Prevalence and Survival of Prolonged Venovenous Extracorporeal Membrane Oxygenation for Acute Respiratory Distress Syndrome: An Analysis of the Extracorporeal Life Support Organization Registry

OBJECTIVES

To examine trends in utilization and outcomes among patients with the acute respiratory distress syndrome (ARDS) requiring prolonged venovenous extracorporeal membrane oxygenation (VV ECMO) support.

DESIGN

Retrospective observational cohort study.

SETTING

Adult patients in the Extracorporeal Life Support Organization registry.

PATIENTS

Thirteen thousand six hundred eighty-one patients that required ECMO for the support of ARDS between January 2012 and December 2022.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Mortality while supported with VV ECMO and survival to hospital discharge based on ECMO duration were examined utilizing multivariable logistic regression. Among the 13,681 patients supported with VV ECMO, 4,040 (29.5%) were supported for greater than or equal to 21 days and 975 (7.1%) for greater than or equal to 50 days. Patients supported with prolonged VV ECMO were less likely to be discharged alive from the hospital compared with those with short duration of support (46.5% vs. 59.7%; p < 0.001). However, among patients supported with VV ECMO greater than or equal to 21 days, duration of extracorporeal life support was not significantly associated with mortality (odds ratio [OR], 0.99; 95% CI, 0.98-1.01; p = 0.87 and adjusted OR, 0.99; 95% CI, 0.97-1.02; p = 0.48). Even in those supported with VV ECMO for at least 120 days (n = 113), 52 (46.0%) of these patients were ultimately discharged alive from the hospital.

CONCLUSIONS

Prolonged VV ECMO support of ARDS has increased and accounts for a substantial portion of cases. Among patients that survive for greater than or equal to 21 days while receiving VV ECMO support, duration is not predictive of survival to hospital discharge and clinical recovery may occur even after very prolonged VV ECMO support.

Multi-pronged analysis of pediatric low-grade glioma reveals a unique tumor microenvironment associated with BRAF alterations

Pediatric low-grade gliomas (pLGG) comprise 35% of all brain tumors. Despite favorable survival, patients experience significant morbidity from disease and treatments. A deeper understanding of pLGG biology is essential to identify novel, more effective, and less toxic therapies. We utilized single cell RNA sequencing (scRNA-seq), spatial transcriptomics, and cytokine analyses to characterize and understand tumor and immune cell heterogeneity across pLGG. scRNA-seq revealed tumor and immune cells within the tumor microenvironment (TME). Tumor cell subsets revealed a developmental hierarchy with progenitor and mature cell populations. Immune cells included myeloid and lymphocytic cells. There was a significant difference between the prevalence of two major myeloid subclusters between pilocytic astrocytoma (PA) and ganglioglioma (GG). Bulk and single-cell cytokine analyses evaluated the immune cell signaling cascade with distinct immune phenotypes among tumor samples. KIAA1549-BRAF tumors appeared more immunogenic, secreting higher levels of immune cell activators and chemokines, compared to BRAF V600E tumors. Spatial transcriptomics revealed the differential gene expression of these chemokines and their location within the TME. A multi-pronged analysis of pLGG demonstrated the complexity of the pLGG TME and differences between genetic drivers that may influence their response to immunotherapy. Further investigation of immune cell infiltration and tumor-immune interactions is warranted.

Key points

There is a developmental hierarchy in neoplastic population comprising of both progenitor-like and mature cell types in both PA and GG.A more immunogenic, immune activating myeloid population is present in PA compared to GG. Functional analysis and spatial transcriptomics show higher levels of immune mobilizing chemokines in KIAA1549-BRAF fusion PA tumor samples compared to BRAF V600E GG samples.

Importance of the Study

While scRNA seq provides information on cellular heterogeneity within the tumor microenvironment (TME), it does not provide a complete picture of how these cells are interacting or where they are located. To expand on this, we used a three-pronged approach to better understand the biology of pediatric low-grade glioma (pLGG). By analyzing scRNA-seq, secreted cytokines and spatial orientation of cells within the TME, we strove to gain a more complete picture of the complex interplay between tumor and immune cells within pLGG. Our data revealed a complex heterogeneity in tumor and immune populations and identified an interesting difference in the immune phenotype among different subtypes.

Economic review of point-of-care EEG

Aims: Point-of-care electroencephalogram (POC-EEG) is an acute care bedside screening tool for the identification of nonconvulsive seizures (NCS) and nonconvulsive status epilepticus (NCSE). The objective of this narrative review is to describe the economic themes related to POC-EEG in the United States (US).Materials and methods: We examined peer-reviewed, published manuscripts on the economic findings of POC-EEG for bedside use in US hospitals, which included those found through targeted searches on PubMed and Google Scholar. Conference abstracts, gray literature offerings, frank advertisements, white papers, and studies conducted outside the US were excluded.Results: Twelve manuscripts were identified and reviewed; results were then grouped into four categories of economic evidence. First, POC-EEG usage was associated with clinical management amendments and antiseizure medication reductions. Second, POC-EEG was correlated with fewer unnecessary transfers to other facilities for monitoring and reduced hospital length of stay (LOS). Third, when identifying NCS or NCSE onsite, POC-EEG was associated with greater reimbursement in Medical Severity-Diagnosis Related Group coding. Fourth, POC-EEG may lower labor costs via decreasing after-hours requests to EEG technologists for conventional EEG (convEEG).Limitations: We conducted a narrative review, not a systematic review. The studies were observational and utilized one rapid circumferential headband system, which limited generalizability of the findings and indicated publication bias. Some sample sizes were small and hospital characteristics may not represent all US hospitals. POC-EEG studies in pediatric populations were also lacking. Ultimately, further research is justified.Conclusions: POC-EEG is a rapid screening tool for NCS and NCSE in critical care and emergency medicine with potential financial benefits through refining clinical management, reducing unnecessary patient transfers and hospital LOS, improving reimbursement, and mitigating burdens on healthcare staff and hospitals. Since POC-EEG has limitations (i.e. no video component and reduced montage), the studies asserted that it did not replace convEEG.

Objective Methods of Assessing Fluid Status to Optimize Volume Management in Kidney Disease and Hypertension: The Importance of Ultrasound

Fluid overload, a prevalent complication in patients with renal disease and hypertension, significantly impacts patient morbidity and mortality. The daily clinical challenges that clinicians face include how to identify fluid overload early enough in the course of the disease to prevent adverse outcomes and to guide and potentially reduce the intensity of the diuresis. Traditional methods for evaluating fluid status, such as pitting edema, pulmonary crackles, or chest radiography primarily assess extracellular fluid and do not accurately reflect intravascular volume status or venous congestion. This review explores the rationale, mechanism, and evidence behind more recent methods used to assess volume status, namely, lung ultrasound, inferior vena cava (IVC) ultrasound, venous excess ultrasound score, and basic and advanced cardiac echocardiographic techniques. These methods offer a more accurate and objective assessment of fluid status, providing real-time, non-invasive measures of intravascular volume and venous congestion. The methods we discuss are primarily used in inpatient settings, but, given the increased pervasiveness of ultrasound technology, some could soon expand to the outpatient setting.

The Impact of Positive Fluid Balance on Sepsis Subtypes: A Causal Inference Study

Introduction

Sepsis, the leading cause of death in hospitalized patients globally, was investigated in this study, examining the varying effects of positive fluid balance on sepsis subtypes through causal inference.

Methods

In this study, data from the eICU database were utilized, extracting 35 features from sepsis patients. Fluid balance during ICU stay was the treatment, and ICU mortality was the primary outcome. Data preprocessing ensured linear assumptions for logistic regression. Binarized positive fluid balance with mortality was examined using DoWhy's logistic regression, while continuous data were analyzed with random forest T-learner. ATE served as the primary metric.

Results

Results revealed that septic patients with higher fluid balance had worse mortality outcomes, with an ATE of 0.042 (95% CI: (0.034, 0.047)) using logistic regression and an ATE of 0.0340 (95% CI: (0.028-0.040)) using T-learner. In the pulmonary sepsis subtype, higher mortality was associated with increased fluid balance, showing an ATE of 0.047 (95% CI: (0.037, 0.055)) using logistic regression and an ATE of 0.28 (95% CI: (0.22, 0.34)) with T-learner. Conversely, urinary sepsis patients had improved mortality with higher fluid balance, presenting an ATE of -0.135 (95% CI: (-0.024, -0.0035)) using logistic regression and an ATE of -0.28 (95% CI: (-0.34, -0.22)) with T-learner.

Conclusion

Our research implies that fluid balance impact on ICU mortality differs among sepsis subtypes. Positive fluid balance raises mortality in sepsis and pulmonary sepsis but may protect against urinary sepsis. Further trials are needed to confirm these findings.

Are Different Modes of Weight Loss Associated with Survival in Oropharyngeal Cancer?

PURPOSE/OBJECTIVE(S)

Patients with oropharyngeal squamous cell carcinomas (OPSCC) often lose weight during radical radiotherapy (RT). Nutritional intervention is required in case of severe weight loss. However, weight loss does not provide full insight into body composition changes. Muscle mass is emerging as an important prognostic factor in cancer patients. We employed on-treatment cone-beam CT (CBCT) scans to monitor muscle mass and weight loss under the hypothesis that different modes of weight loss exist and may impact overall survival (OS).

MATERIALS/METHODS

A retrospective analysis of 197 OPSCC patients treated with definitive or adjuvant (chemo)RT. Weekly weight measurements & CBCTs were collected. Patients were included if at least two time-points were available and the interval between the first and last was between 15-50 days. CBCTs were normalized to account for calibration differences between treatment machines. An in-house deep-learning model automatically segmented the skeletal muscle compartment at C3 on all CBCTs. Segmentations were visually checked and failures removed. Skeletal muscle volume (SMV, in mm3) was extracted after thresholding for intra-muscular fat. Relative changes in weight & SMV were then calculated. Linear models were fitted to each trajectory for every patient and slopes were estimated. The following weight & SMV categories were defined to generate equal groups: lost (more than 0.4 standard deviations (SDs) below the mean (M)), maintained (within +/- 0.4 SDs of M) or gained (more than 0.4 SDs above the M). Table 1 highlights the nine modes of body composition change. The prognostic value of these was investigated in multivariable Cox models accounting for age, sex, disease stage, oropharynx subsite, smoking status, performance status (PS), tumor p16 status, baseline weight & SMV, and treatment prescribed. The primary endpoint was OS.

RESULTS

Mean weight & SMV changes during treatment were -0.047±0.001% & -0.044±0.019% per day. In multivariable analysis, gaining weight & losing SMV was identified as a significant risk factor for OS (p = 0.01, hazard ratio [95% CI]: 4.59 [1.40-15.10]). In this sub-group, mean weight & SMV change were +0.054±0.008% & -0.396±0.030% per day. PS>2 (p<0.001) & lower baseline weight (p = 0.02) were also significantly associated with OS.

CONCLUSION

Patients losing substantial SMV but mildly gaining weight have significantly worse OS than others. This suggests there exists a group of patients where nutritional support is needed, but not offered because they maintain weight during treatment. Although our results need validation, continual monitoring of muscle condition during RT would allow these patients to be identified and promptly targeted for nutritional support.

Registration of essential medicines in Kenya, Tanzania and Uganda: a retrospective analysis

OBJECTIVES

To audit national drug registers (NDRs) in Kenya, United Republic of Tanzania and Uganda with respect to national Essential Medicine Lists (EMLs) and to conduct an analysis of highly registered products including a sub-analysis of highly registered antimicrobial products.

DESIGN

Retrospective analysis of registration of essential medicines and medicinal products on NDRs as of February 2018.

SETTING

Not applicable.

PARTICIPANTS

None.

MAIN OUTCOME MEASURES

Registration status of essential medicines by country, essential medicine status of registered products by country and medicines with more than 50 registrations across all three countries.

RESULTS

A high proportion of essential medicines are not registered: Kenya 28% (175/632), United Republic of Tanzania 50% (400/797) and Uganda 40% (266/663). Of registered products on the NDRs, more than half are not essential: Kenya 71% (4350/6151), United Republic of Tanzania 64% (2278/3590) and Uganda 58% (2268/3896). When the three NDRs were combined, there were 42 medicines with over 50 registered products, accounting for 30% (4153/13637) of products, many of which were non-essential.

CONCLUSIONS

Non-registration of essential medicines is a barrier to availability. Over-registration of medicines, particularly non-essential medicines, diverts regulatory resources towards registering non-priority and, sometimes, clinically sub-optimal medicines. The East African Community Medicines Registration Harmonization Project has the potential to improve access to key medicines if registration of essential medicines is prioritised and registration of non-essential medicines is restricted.

Aryl hydrocarbon receptor utilises cellular zinc signals to maintain the gut epithelial barrier

Zinc and plant-derived ligands of the aryl hydrocarbon receptor (AHR) are dietary components affecting intestinal epithelial barrier function. Here, we explore whether zinc and the AHR pathway are linked. We show that dietary supplementation with an AHR pre-ligand offers protection against inflammatory bowel disease in a mouse model while protection fails in mice lacking AHR in the intestinal epithelium. AHR agonist treatment is also ineffective in mice fed zinc depleted diet. In human ileum organoids and Caco-2 cells, AHR activation increases total cellular zinc and cytosolic free Zn2+ concentrations through transcription of genes for zinc importers. Tight junction proteins are upregulated through zinc inhibition of nuclear factor kappa-light-chain-enhancer and calpain activity. Our data show that AHR activation by plant-derived dietary ligands improves gut barrier function at least partly via zinc-dependent cellular pathways, suggesting that combined dietary supplementation with AHR ligands and zinc might be effective in preventing inflammatory gut disorders.

Children's Oncology Group's 2023 blueprint for research: Young investigators

The Children's Oncology Group (COG) Young Investigators (YI) Committee is an administrative committee in which liaisons represent 30 COG committees, and was created to facilitate the integration of YIs into the organization, and prepare them for future COG leadership roles. The mentorship program has mentored over 400 YIs since 2005 and currently has 175 active participants. The COG YI Master Roster is a database YIs can join, which allows them to post their interests and accomplishments to COG leadership, and 321 YIs have already joined this list. The YI Committee has held virtual symposia designed to describe how COG operates and provide guidance on how YIs can reach their goals; over 300 YIs have attended these since 2021 and have consistently rated them as helpful. Through these and other elements of the program, the YI Committee remains committed to developing a future pipeline of new investigators.

Implementation and impact of a point of care electroencephalography platform in a community hospital: a cohort study

Objective

To determine the clinical and financial feasibility of implementing a poc-EEG system in a community hospital.

Design

Data from a prospective cohort displaying abnormal mentation concerning for NCSE or rhythmic movements due to potential underlying seizure necessitating EEG was collected and compared to a control group containing patient data from 2020.

Setting

A teaching community hospital with limited EEG support.

Patients

The study group consisted of patients requiring emergent EEG during hours when conventional EEG was unavailable. Control group is made up of patients who were emergently transferred for EEG during the historical period.

Interventions

Application and interpretation of Ceribell®, a poc-EEG system.

Measurement and main results

88 patients were eligible with indications for poc-EEG including hyperkinetic movements post-cardiac arrest (19%), abnormal mentation after possible seizure (46%), and unresponsive patients with concern for NCSE (35%). 21% had seizure burden on poc-EEG and 4.5% had seizure activity on follow-up EEG. A mean of 1.1 patients per month required transfer to a tertiary care center for continuous EEG. For the control period, a total of 22 patients or a mean of 2 patients per month were transferred for emergent EEG. Annually, we observed a decrease in the number of transferred patients in the post-implementation period by 10.8 (95% CI: -2.17-23.64, p = 0.1). Financial analysis of the control found the hospital system incurred a loss of $3,463.11 per patient transferred for an annual loss of $83,114.64. In the study group, this would compute to an annual loss of $45,713.05 for an overall decrease in amount lost of $37,401.59. We compared amount lost per patient between historical controls and study patients. Implementation of poc-EEG resulted in an overall decrease in annual amount lost of $37,401.59 by avoidance of transfer fees. We calculated the amount gained per patient in the study group to be $13,936.44. To cover the cost of the poc-EEG system, 8.59 patients would need to avoid transfer annually.

Conclusion

A poc-EEG system can be safely implemented in a community hospital leading to an absolute decrease in transfers to tertiary hospital. This decrease in patient transfers can cover the cost of implementing the poc-EEG system. The additional benefits from transfer avoidance include clinical benefits such as rapid appropriate treatment of seizures and avoidance of unnecessary treatment as well as negating transfer risk and keeping the patient at their local hospital.

Hip Abductor Reconstruction with the Use of Mesh and Distal Cerclage Cable Fixation: A Case Report and Surgical Technique

CASE

This is a case of a 71-year-old female patient with recurrent instability and complex hip abductor deficiency after total hip arthroplasty (THA) who was treated successfully with an abductor reconstruction with gluteal transfer with mesh reconstruction. The patient returned to nonassisted ambulation with no further THA dislocations at the 1-year follow-up.

CONCLUSION

Abductor deficiencies after THA are complex and have a high potential for long-term disability if not properly diagnosed and treated. A modified gluteal transfer with mesh reconstruction and distal fixation with cerclage cable allowed for sustained restoration of functional hip abduction and stability after revision THA.

Timing of invasive mechanical ventilation and death in critically ill adults with COVID-19: A multicenter cohort study

PURPOSE

To investigate if the timing of initiation of invasive mechanical ventilation (IMV) for critically ill patients with COVID-19 is associated with mortality.

MATERIALS AND METHODS

The data for this study were derived from a multicenter cohort study of critically ill adults with COVID-19 admitted to ICUs at 68 hospitals across the US from March 1 to July 1, 2020. We examined the association between early (ICU days 1-2) versus late (ICU days 3-7) initiation of IMV and time-to-death. Patients were followed until the first of hospital discharge, death, or 90 days. We adjusted for confounding using a multivariable Cox model.

RESULTS

Among the 1879 patients included in this analysis (1199 male [63.8%]; median age, 63 [IQR, 53-72] years), 1526 (81.2%) initiated IMV early and 353 (18.8%) initiated IMV late. A total of 644 of the 1526 patients (42.2%) in the early IMV group died, and 180 of the 353 (51.0%) in the late IMV group died (adjusted HR 0.77 [95% CI, 0.65-0.93]).

CONCLUSIONS

In critically ill adults with respiratory failure from COVID-19, early compared to late initiation of IMV is associated with reduced mortality.

MRI-Guided Focused Ultrasound Blood-Brain Barrier Opening Increases Drug Delivery and Efficacy in a Diffuse Midline Glioma Mouse Model

Diffuse intrinsic pontine glioma (DIPG) is the most common and deadliest pediatric brainstem tumor and is difficult to treat with chemotherapy in part due to the blood-brain barrier (BBB). Focused ultrasound (FUS) and microbubbles (MBs) have been shown to cause BBB disruption (BBBD), allowing larger chemotherapeutics to enter the parenchyma. Panobinostat is an example of a promising in vitro agent in DIPG with poor clinical efficacy due to low BBB penetrance. In this study, we hypothesized that using FUS to disrupt the BBB allows higher concentrations of panobinostat to accumulate in the tumor, providing a therapeutic effect. Mice were orthotopically injected with a patient-derived DMG cell line, BT-245. MRI was used to guide FUS/MB (1.5 MHz, 0.615 MPa PNP, 1 Hz PRF, 10 ms PL, 3 min treatment time) / (25 µL/kg, IV) targeting to the tumor location. In animals receiving panobinostat (10 mg/kg, IP) in combination with FUS/MB, a 3-fold increase in tumor panobinostat concentration was observed, with only insignificant increase of the drug in the forebrain. In mice receiving three weekly treatments, the combination of panobinostat and FUS/MB led to a 71% reduction of tumor volumes by MRI ( p = 0.01). Furthermore, FUS/MB improved the mean survival from 21 to 31 days ( p < 0.0001). Our study demonstrates that FUS-mediated BBBD can increase the delivery of panobinostat to an orthotopic DMG tumor, providing a strong therapeutic effect and increased survival.

One Sentence Summary

FUS and microbubbles can increase the delivery of panobinostat to a patient-derived xenograft (PDX) orthotopic DMG tumor, providing a strong therapeutic effect and increased survival.

The cycle ergometer test is not a reliable alternative to the countermovement jump in the assessment of power output

Background

Rugby union is a physically demanding collision sport that requires optimal neuromuscular function for maximal power output, with mechanical power an integral component of performance. Peak power (P_p) and relative P_p are parameters of neuromuscular function commonly assessed through the countermovement jump (CMJ) as a measure of fatigue. The Wattbike cycle ergometer test (CET) is a non-load bearing method of evaluating lower limb power. The cost-effective CET could therefore offer a viable alternative to the CMJ.

Objectives

This study aimed to determine the concurrent validity of the CMJ and CET.

Methods

Thirty-eight professional rugby union players performed twelve CMJs on a force platform with four loads (bodyweight: BW-CMJ; 20kg: 20-CMJ; 40kg: 40-CMJ and 60kg: 60-CMJ) and a six second peak power (6PPO) CET assessment on a Wattbike ergometer.

Results

CMJ power outputs were [BW-CMJ: P_p - 3101±648 W; 20-CMJ: P_p - 2724±513 W; 40-CMJ: P_p - 2490±496 W; 60-CMJ: P_p - 2238±366 W] and CET [P_p - 1310±161 W]. None of the CMJ-P_p values showed relationships with any CET power variables. Large (r = 0.51-0.63; p = 0.000 - 0.001) relationships were found to be between relative CMJ and relative CET power outputs. Bland-Altman plots, which were used to determine the level of agreement between the two assessments, showed the agreement between the tests was poor.

Conclusion

Though positive relationships existed between relative CMJ and relative CET power variables, analyses of the level of agreement in the Bland-Altman plots suggest that the two power assessment methods are not interchangeable measures of power.

RAB7 deficiency impairs pulmonary artery endothelial function and promotes pulmonary hypertension

Pulmonary arterial hypertension (PAH) is a devastating and progressive disease with limited treatment options. Endothelial dysfunction plays a central role in development and progression of PAH, yet the underlying mechanisms are incompletely understood. The endosome-lysosome system is important to maintain cellular health and the small GTPase RAB7 regulates many functions of this system. Here, we explored the role of RAB7 in endothelial cell (EC) function and lung vascular homeostasis. We found reduced expression of RAB7 in ECs from PAH patients. Endothelial haploinsufficiency of RAB7 caused spontaneous PH in mice. Silencing of RAB7 in ECs induced broad changes in gene expression revealed via RNA sequencing and RAB7 silenced ECs showed impaired angiogenesis, expansion of a senescent cell fraction, combined with impaired endolysosomal trafficking and degradation, which suggests inhibition of autophagy at the pre-degradation level. Further, mitochondrial membrane potential and oxidative phosphorylation were decreased, and glycolysis was enhanced. Treatment with the RAB7 activator ML-098 reduced established PH in chronic hypoxia/SU5416 rats. In conclusion, we demonstrate here for the first time the fundamental impairment of EC function by loss of RAB7 that leads to PH and show RAB7 activation as a potential therapeutic strategy in a preclinical model of PH.

Deploying Machine Learning Based Segmentation for Scientific Imaging Analysis at Synchrotron Facilities

Scientific user facilities present a unique set of challenges for image processing due to the large volume of data generated from experiments and simulations. Furthermore, developing and implementing algorithms for real-time processing and analysis while correcting for any artifacts or distortions in images remains a complex task, given the computational requirements of the processing algorithms. In a collaborative effort across multiple Department of Energy national laboratories, the "MLExchange" project is focused on addressing these challenges. MLExchange is a Machine Learning framework deploying interactive web interfaces to enhance and accelerate data analysis. The platform allows users to easily upload, visualize, label, and train networks. The resulting models can be deployed on real data while both results and models could be shared with the scientists. The MLExchange web-based application for image segmentation allows for training, testing, and evaluating multiple machine learning models on hand-labeled tomography data. This environment provides users with an intuitive interface for segmenting images using a variety of machine learning algorithms and deep-learning neural networks. Additionally, these tools have the potential to overcome limitations in traditional image segmentation techniques, particularly for complex and low-contrast images.

Case report: Isoflurane therapy in a case of status asthmaticus requiring extracorporeal membrane oxygenation

Volatile anesthetics have been described as a rescue therapy for patients with refractory status asthmaticus (SA), and the use of isoflurane for this indication has been reported since the 1980s. Much of the literature reports good outcomes when inhaled isoflurane is used as a rescue therapy for patients for refractory SA. Venovenous (VV) extracorporeal membrane oxygenation (ECMO) is a mode of mechanical circulatory support that is usually employed as a potentially lifesaving intervention in patients who have high risk of mortality, primarily for underlying pulmonary pathology. VV ECMO is usually only considered in cases where patients gas exchange cannot be satisfactorily maintained by conventional therapy and mechanical ventilation strategies. We report the novel use of isoflurane delivered systemically as treatment for severe refractory SA in a patient on VV ECMO. A 51-year-old male with a history of asthma was transferred from another institution for management of severe SA. He was intubated at the referring hospital after failing non-invasive ventilation. Initial arterial blood gas (ABG) showed pH 7.21, partial pressure of carbon dioxide (PCO2) >95 mmHg, and partial pressure of oxygen (PaO2) 60 mmHg. VV ECMO was initiated on hospital day (HD) 1 due to refractory respiratory acidosis. After ECMO initiation, acid-base status improved, however, severe bronchospasm persisted and intrinsic positive end expiratory pressure (PEEP) was measured at 18 cm H2O. Systemic paralysis was employed, respiratory rate (RR) was reduced to 4 breaths per minute. This degree of bronchospasm did not allow for ECMO weaning. On HD 5, the patient received systemic isoflurane via the ECMO circuit for 20 h. The following morning, intrinsic PEEP was 4 cm H2O, and wheezing improved. He was decannulated from VV ECMO on HD 10 and extubated on HD 17. Inhaled isoflurane therapy in patients on VV ECMO for refractory SA has shown good results, but requires delivery of the medication via anesthesia ventilators. Our case highlights an effective alternative, systemic delivery of anesthetic via the ECMO circuit, as it is often difficult and dangerous to transport these patients to the operating room (OR) or have an intensive care unit (ICU) room adjusted to accommodate an anesthesia ventilator.

MLExchange: A web-based platform enabling exchangeable machine learning workflows for scientific studies

Machine learning (ML) algorithms are showing a growing trend in helping the scientific communities across different disciplines and institutions to address large and diverse data problems. However, many available ML tools are programmatically demanding and computationally costly. The MLExchange project aims to build a collaborative platform equipped with enabling tools that allow scientists and facility users who do not have a profound ML background to use ML and computational resources in scientific discovery. At the high level, we are targeting a full user experience where managing and exchanging ML algorithms, workflows, and data are readily available through web applications. Since each component is an independent container, the whole platform or its individual service(s) can be easily deployed at servers of different scales, ranging from a personal device (laptop, smart phone, etc.) to high performance clusters (HPC) accessed (simultaneously) by many users. Thus, MLExchange renders flexible using scenarios-users could either access the services and resources from a remote server or run the whole platform or its individual service(s) within their local network.

Mitochondrial dynamics involves molecular and mechanical events in motility, fusion and fission

Mitochondria are cell organelles that play pivotal roles in maintaining cell survival, cellular metabolic homeostasis, and cell death. Mitochondria are highly dynamic entities which undergo fusion and fission, and have been shown to be very motile in vivo in neurons and in vitro in multiple cell lines. Fusion and fission are essential for maintaining mitochondrial homeostasis through control of morphology, content exchange, inheritance of mitochondria, maintenance of mitochondrial DNA, and removal of damaged mitochondria by autophagy. Mitochondrial motility occurs through mechanical and molecular mechanisms which translocate mitochondria to sites of high energy demand. Motility also plays an important role in intracellular signaling. Here, we review key features that mediate mitochondrial dynamics and explore methods to advance the study of mitochondrial motility as well as mitochondrial dynamics-related diseases and mitochondrial-targeted therapeutics.

Identifying safe corridors for anterior pelvic percutaneous instrumentation using computed tomography-based anatomical relationships

INTRODUCTION

Percutaneous anterior pelvic ring instrumentation is performed for retrograde screw fixation of ramus fractures, as well as for repair of pubic symphysis diastasis. The anatomic relationships of critical structures around the anterior pelvic ring, such as the spermatic cord and round ligament, have been described in only a few studies regarding the risk of iatrogenic injury during surgery. Our goal is to further describe these relationships, as well as provide radiographic information on safe corridors for percutaneous fixation.

METHODS

Eighty (80) axial computed tomography scans of the abdomen, obtained for non traumatic diagnostic purposes and screened for prior abdominal trauma or procedures, were evaluated by 3 fellowship trained radiologists. Mid-symphyseal cuts were used to obtain several measurements relative to the spermatic cords (SC) or round ligaments (RL): inter-cord or inter-ligament distance, skin to cortex of symphysis distance (vertical), skin to cortex of symphysis distance (oblique), safe corridor distance (between SC/RL and femoral triangle), center safe angle (relative to bilateral ischia), maximal safe angle, and minimal safe angle.

RESULTS

There were 41 male and 39 female scans included in the final analysis. The average inter-cord distance was 50.2 mm, skin to cortex vertical distance of 43.0 mm, skin to cortex oblique distance of 83.5 mm, safe corridor distance 26.3 mm, center safe angle 19.3˚, maximal safe angle 32.3˚, and minimal safe angle 13.6˚. These were further broken down by range and gender in Table 1. Agreement between radiologists was high for these different measurements with the exception of the skin to cortex oblique distance in female patients and the maximal safe angle in female patients, due to absence of round ligament in a majority of the scans. The round ligament was only present at the mid-symphyseal level for our three reviewers in 37/39, 36/39, and 24/39 of female patient scans.

CONCLUSIONS

We have identified defined safe corridors for instrumentation of the anterior pelvic ring that can assist the surgeon in percutaneous application of fixation for fracture care.

Stabilized Radiation Pressure Acceleration and Neutron Generation in Ultrathin Deuterated Foils

Premature relativistic transparency of ultrathin, laser-irradiated targets is recognized as an obstacle to achieving a stable radiation pressure acceleration in the "light sail" (LS) mode. Experimental data, corroborated by 2D PIC simulations, show that a few-nm thick overcoat surface layer of high Z material significantly improves ion bunching at high energies during the acceleration. This is diagnosed by simultaneous ion and neutron spectroscopy following irradiation of deuterated plastic targets. In particular, copious and directional neutron production (significantly larger than for other in-target schemes) arises, under optimal parameters, as a signature of plasma layer integrity during the acceleration.

DIPG-56. Development and application of a novel antibody against CD99 as a therapeutic strategy in Diffuse Midline Glioma

BACKGROUND: There is an unmet need to identify novel targeted therapies for Diffuse Midline glioma (DMG) which is currently a refractory disease. Recently, we identified high expression of a cell surface antigen, CD99 in H3K27M-mutant expressing DMGs compared to other normal brain counterparts. We developed a novel chimeric CD99 antibody and tested the anti-tumor efficacy of this antibody in vitro and in vivo. METHOD: Bio-legend cell-surface screening was performed in H3K27M-mutant and WT DMG cells. Functional role of CD99 was studied using CD99 proficient and depleted tumors. Designed and synthesized CD99 antibody with a new binding sequence on a human IgG scaffold and performed cell toxicity and growth-inhibitory studies using DMG tumor and normal cells. We also performed these studies in combination with radiation. Multiple patient-derived orthotopic DMG xenograft models was used to test the antibody efficacy. Different antibody delivery routes, that are clinically relevant were investigated. RESULTS: CD99 expression is transcriptionally regulated by H3K27M and is enriched on the cell surface of K27M tumors compared to WT DMG tumors. Our new CD99 antibody (10D1 clone) significantly reduced DIPG tumor cell proliferation in vitro. Intravenous infusion of this antibody in DIPG tumor bearing mice showed complete clearance of tumor that prolonged animal survival suggesting the enhanced anti-tumor efficacy of 10D1-CD99 and importantly, its ability in crossing the blood-brain-barrier and reaching the pons target site. Loco-regional administration of 10D1 showed similar anti-tumor effects even at much reduced antibody concentrations while toxicity to CD99-expressing T cells was minimum. Radiation increased CD99 expression and enhanced the cytotoxic effect of 10D1-CD99. CONCLUSION: We have developed a novel CNS penetrant CD99 antibody that is an attractive therapeutic strategy in treating DMG. 10D1 is currently in development as a therapeutic.

MODL-31. Novel in vivo models of post-radiation recurrent pediatric high-grade glioma show increased susceptibility to MAPK inhibition

BACKGROUND: Pediatric high-grade glioma (pHGG) is the most common cause of childhood cancer mortality, with median survival of less than one year. The standard of care for pHGG includes radiation therapy (RT), but almost all patients who respond initially relapse with aggressive, radiation-resistant disease. Matched primary/recurrent models and effective therapies for recurrent pHGG have not been adequately developed. METHODS: Orthotopic patient derived xenograft (PDX) models of radiation-resistant pHGG were developed by implanting BT245 (H3K27M) and HSJD-GBM-001 (GBM1, H3-wt) cells into mice. Resultant tumors were irradiated at 8Gy (4Gy x 2d) and allowed to regrow. Recurrent, radiation-resistant tumors (BT245MR and GBM1MR) and initial tumors (BT245M and GBM1M) were collected for bulk RNA-Seq analysis and ex vivo cell culture. Dose-response experiments were conducted in explant cells to identify drugs with increased effectiveness against recurrent (MR) cell lines versus wild-type cell lines. RESULTS: In both BT245 and GBM1 explant cells, geneset enrichment analysis (GSEA) showed upregulated mesenchymal (BT245MR: NES=3.4, FDR=0; GBM1MR: NES=2.4, FDR<0.002) and hypoxia-related (BT245MR: NES=3.6, FDR=0; GBM1MR: NES=3.4, FDR=0) pathways. GBM1MR tumors also showed enrichment in MAPK signaling (NES=4.7, FDR=0). RNA processing (NES=-6.5, FDR=0) and translation (NES=-5.8, FDR=0) pathways were depleted in BT245MR cells, and DNA repair pathways (NES=-5.8, FDR=0) were depleted in GBM1MR cells. The MAPK inhibitor trametinib demonstrated increased effectiveness in BT245MR and GBM1MR cell lines versus wild-type controls (BT245 IC50 158.7nM (wt) vs. 56.0 (MR), p<0.05; GBM1 IC50 150.7 (wt) vs. 53.4 (MR), p<0.05). BT245MR and GBM1MR cells reliably form PDX tumors after injection into mice. CONCLUSION: BT245MR and GBM1MR represent novel in vivo models of radiation-resistant pHGG, with gene expression alterations consistent with an irradiated phenotype. GSEA and in vitro dose-response data suggest MAPK inhibition may be effective in radiation-resistant pHGG. We are currently conducting in vivo experiments to validate increased trametinib sensitivity in these models.

HGG-20. PRMT5 promotes the formation and growth of pediatric high-grade glioma by maintaining tumor stem cell populations

BACKGROUND: Pediatric high-grade gliomas (PHGG) are aggressive, undifferentiated CNS tumors comprising two broad subtypes: diffuse midline glioma with H3K27M mutations (DMG) and cortical high-grade glioma (H3K27-wild-type (wt) PHGG). During normal development, PRMT5 promotes stem cell self-renewal through methylation of arginine residues in histone tails. We hypothesized that PRMT5 controls self-renewal essential to the proliferation of PHGG tumor initiating cells (TICs). METHODS: We identified PRMT5 as potentially oncogenic in PHGG through a screen of 4,139 shRNAs targeting 406 genes with epigenetic activity. To elucidate PRMT5’s activity, we used lentiviral shRNA delivery to knock down (KD) PRMT5 expression in four DMG and one H3K27-wt PHGG cell lines. We performed in vitro growth, cell cycle, apoptosis, limiting dilution and bulk RNA-Seq assays to determine the phenotypic effects of PRMT5 KD. To identify PRMT5’s gene targets, we performed cleavage under targets & release using nuclease (CUT&RUN) followed by qPCR and are currently performing CUT&RUN-Seq. We orthotopically implanted PRMT5 KD PHGG cells into mice and tracked survival, tumor growth and tumor histological characteristics. RESULTS: In vitro, PRMT5 KD reduced cell growth (p&lt;0.001), slowed cell cycle progression and increased apoptosis. PRMT KD also slowed neurosphere formation, demonstrating reduced self-renewal (p&lt;7E-9). Geneset expression analysis showed PRMT5 KD reduced expression of self-renewal genes and increased expression of differentiation genes (FDR&lt;0.0001). In vivo, PRMT5 KD reduced tumor growth, as monitored by bioluminescence and MRI, and aggressiveness, based on Ki-67 staining (p&lt;0.05), leading to increased survival (p&lt;0.001). CUT&RUN-qPCR results showed PRMT5 KD led to decreased expression and H3K4me3 promoter occupancy at PAX3, and decreased expression and increased H3K27me3 occupancy at S100A6. PAX3 and S100A6 are oncogenes that preserve TIC self-renewal. CONCLUSION. In vitro experiments show that PRMT5 KD epigenetically reduces TIC self-renewal. In vitro and in vivo, PRMT5 KD reduced PHGG tumor cell growth and aggressiveness.

RONC-05. Peri-transplant Radiation Therapy for Young Children Treated with High-Dose Chemotherapy for Primary Brain Tumors

PURPOSE: The role of peri-transplant radiation therapy (RT) in young children with primary brain tumors is unclear. We characterized our institutional practice patterns and patient outcomes. MATERIALS AND METHODS: The cohort included all patients treated with high-dose chemotherapy for primary brain tumors at our institution from 2011-2017. Rates of local control (LC), progression-free survival (PFS), overall survival (OS), and radiation-associated injury were assessed. RESULTS: Of 37 eligible patients, 29 (78%) received peri-transplant RT at a median age of 4 years. Patients treated with RT were more likely to have metastatic (p=0.0121) and incompletely resected (p=0.056) disease, and to have high-risk histologies including atypical teratoid rhabdoid tumor, nongerminomatous germ cell tumor, pineoblastoma, primitive neuro-ectodermal tumor, glioneuronal tumor and group 3 medulloblastoma. Of those treated with RT, 13 (45%) received craniospinal irradiation (CSI) and 16 (55%) received focal RT. The median CSI dose was 23.4 Gy (IQR: 18-36; boost median 54 Gy [IQR: 53.7-55.8]) and focal RT dose was 50.4 Gy (IQR: 50.4-54.5). Compared to the focal RT group, patients treated with CSI were older (p=0.0499) and more likely to have metastatic disease (p=0.0004). For the complete cohort, at a median follow-up of 3.8 years, the 2-year rate of LC was 82% (95% CI: 70-96%), PFS was 63% (95% CI: 49-81%), and OS was 65% (95% CI: 51-82%). These rates did not differ significantly between patients treated with and without peri-transplant RT. Two cases of fatal myelopathy were observed after spinal cord doses within the highest tertile (41.4 CGE and 36 Gy); both cases occurred in patients who received RT before high-dose chemotherapy. CONCLUSION: Peri-transplant RT was used for high-risk disease. Oncologic outcomes after RT were encouraging. However, 2 cases of grade 5 myelopathy were observed. If used cautiously, RT may contribute to durable remission in patients at high risk of relapse.

EPID-10. Creation, use, and effectiveness of a primary provider education tool for timely pediatric CNS tumor diagnosis based on HeadSmart

BACKGROUND: Patients of minority race and ethnicity and lower socioeconomic status experience poorer survival of pediatric CNS tumors in the US. These disparities arise in part from differences in stage of disease at diagnosis, suggesting they could be mitigated by earlier diagnosis. HeadSmart is a campaign in the UK to increase awareness of pediatric CNS tumor symptoms among primary care practitioners and the public that has led to a significant decrease in time to diagnosis. METHODS: We created a 30-minute workshop, based on HeadSmart, to educate primary care providers on the presentation, common symptoms, work-up, and diagnosis of pediatric CNS tumors. We publicized the workshop throughout Colorado and delivered it via live webinar or online video recording. We collected demographic, specialty, and practice setting data from participants via optional survey. Participants could also take a 10-question, multiple-choice assessment of their knowledge on pediatric CNS tumor symptoms, work-up, and diagnosis before and after the workshop. RESULTS: We have now delivered the workshop to more than 400 providers in Colorado and the US. 39 providers participated in the survey; 19 completed both the pre- and post-workshop assessments. The mean pre-workshop score was 4.5 correct out of 10 (range 0-7); the mean post-workshop score was 5.4 (range 3-7) (unpaired t-test p=0.04). The mean improvement was 1.1 (paired t-test p=0.007). The majority of participants who completed the survey were pediatricians (n=30). Family practice (FP) physicians and pediatric/FP advance practice practitioners also participated. There was no significant difference in improvement for pediatricians vs. other providers. CONCLUSIONS: An educational tool based on the HeadSmart campaign was widely disseminated and is effective at increasing understanding of the timely diagnosis of pediatric CNS tumors among primary providers in Colorado. Further study, refinement, and dissemination have the potential to help mitigate disparities in pediatric CNS tumor outcomes.

IMMU-23. Novel gene-edited CAR-T cell therapy against Diffuse Intrinsic Pontine Glioma

BACKGROUND: We identified high expression of CD99 in DIPG tumors and developed a CAR using our newly identified single chain variable fragment (scFv) targeting CD99 incorporating a 4-1BB co-stimulatory domain. This CD99 CAR demonstrated the ability to dramatically shrink the established orthotopic DIPG tumor, however tumor recurrence remains an obstacle to cure, due to a loss of the CAR-T cells as they also express the target antigen, CD99 (fratricide). To overcome this obstacle, we modified these CAR-T by editing out CD99. METHODS: CD99 was knocked-out from the human T cells using CRISPR-cas9 gene-editing and subsequently transduced with our CD99 CAR-encoding virus, and isolated the pure population of CD99KO T-cells. These novel, gene-edited T-cells expressing CD99 CAR (“CD99KO CARs”) and the un-edited ones (“CD99 CAR”) were tested for tumor-lysis function when co-cultured with DIPG cells. DIPG tumor-bearing mice infused with a one-time dose of CD99KO CAR-T cells or CD99 CAR- or CD19 control CAR-T cells and were monitored for changes in the tumor burden. At the endpoint spleen and bone marrow were isolated to test for CAR+ cell persistence. RESULTS: The CD99KO CAR-T cells demonstrated effective tumor-lysis when co-cultured with DIPG cells. CD99KO CAR-T cells targeting CD99 showed complete clearance of DIPG tumor in orthotopic DIPG mouse models, and no tumor recurrence was seen well-beyond the time frame of expected tumor recurrence after treatment with un-edited CD99 CAR-T cells. There was an un-precedented increase in the xenograft survival, &gt; 200 days, in mice treated with CD99KO CARs and at which time point sustained persistence of CAR+ cells were evident in the animal spleen and bone marrow. CONCLUSIONS: We have generated a new and promising CAR-T cell therapy that is effective against DIPG with enhanced persistence in animal models which is critical for clinical translation.

Efficacy of tPBM on ADHD symptoms and Executive Function Deficits in Adults with high-functioning Autism Spectrum Disorder

Introduction

Executive function (EF) deficits are often associated with Autism Spectrum Disorder (ASD), even in the absence of Attention Deficit Hyperactivity Disorder (ADHD) diagnosis. To date, no approved medication treatments exist for EF deficits associated with ASD.

Objectives

To assess the efficacy of transcranial photobiomodulation (tPBM) on EF in adults with ASD.

Methods

Adults (18-59) with high-functioning (HF)-ASD received twice a week tPBM for 8 weeks in an open-label single group design. ASD and EF deficits were assessed by clinician-rated Clinical Global Impression Scale and patient-rated scales of Behavior Rating Inventory of Executive Function-Adult (BRIEF-A).

Results

Eleven participants were enrolled. Ten participants completed the study. Nine participants who completed the study had comorbid ADHD diagnosis. All 10 participants were included in efficacy analyses of EF deficits. Statistically significant improvements in executive function deficits were found in BRIEF-A total score and in subdomains of Inhibition, Emotional Control, Planning and Organization, Organization of Materials, Behavioral Regulation, Metacognitive Index and Global Executive Control. All participants were found to have mild to moderate improvement in their ADHD symptom severity per clinician rated CGIs. Statistically significant improvements in ADHD symptoms were noted in self-rated scales. No adverse events required changes in tPBM protocol.

Conclusions

tPBM is a safe and feasible treatment approach that has the potential to treat core features of ASD. Further research is necessary and warranted.

Disclosure

This work is funded by Alan and Lorraine Bressler Clinical and Research Program for Autism Spectrum Disorder and the MGH Pediatric Psychopharmacology Council Fund.

Absolute calibration of Fujifilm BAS-TR image plate response to laser driven protons up to 40 MeV

Image plates (IPs) are a popular detector in the field of laser driven ion acceleration, owing to their high dynamic range and reusability. An absolute calibration of these detectors to laser-driven protons in the routinely produced tens of MeV energy range is, therefore, essential. In this paper, the response of Fujifilm BAS-TR IPs to 1-40 MeV protons is calibrated by employing the detectors in high resolution Thomson parabola spectrometers in conjunction with a CR-39 nuclear track detector to determine absolute proton numbers. While CR-39 was placed in front of the image plate for lower energy protons, it was placed behind the image plate for energies above 10 MeV using suitable metal filters sandwiched between the image plate and CR-39 to select specific energies. The measured response agrees well with previously reported calibrations as well as standard models of IP response, providing, for the first time, an absolute calibration over a large range of proton energies of relevance to current experiments.

Rural residents' emotions, beliefs, and sources that influenced those beliefs regarding sex offender policies, practice, and the efficacy of treatment

Public perceptions regarding a sex offender's likelihood to reoffend and the efficacy of sex offender policies and practices is often inconsistent with the extant literature in academia. Thus, there is a critical need to better understand what influences those beliefs regarding sex offender policies and practices. We collected data from 284 residents from government defined rural counties and sought to examine: (1) the sources that were most influential in shaping their beliefs regarding sex offender policies and practices; (2) what characteristics the "influential sources" had; and (3) the residents' emotional response when they think about "sex offenders". The majority of participants were supportive of registration, community notification, and use of the polygraph. Further, the results suggest that "academics and peer review articles" rarely influence beliefs. Rather, "personal experiences" and the emotions "rage" and "sadness" (but not anger or disgust) may be important in influencing rural residents' beliefs regarding sex offender treatment, castration, execution, and misconceptions regarding juveniles with a sex offense. We conclude by discussing: (1) potential factors that may affect why academics are not perceived as influential sources; and (2) possibilities for how scientists can influence rural residents' beliefs by utilizing personal experiences and anecdotal information that may spark emotion.

Proximal humeral fracture-dislocations: which patterns can be reduced in the emergency department?

BACKGROUND

Shoulder fracture-dislocations can represent a challenging management scenario in the emergency department (ED) because of concern for the presence of occult fractures that may displace during a reduction attempt. The alternative, a closed reduction attempt in the operating room, has the benefit of full paralysis but requires additional resource utilization. There is limited guidance in the literature about the risks of an initial reduction attempt in the ED as a function of fracture pattern to help guide physicians with this decision.

METHODS

This was a retrospective case review of adult patients with shoulder dislocations and fracture-dislocations seen in the ED at a level 1 trauma center over a 10-year period. Imaging and medical records were reviewed to evaluate whether the reduction attempt was successful, unsuccessful without worsening, or unsuccessful with worsening alignment of any fractures, as well as the ultimate clinical outcome.

RESULTS

We identified 165 patients with fracture-dislocations and 484 patients with simple dislocations during the same period. Of the patients with fracture-dislocations, 103 had greater tuberosity fractures, 12 had nondisplaced surgical neck fractures, and 50 had displaced surgical neck fractures. None of the patients with simple dislocations had displacement during an ED reduction attempt, including 100 patients aged >65 years. Of the 103 patients with greater tuberosity fracture-dislocations, only 1 had displacement of a humeral shaft fracture during ED reduction. Displacement occurred in 6 of 8 patients with nondisplaced neck fractures who underwent an initial ED reduction attempt vs. 1 of 4 patients who underwent the initial reduction attempt in the operating room. ED reduction was attempted in 25 of the 50 displaced humeral neck fracture-dislocations and was successful in 10 of these (40%).

CONCLUSIONS

For patients with greater tuberosity fracture-dislocations, there is a low rate of displacement with a reduction attempt in the ED, but an ED reduction attempt in nondisplaced neck fractures is not recommended because of the high rate of displacement. For displaced neck fractures, closed reduction can be successful in select patients. Finally, these data confirm prior reports that closed reduction of simple shoulder dislocations in patients aged >65 years is safe in the ED.

Impact of Noninvasive Respiratory Support in Patients With COVID-19 Requiring V-V ECMO

The impact of the duration of noninvasive respiratory support (RS) including high-flow nasal cannula and noninvasive ventilation before the initiation of extracorporeal membrane oxygenation (ECMO) is unknown. We reviewed data of patients with coronavirus disease 2019 (COVID-19) treated with V-V ECMO at two high-volume tertiary care centers. Survival analysis was used to compare the effect of duration of RS on liberation from ECMO. A total of 78 patients required ECMO and the median duration of RS and invasive mechanical ventilation (IMV) before ECMO was 2 days (interquartile range [IQR]: 0, 6) and 2.5 days (IQR: 1, 5), respectively. The median duration of ECMO support was 24 days (IQR: 11, 73) and 59.0% (N = 46) remained alive at the time of censure. Patients that received RS for ≥3 days were significantly less likely to be liberated from ECMO (HR: 0.46; 95% CI: 0.26-0.83), IMV (HR: 0.42; 95% CI: 0.20-0.89) or be discharged from the hospital (HR: 0.52; 95% CI: 0.27-0.99) compared to patients that received RS for <3 days. There was no difference in hospital mortality between the groups (HR: 1.12; 95% CI: 0.56-2.26). These relationships persisted after adjustment for age, gender, and duration of IMV. Prolonged duration of RS before ECMO may result in lung injury and worse subsequent outcomes.

Severe ARDS Secondary to Legionella Pneumonia Requiring VV ECMO in the Setting of Newly Diagnosed Hairy Cell Leukemia

Venovenous (VV) extracorporeal membrane oxygenation (ECMO) for severe acute respiratory distress syndrome (ARDS) is initiated in patients with high mortality as a potential lifesaving intervention. Hematologic malignancy (HM) is considered a relative exclusion criterion by the Extracorporeal Life Support Organization (ELSO). This case examines the relative contraindication and presents a successful outcome. A healthy 59-year-old male presented with respiratory distress. On arrival his SpO₂ on room air was 82%, chest x-ray revealed a lobar infiltrate, complete blood count demonstrated severe leukopenia, and a peripheral blood smear demonstrated cytoplasmic inclusions concerning for hairy cells. He was intubated and decision was made to initiate VV-ECMO during hospital day (HD) 1. Cytometry later confirmed a diagnosis of hairy cell leukemia (HCL). A diagnosis of Legionella was confirmed on HD 5. Initial hospitalization was complicated by progression to complete bilateral lung involvement, pulmonary hemorrhage, recurrent tachyarrhythmias, hemodynamic instability, and acute renal failure. Respiratory status stabilized and eventually began to improve. On HD 27, he was decannulated and later discharged to rehabilitation. Four months later he received inpatient chemotherapy and is currently in full remission. This is a successful outcome in a patient with severe ARDS requiring VV-ECMO in the setting of newly diagnosed HCL. The 10-year survival for treated HCL is near 100%. Due to favorable prognosis, HCL should not be considered a relative contraindication to VV-ECMO. While HM remains a relative exclusion criterion by the ELSO, it is important to analyze each patient individually and make decisions based on evolving bodies of evidence.