Clinical Research Directory

Influence of Personalized Lung Volume Optimization Maneuver on Lung Function and Cardiac Performance in Children

The goal of this randomized interventional clinical trial is to learn if a standardized lung volume optimization maneuver (LVOM) is beneficial in 1. study) children undergoing biventricular repair of their congenital heart disease (CHD) with cardiopulmonary bypass and 2. study) in children with severe respiratory failure at risk for or need for ECMO. The main questions it aims to answer are: Main hypotheses of CHD study: Does a standardized PEEP-Titration maneuver, to optimize end-expiratory lung volume improve: * cardiac performance * lung function Does it make a difference in: * length of ventilation * ventilation/perfusion mismatch of the lung * need for vasopressor support? Main hypotheses of ECMO study: Does a LVOM in children/infants with severe respiratory failure /ARDS * improve lung compliance and gas exchange * facilitate lung protective ventilation according to PALICC-2 guidelines * improve lung aeration and V/Q-matching assessed with EIT Does it make a difference in * need for ECMO * duration of ECMO runs * hemodynamics stability

Effects of Periodic Recruitment Maneuvers on Atelectasis and Respiratory Mechanics During Elective Spine Surgery Assessed by Lung Ultrasonography

During general anesthesia, particularly in patients undergoing spine surgery in the prone (face-down) position, increased intrathoracic and abdominal pressure may reduce lung compliance and promote the development of atelectasis (partial lung collapse). Atelectasis can impair intraoperative oxygenation and may increase the risk of postoperative pulmonary complications. Alveolar recruitment maneuvers (ARM) are routinely used in anesthesia practice to reopen collapsed lung regions; however, it remains unclear whether periodic application of ARM throughout surgery provides additional benefit compared with standard single-time application. This prospective, randomized controlled clinical study aims to evaluate whether periodic alveolar recruitment maneuvers applied during elective spine surgery in the prone position reduce intraoperative atelectasis and improve respiratory mechanics compared with the standard approach of performing ARM only after positioning and before extubation. Adult patients undergoing elective spine surgery under general anesthesia will be randomly assigned to either a periodic ARM group or a standard ARM group. Lung aeration will be assessed using lung ultrasound, a non-invasive and radiation-free bedside imaging method. The primary outcome is the incidence of intraoperative atelectasis assessed before extubation. Secondary outcomes include lung ultrasound aeration scores, respiratory mechanics parameters (such as airway pressures and compliance), oxygenation indices, and the occurrence of transient intraoperative respiratory or hemodynamic events. The findings of this study may help optimize intraoperative ventilation strategies in prone spine surgery and contribute to improved perioperative respiratory safety.

Fentanyl Versus Hydromorphone in Patients on Mechanical Ventilation

Patients with respiratory failure who require mechanical ventilation are not only at risk of death, but also of complications of prolonged ICU stay. Patients may have significant functional decline, impact in quality of life, develop psychiatric disorders and at long-term can lead to significant cost to society. Although sedation and analgesia are considered only supportive therapy, several studies have shown that in patients on mechanical ventilation, different approaches can have significant impact on patient centered outcomes. However, to date, randomized clinical trials on critically ill patients have mostly evaluated the sedative agent but not the analgesic agent. Although morphine and its derivates are the most common used opioid analgesic agents in the critical care setting, only some retrospective studies and some prospective studies compared them head-to-head (ramifentanyl versus morphine and fentanyl versus morphine). Current guidelines recommend choosing the analgesic agent based on pharmacokinectics, physician experience and side-effects profile. To evaluate the differences of two standard-of-care analgosedation agents, the FenHydro trial will be a cluster randomized, pragmatic, pilot and feasibility superiority clinical trial in mechanically ventilated patients in the ICU. The main question the study hopes to answer is whether there is any difference in morphine milligram equivalents administered during mechanical ventilation.

Respiratory Knowledge Portal Computer and Phone Application to Improve Quality of Mechanical Ventilation by Reducing the Number of Ventilator Associated Events, Injury Created by the Ventilator and Unsafe Setting of Alarms.

Ventilator associated events (VAE) is a quality metric defined by 48 hours of stability followed by 48 hours of escalation of ventilator settings within the ICU. VAE have been associated with poor outcomes and increases the cost of care, yet is not easy to avoid. Operationalizing all the standards of care known to improve outcomes of those requiring mechanical ventilation in the critical care environment requires a comprehensive approach. ICU teams are encouraged to follow best practice protocols to help liberate and prevent VAEs. Yet, compliance with protocols in most ICUs is suboptimal for multiple reasons. With the advent of computerized mechanical ventilators capable of streaming data from breath to breath and biomedical integration systems (BMDI) such as Capsule (UTMB's BMDI system), software systems have been developed to help identify variances in the standard of care. Automation in near real-time ventilator data feedback has been shown to reduce the incidences of VAEs. This quality improvement project will leverage Vyaire's Respiratory Knowledge Portal (RKP) to collect and store meaningful data regarding ventilator-associated events (VAE), alarm policy compliance, ventilator weaning, and lung protective analytics. Goals: 1. To collect quality metrics utilizing RKP from patients requiring mechanical ventilation over a 3-4-month period for a retrospective baseline analysis. 2. Provide the RKP tool to the ICU team to determine if the use of RKP's webportal and Messenger Zebra phone app improves quality of mechanical ventilation and outcomes. 3. To determine a return on investment (ROI) for a software system like RKP.

Retrospective Study on Ventilator Weaning Outcomes in Patients With Acute Brain Injury

Invasive mechanical ventilation (IMV) is a life-saving supportive therapy for patients with acute brain injury, which accounted for nearly one-fifth of all mechanically ventilated patients in the intensive care unit (ICU). However, prolonged exposure to IMV is consistently associated with an increased risk of ventilator-related complications and adverse outcomes. Accordingly, alongside the initiation of IMV, timely and safe liberation from ventilator should be considered. Nevertheless, data detailing the weaning process and its associated outcomes in mechanically ventilated patients with ABI remain scarce. To address this gap, the investigators conducted an observational study aimed at characterizing the ventilator weaning process and outcomes in patients with ABI receiving IMV, using the modified WIND classification.

Use of a Physiotherapy Assessment to Predict Extubation Failure in Mechanically Ventilated Patients: the EPIC Assessment

"Weaning from mechanical ventilation is a crucial step in the intensive care unit. Several factors complicate weaning and increase the risk of failure. To predict the success of extubation, the spontaneous ventilation test (T-Tube) remains essential. Despite this, the failure rate is around 10-20%. Failed extubation is not without consequences, since it increases the risk of pneumopathy and mortality. It therefore seems essential to identify potential extubation failures using effective predictive criteria. Several of these predictive criteria have been studied separately in the literature, but are still not widely used in practice. Many studies have sought to identify these predictive criteria, without actually linking them. However, when combined in a single assessment prior to extubation, they could represent a reliable prediction and decision-making aid. In the intensive care unit at Hôpital Bichat Claude Bernard, a team of physiotherapists dedicated solely to this unit carries out a routine EPIC Assessment, combining several criteria, some of which have individually demonstrated their reliability in predicting extubation outcome. Physiotherapists are health professionals working as part of the intensive care team, and are well versed in issues relating to bronchial congestion, respiratory function and muscle strength, whether for breathing or locomotion. Similarly, their involvement in issues relating to swallowing disorders acquired in intensive care gives them an overall view of the patient's ability to protect his or her airway post-extubation. The EPIC Assessment has been designed by them to address these issues. With the help of this assessment, and by following the cut-offs of the various criteria, they link the different criteria making up the EPIC Assessment and communicate a ""favorable"" or ""unfavorable"" opinion for extubation. Our hypothesis is that the EPIC Assessment is, in addition to its interpretation by physiotherapists, a reliable tool for predicting the outcome of extubation."

Neuromuscular Electrical Stimulation in a Patient on Invasive Mechanical Ventilation (MOVCARE)

This clinical study aims to compare the effects of conventional physical therapy alone versus conventional physical therapy combined with neuromuscular electrical stimulation (NMES) in patients admitted to the ICU and undergoing invasive mechanical ventilation. Participants will be randomly assigned to receive either conventional physical therapy or the same therapy plus NMES applied to the lower limbs. The protocol includes muscle-specific stimulation parameters and safety criteria to postpone sessions in cases of clinical instability. The primary goal is to assess whether NMES improves muscle function and recovery in critically ill patients.

Influence of Lung Volume Optimization Maneuver in Ventilated Children on Cardiac Output and Lung Compliance in Children With Congenital Heart Disease Undergoing Surgical Repair

The goal of this randomized interventional clinical trial is to learn if a standardized lung volume optimization maneuver (LVOM) is beneficial in children undergoing biventricular repair of their congenital heart disease (CHD) with cardiopulmonary bypass. Main hypotheses: Does a standardized PEEP-Titration maneuver, to optimize end-expiratory lung volume improve: * cardiac performance * lung function Does it make a difference in: * length of ventilation * ventilation/perfusion mismatch of the lung * need for vasopressor support?

Biomarker and Renal Angina Validation to Assess Heart-Kidney Outcomes After Amino Acid Therapy

The goal of the BRAVE-HEART study is to learn if an amino acid infusion can reduce the risk of developing acute kidney injury after cardiac surgery in children. The main questions it aims to answer are: 1. Does an amino acid infusion decrease the number of participants with acute kidney injury? 2. Does an amino acid infusion decrease the number of days that participants are on a ventilator after cardiac surgery? Researchers will compare amino acids to a placebo (a look-alike substance that contains no drug) to see if amino acids decrease the number of participants with acute kidney injury. Participants will receive an amino acid or placebo infusion for up to 72 hours starting during cardiac surgery and only while in the operating room or the intensive care unit.

Prediction of Extubation Failure: A Multicenter Prospective Observational Study

The investigators intend to collect several variables to predict extubation failure among patients who successfully complete a spontaneous breathing trial, and then develop a scale using simple bedside indicators to predict extubation failure.

Evaluation of Acid-base Disorders and Ventilation Settings in Cardiogenic Shock and Post-cardiac Arrest Patients: Comparison With VentilO Algorithm

This study aims to better understand how mechanical ventilation settings affect patients admitted to the coronary care unit after cardiac arrest or with cardiogenic shock. These patients often require mechanical ventilation, but current guidelines provide limited evidence on the best approach. Improper ventilation settings can lead to acid-base imbalances, such as respiratory acidosis or alkalosis, which may worsen patient outcomes. The retrospective analysis will include 100 adult patients (50 post-cardiac arrest and 50 with cardiogenic shock) who were mechanically ventilated upon admission. The study has two main objectives: Determine how often acid-base disorders occur in these patients and describe their characteristics. Compare the initial ventilator settings chosen by clinicians with those suggested by VentilO, a decision-support algorithm. The investigators will evaluate the potential effect of the VentilO recommendations on the first arterial (or capillary) blood gases compared to the real settings. This information will help refine the algorithm and guide future research on improving ventilation strategies for critically ill cardiac patients. Participation does not involve any intervention, as the study uses existing medical records.

A Retrospective Clinical Study of Metabolic Status and Response to Nutritional Therapy in Patients With Mechanical Ventilation

This study used a retrospective cohort study based on Multi-time longitudinal monitoring data were used to analyze the correlation mechanism between the dynamic evolution characteristics of nutrition-related biochemical indicators and individualized nutritional intervention in patients with mechanical ventilation. The inflammation-nutrition interaction model was constructed to correct the interference effect of inflammatory microenvironment on nutritional status assessment, so as to provide a basis for further achieving precision nutritional support.

Metabolic Response to Supine Physiotherapy in Mechanically Ventilated ICU Patients

Critically ill patients who require mechanical ventilation frequently experience rapid loss of muscle mass and physical function during their stay in the intensive care unit (ICU). As part of standard care, physiotherapy and limb mobilization exercises are commonly provided, even in patients who are sedated and confined to bed in a supine position. However, the actual physiological and metabolic intensity of these routine physiotherapy interventions is poorly understood, and current prescriptions are largely based on clinical judgment rather than objective measures of patient effort or tolerance. Oxygen consumption (VO₂) is a direct indicator of metabolic demand and physiological workload. In mechanically ventilated patients, indirect calorimetry integrated into the ventilator allows continuous measurement of VO₂ and carbon dioxide production without adding invasive procedures. While indirect calorimetry is routinely used to individualize nutritional support in the ICU, its potential role in quantifying the metabolic cost of physiotherapy interventions has been scarcely explored. The aim of this prospective observational study is to quantify the acute metabolic response to a standardized session of supine physiotherapy in adult critically ill patients receiving invasive mechanical ventilation. During routine physiotherapy sessions performed as part of usual care, oxygen consumption will be continuously measured using indirect calorimetry integrated into the ventilator circuit. Each session will include a baseline resting period, the physiotherapy intervention itself, and a post-intervention recovery period, allowing patients to act as their own controls. Physiotherapy sessions will consist of passive limb mobilization in deeply sedated patients and passive or active-assisted mobilization in patients who are awake or lightly sedated and able to cooperate. The primary outcome will be the change in oxygen consumption during physiotherapy compared with baseline rest. Secondary analyses will describe the total metabolic load of the session, peak oxygen consumption, and the time required for oxygen consumption to return toward baseline levels after the intervention. Basic cardiorespiratory variables, such as heart rate, blood pressure, oxygen saturation, and ventilatory parameters, will also be recorded to assess physiological stability and tolerance. By objectively characterizing the metabolic cost of common supine physiotherapy interventions, this study aims to improve understanding of the physiological demands imposed on mechanically ventilated ICU patients. The results may help inform safer and more individualized physiotherapy prescriptions in critical care, supporting a more objective approach to dosing rehabilitation based on patients' real metabolic responses rather than solely on activity type or sedation level.

Effect of Post-suction Recruitment on Lung Volume in Mechanically Ventilated ICU Patients

Patients who are intubated and mechanically ventilated in the intensive care unit (ICU) require repeated endotracheal suctioning to remove airway secretions. Although this procedure is necessary, it can cause a temporary collapse of lung units (alveolar derecruitment), leading to a decrease in lung volume and impaired oxygenation. A recruitment maneuver consists of briefly applying a higher airway pressure after suctioning in order to reopen collapsed lung areas and restore lung volume. However, the clinical benefit of performing a recruitment maneuver systematically after suctioning remains uncertain. This study aims to evaluate whether performing a recruitment maneuver immediately after closed-circuit endotracheal suctioning improves lung volume compared with suctioning alone. Lung volume will be assessed using electrical impedance tomography (EIT), a non-invasive bedside imaging technique that allows real-time monitoring of lung aeration. In a randomized crossover design, each patient will undergo two suctioning procedures: one followed by a recruitment maneuver and one without, in a random order. The main outcome will be the change in end-expiratory lung volume 15 minutes after suctioning. The results may help optimize ventilatory care in mechanically ventilated ICU patients.

Amnioinfusion's Protective Effects on Respiratory and Longitudinal Pediatric Outcomes After Intrapartum Thick Meconium Exposure

Thick meconium in the amniotic fluid occurs in about one out of seven pregnancies and increases the chance that a newborn may have breathing problems after birth. These problems can include the need for oxygen, breathing support, admission to the neonatal intensive care unit (NICU), or, in severe cases, meconium aspiration syndrome or persistent pulmonary hypertension. Although amnioinfusion or placing sterile fluid into the uterus during labor was previously studied as a way to reduce these complications, earlier research had major limitations. Past studies included all types of meconium, used different fluid types and temperatures, had inconsistent protocols, and did not measure biomarkers of inflammation or look at long-term outcomes. As a result, it is still unclear whether a modern, standardized approach to amnioinfusion can meaningfully improve newborn health when the meconium is truly thick. The PEARL Trial is a randomized clinical trial designed to answer this question. The study will enroll pregnant individuals at or beyond 36 weeks of gestation who develop thick meconium-stained amniotic fluid, confirmed using a simple, objective measurement ("meconium-crit"). Participants will be randomly assigned to receive either: Warm lactated Ringer's (LR) amnioinfusion through an intrauterine pressure catheter (IUPC), following a standardized protocol, or standard care without amnioinfusion. The main goal is to determine whether warm LR amnioinfusion reduces short-term breathing problems in newborns. The study also collects umbilical cord blood at birth to evaluate markers of inflammation and potential brain injury, which may help explain why some infants develop complications. Families will also be contacted when their child is 12 months old to complete a developmental questionnaire that is widely used in pediatric practice. By using a clear definition of thick meconium, a warm LR infusion protocol, fidelity checklists, and long-term follow-up, this trial aims to provide high-quality evidence to guide care in labor and delivery units nationwide.

Turkish Validity and Reliability of the Behavioral Indicators of Pain Scale(ESCID)

A significant proportion of patients hospitalized in intensive care units (ICUs) require mechanical ventilation, and the treatments applied during this process may cause pain. Pain is defined as an unpleasant sensory and emotional experience associated with actual or potential tissue damage. Although it is associated with delirium and agitation, pain is often an overlooked symptom in ICU patients, and a large proportion of mechanically ventilated patients continue to experience moderate to severe pain. The most common type of pain in critically ill patients is nociceptive pain, which may result from invasive procedures such as tracheal intubation, catheter insertion, aspiration, wound care, and patient repositioning. Additionally, the noisy and unfamiliar ICU environment and patients' inability to express themselves may further increase the perception of pain. Regular assessment of pain is associated with many positive outcomes, including more effective pain management, appropriate use of analgesic and sedative medications, and shorter duration of mechanical ventilation and ICU stay. Although self-reporting of pain is considered the gold standard, many patients receiving mechanical ventilation are unable to communicate their pain. Therefore, various behavioral pain assessment scales are used to evaluate pain in ICU patients. One of these tools is the Behavioral Indicators of Pain Scale (Escala de Conductas Indicadoras de Dolor - ESCID), which was developed to assess pain in critically ill adult patients receiving mechanical ventilation who are unable to communicate. However, a Turkish version of this scale has not yet been developed. Therefore, the aim of this study is to translate the ESCID scale into Turkish, perform its cultural adaptation, and test the validity and reliability of the Turkish version.

The ED-AWARENESS-2 Trial

The investigators will screen all mechanically ventilated ED patients for study eligibility and will enroll all consecutive patients satisfying inclusion and exclusion criteria. The study design is a pragmatic, multicenter, stepped wedge cluster randomized trial, enrolling at five sites over a 3-year period, divided into six time periods of six months. Prior to the study, each site will be randomized to their position within the design. One site will cross to the intervention period (i.e. succinylcholine as default neuromuscular blocker) every six months from the 2nd to 6th time period. Cluster order will be determined by computer-based randomization. To begin, each site will be exposed to control conditions; by the end of the study, each site will be exposed to intervention conditions. Patients in the control phase will receive usual care, and this phase will be entirely observational. After six months, a site will enter a 2-month transition phase. In this phase, the investigators will implement the intervention, similar to how they have implemented other ED-based interventions for mechanically ventilated patients. The investigators will engage and educate ED clinicians on the importance of AWP prevention and the study objectives. The intervention framework relies on the use of "nudges", without restricting choice. The use of neuromuscular blockers (i.e. "paralytic" medications) is already part of routine care in the ED in order to facilitate endotracheal intubation and initiation of mechanical ventilation for patients with acute respiratory failure. The two most common neuromuscular blockers used in the ED are succinylcholine and rocuronium. The preliminary data show a strong association between rocuronium (a longer-acting neuromuscular blocker) use and AWP. Therefore, this study aims to improve care by educating caregivers on AWP and the use of the neuromuscular blockers, which are already routinely used, and studying that process in a rigorous fashion. The default neuromuscular blocker in the intervention phase will be succinylcholine. Succinylcholine will be the default over rocuronium because: 1) it has safely been the default neuromuscular blocker of choice in the ED for \>40 years ; 2) its 5-minute duration of action greatly reduces AWP risk; 3) the preliminary data regarding an increased risk of AWP with rocuronium and 4) ED rocuronium use has increased despite no patient-centered studies showing benefit over succinylcholine. Passive alerts (i.e. graphics, pocket cards) will also be strategically placed in the ED, and active alerts will be used as reminders before every nursing shift (i.e. "the huddle"). After this transition phase, the site will begin the intervention phase, and patients will again receive clinician-directed care, just after the intervention.

Prospective Multicentre Mixed Methods Study to Explore Extubation Practices and Respiratory Outcomes in Extremely Preterm Neonates.

The purpose of this observational study is to learn about neonatologists' perceptions of extubation readiness and extubation and reintubation practices in extremely preterm infants in the first 2 weeks of life using prospective qualitative and quantitative data. Actual extubation readiness is defined as successful extubation, defined as no reintubation in the 7 days following extubation. Key research questions are: How do clinicians assess extubation readiness in this population? Does this assessment correlate with actual extubation success? What factors (reasons, clinical status, ventilatory parameters) are associated with extubation readiness? Patients born before 28 weeks gestational age and admitted to the neonatal intensive care unit (NICU) within the first 24 hours are be included. The attending physician will complete a prospectively administered questionnaire with open-ended and multiple-choice questions to daily assess the decision and rationale for extubation or non-extubation of patients mechanically ventilated during the first 15 days of life. Patient characteristics, respiratory outcomes, and mortality will be recorded until the end of hospitalisation and/or definitive weaning from any ventilatory support or supplemental oxygen.

Microbiome-guided Prophylaxis to Reduce Ventilator-Associated Pneumonia in Intensive Care Units: A Pilot Randomized Controlled Trial

Ventilator-associated pneumonia (VAP) remains the most common hospital-acquired infection worldwide, affecting up to 40% of mechanically ventilated patients and contributing to increased morbidity, prolonged hospital stays, and high mortality rates. Standard prevention strategies rely on VAP prevention "bundles", which focus on general supportive care measures such as head-of-bed elevation, sedation interruption, and oral care. While these measures reduce some risk, they do not specifically target the underlying microbial mechanisms driving VAP. Emerging evidence supports the use of inhaled antibiotic (iABx) prophylaxis to suppress or eliminate airway pathogens. Several randomized controlled trials have shown that inhaled antimicrobials can reduce the incidence of VAP. However, the effectiveness of this approach is inconsistent when applied to all ventilated patients. Studies indicate that the greatest benefit occurs when inhaled antimicrobials are targeted toward patients with airway colonization by specific VAP pathogens. Traditional airway microbiome diagnostics have been a major barrier to implementing targeted prophylaxis because they are slow, costly, and require advanced expertise. Recently, a novel diagnostic method-ON-Time rapid microbiome sequencing-has been developed, offering accurate, cost-effective, and rapid (approximately 4.2 hours) results that can identify key VAP pathogens within the airway microbiome of ICU patients such as Enterobacteriaceae organisms, Pseudomonas spp., Acinetobacter spp., Stenotrophomonas maltophilia, Staphylococcus aureus, and others. The ability to define the airway microbiome of ICU patients including whether they harbour potential VAP pathogens provides a unique opportunity to tailor prophylactic antibiotics in a personalized and timely manner. Thus, microbiome-guided prophylaxis represents a novel precision medicine approach to preventing VAP by selecting the right patient. This pilot trial aims to test the feasibility of implementing such an approach to prevent VAP in critically ill patients.

Relationship Between the Level of Positive End-expiratory Pressure and Venous Congestion During Acute Respiratory Distress Syndrome.

The main objective is to assess the effect of increased PEEP on echo-Doppler venous congestion in ARDS patients at two PEEP levels, by grading congestion in each venous flow (suprahepatic, renal, portal) as "absent," "moderate," or "severe," and also calculating the VExUS score.

Impact of PEEP on Respiratory Effort During Assisted Ventilation

Assisted mechanical ventilation is widely used to preserve diaphragmatic activity and improve lung aeration in patients with acute respiratory failure. However, during assisted ventilation, excessive inspiratory effort may develop and contribute to lung injury, diaphragmatic overload, and patient self-inflicted lung injury. Optimizing ventilator settings to modulate respiratory effort therefore represents a major physiological and clinical challenge. Positive end-expiratory pressure (PEEP) is a key determinant of lung recruitment and respiratory system mechanics and may influence inspiratory effort by modifying lung volume, compliance, and respiratory drive. Despite its widespread use, PEEP titration in clinical practice is still mainly guided by oxygenation parameters, while its direct effects on inspiratory effort during assisted mechanical ventilation remain insufficiently characterized. This physiological randomized crossover study aims to evaluate the effect of four predefined levels of positive end-expiratory pressure (0, 5, 10, and 15 cmH₂O) on the respiratory system and inspiratory effort in adult patients receiving assisted mechanical ventilation. Patients will be exposed to each PEEP level in randomized order, with stabilization and washout periods between conditions, while ventilatory support settings other than PEEP are kept constant.

Flow-Controlled Versus Volume-Controlled Ventilation in Bariatric Surgery

This prospective trial aims to compare the effects of flow-controlled ventilation (FCV) and volume-controlled ventilation (VCV) on intraoperative airway pressures and oxygenation in bariatric surgery under general anesthesia. Obesity is associated with altered respiratory mechanics, reduced functional residual capacity, and increased airway pressures, making the selection of an optimal ventilation strategy particularly important in this patient population. Adult patients aged 18-65 years with a body mass index ≥30 kg/m² and American Society of Anesthesiologists (ASA) physical status II-III will be allocated to receive either FCV or VCV as part of routine intraoperative mechanical ventilation. Ventilatory parameters, including peak and plateau airway pressures, pulmonary compliance, will be recorded at predefined intraoperative time points. The primary endpoint of the study is the PaO₂ value measured at the 20th minute under an FiO₂ of 0.8-1.0. By providing comparative data on respiratory mechanics and oxygenation, this study aims to contribute to the identification of lung-protective ventilation strategies and to optimize intraoperative ventilatory management in bariatric surgery.

Optimizing Pain Treatment in Children On Mechanical Ventilation

In this clinical trial, investigators want to learn more about using non-opioid pain medications for children with acute respiratory failure. Right now, doctors give these children opioids to help with pain while they are on the ventilator, but investigators don't know if this is the best way to manage their pain. Even with strong doses of opioids, more than 90% of these children still feel pain. Other pain medicines, like acetaminophen (also called Tylenol) and ketorolac (also called Toradol), are available but aren't commonly used because we don't know if they help. The goal of this clinical trial is to test if acetaminophen and/or ketorolac can improve pain control and reduce the need for stronger pain medications (opioids) in these children. To learn more about this, participants will be randomly placed in one of four study treatment groups. This means that a computer will decide by chance which group each participant is in, not the doctors running the study. Each group will receive a combination of intravenous acetaminophen, ketorolac or a harmless substance called a placebo. In this clinical trial, placebos help investigators see if the actual medications (acetaminophen and ketorolac) work better than something that doesn't contain medicine. By comparing participants who get the real medicine with those who get the placebo, investigators can find out if these medications effectively decrease pain.

Effects of PERMISSive Lung-protective Ventilation on Outcome in Critically Ill Invasively Ventilated Patients

RATIONALE Lung-protective ventilation using a lower respiratory rate (RR) is an appealing strategy to reduce ventilation intensity, which may require permissive hypercapnia. However, the feasibility and safety of this so-called 'permissive lung-protective ventilation' must be investigated, before conducting a large randomized clinical trial to evaluate its effectiveness on patient-centered outcomes. OBJECTIVE To study the feasibility and safety of permissive lung-protective ventilation in adult critically ill patients receiving invasive ventilation for acute hypoxemic respiratory failure, and to inform the design of a future randomized clinical trial in this patient population. HYPOTHESIS Permissive lung-protective ventilation is a feasible and safe ventilation strategy. STUDY DESIGN Multicenter, randomized clinical pilot trial. STUDY POPULATION Critically ill patients, aged \> 18 years, intubated for acute hypoxemic respiratory failure, and expected to receive ventilation for \> 24 hours. METHODS Patients are randomized to permissive lung-protective ventilation wherein RR is stepwise reduced, or to conventional lung-protective ventilation. OUTCOME MEASURES The primary endpoint is feasibility, assessed by the difference in respiratory rate (RR) between the two groups, from the start of mechanical ventilation until first extubation. Secondary endpoints include protocol compliance and feasibility of collecting data, and safety, assessed by the occurrence of unacceptable hypercapnia and hypoxemia and the incidence of ventilator-associated complications SAMPLE SIZE To estimate the appropriate sample size for this pilot study, we considered the primary feasibility endpoint of detecting a difference in the respiratory rate (RR). Assuming an expected mean difference in RR of 7.5, based on previous studies \[1, 2\], with an SD of 10, a power of 90% and an alpha of 0.05, with a drop-out rate estimated at 10%, a two-tailed t-test was used. The required sample size is 84 patients (42 patients per group). NATURE AND EXTENT OF THE BURDEN AND RISKS ASSOCIATED WITH PARTICIPATION, BENEFIT AND GROUP RELATEDNESS Ventilation with a lower RR may require permissive hypercapnia, which, when kept within safe limits, is safe. In current daily practice, there is no guidance in setting RR; consequently, RR varies widely across patients and is often set high. This pilot study compares two forms of lung-protective ventilation, both considered standard care in current ICU practice. The control group receives conventional ventilation with low tidal volumes and high RR to maintain normal PaCO₂ and pH. The intervention group, permissive ventilation, uses a lower RR to reduce mechanical power, accepting mild hypercapnia and acidosis. Permissive ventilation is most often reserved for patients with severe lung conditions, where ventilator settings are more complex and ventilation intensity is high. In these patients, permissive ventilation is considered safe, and may even be beneficial. We aim to evaluate this strategy more broadly in critically ill patients. The collection of demographic, ventilation and outcome data causes no harm to patients. Blood is drawn for arterial blood gas analysis, but this is also part of standard care.