXR) use in young febrile infants results in variation in its use with resultant suboptimal quality of care. We sought to describe the features associated with radiographic pneumonias in young febrile infants. STUDY DESIGN: Secondary analysis of a prospective cohort study in 18 emergency departments (EDs) in the Pediatric Emergency Care Applied Research Network from 2016 to 2019. Febrile (≥38°C) infants aged ≤60 days who received CXRs were included. CXR reports were categorised as 'no', 'possible' or 'definite' pneumonia. We compared demographics, clinical signs and laboratory tests among infants with and without pneumonias. RESULTS: Of 2612 infants, 568 (21.7%) had CXRs performed; 19 (3.3%) had definite and 34 (6%) had possible pneumonias. Patients with definite (4/19, 21.1%) or possible (11/34, 32.4%) pneumonias more frequently presented with respiratory distress compared with those without (77/515, 15.0%) pneumonias (adjusted OR 2.17; 95% CI 1.04 to 4.51). There were no differences in temperature or HR in infants with and without radiographic pneumonias. The median serum procalcitonin (PCT) level was higher in the definite (0.7 ng/mL (IQR 0.1, 1.5)) vs no pneumonia (0.1 ng/mL (IQR 0.1, 0.3)) groups, as was the median absolute neutrophil count (ANC) (definite, 5.8 K/mcL (IQR 3.9, 6.9) vs no pneumonia, 3.1 K/mcL (IQR 1.9, 5.3)). No infants with pneumonia had bacteraemia. Viral detection was frequent (no pneumonia (309/422, 73.2%), definite pneumonia (11/16, 68.8%), possible pneumonia (25/29, 86.2%)). Respiratory syncytial virus was the predominant pathogen in the pneumonia groups and rhinovirus in infants without pneumonias. CONCLUSIONS: Radiographic pneumonias were uncommon in febrile infants. Viral detection was common. Pneumonia was associated with respiratory distress, but few other factors. Although ANC and PCT levels were elevated in infants with definite pneumonias, further work is necessary to evaluate the role of blood biomarkers in infant pneumonias.

Diabetes mellitus and the progression of non-alcoholic fatty liver disease to decompensated cirrhosis: a retrospective cohort study.

OBJECTIVE: To determine the incidence of decompensated cirrhosis and associated risk factors in people hospitalised with non-alcoholic fatty liver disease (NAFLD) or non-alcoholic steatohepatitis (NASH) with or without cirrhosis. DESIGN: Retrospective cohort study; analysis of linked Queensland Hospital Admitted Patient Data Collection, Queensland Registry of Births, Deaths and Marriages, and Queensland Cancer Register data. SETTING, PARTICIPANTS: Queensland residents aged 20 years or older admitted to Queensland hospitals with NAFLD/NASH during 1 July 2009 - 31 December 2018. MAIN OUTCOME MEASURES: Progression to decompensated cirrhosis (ascites, hepatic encephalopathy, or oesophageal variceal bleeding). RESULTS: We included data for 8006 patients in our analysis (10 082 admissions), including 4632 women (58%) and 2514 people with diabetes mellitus (31%); median follow-up time was 4.6 years (interquartile range, 2.7-7.2 years). Three hundred and fifty-one people (4.4%) experienced decompensated cirrhosis during the follow-up period. Of the 6900 people without cirrhosis, 4.5% (95% confidence interval [CI], 3.6-5.7%) experienced decompensated cirrhosis within ten years (mean, 0.5% per year; 95% CI, 0.4-0.6% per year); risk of progression was greater for people aged 70 years or older (v 20-39 years: adjusted hazard ratio [aHR], 4.7; 95% CI, 2.0-11.0) and those who had extrahepatic cancers (aHR, 5.0; 95% CI, 3.0-8.2), history of major cardiovascular events (aHR, 1.9; 95% CI, 1.2-3.1), or diabetes mellitus (aHR, 2.8; 95% CI, 2.0-3.9). Of the 1106 people with cirrhosis, 32.4% (95% CI, 27.2-38.3%) experienced decompensated cirrhosis within ten years (mean, 5.5% per year; 95% CI, 4.8-6.3% per year); risk of progression was greater for those with portal hypertension (aHR, 1.8; 95% CI, 1.3-2.7), extrahepatic cancer (aHR, 1.8; 95% CI, 1.1-2.9), or diabetes mellitus (aHR, 1.5; 95% CI, 1.1-2.0). Compared with people who had neither cirrhosis nor diabetes mellitus, the risk of decompensation was greater for people with cirrhosis (aHR, 10.7; 95% CI, 7.6-15.0) or cirrhosis and diabetes mellitus (aHR, 14.4; 95% CI, 10.1-20.6). CONCLUSIONS: Given the greater risk of progression to cirrhosis decompensation in people with diabetes mellitus, a disorder common in people with NAFLD/NASH, identifying advanced fibrosis and providing appropriate treatment for averting disease progression is vital.

A discrete choice experiment to elicit preferences for a liver screening programme in Queensland, Australia: a mixed methods study to select attributes and levels.

BACKGROUND: In Australia, the overall prevalence of liver disease is increasing. Maximising uptake of community screening programmes by understanding patient preferences is integral to developing consumer-centred care models for liver disease. Discrete choice experiments (DCEs) are widely used to elicit preferences for various healthcare services. Attribute development is a vital component of a well-designed DCE and should be described in sufficient detail for others to assess the validity of outcomes. Hence, this study aimed to create a list of potential attributes and levels which can be used in a DCE study to elicit preferences for chronic liver disease screening programmes. METHODS: Key attributes were developed through a multi-stage, mixed methods design. Focus groups were held with consumers and health care providers on attributes of community screening programmes for liver disease. Stakeholders then prioritised attributes generated from the focus group in order of importance via an online prioritisation survey. The outcomes of the prioritisation exercise were then reviewed and refined by an expert panel to ensure clinically meaningful levels and relevance for a DCE survey. RESULTS: Fifteen attributes were generated during the focus group sessions deemed necessary to design liver disease screening services. Outcomes of the prioritisation exercise and expert panel stages recognised five attributes, with three levels each, for inclusion in a DCE survey to elicit consumer preferences for community screening for liver disease. This study also highlights broader social issues such as the stigma around liver disease that require careful consideration by policy makers when designing or implementing a liver screening programme. CONCLUSIONS: The attributes and levels identified will inform future DCE surveys to understand consumer preferences for community screening programmes for liver disease. In addition, the outcomes will help inform the implementation of the LOCATE-NAFLD programme in real-world practice, and could be relevant for other liver and non-liver related chronic disease screening programmes.

Blood-brain barrier water exchange measurements using contrast-enhanced ASL.

A technique for quantifying regional blood-brain barrier (BBB) water exchange rates using contrast-enhanced arterial spin labelling (CE-ASL) is presented and evaluated in simulations and in vivo. The two-compartment ASL model describes the water exchange rate from blood to tissue, k b , but to estimate k b in practice it is necessary to separate the intra- and extravascular signals. This is challenging in standard ASL data owing to the small difference in T 1 values. Here, a gadolinium-based contrast agent is used to increase this T 1 difference and enable the signal components to be disentangled. The optimal post-contrast blood T 1 ( T 1 , b post ) at 3 T was determined in a sensitivity analysis, and the accuracy and precision of the method quantified using Monte Carlo simulations. Proof-of-concept data were acquired in six healthy volunteers (five female, age range 24-46 years). The sensitivity analysis identified the optimal T 1 , b post at 3 T as 0.8 s. Simulations showed that k b could be estimated in individual cortical regions with a relative error ϵ < 1 % and coefficient of variation CoV = 30 %; however, a high dependence on blood T 1 was also observed. In volunteer data, mean parameter values in grey matter were: arterial transit time t A = 1 . 15 ± 0 . 49 s, cerebral blood flow f = 58 . 0 ± 14 . 3 mL blood/min/100 mL tissue and water exchange rate k b = 2 . 32 ± 2 . 49 s-1 . CE-ASL can provide regional BBB water exchange rate estimates; however, the clinical utility of the technique is dependent on the achievable accuracy of measured T 1 values.

Lower prevalence of elevated liver stiffness measurements in people with type 2 diabetes taking sodium-glucose co-transporter 2 inhibitors or glucagon-like peptide-1 receptor agonists.

INTRODUCTION AND OBJECTIVES: Among people with type 2 diabetes (T2D), non-alcoholic fatty liver disease (NAFLD) is very common and has an increased risk of clinically significant liver disease. The use of sodium-glucose co-transporter 2 (SGLT2i) inhibitors and glucagon-like peptide-1 (GLP-1a) receptor agonists is endorsed to reduce major cardiovascular events and/or progression of chronic kidney disease. Their prevalence of use in people with T2D and co-existent NAFLD remains unclear. We sought to determine the prevalence of use of these medications at two different time periods, and their association with prevalence of clinically significant liver disease. MATERIALS AND METHODS: Consecutive people with type 2 diabetes (T2D) and non-alcoholic fatty liver disease (NAFLD) were recruited from diabetes clinics between Jun-2021 and Jun-2022 ('current' cohort). Liver stiffness measurements (LSM) using FibroScan were performed. Medication data were collected prospectively at recruitment and verified with the dispensing pharmacy or general practitioner medical records. Data for a historical cohort with NAFLD and T2D recruited from the same clinics during 2015-2017 ('historical' cohort) were available. Logistic regression was used to evaluate factors associated with LSM <8.0 or ≥8 kPa (clinically significant fibrosis). RESULTS: There were 292 participants, 177 in the historical cohort and 115 in the current cohort. In the current cohort, 57.4% of patients with T2D and NAFLD were taking a GLP-1a and 42.6% were taking a SGLT2i; a 2.6 to 3.4-fold higher prevalence than in 2015-2017. A lower proportion of the current cohort (23.9% compared to 38.4%) had clinically significant fibrosis (LSM ≥8 kPa; p = 0.012). When the cohorts were pooled and differences adjusted for in multivariable logistic regression analysis, patients taking a GLP-1a or a SGLT2i were 2 times more likely to have a lower LSM (<8 kPa) compared to patients not taking these drugs (OR=2.05, 95%CI 1.07-3.94, p = 0.03 and OR 2.07 95%CI 1.04-4.11, p = 0.04, respectively). CONCLUSIONS: The observation of a lower LSM in people taking SGLT2i and/or GLP-1a following adjustment for other relevant clinico-demographic variables provides support for clinical trials to assess their efficacy in reducing the progression of NAFLD.

Venoarterial Extracorporeal Membrane Oxygenation With or Without Advanced Intervention for Massive Pulmonary Embolism.

INTRODUCTION: Massive pulmonary embolism (MPE) is a rare but highly fatal condition. Our study's objective was to evaluate the association between advanced interventions and survival among patients with MPE treated with venoarterial extracorporeal membrane oxygenation (VA-ECMO). METHODS: This is a retrospective review of the Extracorporeal Life Support Organization (ELSO) registry data. We included adult patients with MPE who were treated with VA-ECMO during 2010-2020. Our Primary outcome was survival to hospital discharge; secondary outcomes were ECMO duration among survivors and rates of ECMO-related complications. Clinical variables were compared using the Pearson chi-square and Kruskal-Wallis H tests. RESULTS: We included 802 patients; 80 (10%) received SPE and 18 (2%) received CDT. Overall, 426 (53%) survived to discharge; survival was not significantly different among those treated with SPE or CDT on VA-ECMO (70%) versus VA-ECMO alone (52%) or SPE or CDT before VA-ECMO (52%). Multivariable regression found a trend towards increased survival among those treated with SPE or CDT while on ECMO (AOR 1.8, 95% CI 0.9-3.6), but no significant correlation. There was no association between advanced interventions and ECMO duration among survivors, or rates of ECMO-related complications. CONCLUSION: Our study found no difference in survival in patients with MPE who received advanced interventions prior to ECMO, and a slight non-significant benefit in those who received advanced interventions while on ECMO.

Early veno-venous extracorporeal membrane oxygenation is an effective strategy for traumatically injured patients presenting with refractory respiratory failure.

BACKGROUND: Venovenous extracorporeal membrane oxygenation (VV ECMO) is used for respiratory failure when standard therapy fails. Optimal trauma care requires patients be stable enough to undergo procedures. Early VV ECMO (EVV) to stabilize trauma patients with respiratory failure as part of resuscitation could facilitate additional care. As VV ECMO technology is portable and prehospital cannulation possible, it could also be used in austere environments. We hypothesize that EVV facilitates injury care without worsening survival. METHODS: Our single center, retrospective cohort study included all trauma patients between January 1, 2014, and August 1, 2022, who were placed on VV ECMO. Early VV was defined as cannulation ≤48 hours from arrival with subsequent operation for injuries. Data were analyzed with descriptive statistics. Parametric or nonparametric statistics were used based on the nature of the data. After testing for normality, significance was defined as a p < 0.05. Logistic regression diagnostics were performed. RESULTS: Seventy-five patients were identified and 57 (76%) underwent EVV. There was no difference in survival between the EVV and non-EVV groups (70% vs. 61%, p = 0.47). Age, race, and gender did not differ between EVV survivors and nonsurvivors. Time to cannulation (4.5 hours vs. 8 hours, p = 0.39) and injury severity scores (34 vs. 29, p = 0.74) were similar. Early VV survivors had lower lactic acid levels precannulation (3.9 mmol/L vs. 11.9 mmol/L, p < 0.001). A multivariable logistic regression analysis examining admission and precannulation laboratory and hemodynamic values demonstrated that lower precannulation lactic acid levels predicted survival (odds ratio, 1.2; 95% confidence interval, 1.02-1.5; p = 0.03), with a significant inflection point of 7.4 mmol/L corresponding to decreased survival at hospital discharge. CONCLUSION: Patients undergoing EVV did not have increased mortality compared with the overall trauma VV ECMO population. Early VV resulted in ventilatory stabilization that allowed subsequent procedural treatment of injuries. LEVEL OF EVIDENCE: Therapeutic Care/Management; Level III.

Low Prevalence of Use of Allied Health and Community Services for Patients with Cirrhosis in Australia: A Need for Greater Engagement.

Background: Psychosocial, lifestyle and practical needs are not routinely attended to during outpatient hepatology management, and little is known about the type and effectiveness of support services accessed by patients with cirrhosis. We quantified the type and use of community and allied health services in patients with cirrhosis. Methods: The study included 562 Australian adults with a diagnosis of cirrhosis. Health service use was assessed via questionnaire and via linkage to the Australian Medicare Benefits Schedule. Patient needs were assessed using the Supportive Needs Assessment tool for Cirrhosis (SNAC). Results: Although most patients (85.9%) used at least one community/allied health service for support with their liver disease, many reported requiring additional help with psychosocial (67.4%), lifestyle (34.3%) or practical needs (21.9%) that were not met by available services, or patients did not access services. A multidisciplinary care plan or case conference (in the 12 months prior to recruitment) was accessed by 48% of patients, 56.2% reported the use of a general practitioner for support with cirrhosis, and a dietician was the allied health clinician most accessed by patients (45.9%). Despite the high prevalence of psychosocial needs, there was relatively limited use of mental health and social work services (14.1% of patients reported the use of a psychologist), confirmed by a low prevalence of use of mental health services (17.7%) in the linked data. Conclusion: Patients with cirrhosis who have unmet complex physical and psychosocial needs require better strategies to increase their engagement with allied health and community services.

Filter exchange imaging with crusher gradient modelling detects increased blood-brain barrier water permeability in response to mild lung infection.

Blood-brain barrier (BBB) dysfunction occurs in many brain diseases, and there is increasing evidence to suggest that it is an early process in dementia which may be exacerbated by peripheral infection. Filter-exchange imaging (FEXI) is an MRI technique for measuring trans-membrane water exchange. FEXI data is typically analysed using the apparent exchange rate (AXR) model, yielding estimates of the AXR. Crusher gradients are commonly used to remove unwanted coherence pathways arising from longitudinal storage pulses during the mixing period. We first demonstrate that when using thin slices, as is needed for imaging the rodent brain, crusher gradients result in underestimation of the AXR. To address this, we propose an extended crusher-compensated exchange rate (CCXR) model to account for diffusion-weighting introduced by the crusher gradients, which is able to recover ground truth values of BBB water exchange (kin) in simulated data. When applied to the rat brain, kin estimates obtained using the CCXR model were 3.10 s-1 and 3.49 s-1 compared to AXR estimates of 1.24 s-1 and 0.49 s-1 for slice thicknesses of 4.0 mm and 2.5 mm respectively. We then validated our approach using a clinically relevant Streptococcus pneumoniae lung infection. We observed a significant 70 ± 10% increase in BBB water exchange in rats during active infection (kin = 3.78 ± 0.42 s-1) compared to before infection (kin = 2.72 ± 0.30 s-1; p = 0.02). The BBB water exchange rate during infection was associated with higher levels of plasma von Willebrand factor (VWF), a marker of acute vascular inflammation. We also observed 42% higher expression of perivascular aquaporin-4 (AQP4) in infected animals compared to non-infected controls, while levels of tight junction proteins remain consistent between groups. In summary, we propose a modelling approach for FEXI data which removes the bias in estimated water-exchange rates associated with the use of crusher gradients. Using this approach, we demonstrate the impact of peripheral infection on BBB water exchange, which appears to be mediated by endothelial dysfunction and associated with an increase in perivascular AQP4.