Clinical Research Directory

Spontaneous vs Controlled Mechanical Ventilation in Acute Hypoxemic Respiratory Failure

Acute hypoxemic respiratory failure may progress to acute respiratory distress syndrome, a life-threatening condition that often requires mechanical ventilation. The optimal ventilation strategy in this patient population remains uncertain. The SVALBARD trial is a feasibility and pilot study designed to compare spontaneous versus controlled mechanical ventilation in patients with acute hypoxemia respiratory failure. The primary objective is to assess the feasibility of the study procedures and interventions, while also collecting descriptive data on key clinical variables to inform the design of a future randomized controlled trial.

Adherence to Low Tidal Volume in the Transition to Spontaneous Ventilation in Patients With Acute Respiratory Failure

The goal of this observational study is to estimate the prevalence of the use of protective ventilation with low tidal volume ventilation in the transition of spontaneous ventilation modes in patients with hypoxemic acute respiratory failure in ICUs in Latin America and its association with patient outcomes. The main questions it aims to answer are: * what is the prevalence of the use of low tidal volume ventilation (VT \<8 mL/kg of predicted body weight) in the first 24 hours of spontaneous ventilation modes in patients with hypoxemic acute respiratory failure? * Is there an association between the rate of adherence to low tidal volume ventilation in spontaneous ventilation modes and the ability to stay off ventilatory support and mortality? Participants are patients with acute respiratory failure under mechanical ventilation. Investigators will collect data on the ventilatory parameters of participants * 24 hours before they begin to be ventilated with spontaneous modes of ventilation * during the first 24 hours of spontaneous ventilation Investigators will collect several patient-centered clinical outcomes at 28 days after study inclusion, including ventilator-free days and mortality

Interleukin-6 Guided Treatment With Dexamethasone or Tocilizumab in Patients Hospitalized With Acute Respiratory Symptoms - a Feasibility Study

Acute hypoxemic respiratory failure (AHRF) happens when the lungs are unable to absorb enough oxygen. The bloodstream is deprived of oxygen which can eventually lead to more severe conditions like multi-organ failure (MOF) and death. AHRF accounts for over 30% of patients to critical care units, thus novel treatments are sorely needed. Research has shown that blood levels of the inflammatory biomarker Interleukin-6 (IL-6) may be a reliable marker for predicting which patients with AHRF will progress into requiring intensive care unit (ICU) admission, MOF, and eventually death. IL-6 levels were shown to reliably peak several days before MOF, ICU admission, and death. Thus, the investigators believe that by identifying patients before the peak of their IL-6 levels, they will be able to administer early treatment to prevent the patient's condition from worsening. The aim of this study is to test the feasibility of a treatment strategy for AHRF based on IL-6 measurement in patients who are admitted to hospital care with AHRF. This study has two phases: 1) observational and 2) interventional. In the observational phase 1, patients who meet the inclusion and a general exclusion criteria are eligible for participation. In the observational phase, patients will have their plasma IL-6 levels measured over 2 days. Patients' clinical condition will be observed till discharge or up to 28 days of admission, and data will be collected from their medical charts. Patients participating in the observational phase 1 will be considered eligible to join the interventional phase 2 if: they are found to have elevated IL-6 levels, and they meet additional randomization exclusion criteria. In the interventional phase, patients will be randomized into 1 of 3 treatment groups: standard of care only, standard of care plus a single IV infusion of Tocilizumab, or standard of care plus treatment with oral Dexamethasone for 10 days. Patients' clinical condition will be observed till discharge or up to 28 days of admission, and data will be collected from their medical charts. A follow-up phone interview will be conducted 6 months of the end of the observation period. Patients participating in the observational phase 1 who are not eligible to participate in the interventional phase 2 will continue in the observational phase 1 only. These patients will not be randomized to a group, receive any study medications, or be contacted for the 6-month follow-up.

Physiological Effects of Continuous Negative External Pressure for Acute Hypoxemic Respiratory Failure

This study is being conducted to evaluate if wearing a non-invasive breathing support device over the chest/abdomen improves markers of breathing in patients with lung injury requiring high-flow oxygen. The breathing support device consists of a plastic shell that sits over the chest and abdomen and connects to a vacuum that helps the chest expand with breathing. This breathing support is known as continuous negative external pressure (CNEP). Study findings will help determine if this breathing support device might be useful for patients with acute hypoxemic respiratory failure (AHRF).

Optimizing Care in Critically Ill at UCHealth by Liberalizing the Target O2 in Mechanically-ventilated ICU Patients

A multimodal educational intervention to target an oxygen saturation target range (SpO2 90-96%) will reduce ventilator length of stay and reduce occult hypoxemia by increased awareness and adherence to a designated oxygen saturation target range.

Protocolized Weaning of High-Flow Nasal Cannula in Adult Patients

High-flow nasal cannula (HFNC) is a type of oxygen therapy commonly used in adults with breathing problems. While HFNC can help patients avoid breathing tubes and improve oxygen levels, there is no standard method for deciding how and when to reduce and stop this therapy once a patient improves. In many hospitals, these decisions vary from clinician to clinician. This study will compare usual care with a standardized step-by-step plan for reducing HFNC support. Eight hospitals will participate and will switch from usual care to the standardized plan at different time points during the study. The main goal is to determine whether the standardized weaning plan increases the number of patients who can successfully stop HFNC within 5 days. The study will also evaluate how long patients remain on HFNC, whether they need additional breathing support, and how long they stay in the hospital. The results may help develop clearer guidance for safely and efficiently stopping HFNC therapy.

Efficacy of DEXamethasone in Patients With Acute Hypoxemic REspiratory Failure Caused by INfEctions

Background: There are no proven therapies specific for pulmonary dysfunction in patients with acute hypoxemic respiratory failure (AHRF) caused by infections (including Covid-19). The full spectrum of AHRF ranges from mild respiratory tract illness to severe pneumonia, acute respiratory distress syndrome (ARDS), multiorgan failure, and death. The efficacy of corticosteroids in AHRF and ARDS caused by infections remains controversial. Methods: This is a multicenter, randomized, controlled, open-label clinical trial testing dexamethasone in mechanically ventilated adult patients with established AHRF (including ARDS) caused by confirmed pulmonary or systemic infections, admitted in a network of Spanish ICUs. Eligible patients will be randomly assigned to receive dexamethasone: either 6 mg/d x 10 days or 20 mg/d x 5 days followed by 10 mg/d x 5 days. The primary outcome is 60-day mortality. The secondary outcome is the number of ventilator-free days at 28 days. All analyses will be done according to the intention-to-treat principle.

Early Switch From Controlled to Assisted Ventilation

The goal of this physiological intervention study is to unravel the (patho)physiological mechanisms and potential clinical benefits of a pre-specified early switch from controlled to assisted ventilation in mechanically ventilated adult patients with acute hypoxemic respiratory failure (PaO2/FiO2 ratio \< 200 mmHg). The intervention is that participants will be switched from controlled to assisted ventilation when PaO2/FiO2 ratio \> 200 mmHg. The primary endpoint is the change in regional lung stress (as derived by electrical impedance tomography) when switching from controlled to assisted ventilation and until a successful or failed switch.

EndotyPIng PreHospitAl de Novo Acute hYpoxemic Respiratory Failure

We attempt to perform dynamic endotyping of critically ill patients presenting in the emergency department with de novo acute hypoxemic respiratory failure (AHRF). We also attempt to identify what clinical, radiological, physiological and biological variables collected early in the course of AHRF correlate with subsequent mortality and/or persistent severe hypoxemia.

EARLY-SARDS: Early AlveolaR Lung biologY Underling Sepsis-Associated ARDS

Sepsis-associated acute respiratory distress syndrome (ARDS) remains a major cause of respiratory failure and mortality in critically ill patients. Although only a proportion of patients with sepsis develop ARDS, early identification of those at highest risk remains a major unmet clinical need. Current prediction relies largely on clinical deterioration and oxygenation impairment, which often occur when lung injury has already developed. Increasing evidence suggests that biological responses to sepsis are compartmentalized between the systemic circulation and the alveolar space, while early abnormalities in respiratory mechanics and ventilatory efficiency may provide complementary information on evolving lung injury. However, no prospective study has integrated serial systemic and alveolar biomarkers with bedside respiratory physiology during the earliest phase of sepsis-associated respiratory failure. EARLY-SARDS is a prospective observational cohort study designed to characterize the early biological and physiological trajectories of invasively ventilated patients with sepsis or septic shock. Serial bronchoalveolar lavage (BAL) and plasma samples, together with standardized measurements of respiratory mechanics and gas exchange, will be collected during the first 96 hours after enrollment. The primary objective is to develop an integrated biological-physiological model capable of predicting ARDS development and subsequent peak ARDS severity. Secondary objectives include characterizing biological compartmentalization, identifying integrated biological-physiological subphenotypes, and evaluating their association with clinically relevant outcomes, including duration of mechanical ventilation, ventilator-free days, need for extracorporeal respiratory support, ICU length of stay, and mortality.

IntHyx : Intubation Strategies for Patients With Acute Hypoxemic Respiratory Failure

Acute hypoxemic respiratory failure requires endotracheal intubation and invasive mechanical ventilation in approximately 30-40% of cases, due to severe hypoxemia and/or clinical signs of acute respiratory distress. The primary objectives of invasive mechanical ventilation are to reduce respiratory effort and improve oxygenation. However, this intervention is also associated with both direct and indirect adverse effects, mainly linked to the need for sedation and often neuromuscular blockade. These include hemodynamic compromise, neuromuscular weakness, ventilator-induced lung injury, and infectious complications. An ideal intubation strategy would therefore strike a balance: avoiding the risks of delayed intubation-such as refractory hypoxemia, excessive respiratory effort, and patient self-inflicted lung injury (P-SILI)-while limiting complications associated with invasive mechanical ventilation by withholding it in patients who might otherwise recover without. To date, the optimal strategy for achieving this risk-benefit balance remains uncertain. Clinical practice suggests a broad consensus on the necessity of intubation when so-called safety criteria are met: severe hypoxemia (SaO₂/FiO₂ ratio \< 88), marked respiratory distress (use of accessory muscles, thoracoabdominal paradox, respiratory rate \> 40/min), extra-respiratory manifestations of hypoxia (e.g., altered consciousness), and/or uncontrolled hemodynamic instability. Beyond these safety thresholds, however, debate persists. Some advocate for earlier intubation-a so-called liberal approach-triggered by predefined hypoxemia criteria (e.g., SpO₂/FiO₂ \< 110), with the aim of limiting the deleterious consequences of sustained hypoxemia. In routine practice, the criteria guiding intubation vary widely between clinicians and cannot be attributed to strong scientific evidence. This study therefore seeks to compare, in a randomized interventional design, the two main strategies currently applied across centers: * Liberal intubation strategy: prioritizing the prevention of organ dysfunction related to hypoxemia (notably hypoxic cardiac arrest) and the risk of P-SILI. * Restrictive intubation strategy: prioritizing the reduction of invasive mechanical ventilation use, with the goal of minimizing ventilation-related harm and its associated therapeutic burden.

Is Hypoxemia Driving Outcome in Acute Hypoxemic Respiratory Failure? (HOMELAND Study)

Acute hypoxemic respiratory failure (AHRF) is the most common cause of admission in the intensive care units (UCIs) worldwide. The investigators will assess the value of mediation analysis (a statistical method to understand the mechanism or process through which an independent variable influences a dependent variable (prediction of early ICU death) via a mediator variable. This allows researcher to see the "how" and "why" of a causal link, respecting the timing relationships" o "maintaining appropriate time constants in patients with AHRF me, We had a database with 2,000,000 anonymized and dissociated demographics and clinical data from 1,241 patients with AHRF enrolled in our PANDORA cohort (Prevalence AND Outcome of acute Respiratory fAilure) registered with ClinicalTrails.gov (NCT013145974) from 22 Spanish hospitals and funded by the ISCIII. The study was approved by the Ethics Committees for Clinical research of participating hospitals and informed consent was waived based on Spanish legislation for biomedical research (Royal Decrees 1090/2015 and 957/2020). The investigators will use mediation analysis (Baron \& Kenny techniques) to clarify the association of extrapulmonary organ dysfunction and hypoxemia in the early prediction of ICU mortality. We will analyze 1,241 patients mechanically ventilated with AHRF at the time of diagnosis, 1,193 with data at 24 hours, and 996 patients with data at 48 hours from a epidemiological study in Spain.

Machine Learning Model to Predict Outcome in Acute Hypoxemic Respiratory Failure

Acute hypoxemic respiratory failure (AHRF) is the most common cause of admission in the intensive care units (UCIs) worldwide. We will assess the value of machine learning (ML) techniques for early prediction of ICU death in 1,241 patients enrolled in the PANDORA (Prevalence AND Outcome of acute Respiratory fAilure) Study in Spain. The study was registered with ClinicalTrials.gov (NCT03145974). Our aim is to evaluate the minimum number of variables models using logistic regression and four supervised ML algorithms: Random Forest, Extreme Gradient Boosting, Support Vector Machine and Multilayer Perceptron.

Prediction of Duration of Mechanical Ventilation in Acute Hypoxemic Respiratoty Failure

Acute hypoxemic respiratory failure (AHRF) is a common cause of admission in intensive care units (ICUs) worldwide. We will assess machine learning (ML) techniques for prediction of prolonged duration (\> or = to 7 days) of mechanical ventilation (MV) in 1,241 patients enrolled in the PANDORA study in Spain. The study was registered with ClinalTrials.gov (NCT03145974). Our aim is to identify a model with the minimum number of variables that predict duration of prolonged ventilation in AHRF patients using data as early as from the first 48 hours with machine learning algorithms.

Predicting High-Flow Nasal Cannula Failure in Acute Hypoxemic Respiratory Failure Using Metabolomics and Clinical Data

The goal of this observational study is to determine whether metabolomic profiles combined with clinical data can predict high-flow nasal cannula (HFNC) failure and help optimize respiratory support in adult patients with acute hypoxemic respiratory failure (AHRF). The main questions it aims to answer are: Can metabolomic biomarkers identify patients at higher risk of HFNC failure? Does combining metabolomic and clinical data improve the prediction of respiratory support escalation and clinical outcomes? Participants will: Receive standard HFNC treatment according to clinical practice. Undergo collection of clinical, physiological, and laboratory data. Provide blood samples for metabolomic analysis during respiratory support.

Targeting prEssure-Muscle-index to Avoid Ventilatory Over-Assistance During Pressure Support Ventilation

The TEMA study (Targeting prEssure-Muscle-index to avoid ventilatory over-Assistance during pressure support ventilation) is a prospective, interventional crossover trial investigating the relationship between pressure support (PS) and tidal volume (Vt) in ICU patients with acute hypoxemic respiratory failure (AHRF) receiving pressure support ventilation (PSV). The study aims to assess whether the Pressure-Muscle Index (PMI)-a marker derived from the difference between plateau and peak inspiratory pressure-can help identify the optimal level of ventilatory assistance, preventing over-assistance and its associated complications such as diaphragm atrophy and patient self-inflicted lung injury (P-SILI). By exploring the sigmoidal relationship between PS and Vt, the study seeks to define a physiological threshold (PMI=0) that may serve as a personalized target for PSV titration.

Association Between EIT and CT During PEEP Titration in Patients With Acute Respiratory Failure

This observational study will analyze data already collected by the investigators as part of their routine clinical practice from patients with acute respiratory failure (ARF) treated with mechanical ventilation. The study itself does not require any specific intervention. Mechanical ventilation can save the lives of patients with ARF. However, if used improperly, it can exacerbate lung disease and worsen outcomes (Slutsky et al.). Despite decades of animal and clinical research, it remains unclear how to establish the positive end-expiratory pressure (PEEP) during mechanical ventilation to reduce the risk of lung damage. Several methods have been suggested, but none have consistently proven superior to the others (Sahetya et al.). As part of their routine clinical practice, the investigators study the responses to different PEEP levels of patients with ARF undergoing mechanical ventilation by integrating information from various techniques, each examining different aspects of lung morphology and physiology. The methods the investigators use include lung computed tomography (CT) and electrical impedance tomography (EIT). Lung CT is the reference technique for measuring the morphological response to PEEP (Gattinoni et al.). It quantifies the volume of the hyperinflated and non-aerated lung, both of which are related to the risk of mechanical ventilation causing damage (Slutsky et al.). Lung EIT monitors the functional response to PEEP in terms of changes in regional compliance across different PEEP levels. Allegedly, an increase in compliance when PEEP is decreased reveals overdistention, the functional correlate of (worrisome) hyperinflation, at the higher PEEP. A decrease in compliance when PEEP is decreased signals new collapse, the functional correlate of (worrisome) loss of aeration (Franchineau et al.). In the Unit where the investigators work, patients with ARF treated with mechanical ventilation are routinely studied as follows. First, a lung CT with a PEEP of 20 cmH2O and then of 5 cmH2O is obtained. Thereafter, a decremental PEEP test is performed with the EIT, where PEEP is decreased from 20 cmH2O down to 5 cmH2O in steps of 2 or 3 cmH2O. Finally, results are analyzed and compared offline. At the lung CT, decreasing PEEP from 20 to 5 cmH2O is always associated with some decrease in the volume of the hyperinflated lung and some increase in the volume of the non-aerated lung. However, the magnitude of these two effects varies among individuals, and the net response may be defined as the difference between those two competing effects. If the decrease in the volume of the hyperinflated lung is greater than the increase in the volume of the non-aerated lung, the overall response (i.e., less hyperinflation) can be considered positive. PEEP should then be set closer to 5 than to 20 cmH2O. Diversely, if the decrease in the volume of the hyperinflated lung is smaller than the increase in the volume of the non-aerated lung, the overall response (i.e., more loss of aeration) can be considered negative. PEEP should then be set closer to 20 cmH2O (Protti et al.). Similarly, at the lung EIT, decreasing PEEP from 20 to 5 cmH2O is always associated with compliance improvement in some regions (i.e., less overdistension) and worsening in others (i.e., more collapse). Again, the magnitude of these two opposite effects varies among individuals. According to most experts on lung EIT, PEEP should be set at the level where both overdistension and collapse are minimized (the so-called "best" PEEP) (Jonkman et al.). Lung CT requires transfer to the radiology unit, exposure of the patient to radiation, and complex analysis offline. By contrast, lung EIT is virtually risk-free, and analysis can be performed using an automatic algorithm. Nevertheless, lung EIT is less well validated than lung CT. For instance, the assumption that a decrease in compliance in response to a decrease in PEEP is due to new collapse has been questioned (Protti et al., Chiumello et al., Menga et al.). So far, lung CT remains the reference technique for studying individual responses to PEEP, while lung EIT requires further validation. This study aims to verify whether the "best" PEEP identified using lung EIT is strongly associated with the net response assessed using lung CT, when PEEP is decreased from 20 to 5 cmH2O in patients with ARF treated with mechanical ventilation. If so, this would strengthen the rationale for using the lung EIT (which is safer and simpler than the lung CT) to set PEEP.

Awake Prone Positioning in Spontaneous Breathing Patients With Acute Hypoxic Respiratory Failure Due to Pneumonia

Prone positioning has shown beneficial effects in intubated patients with severe respiratory failure and positive effects in awake patients with COVID-19 pneumonia. Conclusive evidence for patients with AHRF without COVID-19 is still missing. The investigators hypothesis that awake prone position in patients with AHRF is superior to standard supine/semi-recumbent position in terms of reducing the rate of tracheal intubation and/or all-cause death within 28 days after randomization.

Bag CPAP vs Standard Oxygen Therapy in Acute Hypoxemic Respiratory Failure

Acute Hypoxemic Respiratory Failure (AHRF) is one of the prevalent causes of admission around the world and is associated with high mortality in resource-limited settings. Limited access to invasive mechanical ventilation is among the contributing factors to poor outcomes. The Bag CPAP may be useful in reducing the need for intubation and therefore mortality in patients with AHRF but data are lacking. This study aims to determine whether the Bag CPAP compared to standard oxygen care, could reduce the percentage of patients with criteria for intubation in patients with AHRF. This is a prospective randomized, open-label, controlled trial in which patients presenting at the emergency room in Rwanda will be randomly assigned to receive standard oxygen therapy or Bag CPAP. The primary endpoint is the percentage of patients with criteria for intubation at day 7. Secondary endpoints include the tolerance of the Bag CPAP, overall 28-day mortality rate, mortality rate of intubated patients on mechanical ventilation at day 28, percentage of patients intubated at 28 days, ventilator-free days at day 28, interval between the initiation of treatment and the onset of intubation criteria, the interval between the time when criteria for intubation are met and intubation, organ failure-free days at day 7 and length of hospital stay.

HNFO With or Without Helmet NIV for Oxygenation Support in Acute Respiratory Failure Pilot RCT

This Randomized Control Trial will directly compare helmet non-invasive ventilation (NIV) combined with high flow nasal oxygen (HFNO) versus HFNO alone in patients with Acute Hypoxemic Respiratory Failure (AHRF).

Evaluation of Physical Capacity and Energy Requirements in Patients With Hypoxemic Acute Respiratory Failure

NIVAR01 (Multimodal evaluation of physical capacity and energy requirements in patients with hypoxemic acute respiratory failure and community acquired pneumonia under non invasive ventilation support) aims to comprehensively assess energy requirements and physical capacity in patients with acute hypoxemic respiratory failure (AHRF) due to community-acquired pneumonia (CAP) undergoing non-invasive ventilation (NIV). Through a stepwise, multimodal approach integrating physiological measurements, imaging, and molecular biomarkers, the project seeks to identify patient subphenotypes that can guide targeted interventions, improve outcomes, and reduce the need for invasive mechanical ventilation. The project is structured in five progressive phases, each building on the findings of the previous one to refine and personalize care strategies. The first phase of the project aims to assess the correlation between BIA (bioelectrical impedance analysis) and IC (indirect calorimetry) in sedated patients, in oder to extrapolate this correlation in patients under NIV in the next phase. The second phase uses this correlation to validate the use of indirect calorimetry (IC) in patients under non-invasive ventilation (NIV) by comparing it with data obtained from patients under invasive mechanical ventilation, where IC is better established and technically more accurate. This comparative approach will serve to assess the reliability and feasibility of IC in NIV settings, incorporating correction factors for air leaks and comparing with BIA data, laying the groundwork for its integration with other physiological and biochemical measurements in subsequent phases. The third phase expands to a multimodal prospective observational cohort study integrating IC, BIA, ultrasound, biomarkers of mitochondrial and endothelial dysfunction, and innate immune system paralysis. These data will be used for patient phenotyping through advanced machine learning. The fourth and fifth phases will develop and test personalized nutritional and motor interventions (e.g., phrenic nerve stimulation, tailored physiotherapy) in clinical trials based on identified patient subtypes. Previous studies (Georges et al., Siirala et al., Singer 2024) have demonstrated the feasibility of using IC in NIV patients, although limited by methodological constraints. This project brings novelty by incorporating BIA-derived metabolic rate estimates and segmental analysis, offering new insights into body composition, fluid balance, and muscle integrity, including diaphragm function. Additionally, biomarkers such as cf-mtDNA, FGF-21, GDF-15, HSP60/10, and cytokine profiles (TNFα, IL-6, IL-10, CRP), as well as endothelial markers (e-Selectin, sICAM-1, vCAM-1, Syndecan-1), will be analyzed. Immune paralysis will be studied via monocyte HLA-DR expression and LPS-stimulated cytokine release. By leveraging multimodal data integration and gender-specific analysis, NIVAR 01 aims to optimize prediction of NIV failure beyond current tools such as the HACOR index and enable individualized patient management.

PEEP-induced Effects on Respiratory dRivE and EFfort

Rationale: In patients with acute hypoxemic respiratory failure (AHRF), preserving spontaneous breathing during mechanical ventilation offers physiological benefits, but also carries risks. While spontaneous breathing improves gas exchange and limits diaphragm atrophy, strong inspiratory efforts may worsen lung and diaphragm injury. Balancing these factors requires refined and tailored strategies, such as the modulation of PEEP. However, the impact of PEEP on neural respiratory drive and inspiratory effort is very heterogenous, and these two entities have only been studied separately in limited subsets of patients and healthy subjects. Additionally, it remains unclear whether the major determinant of PEEP-induced changes in respiratory drive and effort is represented by variations in diaphragm geometry, lung compliance, or by the presence of expiratory muscles recruitment, which may counteract its effect. Objective: The primary objective is to determine the effect of PEEP on diaphragm neuromechanical efficiency (i.e. an index of neural respiratory drive and inspiratory effort) in patients with acute hypoxemic respiratory failure during invasive assisted mechanical ventilation. The secondary objective is to determine the major physiological contributors to PEEP-mediated changes in diaphragm neuromechanical efficiency. Study design: Prospective, physiological study. Study population: Invasively mechanically ventilated adult patients admitted to the ICU. Intervention: For each patient, six different PEEP levels (15-12-10-8-5-2 cmH2O) will be tested during a decremental PEEP trial. During each step, neural respiratory drive, inspiratory effort, expiratory muscle activity, lung inflation pattern through electrical impedance tomography, respiratory muscle geometry and function through ultrasound and surface EMG, gas exchange and hemodynamics data will be collected. Main study parameters/endpoints: The primary outcome of the study will be the evaluation of PEEP-mediated changes in diaphragm neuromechanical efficiency (NME).

Assessment of PaO2/FiO2 Ratio Pre and POst INTubation

We designed this study to dtermine whether invasive mechanical ventilation (MV) would have an impact on the reclassification of patients with acute hypoxemic respiratory failure (AHRF) -treated previously with non-invasive respiratory support- into categories of severity (mild, moderate, and severe). Our hypothesis is that the assessment of PaO2/FiO2 ratio on PEEP greater or equal to 5 cmH2O after intubation, in patients labeled as mild/moderate/severe AHRF while on non-invasive respiratory support, would identify that a marked proportion of patients would change the degree of severity after a brief period of invasive MV

Weaning Protocol for High-flow Nasal Oxygen Therapy in Intensive Care

High-flow nasal oxygen therapy (HFNO) is an oxygenation technique frequently used in intensive care. The main objective of our study is to show that the use of a protocol for weaning patients off high-flow nasal oxygen therapy (HFNO) in the intensive care unit increases the probability that patients will be weaned from HFNO at Day 7 post-randomisation. This is a open-label multicentre randomised controlled trial conducted in two parallel groups. The primary endpoint is the success rate at Day 7, with success defined as "definitive" weaning from HFNO, i.e. patients weaned from HFNO for more than 48 hours without recourse to non-invasive ventilation (NIV) or intubation and still alive at Day 7. The weaning protocol will be started as soon as the patient meets all the inclusion criteria, considered to be the prerequisites for initiating weaning from HFNO. Patients will be monitored until Day 28 maximum.