Respiratory Oxygen Research Articles

Factors of late respiratory support or oxygen weaning in infants with bronchopulmonary dysplasia.

Bronchopulmonary dysplasia (BPD) is the most common complication in preterm infants. This study aimed at identifying factors associated with early or with late or weaning failure from respiratory support or oxygen (O2) in preterm infants with BPD requiring respiratory support or O2 therapy after discharge from the neonatal intensive care unit (NICU). This retrospective study was conducted in the NICU of a tertiary hospital, in infants born before 32 weeks of gestation between 2012 and 2021, and discharged from the NICU with a respiratory support (tracheostomy [TT], invasive ventilation [IV], Non-IV [NIV], continuous positive airway pressure [CPAP], high flow nasal canula [HFNC]) or O2 therapy for BPD. Univariate and multivariate analyses were performed to identify factors associated with early weaning (before 6 months postmenstrual age [PMA]) or late (after 6 months PMA) and weaning failure. Among the 53 infants included (2% TT, 2% IV, 11% NIV, 25% CPAP or HFNC, 60% O2 at NICU discharge), 23 (43%) were weaned from respiratory support or O2 before 6 months PMA and 39 (73%) before 12 months PMA. IV duration during NICU stay and postnatal steroid treatment were identified as factors associated with a late or weaning failure (OR 1.03, p = .04 and OR 4.11, p = .023, respectively). In this study, nearly half of preterm infants with severe BPD were weaned from respiratory support or O2 before 6 months PMA. IV duration and postnatal steroid treatment during NICU stay were associated with a late or weaning failure.

Feasibility of snapshot testing using wearable sensors to detect cardiorespiratory illness (COVID infection in India).

The COVID-19 pandemic has challenged the current paradigm of clinical and community-based disease detection. We present a multimodal wearable sensor system paired with a two-minute, movement-based activity sequence that successfully captures a snapshot of physiological data (including cardiac, respiratory, temperature, and percent oxygen saturation). We conducted a large, multi-site trial of this technology across India from June 2021 to April 2022 amidst the COVID-19 pandemic (Clinical trial registry name: International Validation of Wearable Sensor to Monitor COVID-19 Like Signs and Symptoms; NCT05334680; initial release: 04/15/2022). An Extreme Gradient Boosting algorithm was trained to discriminate between COVID-19 infected individuals (n = 295) and COVID-19 negative healthy controls (n = 172) and achieved an F1-Score of 0.80 (95% CI = [0.79, 0.81]). SHAP values were mapped to visualize feature importance and directionality, yielding engineered features from core temperature, cough, and lung sounds as highly important. The results demonstrated potential for data-driven wearable sensor technology for remote preliminary screening, highlighting a fundamental pivot from continuous to snapshot monitoring of cardiorespiratory illnesses.

Long-Term Mental Health Outcomes of Bronchopulmonary Dysplasia in Neonates: An 18-Year National Cohort Study.

To evaluate the association between neonatal bronchopulmonary dysplasia and the subsequent development of mental health conditions in children and adolescents. This was a retrospective cohort study, utilizing data from individuals born in South Korea between 2002 and 2005 and followed up until 2021, using the National Health Insurance Database. The cohort included 1,893,314 participants born during that period, with 927 diagnosed with bronchopulmonary dysplasia during the neonatal period (the exposed cohort). They were matched 1:10 with 9,270 unexposed individuals (the unexposed cohort) based on key demographic factors. The median age at the first mental health disorder diagnosis was 9 years (interquartile range, 5-15 years), with 5,698 individuals (55.9%) being male. During an average follow-up of 15.2 years, the incidence rate was 481/10,000 person-years in the exposed and 138/10,000 person-years in the unexposed cohort. By the age of 18 years, the cumulative incidence in the exposed cohort was 54% (95% confidence interval [CI]; 50%-57%), with an adjusted hazard ratio of 3.18 (95% CI; 2.81-3.60) compared with the unexposed cohort, and adjusted hazard ratios for early- and late-onset mental health disorders of 4.48 (95% CI; 3.84-5.22) and 1.89 (95% CI; 1.61-2.22), respectively. Sensitivity analyses confirmed these findings, and a subgroup analysis revealed a higher risk among individuals with bronchopulmonary dysplasia who required prolonged respiratory support or oxygen. Half of children with bronchopulmonary dysplasia in our cohort developed mental health disorders by the age of 18 years, emphasizing the need for interventions and support for such individuals.

Evaluation of physiological variables determining time to mortality after stroke-associated pneumonia.

Introduction Stroke-associated pneumonia (SAP) frequently complicates stroke and is associated with significant mortality. Clinicians often use physiological variables within the National Early Warning Score (NEWS) when diagnosing and prescribing antibiotics for SAP, but little is known of its association with mortality. We investigated the relationship of the NEWS 2 score and its components (respiratory rate, heart rate, temperature, oxygen requirement, oxygen saturation and alertness level) prior to antibiotic initiation, with time-to-mortality in SAP. Methods We included patients with SAP (n=389) from a single hyperacute stroke unit. Diagnosis of SAP was made if pneumonia occurred within 7 days of hospital admission. Kaplan-Meier survival curves were generated to assess NEWS 2 parameters influencing survival at pre-defined time periods (1 year and 5 years). The association of these parameters on time-to-mortality were analysed using multivariable Cox regression models to account for a set of pre-specified potential confounders. Results The median age was 80y (71y-87y) and median NIHSS was 7 (IQR 4-17). Mortality within 1 year was 52.4% and 65.8% within 5 years. In the multivariable analyses, time-to-mortality was independently associated with respiratory rate (HR 1.04, 95% CI 1.01 to1.08, p=0.009) and total NEWS 2 score (HR 1.13, 95% CI 1.06 to 1.21, p=<0.001). Conclusions In patients with SAP, higher respiratory rate and total NEWS 2 score prior to antibiotic initiation were independently associated with time-to-mortality. Further studies are warranted to identify potential opportunities for intervention and ultimately guide treatment to improve outcomes in SAP patients.

The genome and comparative transcriptome of the euryhaline model ciliate Paramecium duboscqui reveal adaptations to environmental salinity

BackgroundAs a potential model organism for studies of environmental and cell biology, Paramecium duboscqui is a special euryhaline species of Paramecium that can be found in fresh, brackish, or marine water in natural salinity ranges between 0‰ and 33‰. However, the genome information as well as molecular mechanisms that account for its remarkable halotolerant traits remain extremely unknown. To characterize its genome feature, we combined PacBio and Illumina sequencing to assemble the first high-quality and near-complete macronuclear genome of P. duboscqui. Meanwhile, comparative transcriptomic profiles under different salinities gave underlying insight into the molecular mechanism of its adaptations to environmental salinity.ResultsThe results showed that the MAC genome of P. duboscqui comprises 160 contigs, with 113 of them possessing telomere (~ 28.82 Mb haploid genome size). Through comparative genomic analyses with the other ciliate, we found that gene families encoding transmembrane transporter proteins have been expanded in P. duboscqui, showing enormous potential in salinity adaptation. Like other Paramecium, P. duboscqui utilizes TGA as its only termination codon and has reassigned TAA and TAG to encode glutamine. P. duboscqui showed different growth rates under different salinities, with an optimum growth rate in 5‰ salinity. A comparison of the transcriptomic profiles among P. duboscqui grown under different concentrations showed that genes involved in protein folding, oxygen respiration, and glutathione-dependent detoxification were upregulated in the high-salt group, whereas genes encoding DNA-binding proteins and transcription factors were upregulated in the low-salt group, suggesting distinct mechanisms for responding to low and high salinity. Weighted gene coexpression network analysis (WGCNA) linked the hub genes expressed at 30‰ salinity to cysteine-type peptidase activity, lipid transfer, sodium hydrogen exchange, and cell division, with the hub genes expressed at 0‰ salinity involved in transmembrane transport and protein localization.ConclusionsThis study characterizes a new euryhaline model Paramecium, provides novel insights into Paramecium evolution, and describes the molecular mechanisms that have allow P. duboscqui to adapt to different osmotic environments.

Intimate microbe-water-mineral interactions mediate alkalization in the pyroxene-rich iron ore mines in Panxi area, Southwest China

In contrast to acid mine drainage, the microbial assembly and (bio)geochemical processes in alkaline mine conditions remain under-investigated. Here, microbe-water-mineral interactions were systematically investigated in two representative iron mines with alkaline conditions in the Panxi mining area, Southwest China. Compared to reference riverine samples less interfered by mining activities, the iron ore samples, composed of vanadium-titanium magnetite and pyroxene-rich bedrocks, exhibited elevated levels of Fe, HCl-extractable Fe(II), total sulfur, nitrate and sulfate, but lower total carbon (TC). Meanwhile, the mine drainage showed significantly higher sulfate, but lower TC concentrations than the riverine samples. Intriguingly, the Serpentinimonas spp., typically reported in serpentinites, prevailed in the microbial communities from the mine samples exhibiting higher pH. This suggests that the alkaline environments in Panxi mines result from serpentinization-like reactions. Enrichment of Thiobacillus spp. was observed in the mine-dwelling microbial communities, positively correlated with total sulfur, sulfate, nitrate, and Fe(II). Genome-resolved metagenomics suggested a chemoautotrophic lifestyle for the Thiobacillus species (e.g., carbon fixation, sulfur oxidation, and oxygen respiration), which may generate H+ and mitigate alkalization. This study provides valuable insights into progressive development of alkaline mine ecosystems and offers guidance for developing appropriate engineering strategies to restore the abandoned alkaline mines.

Pulmonary outcomes of incretin-based therapies in COPD patients receiving single-inhaler triple therapy

IntroductionPatients with chronic obstructive pulmonary disease (COPD) on triple therapy often face exacerbations and comorbidities. Emerging evidence suggests that glucagon-like peptide-1 (GLP-1) analogs may reduce the risk of exacerbation in patients with COPD and type 2 diabetes mellitus (T2DM). This study investigates the impact of GLP-1 analogs on pulmonary outcomes in patients with COPD on single-inhaler triple therapy (SITT) and T2DM.MethodsWe conducted a retrospective cohort study using the TriNetX database and analysed adult patients with COPD and T2DM who received SITT between April 2005 and July 2023. Patients were categorized into GLP-1 analog and dipeptidyl peptidase-4 inhibitors (DPP4i) cohorts. The primary efficacy outcome was COPD exacerbation and the secondary efficacy outcomes were pneumonia, acute respiratory distress syndrome, intubation, oxygen dependence, and all-cause mortality. The secondary outcomes were serious gastrointestinal adverse events.ResultsWe included 6898 patients, with 4184 receiving GLP-1 analogs and 2714 receiving DPP4i. After matching, 1751 GLP-1 analog users were matched with 1751 DPP4i users. GLP-1 analog users had an 18% lower risk of COPD exacerbation (hazard ratio [HR], 0.82 [95% CI: 0.71–0.94]), a 28% reduced risk of pneumonia (HR, 0.72 [95% CI: 0.61–0.85]), a 34% reduced risk of oxygen dependence (HR, 0.66 [95% CI: 0.47–0.91]), and a 40% decreased risk of all-cause mortality (HR, 0.60 [95% CI: 0.47–0.77]). No significant serious gastrointestinal adverse events were observed.ConclusionGLP-1 analogs may be associated with reduced COPD exacerbations, pulmonary comorbidities, and mortality in patients with COPD receiving SITT and T2DM, with no significant serious gastrointestinal safety concerns.

A multimodal characterization of cardiopulmonary resuscitation-associated lung edema

BackgroundCardiopulmonary resuscitation-associated lung edema (CRALE) is a phenomenon that has been recently reported in both experimental and out-of-hospital cardiac arrest patients.We aimed to explore the respiratory and cardiovascular pathophysiology of CRALE in an experimental model of cardiac arrest undergoing prolonged manual and mechanical chest compression (CC). Oxygen delivery achieved during mechanical or manual CC were also investigated as a secondary aim, to describe CRALE evolution under different hemodynamic supports generated during CPR.MethodsVentricular fibrillation (VF) was induced and left untreated for 5 min prior to begin cardiopulmonary resuscitation (CPR), including CC, ventilation with oxygen, epinephrine administration and defibrillation. Continuous mechanical and manual CC was performed alternating one of the two strategies every 5 min for a total of 25 min. Unsynchronized mechanical ventilation was resumed simultaneously to CC. A lung computed tomography (CT) was performed at baseline and 1 h after return of spontaneous circulation (ROSC) in surviving animals. Partitioned respiratory mechanics, gas exchange, hemodynamics, and oxygen delivery were evaluated during the experimental study at different timepoints. Lung histopathology was performed.ResultsAfter 25 min of CPR, a marked decrease of the respiratory system compliance with reduced oxygenation and CO2 elimination were observed in all animals. The worsening of the respiratory system compliance was driven by a significant decrease in lung compliance. The presence of CRALE was confirmed by an increased lung weight and a reduced lung aeration at the lung CT, together with a high lung wet-to-dry ratio and reduced airspace at histology. The average change in esophageal pressure during the 25-min CPR highly correlated with the severity of CRALE, i.e., lung weight increase.ConclusionsIn this porcine model of cardiac arrest followed by a 25-min interval of CPR with mechanical and manual CC, CRALE was consistently present and was characterized by lung inhomogeneity with alveolar tissue and hemorrhage replacing alveolar airspace. Despite mechanical CPR is associated with a more severe CRALE, the higher cardiac output generated by the mechanical compression ultimately accounted for a greater oxygen delivery. Whether specific ventilation strategies might prevent CRALE while preserving hemodynamics remains to be proved.

Prone position applied to COVID-19 patients: Systematic review-meta-analysis.

Position change and interventions to increase lung capacity should be considered in mechanically ventilated patients. The most effective of these is the prone position. This systematic review and meta-analysis aimed to determine the effects of the prone position on respiratory parameters and outcomes and to guide nurses working in the intensive care unit. This systematic review-meta-analysis was conducted in accordance with the Preferred Reporting in Systematic Reviews and Meta-Analyses guideline. ScienceDirect, CINAHL, Academic Search Complete (EBSCOhost), MEDLINE, EMBASE, Web of Science, Cochrane and PubMed databases were searched between January 2022 and January 2023 to access studies related to prone position in COVID-19 patients. Twenty-three studies were included. This meta-analysis shows that a prone position is feasible and can achieve improvements in gas exchange. Prone position increases PaO2/FiO2 in the majority of patients followed with a diagnosis of COVID-19 and severe hypoxemic. The study has shown that the prone position is effective in improving patients' respiratory function and oxygenation. The results presented in this article support the notion that the prone position can be an effective strategy in the clinical management of COVID-19 patients.

Predictors of nursing home conveyances to emergency department

BackgroundWith increasing rates of patient conveyances from nursing homes to emergency departments worldwide, we aim to examine factors causing high rates of conveyances from nursing homes to the emergency department (ED) of an acute tertiary hospital.MethodsThis was a prospective study involving presentation of ED attendances from nursing home residents during out-of-hours over a 23-month period from April 2020 to February 2022. Data was collected from a standardized manual form used by the Emergency Department to document nursing home conveyances.ResultsA total of 338 pre-conveyance forms were reviewed. The most common reasons for conveyances to ED were neurological symptoms (16%), unstable hemodynamics (12%), fever (11%) and falls (10%). The peak conveyances occurred between 1600 and 1900 h on weekends. Respiratory rate, oxygenation requirements and high National Early Warning Score (NEWS) were significantly associated with increased conveyances to the emergency department. When the components of NEWS were analyzed individually, decision for ambulance conveyance to emergency department was significantly associated with respiratory rate (p < .001), oxygen saturation (p < .001), and the use of oxygen supplementation (p < .005).ConclusionsUnstable hemodynamics and falls were among the leading factors for nursing home conveyances to the emergency department, which highlights the need to implement better fall prevention strategies and standardized parameters monitoring in nursing homes. Future research should focus on outcomes of conveyances and the characteristics of nursing home with higher conveyance rates. This would aid to assess the appropriateness of conveyances and to identify strategies to decrease preventable conveyances.

The effect of microbes and dissolved oxygen concentration on inorganic and organic substances elimination in a climate changing environment: The aerobic bioreactor

Microbes and dissolved oxygen (DO) concentration are the drivers in the wastewater treatment plant, aerobic bioreactor for the oxidation and decomposition of inorganic and organic substances. Due to global warming, surface and freshwater temperatures are increasing at an average of 1.08 °C. The rising climate temperatures suppress DO which threatens the availability of oxygen for respiration and survival of microbes, risking poor effluent being discharged into the environment. This study aimed to analyze the effect of microbes and DO concentration simultaneously on the elimination of inorganic and organic substances in a climate-changing environment. The results showed that biomass, COD (-0.578⁎⁎), and ammonia (-0.700⁎⁎) produced a negative relation while DO, ammonia (-0.214⁎⁎), and COD (-0.250⁎⁎) produced a negative relation. Although rising climate temperatures suppress DO, microbes strived under these conditions resulting in an effective aerobic bioreactor. Rising climate temperature (32.5 °C) produced the highest biomass (6.51 g/L), COD (145 mg/L), and ammonia (14.5 mg/L) elimination at the lowest DO (3.81 mg/L) concentration. Whereas normal operating temperature produced the lowest biomass (2.289 g/L), COD (94 mg/L), and ammonia (4.5 mg/L) elimination at the highest DO (4.83 mg/L) concentration. In addition, rising climate temperatures produced the highest COD (72.5 mg/L) and ammonia (7.25 mg/L) elimination rate compared with normal operating temperatures that produced the lowest COD (47 mg/L) and ammonia (2.25 mg/L) elimination rate. Therefore, the rising climate temperatures will not affect the microbes and DO concentration during the elimination of inorganic and organic substances, but rather enhance the performance of the aerobic bioreactor.

Respiratory muscle strength and oxygenation as predictors of length of hospital stay in patients with COVID-19

The aim was to analyze the prognostic value of ventilation/ gas exchange dissociation markers to predict the treatment length in patients with the acute phase of COVID-19.Materials and methods: The analysis was performed using a database of 384 randomly selected patients from December 2021 to May 2022 with a confirmed diagnosis of the acute phase of COVID-19, aged 61±16 years. Spirometry of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) was performed on 2,2±0,2 day of hospitalization with a portable MicroRPM device (CareFusion, UK) and measurement of surrogate oxygenation index (SpO2/FiO2), ROX index (SpO2/ FiO2)/respiratory rate) was carried out in all patients. Log-regression models were used (STATISTICA 10) to determine cutoff values for these functional variables and their ability to predict the patients length of hospital stay from the date of examination (≤ 7 vs &gt; 7 days).Results: The lowest sensitivity (SE) and specificity (SP) were shown in models using only the respiratory muscle strength markers MIP (SE=54%, SP=70%) and MEP (SE=73%, SP=47%), that were the same in the combination of MIP and MEP (SE=65%, SP=58%). The areas under ROC were equal to 0.6 in all three models. The models based on hypoxia markers had a higher classification power (AUC 0,7) compared to the previous three, and the sensitivity value was higher in the model using the ROX index (SE = 58% and SP = 78%), but the specificity was better in the surrogate oxygenation index model (SE = 48% and SP = 88%). A complex model based on a combination of the two integral hypoxia indices, as well as a diaphragm strength marker (SpO2/FiO2+MIP*ROX+MIP) had the best sensitivity (67%) and specificity (84%), and the area under ROC reached 0.8.Conclusion: Indicators of respiratory muscle strength and oxygenation are suitable markers for combined models and algorithms for predicting hospital length of stay in COVID-19 patients.

Benefits of chest wall mobilization on respiratory efficiency and functional exercise capacity in people with severe chronic obstructive pulmonary disease (COPD): A randomized controlled trial.

Coexistence of chest wall hypomobility and lung hyperinflation compromises respiratory muscle function and respiratory efficiency in people with severe chronic obstructive pulmonary disease (COPD). This study aimed to investigate the effect of chest wall mobilization on functional exercise capacity, respiratory muscle activity and respiratory muscle tissue oxygen saturation for people with severe COPD. Thirty male adults (age: 75 ± 6) diagnosed with severe COPD completed a 6-week programme (twice/week) according to intervention randomization (chest wall mobilization group, CWMG, n = 15; control group, CG, n = 15). Both groups received standardized education and walking exercise, while CWMG also received chest wall and thoracic spine mobilization. Electromyography of the essential and accessory respiratory muscles and tissue oxygen saturation of the intercostal muscle (StO2, measured by near-infrared spectroscopy) during incremental cycle exercise test were measured and compared between the two groups at pre-programme, post-programme and 3-month follow-up. Patients in CWMG demonstrated a significant increase in exercise tolerance from <3 METS to 4-6 METS (p = 0.000) after intervention. A significant decrease in activity of scalene, sternocleidomastoids and intercostal muscle during exercise test (p < 0.01) was found in CWMG, as compared to CG. A significant decrease in StO2 (p < 0.05) and greater decline in the slope of oxygenation dissociation (p = 0.000) were seen in CWMG during exercise test. These positive results were maintained at 3-month follow-up in CWMG. Improvements in exercise tolerance, respiratory muscle efficiency and oxygenation extraction ability in CWMG suggest a potential clinical benefit of integrating chest wall and thoracic spine mobilization for rehabilitation of people with severe COPD.

Spatial distribution of antioxidant activity in baguette and its modulation of proinflammatory cytokines in RAW264.7 macrophages

Baguette is a globally acclaimed bakery staple, composed by a crispy crust and soft crumb, both containing Maillard reaction products (MRPs) with potential bioactivities. However, MRPs’ impacts on the nutritional and health attributes of baguette, particularly in terms of cellular and biological functions, are yet to be clearly elucidated. This study chemically characterizes the crust and crumb of baguettes and investigates the influence of the Maillard reaction on baguette’s nutritional profile, especially in the antioxidant and anti-inflammatory effects. The findings indicate an increase in browning intensity and advanced glycation end products (AGEs) from the baguette’s interior to its exterior, alongside a significant rise in the antioxidant capacity of the crust, suggesting the Maillard reaction’s role in boosting antioxidative properties. Both the crust and crumb demonstrated strong cytocompatibility with immune cells, capable of reducing cellular oxidative stress and regulating intracellular free radical levels. The crust effectively countered peroxyl radical-induced cell membrane hyperpolarization by 91% and completely neutralized the suppression of oxygen respiration in mitochondria, displaying higher efficacy than the crumb. In contrast, crumb extracts were more potent in inhibiting lipopolysaccharide-induced expression of proinflammatory cytokines, such as interleukins-1β (IL-1β) and IL-6, in macrophages. It could provide the fundamental data and cell-based approach for investigating the biological impacts of bread on immune responses, contributing to the refinement and supplementation of nutritional recommendations.

Pushing the limits: expanding the temperature tolerance of a coral photosymbiont through differing selection regimes.

Coral thermal bleaching resilience can be improved by enhancing photosymbiont thermal tolerance via experimental evolution. While successful for some strains, selection under stable temperatures was ineffective at increasing the thermal threshold of an already thermo-tolerant photosymbiont (Durusdinium trenchii). Corals from environments with fluctuating temperatures tend to have comparatively high heat tolerance. Therefore, we investigated whether exposure to temperature oscillations can raise the upper thermal limit of D. trenchii. We exposed a D. trenchii strain to stable and fluctuating temperature profiles, which varied in oscillation frequency. After 2.1 yr (54-73 generations), we characterised the adaptive responses under the various experimental evolution treatments by constructing thermal performance curves of growth from 21 to 31°C for the heat-evolved and wild-type lineages. Additionally, the accumulation of extracellular reactive oxygen species, photophysiology, photosynthesis and respiration rates were assessed under increasing temperatures. Of the fluctuating temperature profiles investigated, selection under the most frequent oscillations (diurnal) induced the greatest widening of D. trenchii's thermal niche. Continuous selection under elevated temperatures induced the only increase in thermal optimum and a degree of generalism. Our findings demonstrate how differing levels of thermal homogeneity during selection drive unique adaptive responses to heat in a coral photosymbiont.

Effect on post-operative pulmonary complications frequency of high flow nasal oxygen versus standard oxygen therapy in patients undergoing esophagectomy for cancer: study protocol for a randomized controlled trial-OSSIGENA study.

Postoperative pulmonary complications (PPCs) remain a challenge after esophagectomy. Despite improvement in surgical and anesthesiological management, PPCs are reported in as many as 40% of patients. The main aim of this study is to investigate whether early application of high-flow nasal cannula (HFNC) after extubation will provide benefit in terms of reduced PPC frequency compared to standard oxygen therapy. Patients aged 18-85 years undergoing esophagectomy for cancer treatment with radical intent, excluding those with American Society of Anesthesiologists (ASA) score >3 and severe systemic comorbidity (cardiac, pulmonary, renal or hepatic disease) will be randomized at the end of surgery to receive HFNC or standard oxygen therapy (Venturi mask or nasal goggles) after early extubation (within 12 hours after the end of surgery) for 48 hours. The main postoperative goals are to obtain SpO2 ≥94% and adequate pain control. Oxygen therapy after 48 hours will be stopped unless the physician deems it necessary. In case of respiratory clinical worsening, patients will be supported with the most appropriate tool (noninvasive ventilation or invasive mechanical ventilation). Pulmonary [pneumonia, pleural effusion, pneumothorax, atelectasis, acute respiratory distress syndrome (ARDS), tracheo-bronchial injury, air leak, reintubation, and/or respiratory failure] complications will be recorded as main outcome. Secondary outcomes, including cardiovascular, surgical, renal and infective complications will also be recorded. The primary analysis will be carried out on 320 patients (160 per group) and performed on an intention-to-treat (ITT) basis, including all participants randomized into the treatment groups, regardless of protocol adherence. The primary outcome, the PPC rate, will be compared between the two treatment groups using a chi-square test for categorical data, or Fisher's exact test will be used if the assumptions for the chi-square test are not met. Recent evidence demonstrated that early application of HFNC improved the respiratory rate oxygenation index (ROX index) after esophagectomy but did not reduce PPCs. This randomized controlled multicenter trial aims to assess the potential effect of the application of HFNC versus standard oxygen over PPCs in patients undergoing esophagectomy. This study is registered at clinicaltrial.gov NCT05718284, dated 30 January 2023.

Study of Postacute Sequelae of COVID-19 Using Digital Wearables: Protocol for a Prospective Longitudinal Observational Study.

Postacute sequelae of COVID-19 (PASC) remain understudied in nonhospitalized patients. Digital wearables allow for a continuous collection of physiological parameters such as respiratory rate and oxygen saturation that have been predictive of disease trajectories in hospitalized patients. This protocol outlines the design and procedures of a prospective, longitudinal, observational study of PASC that aims to identify wearables-collected physiological parameters that are associated with PASC in patients with a positive diagnosis. This is a single-arm, prospective, observational study of a cohort of 550 patients, aged 18 to 65 years, male or female, who own a smartphone or a tablet that meets predetermined Bluetooth version and operating system requirements, speak English, and provide documentation of a positive COVID-19 test issued by a health care professional within 5 days before enrollment. The primary end point is long COVID-19, defined as ≥1 symptom at 3 weeks beyond the first symptom onset or positive diagnosis, whichever comes first. The secondary end point is chronic COVID-19, defined as ≥1 symptom at 12 weeks beyond the first symptom onset or positive diagnosis. Participants must be willing and able to consent to participate in the study and adhere to study procedures for 6 months. The first patient was enrolled in October 2021. The estimated year for publishing the study results is 2025. This is a fully decentralized study investigating PASC using wearable devices to collect physiological parameters and patient-reported outcomes. The study will shed light on the duration and symptom manifestation of PASC in nonhospitalized patient subgroups and is an exemplar of the use of wearables as population-level monitoring health tools for communicable diseases. ClinicalTrials.gov NCT04927442; https://clinicaltrials.gov/study/NCT04927442. DERR1-10.2196/57382.

Pressure Support Ventilation During Extracorporeal Membrane Oxygenation Support in Patients With Acute Respiratory Distress Syndrome.

In the initial phases of veno-venous extracorporeal membrane oxygenation (VV ECMO) support for severe acute respiratory distress syndrome (ARDS), ultraprotective controlled mechanical ventilation (CMV) is typically employed to limit the progression of lung injury. As patients recover, transitioning to assisted mechanical ventilation can be considered to reduce the need for prolonged sedation and paralysis. This study aimed to evaluate the feasibility of transitioning to pressure support ventilation (PSV) during VV ECMO and to explore variations in respiratory mechanics and oxygenation parameters following the transition to PSV. This retrospective monocentric study included 191 adult ARDS patients treated with VV ECMO between 2009 and 2022. Within this population, 131 (69%) patients were successfully switched to PSV during ECMO. Pressure support ventilation was associated with an increase in respiratory system compliance (p = 0.02) and a reduction in pulmonary shunt fraction (p < 0.001). Additionally, improvements in the cardiovascular Sequential Organ Failure Assessment score and a reduction in pulmonary arterial pressures (p < 0.05) were recorded. Ninety-four percent of patients who successfully transitioned to PSV were weaned from ECMO, and 118 (90%) were discharged alive from the intensive care unit (ICU). Of those who did not reach PSV, 74% died on ECMO, whereas the remaining patients were successfully weaned from extracorporeal support. In conclusion, PSV is feasible during VV ECMO and potentially correlates with improvements in respiratory function and hemodynamics.

A cytochrome bd repressed by a MarR family regulator confers resistance to metals, nitric oxide, sulfide, and cyanide in Chromobacterium violaceum.

The terminal oxidases of bacterial respiratory chains rely on heme-copper (heme-copper oxidases) or heme (cytochrome bd ) to catalyze reduction of molecular oxygen to water. Chromobacterium violaceum is a facultative anaerobic bacterium that uses oxygen and other electron acceptors for respiration under conditions of varying oxygen availability. The C. violaceum genome encodes multiple respiratory terminal oxidases, but their role and regulation remain unexplored. Here, we demonstrate that CioAB, the single cytochrome bd from C. violaceum , protects this bacterium against multiple stressors that are inhibitors of heme-copper oxidases, including nitric oxide, sulfide, and cyanide. CioAB also confers C. violaceum resistance to iron, zinc, and hydrogen peroxide. This cytochrome bd is encoded by the cioRAB operon, which is under direct repression by the MarR-type regulator CioR. In addition, the cioRAB operon responds to quorum sensing and to cyanide, suggesting a protective mechanism of increasing CioAB in the setting of high endogenous cyanide production.

Physiological effects and safety of bed verticalization in patients with acute respiratory distress syndrome

BackgroundTrunk inclination in patients with Acute Respiratory Distress Syndrome (ARDS) in the supine position has gained scientific interest due to its effects on respiratory physiology, including mechanics, oxygenation, ventilation distribution, and efficiency. Changing from flat supine to semi-recumbent increases driving pressure due to decreased respiratory system compliance. Positional adjustments also deteriorate ventilatory efficiency for CO2 removal, particularly in COVID-19-associated ARDS (C-ARDS), indicating likely lung parenchyma overdistension. Tilting the trunk reduces chest wall compliance and, to a lesser extent, lung compliance and transpulmonary driving pressure, with significant hemodynamic and gas exchange implications.MethodsA prospective, pilot physiological study was conducted on early ARDS patients in two ICUs at CHU Clermont-Ferrand, France. The protocol involved 30-min step gradual verticalization from a 30° semi-seated position (baseline) to different levels of inclination (0°, 30°, 60°, and 90°), before returning to the baseline position. Measurements included tidal volume, positive end-expiratory pressure (PEEP), esophageal pressures, and pulmonary artery catheter data. The primary endpoint was the variation in transpulmonary driving pressure through the verticalization procedure.ResultsFrom May 2020 through January 2021, 30 patients were included. Transpulmonary driving pressure increased slightly from baseline (median and interquartile range [IQR], 9 [5–11] cmH2O) to the 90° position (10 [7–14] cmH2O; P < 10–2 for the overall effect of position in mixed model). End-expiratory lung volume increased with verticalization, in parallel to decreases in alveolar strain and increased arterial oxygenation. Verticalization was associated with decreased cardiac output and stroke volume, and increased norepinephrine doses and serum lactate levels, prompting interruption of the procedure in two patients. There were no other adverse events such as falls or equipment accidental removals.ConclusionsVerticalization to 90° is feasible in ARDS patients, improving EELV and oxygenation up to 30°, likely due to alveolar recruitment and blood flow redistribution. However, there is a risk of overdistension and hemodynamic instability beyond 30°, necessitating individualized bed angles based on clinical situations.Trial registration ClinicalTrials.gov registration number NCT04371016, April 24, 2020.