Respiratory Failure Research Articles

Immune Checkpoint Inhibitor Myopathy: The Double-Edged Sword of Cancer Immunotherapy.

Immune checkpoint inhibitor (ICI) therapy has revolutionized the treatment of several malignancies, with improved survival. These monoclonal antibodies target immune checkpoints, including cytotoxic T-lymphocyte-associated protein 4 (ipilimumab and tremelimumab), programmed death 1 (nivolumab, pembrolizumab, cemiplimab, and dostarlimab), programmed death ligand 1 (atezolizumab, avelumab, and durvalumab), and lymphocyte activation gene 3 (relatlimab), and effectively augment the immune response against tumor cells. Releasing the brakes on the immune system has consequences, however, in the form of immune-related adverse events (irAEs), which may affect any organ. Neurologic irAEs represent 1%-3% of all irAEs, with immune-mediated myopathy (ICI myopathy) being the most common manifestation. Recent large patient series and systematic reviews have established the key features and highlighted new insights into ICI myopathy. ICI myopathy is characterized by an acute or subacute onset of oculobulbar and/or proximal limb weakness, with or without associated respiratory insufficiency and myocarditis. Creatine kinase elevation is common. Oculobulbar presentations with or without respiratory failure may be misattributed to neuromuscular junction disorders, particularly because acetylcholine receptor antibodies are present in up to 40% of patients; however, an electrodiagnostic evidence of a defect of neuromuscular transmission is often absent even in patients with severe weakness, highlighting that the myopathic process is the driving force behind these presentations. Muscle histopathology commonly demonstrates a unique signature of multifocal clusters of necrotic and regenerating fibers, differentiating ICI myopathy from other autoimmune myopathies. Transcriptomic analysis has uncovered distinct subgroups within ICI myopathy, revealing varying degrees of type 1 and type 2 interferon pathway activation alongside notable upregulation of the interleukin (IL)-6 pathway in affected muscle tissue. This discovery presents a promising avenue for intervention through the use of therapies that suppress the interferon pathway and target IL-6 or its receptor. Despite clinical improvements with immunomodulatory therapy, with corticosteroids the mainstay of treatment, mortality remains high, particularly in those with associated myocarditis or respiratory failure requiring intubation, where mortality occurs in up to 50%. ICI withdrawal can lead to cancer progression and death, highlighting a need for improved approaches to ICI rechallenge, performed in limited patients with variable success to date.

Deep learning model for detection acute cardiogenic pulmonary edema in cases of preeclampsia

<span lang="EN-US">The physiological changes during the pregnancy period increase the risk of developing pulmonary edema and acute respiratory failure. This condition falls under critical medical emergencies associated with maternal mortality. This study utilized a convolutional neural networks (CNN) architectural model employing chest Xray dataset images. CNN utilizes the convolution process by moving a convolutional kernel of a certain size across an image, allowing the computer to derive new representative information from the multiplication of portions of the image with the utilized filter.</span><span lang="EN-US">To simplify, the vanishing gradient issue occurs when information dissipates before reaching its destination due to the lengthy path between input and output layers. This study was developed model for detection acute cardiogenic pulmonary Edema in pre-eclampsia cases using chest Xray images, implemented using PyTorch, Keras, and MxNet. The validated model achieved its optimum with accuracy 90.65% and binary cross-entropy loss (BCELoss) value of 0.4538. It exhibited an improved sensitivity value of 83.514% using a 5% dataset and a specificity value of 57.273%. This indicates an increase in sensitivity value by 83.514% using a 5% data set and a specificity value of 57.273%. The research results demonstrate an improvement in accuracy compared to several similar studies that also utilized CNN models.</span>

Yohimbine treatment improves pulmonary fibrosis by attenuating the inflammation and oxidative stress via modulating the MAPK pathway

Idiopathic pulmonary fibrosis (IPF) is a devastating interstitial lung disorder characterized by the accumulation of extracellular matrix and collagen, resulting in significant parenchymal scarring and respiratory failure that leads to mortality. Yohimbine (YBH) is an α-2 adrenergic receptor antagonist with anti-oxidant and anti-inflammatory properties. In the current study, we aimed to investigate the anti-inflammatory, anti-oxidant and anti-fibrotic activity of YBH against LPS/TGF-β-induced differentiation in BEAS-2B/LL29 cells and bleomycin (BLMN) induced pulmonary fibrosis model in rats. Network pharmacology, gene expression, Western-blot analysis, immune-cytochemistry/immunohistochemistry, lung function and histology techniques were used to assess the fibrotic marker expression/levels in cells or rat lung tissues. YBH treatment significantly attenuated the LPS-induced pro-inflammatory (identified through a network-pharmacology approach) and oxidative stress markers expression in lung epithelial cells. TGF-β stimulation significantly elevated the fibrotic cascade of markers and treatment with YBH attenuated these markers’ expression/levels. Intra-tracheal administration of BLMN caused a significant elevation of various inflammatory/oxidative stress and fibrotic markers expression in lung tissues and treatment with YBH significantly mitigated the same. Ashcroft score analysis revealed that BLMN exhibited severe distortion of the lungs, elevation of thickness of the alveolar walls and accumulation of collagen in tissues, further treatment with YBH significantly suppressed these events and improved the lung architecture. Lung functional parameters demonstrated that BLMN-induced stiffness and resistance were reduced considerably upon YBH treatment and restored lung function dose-dependently. Overall, this study reveals that YBH treatment significantly attenuated the BLMN-induced fibrosis by regulating the MAPK pathway and provided insightful information for progressing towards translational outcomes.

A Novel MYH14 Variant Presenting as a New Phenotype of MYH14-Associated Neuromuscular Disorders—Clinicohistologic Findings and Review of the Literature

Abstract Background: Pathogenic variants in the nonmuscle myosin, MYH14, have been associated with several pathologic conditions including a complex phenotype with peripheral neuropathy, myopathy, hoarseness, and hearing loss. Since its first description in a large Korean kindred, this rare neuromuscular disorder has further been characterized in 1 American and 1 Canadian pedigree. Case presentation: Here, we describe a German patient with atypical MYH14-related neuromuscular disorder. The clinical phenotype included signs of a distal myopathy with early respiratory involvement and a prominent hoarseness and peripheral neuropathy. In contrast to previous reports, no relevant deafness was identified. Muscle biopsy indicated a vacuolated myopathy with excessive autophagy, whereas histology of the sural nerve showed signs of a mixed axonal-demyelinating neuropathy. Next-generation sequencing revealed a loss-of-function variant not identified so far in the MYH14 gene (c.4510del, p.[Arg1504Glyfs*10]). Because of rapid disease progression with respiratory failure, the patient died at the age of 52. Conclusions: We present a novel MYH14 variant resulting in a severe and rapidly progressive MYH14-associated phenotype with predominantly distal myopathy, early respiratory failure, dysphagia, hoarseness, and peripheral neuropathy, without hearing loss. This case expands the clinical spectrum of MYH14-related neuromuscular disorders by providing a new clinical phenotype and disease course and histopathologic features.

Clinical Value of HACOR Score in Predicting High Flow Nasal Oxygen Therapy Failure in Hypoxemic Patients

Objective: To assess the sensitivity of the HACOR score in successfully predicting high flow nasal oxygen (HFNO) failure in acute hypoxemic patients. Methodology: A Prospective observational study was conducted at Critical care departments of Combined Military Hospital, Lahore, Okara and Rahim Yar Khan from Jan-Dec 2023. A total of 390 patients diagnosed as having acute hypoxemic respiratory failure (PaO2<60 mm Hg and/or pH <7.35) were selected and started on HFNO therapy. Primary variables studied were the sensitivity and specificity of the HACOR score in predicting HFNO failure after the first hour of therapy . Secondary variables studied compared the improvement in HACOR parameters after 1-hour of HFNO therapy in those patients who has success with HFNO. Results: While assessing the power of the HACOR score in predicting failure of HFNO therapy with scores obtained after one hour, the area under the curve showed a value of 0.88 showing a good predictive power of failure for the test. A cut off value >6 was able to predict failure with a sensitivity of 85.9%, specificity of 93.8% with a positive and negative predictive value of 96.6% and 76.4% respectively Conclusion: We conclude the HACOR score as a useful method with a cut-off value of more than 6 predicting a failure rate to HFNO to be > 86% after 1 hour of therapy. Key Words: Failure, HACOR, HFNO, Hypoxemic

Novel AIFM1 Variant in 2 Siblings With Sensorineural Hearing Loss and Cerebellar Ataxia.

Apoptosis-inducing factor mitochondria-associated 1 (AIFM1) gene encodes a mitochondrial flavoprotein that mediates caspase-independent programmed cell death. We report a novel AIFM1 variant in 2 siblings with early-onset hearing loss and progressive cerebellar ataxia. We evaluated the clinical features, brain MRI scans, EMG studies, and whole genome sequencing (WGS). Sibling A is a 19-year-old man with auditory neuropathy at age 15 years, who subsequently developed optic atrophy, progressive gait and limb ataxia, peripheral neuropathy, and ambulation with cane by age 17 years. Brain MRI was normal. Sibling B is a 13-year-old boy with auditory neuropathy diagnosed at 7 and gait instability at 13, with rapid development of peripheral neuropathy, cerebellar ataxia, muscle weakness and atrophy needing wheelchair for mobility, and neuromuscular respiratory failure requiring noninvasive ventilation. Brain MRI showed mild cerebellar atrophy. Initial EMGs showed axonal neuropathy in both and diffuse chronic and active anterior horn cell disorder later in Sibling B. WGS revealed an X-linked, maternally inherited novel AIFM1 variant (c.1299C>G p. Ile433Met). AIFM1 variants should be considered in patients with hereditary cerebellar ataxia and auditory neuropathy. We highlight a novel AIFM1 variant and its phenotypic intrafamilial variability expanding the knowledge of the genetic spectrum of AIFM1-related diseases.

Benefit of Expedited Time to Hip Fracture Surgery Differs Based on Patient Risk Profile.

To identify which hip fracture patients benefit the most from operative repair within 24 hours of Emergency Department (ED) presentation based on patient risk stratification. Design: Retrospective Cohort. Academic Medical Center. Patients operatively treated for an AO/OTA 31A, 31B, or 32A hip fracture. Each patient was placed into an "individualized risk quartile" (IRQ) using a validated risk stratification tool (The Score for Trauma Triage in the Geriatric and Middle-Aged [STTGMA], a tool proven to predict inpatient mortality in trauma patients). Patients were risk stratified into minimal-, low-, moderate-, and high-risk IRQ's. In each cohort, patients were separated into three groups based on their time from ED arrival to surgery (< 24 hours, > 24 hours and < 48 hours, and > 48 hours). Each of these 12 groups was analyzed for complications (minor inpatient complications included acute kidney injury, urinary tract infection, decubitus ulcer, and acute blood loss anemia, while major inpatient complications included sepsis or septic shock, pneumonia, acute respiratory failure, stroke, myocardial infarction, cardiac arrest, and deep vein thrombosis or pulmonary embolism), mortality rates, and hospital quality measures (length of stay and readmission rates). The results were compared across cohorts. A total of 2472 patients were identified: the mean age of the cohort was 80.6 ± 10.3 and was predominantly female (69%) and white (71%). The data demonstrated improved outcomes (complications, mortality rates, hospital quality measures) across all patients (non-risk stratified) for surgery within 24 hours compared to surgery between 24 hours and 48 hours and surgery greater than 48 hours (all outcomes p<0.050). However, these effects were not evenly distributed among the IRQ's. In the IRQ4 cohort, major complication rates progressed from 20% to 25% to 34% as a function of time to surgery (p=0.007). IRQ1 did not demonstrate similar results (p=0.756), with the rates essentially static across surgery time points (3% to 2% to 4%). A similar trend was seen when analyzing mortality at 1-year for highest risk patients, with similar 1-year mortality rates across operating room windows of IRQs 1-3 (IRQ1: p=0.061, IRQ2: p=0.259, IRQ3: p=0.524), but increased in IRQ4 with increasing time to surgery (21% vs 33% vs 33%, p=0.006). This study demonstrates a differential impact of expedited time to surgery on patients when stratified by risk profile. The lowest risk hip fracture patients do not fare worse if operated on within 48 hours as compared to 24 hours. III.

Phosphatidylethanol measures in patients with severe COVID-19-associated respiratory failure identify a subset with alcohol misuse.

Clinical trials in patients with COVID-19 have exclusively used self- or proxy-reporting to characterize alcohol consumption. The aim of this study was to measure an objective biomarker of recent alcohol use in patients hospitalized with severe COVID-19-associated respiratory failure who were enrolled in an investigational clinical trial to determine the prevalence of alcohol misuse, and to explore the relationship of alcohol use with outcomes. We conducted a substudy of patients enrolled in the multicenter, phase 2, adaptive platform design, Investigation of Serial Studies to Predict Your Therapeutic Response with Imaging And molecular Analysis in COVID-19 trial (ClinicalTrials.gov: NCT04488081), conducted at 20 hospital systems across the United States. Three hundred and fifty-five patients with available red blood cell (RBC) samples and 60-day follow-up assessments were included. RBCs were utilized to measure phosphatidylethanol (PEth). Prespecified thresholds of PEth were utilized to stratify patients into groups: low/no alcohol use (PEth < 20 ng/mL), significant alcohol use (PEth 20-200 ng/mL), and heavy alcohol use (PEth ≥ 200 ng/mL). In this cohort, 17% of patients met criteria for significant alcohol use, while 4% met criteria for heavy alcohol use. Alcohol misuse was associated with diminished odds for home discharge, though this finding did not achieve statistical significance. In a cohort of patients with severe COVID-19 enrolled in a clinical trial, alcohol consumption of two or more standard drinks per day was present among 21%, approximating the proportion of patients with diabetes, and raising the possibility that alcohol consumption alters risk for severe viral pneumonia. Undetected alcohol misuse among clinical trial participants has the potential to influence study outcomes or contribute to adverse events.

PHRENIC NERVE RECONSTRUCTION WITH SHORT-TERM DIAPHRAGM PACING CORRECTS DIAPHRAGM PARALYSIS DUE TO INTRATHORACIC NERVE INJURY.

Symptomatic diaphragm paralysis and subsequent pulmonary debilitation has been shown to occur following phrenic nerve injury within the thoracic cavity. In this study, we investigate the effectiveness of intrathoracic reconstruction of the phrenic nerve combined with short-term diaphragm pacing in restoring diaphragm function. A retrospective review of 34 consecutive patients who underwent intrathoracic phrenic nerve reconstruction and diaphragm pacing for symptomatic diaphragm paralysis was performed. Inclusion criteria included confirmation of diaphragm paralysis on chest fluoroscopy, BMI <40, Age <75, and presence of functional motor units on EMG testing. Surgical treatment consisted of intrathoracic phrenic nerve reconstruction with simultaneous implantation of a diaphragm pacemaker. 34 patients met inclusion criteria, including: 23 males and 11 females with an average age of 46 and average BMI of 28.5 kg/m2. Thirty patients (88%) reported improvement in respiratory function. FVC and FEV1 values improved by 15% (p=0.02) and 14% (p=0.049), respectively. A 375% increase in diaphragm motor amplitude was observed, from 0.04mV to 0.19mV (p=0.02). Radiographic improvement in resting diaphragm position and contraction was demonstrated in 71% of patients. Complications included pacemaker site infection (5%), cardiac arrythmia (5%), and asymptomatic abdominal bulge (3%). Intrathoracic phrenic nerve reconstruction with short-term diaphragm pacing is a safe and effective surgical treatment that improves diaphragm function and alleviates symptoms of respiratory insufficiency in patients with diaphragmatic paralysis following intrathoracic phrenic nerve injury. This approach should be considered as part of the treatment algorithm for this patient population.

Antipsychotics and Risk of Acute Respiratory Failure in U.S. Medicare Beneficiaries with Chronic Obstructive Pulmonary Disease.

Acute respiratory failure (ARF) associated with antipsychotic use has been documented through case reports and population-based studies. To assess whether the recent use of antipsychotics is associated with an increased risk of ARF in U.S. Medicare beneficiaries with chronic obstructive pulmonary disease. Case-crossover study conducted among U.S. Fee-for-Service Medicare beneficiaries with chronic obstructive pulmonary disease hospitalized with ARF, from January 1, 2007, through December 31, 2019. Oral antipsychotics. Adjusted odds ratios (aOR) and 95% confidence intervals (CI) for ARF requiring invasive mechanical ventilation associated with the use of antipsychotics in the case period (days -14 to -1) compared to the control period (days -75 to -88). We identified 145,018 cases (mean age 69.4years, 57.2% female). Of these, 2,003 had antipsychotic use only during the case period and 1,728 only during the control period. The aOR of ARF within 14days after antipsychotic use was 1.13 (95% CI, 1.06, 1.20). The risk increased with increasing age, being statistically significant in patients ages 75-84years (aOR: 1.37 [95% CI, 1.17, 1.60]) and 85 + years (aOR: 1.50 [95% CI, 1.20, 1.89]), but not in beneficiaries under 75years of age (aOR 18-49years: 1.01 [95% CI, 0.85, 1.20]; 50-64years: 1.03 [95% CI, 0.92, 1.15]; 65-74years: 1.12 [95% CI, 0.98, 1.27]). Recent antipsychotic use by Medicare beneficiaries with chronic obstructive pulmonary disease was associated with an increased risk of ARF in those aged 75years and older.

Clinical Impact of Admission Day on Outcomes in Acutely Decompensated Aortic Stenosis: A Nationwide Analysis

Background/Objectives: Aortic stenosis (AS) is a critical valvular heart disease associated with significant morbidity and mortality if not managed promptly. Previous studies have highlighted the “weekend effect”, where the day of admission impacts outcomes in various cardiac conditions. This study evaluates the impact of weekend versus weekday admissions on outcomes in patients admitted with acutely decompensated aortic stenosis. Methods: We conducted a retrospective cohort study using the National Inpatient Sample database, focusing on patients emergently admitted with decompensated aortic stenosis. Patient outcomes were compared between those admitted on weekends (midnight Friday to midnight Sunday) and weekdays. Results: Among 94,320 patients included, 4537 (4.81%) were admitted on weekends. Weekend admissions were associated with significantly higher mortality (aOR 1.86; 95% CI 1.27–2.74) and longer hospital stays (mean increase 3.18 days; p &lt; 0.001) compared to weekday admissions. Complication rates were also higher on weekends, including cardiogenic shock (aOR 2.1; 95% CI 1.54–2.87; p &lt; 0.001), acute kidney injury (aOR 2.48; 95% CI 2.09–2.94; p &lt; 0.001), and acute respiratory failure (aOR 2.88; 95% CI 2.38–3.49; p &lt; 0.001). Additionally, weekend admissions had lower rates of transcatheter aortic valve replacement (TAVR) (aOR 0.49; 95% CI 0.40–0.62; p &lt; 0.01) than weekday admissions. Conclusions: Patients with aortic stenosis admitted on weekends face significantly higher mortality, extended hospital stays, and increased complication rates compared to weekday admissions. Transcatheter aortic valve replacement (TAVR) rates were also lower for patients admitted on weekends. The “weekend effect” markedly influences outcomes, underscoring the need for hospital and administrative strategies to mitigate these adverse effects. Implementing standardized protocols and optimizing resource allocation during weekends could potentially reduce mortality and improve patient outcomes, offering a path to more equitable healthcare delivery.

Mitochondrial dysfunction in Parkinson's disease.

The exact cause of nigral cell death in Parkinson's disease (PD) is still unknown. However, research on MPTP-induced experimental parkinsonism has significantly advanced our understanding. In this model, it is widely accepted that mitochondrial respiratory failure is the primary mechanism of cell death. Studies have shown that a toxic metabolite of MPTP inhibits Complex I and alpha-ketoglutarate dehydrogenase activities in mitochondria. Since then, many research groups have focused on mitochondrial dysfunction in PD, identifying deficiencies in Complex I or III in PD patients' brains, skeletal muscle, and platelets. There is some debate about the decline in mitochondrial function in peripheral organs. However, since α-synuclein, the main component protein of Lewy bodies, accumulates in peripheral organs, it is reasonable to consider PD a systemic disease. Additionally, mutant mitochondrial DNA with a 4,977 base pair deletion has been found in the brains of PD patients, suggesting that age-related accumulation of deleted mtDNA is accelerated in the striatum and may contribute to the pathophysiology of PD. While the cause of PD remains unknown, mitochondrial dysfunction is undoubtedly a factor in cell death in PD. In addition, the causative gene for familial PD, parkin (now PRKN), and PTEN-induced putative kinase 1 (PINK1), both gene products are also involved in mitochondrial quality control. Moreover, we have successfully isolated and identified CHCHD2, which is involved in the mitochondrial electron transfer system. There is no doubt that mitochondrial dysfunction contributes to cell death in PD.

Sudden Death in a Rare Case Due to Tracheo-Innominate Artery Fistula

Background: Tracheostomy is an essential procedure in cases of respiratory failure in patients requiring long-term ventilation or showing airway obstruction. Tracheostomy has both immediate and long-term complications. Among these, tracheo-innominate fistula is an emergency that is a rare long-term complication. When it occurs, this event is catastrophic for the patient’s life, as it causes death in a very short time due to hemorrhagic shock. Therefore, it is essential to identify risk factors to prevent these cases. Methods: We describe the autopsy findings in a case of death from tracheo-innominate fistula of a patient admitted to the Intensive Care Unit. Results: The autopsy demonstrated, in addition to the large fistula, the coexistence of a malformation of the cervical spine with a significant increase in the diameter of the neck. Therefore, we emphasize in this case the importance of evaluating risk factors in subjects with tracheostomy by highlighting the role of anatomy and the size of the neck as potential predictable risks. Conclusions: The work retraces through a review the pathogenesis of this rare complication and emphasizes the need for early diagnosis and prevention of the risk of death with specific risk scales.

Clinical and biological advances of critical complications in acute myeloid leukemia.

Managing acute myeloid leukemia (AML) and its critical complications requires understanding the complex interplay between disease biology, treatment strategies, and patient characteristics. Complications like sepsis, acute respiratory failure (ARF), hyperleukocytosis, coagulopathy, tumor lysis syndrome (TLS) and central nervous system (CNS) involvement present unique challenges needing precise evaluation and tailored interventions. Venetoclax-induced TLS and differentiation syndrome (DS) from IDH1/IDH2 or menin inhibitors highlight the need for ongoing research and innovative approaches. As the microbiological landscape evolves and new therapeutic agents emerge, adapting strategies to mitigate harmful pharmacological interactions is crucial. Advances in understanding the genetic profiles of patients with hyperleukocytosis contribute to better-targeted therapeutic strategies. Effective AML management relies on collaborative efforts from hematologists, specialized services, and intensive care units (ICUs). This review analyzes recent data on critical AML complications, identifies areas for further investigation, and proposes ways to advance clinical research and enhance patient care strategies.

Prediction of respiratory failure and prolonged mechanical ventilation in Guillain-Barré syndrome: A prospective cohort study in Bangladesh.

The aim of this study is to validate and perform a region-specific adjustment of the Erasmus GBS Respiratory Insufficiency Score (EGRIS) and identify potential predictors of prolonged mechanical ventilation (PMV) among Guillain-Barré syndrome (GBS) patients from Bangladesh. We enrolled GBS patients from four prospective observational cohort studies conducted in Bangladesh. Accuracy of EGRIS to predict the requirement of MV in <7 days of study entry was evaluated. Model performance was assessed by discrimination (ability of the model to differentiate between patients who needed MV or not) and calibration (accuracy of absolute risk estimates). PMV was defined as duration of MV >14 days. Potential predictors for PMV were evaluated by Cox regression. A total of 594 GBS patients aged ≥6 years old were enrolled; of whom 541 patients had complete EGRIS data prior to MV and were included in validation analysis. EGRIS correctly distinguished between patients requiring MV or not in 81% pairs (AUC = 0.81). EGRIS overestimated the probability of MV than the observed probability (41% vs. 20%) which was resolved by updating of the model intercept. Inability to flex hip at day 7 of start of MV was the strongest predictor for PMV with predicted probabilities of 82%. EGRIS accurately predicts the need for MV in GBS patients from Bangladesh. This study developed a region-specific version of EGRIS and identified predictors of PMV. These findings can assist clinicians to identify patients at high risk of developing respiratory failure and requiring PMV to ensure timely intubation and tracheostomy of the patients in low resource settings.

Analysis of the Generation and Spatiotemporal Distributions of Dust During Tunnel Construction

The dust generated during tunnel construction poses serious health risks to workers, as it not only causes respiratory obstruction but also leads to pneumoconiosis and respiratory failure after prolonged exposure. However, most existing studies focus on specific construction stages or particular particle sizes and often assume an ideal airflow, neglecting the complex flow fields, vortex effects, and dust composition variations at different stages in tunnel and mine construction. This study systematically analyzes the spatiotemporal distribution characteristics of dust at various stages of tunnel construction and proposes targeted prevention and control strategies. On the basis of measured data from three construction stages—the working face, initial support, and secondary lining stages—and SPSS 27 statistical analysis, a dynamic analysis was conducted on the concentration and distribution patterns of total suspended particulates (TSPs) and particulate matter of different sizes (PM10, PM4, PM2.5, and PM1). The results show that coarse particles dominate during the working face stage, whereas fine particles gradually accumulate during the initial support and secondary lining stages. Finally, this work establishes a dust concentration–excavation time/tunnel depth equation and proposes targeted dust control measures. These findings offer important practical value for enhancing construction safety and air quality.

High flow nasal cannula and low level continuous positive airway pressure have different physiological effects during de novo acute hypoxemic respiratory failure

BackgroundLarge tidal volumes during de novo acute hypoxemic respiratory failure (AHRF) may promote patient self-inflicted lung injury. Tidal volume assessment under high flow nasal cannula (HFNC) is not routinely feasible at the bedside. Our objective was to determine whether tidal volume during low-level continuous positive airway pressure (CPAP) could predict tidal volume during HFNC and to compare the physiological effects of HFNC and low-level CPAP.MethodsProspective, single-center study including 29 de novo AHRF patients treated with HFNC (50 to 60 L.min− 1). Patients were monitored using electrical impedance tomography during HFNC then CPAP at 4 cmH2O. Tidal volume during HFNC was calculated based on tidal impedance variation. The ability of tidal volume under low-level CPAP to predict tidal volume under HFNC was explored using Bland-Altman analysis. CPAP and HFNC were compared in terms of tidal volume, minute ventilation, respiratory comfort, dyspnea, oxygenation, ventilation distribution, end-expiratory lung volume, thoraco-abdominal asynchrony and recruitment.ResultsUnder HFNC, patients had a tidal volume of 6.6 (5.9–8.7) mL.kg− 1 PBW. 20 (69%) patients exhibited a tidal volume between 4 and 8 mL.kg− 1 PBW, while in 5 (17%) patients it exceeded 9 mL.kg− 1 PBW. Tidal volume under CPAP was higher (9.4 (8.3–11) mL.kg− 1 PBW, p < 0.001). Tidal volumes under CPAP and under HFNC were modestly correlated (Spearman r = 0.50, p = 0.005). Bland-Altman analysis showed a bias of 2.4 mL.kg− 1, with limits of agreement ranging from − 1.1 mL.kg− 1to 5.9 mL.kg− 1. Nevertheless, a larger (> 11.5 mL.kg− 1 PBW ) tidal volume under low-level CPAP predicted a larger (> 9 mL.kg− 1 PBW ) tidal volume under HFNC with 80% sensitivity and 96% specificity. Low-level CPAP was associated with increased minute ventilation, end-expiratory lung volume, and oxygenation as compared to HFNC. It decreased signs of respiratory distress in the most severe patients but was associated with lower comfort compared to HFNC.ConclusionAmong ICU patients with de novo AHRF, tidal volume under HFNC was mostly protective. Tidal volume during CPAP at 4 cmH2O did not predict tidal volume during HFNC. Such low-level CPAP was associated with increased tidal volume, minute ventilation, end-expiratory volume, and oxygenation.Trial registrationClinicalTrials.gov ID NCT03919331. Registration date: 2019-03-26.

Non-intensive care unit feasibility for ambulatory veno-venous extracorporeal membrane oxygenation patients.

Veno-venous extracorporeal membrane oxygenation has increasingly been utilized to support patients in respiratory failure as a bridge to recovery or lung transplantation. As patients progress from cannulation to recovery or transplantation, it has been shown that physical therapy and ambulation are possible and beneficial for patient outcomes. We sought to evaluate the feasibility of managing these ambulatory VV-ECMO patients in a non-ICU setting by conducting a single-center, retrospective cohort study to characterize the daily data collection (i.e., CXRs, blood draws, etc.) and ICU and ECMO interventions and events (i.e., oxygenator/cannula exchange, sweep or flow adjustments, etc.). A total of 28 ECMO runs from patients ≥18 years of age who ambulated ≥100 feet while on VV ECMO between 2014 and 2020 were included for analysis. Patients were supported on ECMO a median of 33 [18-79.5] days with a mean of 4.0 (3.8,4.1) data collections per day. There was a mean of 1.1 (1.0,1.2) anticoagulation changes, 1.5 (1.4,1.6) ECMO interventions, and 0.40 (0.34,0.46) ICU interventions per day. There were very few instances of cannula repositioning or oxygenator exchanges - 0.05 (CI 0.04, 0.06) per day. Our data suggests that ambulatory VV-ECMO patients may tolerate less than ICU level of care and may even progress to outpatient management as ECMO technology continues to advance.

A Clinical Case of a 10-Month-Old Child with Severe COVID-19 with Multisystem Inflammatory Syndrome Ended Fatally

Abstract At the beginning of the COVID-19 pandemic, it was assumed that children were at low risk of infection and that their infection was milder than adults. With an increase in the number of pediatric cases of SARS-CoV-2 infection associated with manifestations of hyperinflammation, the condition of multisystem inflammatory syndrome in children (MIS-C) was defined. We present a clinical case of a 10-month-old male child hospitalized in the Clinic of Infectious Diseases at University Hospital in Stara Zagora, Bulgaria, with a COVID-19. The patient had a number of co-morbidities, including protein-calorie malnutrition, chronic respiratory failure and bronchopulmonary dysplasia. During the hospital stay, he had an active diarrhea syndrome, with evidence of pneumonia and respiratory failure. In the clinical course, a progressive worsening of the condition with signs of multiple organ failure, increase in inflammatory markers and deterioration of coagulation indicators were observed. Placement in the ICU and the inclusion of artificial pulmonary ventilation were required, but after an 18-day hospital stay, the patient died. In conclusion, this was an acute case of COVID-19 in an infant that started with respiratory and gastrointestinal manifestations that progressed to MIS-C with multiple organ failure leading to death. We believe that the reason for this is the compromised immune status in connection with the highly damaged premorbid terrain and young age.

Battlefield mechanical ventilation and extracorporeal membrane oxygenation: A scoping review.

Casualties of military conflicts suffer a multitude of injuries, and recent research has documented a significant number develop acute respiratory distress syndrome (ARDS). The present study undertakes a scoping review of research on the treatment of ARDS in combat casualties near the battlefield. We review the extent of the current ARDS care, from intubation and mechanical ventilation (MV) to the use of extracorporeal membrane oxygenation (ECMO), and how the respective echelons of care across the Military Health System (MHS) are involved in the care of these patients. Online databases were used to identify article published 1988-2022, from which we selected 112 publications from various countries including the USA, UK, Germany, Italy, and India that used military relevant keywords (i.e., battlefield, combat, deployed, military trauma), in the titles or abstract in conjunction with the MeSH descriptors for battlefield respiratory failure, and MV or ECMO. Mechanical ventilation and ECMO have clearly moved forward with progressions in technologies and now are routinely used and are well documented in the prehospital setting and during aeromedical transport. Overview of the MHS and descriptive analysis of battlefield casualties are well represented in the literature. There are multiple publications on airway management on the battlefield and innumerable regarding the somewhat comparable civilian prehospital trauma airway management. While there is an abundance of publications on MV in the prehospital and combat environments, there are few case examples of the use of ECMO on the battlefield. Although MV may be required for many combat casualties, airway management failure remains the second leading cause of preventable death on the battlefield.