Clinical Research Directory

Predictors of Clinically Relevant Hypotension and Hypoxemia During Propofol-Based Diagnostic Gastrointestinal Endoscopy

This prospective observational cohort study will evaluate the incidence and independent predictors of clinically relevant hypotension and hypoxemia during propofol-based diagnostic gastrointestinal endoscopy in adult patients at a tertiary referral hospital in Vietnam. Participants undergoing diagnostic upper gastrointestinal endoscopy, colonoscopy, or combined diagnostic procedures with propofol administration will be followed from pre-procedure assessment through the early recovery period. The study will assess demographic, clinical, airway, procedural, and sedation-related variables associated with clinically relevant cardiopulmonary adverse events.

HFNC Versus Microstream Advance Nasal Cannula for Oxygenation During ERCP

Endoscopic retrograde cholangiopancreatography (ERCP) procedures are commonly performed under deep sedation and are associated with a risk of hypoxemia, particularly in prone or semi-prone positions. High-flow nasal cannula (HFNC) therapy may improve oxygenation by delivering heated and humidified oxygen at high flow rates, while the Microstream Advance nasal cannula provides simultaneous nasal oxygen delivery and oral oxygen insufflation. This prospective randomized study aims to compare the effectiveness of HFNC and Microstream Advance nasal cannula in maintaining oxygenation during ERCP procedures. Patients undergoing ERCP will be randomized into two groups receiving either HFNC or Microstream Advance nasal cannula oxygen support during sedation. The primary outcomes are the incidence of desaturation and oxygen reserve index (ORi) measurements during the procedure. Secondary outcomes include time to achieve target ORi levels, respiratory complications, and procedure-related adverse events.

POM vs HFNC for Hypoxemia Prevention in Children

Upper gastrointestinal endoscopy is a commonly performed diagnostic and therapeutic procedure in children, allowing evaluation of the esophagus, stomach, and duodenum, as well as interventions such as biopsy, foreign body removal, and polypectomy. Sedation is routinely used, often at greater depths than for standard examinations. Due to anatomical and physiological differences, including smaller airway diameter, higher oxygen consumption, and lower functional residual capacity, pediatric patients are at higher risk of airway obstruction, hypoxemia, and hypoventilation compared to adults. The passage of the endoscope through the mouth further limits airway access and increases the risk of desaturation. Oxygenation during pediatric endoscopy is typically supported using nasal cannulas, high-flow systems, or procedural oxygen masks (POM™). This pilot randomized study aims to compare POM™ and high-flow nasal cannula in preventing hypoxemia during sedated pediatric upper gastrointestinal endoscopy, contributing evidence for safer sedation and airway management practices in children.

Effect of Different Bed Head Angles on Intraoperative Hypoxemia in Patients Undergoing Painless Gastroenteroscopy: A Prospective Randomized Controlled Study

Abstract: Objective: This study aimed to investigate the effect of different bed angles (0° vs. 15°) on the incidence of intraoperative hypoxemia in patients undergoing gastroscopy and colonoscopy. A prospective randomized controlled trial was conducted to evaluate the impact of patient positioning on respiratory safety, providing evidence for individualized anesthesia management. Background: With the increasing popularity of painless gastrointestinal endoscopy, hypoxemia has become a major safety concern in anesthesia management, particularly in elderly and obese patients. Studies have shown that the incidence of hypoxemia can exceed 26%, highlighting the importance of optimizing respiratory safety during anesthesia. Methods: A total of 400 patients scheduled for painless gastrointestinal endoscopy were recruited and randomly assigned to a control group (0° left lateral position) or an experimental group (15° left lateral position). Baseline data were recorded preoperatively. Intraoperative vital signs were monitored, and the occurrence of hypoxemia and other complications was documented. Data were collected and processed in a blinded manner, followed by statistical analysis using SPSS 26.0.

Investigation of Skin Pigmentation Effect on Performance of Masimo Pulse Oximetry (INSPIRE)

The objective of this study is to evaluate the performance of Masimo RD SET® SpO2 sensors in subjects with light and dark skin pigmentation in the intensive care therapeutic area.

The Role of Ultrasonographic Tracheal Measurements in Predicting Hypoxemia During Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration

Bronchoscopic procedures performed under endobronchial ultrasound (EBUS) guidance are widely used minimally invasive diagnostic methods for the evaluation of mediastinal lymph nodes. Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration (EBUS-TBNA) is an indicated procedure for the diagnosis, staging, and histopathological characterization of primary or metastatic tumors. The procedure is generally performed under moderate or deep sedation to enhance patient comfort and optimize procedural success. Deep sedation has been shown to be a safe and effective approach in terms of respiratory complications in both younger and elderly patients. However, hypoxemia may develop during EBUS procedures due to mechanisms such as mechanical airway obstruction, sedation-related ventilatory depression, and ventilation-perfusion mismatch. A decrease in oxygen saturation is frequently observed during bronchoscopic procedures, with reported rates of up to 94%. Studies have also reported a hypoxemia rate of approximately 25% during EBUS, even with the use of a nasopharyngeal oxygen cannula. Therefore, maintaining adequate oxygenation throughout the procedure is of critical importance. In patients receiving sedation under spontaneous respiration, oxygen support is typically provided via low-flow systems such as nasal cannulae, which can generally deliver flows of up to 15 L/min. It has been reported that a fiberoptic bronchoscope occupies approximately 10% of the tracheal cross-sectional area and about 15% at the level of the cricoid ring, leading to partial obstruction. EBUS endoscopes have a larger outer diameter and, in addition, may exert more pronounced negative effects on respiratory mechanics due to the balloon mechanism used. The outer diameter of EBUS bronchoscopes typically ranges between 6.2 and 6.7 mm, mechanically occupying a significant portion of the tracheal lumen. This may restrict tracheal airflow, leading to partial obstruction and consequently predisposing to hypoxemia. Therefore, identifying objective anatomical predictors that can predict the development of hypoxemia is of clinical importance. However, to the best of our knowledge, no study in the literature has statistically investigated the relationship between tracheal measurements and hypoxemia occurring during EBUS. In this study, the investigators aim to investigate the relationship between pre-procedural tracheal diameter measured by ultrasonography (USG) and the EBUS outer diameter/tracheal diameter ratio (airway occupancy ratio) with the development of hypoxemia during the procedure in patients undergoing EBUS-TBNA. Additionally, it is aimed to determine the optimal tracheal diameter cutoff value that may predict the development of hypoxemia. Study Design and Patient Population This study will be conducted in accordance with the Declaration of Helsinki and will be carried out at SBÜ Ankara Atatürk Sanatoryum Training and Research Hospital after obtaining approval from the institutional ethics committee. The study is planned as a prospective observational cohort study. Adult patients scheduled to undergo EBUS-TBNA will be included. The following parameters will be recorded: * Age * Sex * Body mass index (BMI) * FEV1 value * Baseline SpO₂ * Lowest recorded SpO₂ * Systolic/diastolic/mean arterial blood pressure and heart rate measured at 10-minute intervals during the procedure * Sedative drug doses * Procedure duration * Tracheal diameter measured by ultrasonography (USG) * Airway occupancy ratio (EBUS outer diameter / narrowest tracheal diameter measured by USG) * Duration and total number of hypoxic episodes during the procedure * Requirement for airway interventions (jaw thrust, mask ventilation, intubation, etc.) * Whether nasal oxygen flow was increased in case of hypoxemia, and if so, by how many L/min * Presence of cough, hiccups, secretions requiring aspiration, bronchospasm, and procedure-related bleeding * Whether the procedure was interrupted

Oxygen Targets in Acute Heart Failure With Pulmonary Congestion

This investigator-initiated, prospective, randomized, blinded, multi-center, controlled trial will investigate the effect of a restrictive vs. liberal oxygenation-strategy in patients hospitalized with acute heart failure with pulmonary congestion. Patients will be randomized 1:1 in the emergency department to either liberal or restrictive oxygenation after providing informed written consent. 1. Liberal oxygenation group = SpO2 target of 96%. 2. Restrictive oxygenation group = SpO2 target of 90%. The allocation will be concealed through the use of an oxygen-delivery robot, termed O2MATIC. The study will include 122 patients.

Dexmedetomidine vs Propofol in High-Risk ERCP Patients

ERCP requires deep sedation due to pain and discomfort, but propofol-commonly used with opioids-often causes respiratory and cardiovascular complications, especially in elderly or high-risk patients. Dexmedetomidine offers sedation without respiratory depression but may lower blood pressure and heart rate. Current monitoring often relies only on SpO₂, while capnography and the Integrated Pulmonary Index (IPI) provide earlier detection of respiratory events but are underused in ERCP studies. This study compares dexmedetomidine and propofol in high-risk ERCP patients, focusing on respiratory and hemodynamic effects, propofol consumption, recovery, and discharge times. The hypothesis is that dexmedetomidine will cause fewer adverse respiratory and hemodynamic effects.

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.

Rebreathing-induced Hypoxia and Glucose Levels

The aim of this research project is to determine the effect of repeated maximal voluntary apneas on glucose uptake during an oral glucose tolerance test in healthy individuals, individuals with prediabetes and patients with type 2 diabetes.

Effect of High-Flow Nasal Cannula Oxygen Therapy on Hypoxemia in Pediatric Sedated Bronchoscopy

Due to children's lower oxygen reserves and higher oxygen consumption, sedation can easily lead to respiratory adverse events such as hypoxemia. It has been reported that the incidence of hypoxemia during pediatric bronchoscopy is high, highlighting that hypoxemia in pediatric painless bronchoscopy is an urgent problem requiring a solution. High-flow nasal cannula (HFNC) oxygen therapy delivers heated and humidified breathing gas with a precisely controllable oxygen concentration, at flow rates exceeding the patient's peak inspiratory flow, directly via unsealed nasal prongs. It is a simple, comfortable, effective, and non-invasive respiratory support method that has been widely adopted in clinical practice. However, the effectiveness of HFNC in pediatric sedation remains unclear. Therefore, this multicenter randomized controlled trial aims to evaluate whether HFNC can effectively reduce the occurrence of hypoxemia during sedated bronchoscopy in pediatric patients.

Effect of Hyperoxia or Hypoxemia on the Incidence of Delirium in Patients After Cardiac Surgery

Our goal was to study the effect of hyperoxia or hypoxemia on the incidence of delirium in patients after cardiac surgery.

The Role of Acetazolamide in Mitigating Inflammation and Innate Immune Activation at High Altitude

High altitude travel can lead to inflammation in the body and activation of innate immune cells. The investigators' prior research demonstrates that 1 to 3 days at 3800 m elevation leads to increased expression of genes in blood cells that code for proteins that signal cell damage (damage associated molecular patterns (DAMPs)), cell receptors involved in innate immune responses, as well as increases in monocyte and neutrophil cells which promote inflammation. This study will investigate the potential mechanisms underlying these effects using the drug Acetazolamide, a carbonic anhydrase inhibitor which is known to reduce symptoms of Acute Mountain Sickness.

Lung Ultrasound Score and Postoperative Pulmonary Complications in Major Non-Thoracic Surgery

This prospective observational cohort study aims to evaluate the predictive value of perioperative lung ultrasound (LUS) score in determining early postoperative oxygen requirement and pulmonary complications in patients undergoing major non-thoracic surgery. Postoperative pulmonary complications remain a significant cause of morbidity and mortality in surgical patients. Lung ultrasound is a non-invasive, bedside imaging modality that allows real-time assessment of lung aeration and pathology. This study will investigate the association between perioperative LUS score and early postoperative respiratory outcomes, including oxygen requirement and pulmonary complications.

Titrated Ambulatory Oxygen in Fibrotic ILD and COPD With Isolated Exertional Hypoxemia

Fibrotic forms of interstitial lung disease (ILD) and chronic obstructive pulmonary disease (COPD) are chronic lung disease which often affect how well oxygen can get from the lungs into the blood. Low blood oxygen levels often leads to shortness of breath which can affect patients' activity levels and quality-of-life. Many people with fibrotic ILD and COPD only have low oxygen levels when they are walking or exercising. Oxygen that is only used for walking or exercise is called ambulatory oxygen therapy (AOT). Laboratory studies suggest that AOT improves shortness of breath and exercise ability. However, real-world studies of AOT have not shown similar results. AOT can be given to patients through different types of equipment, most commonly oxygen tanks or portable oxygen concentrators (POCs). While previous studies have suggested that AOT does not significantly improve patients' breathing or activity in the real-world, these studies most often gave all participants the same amount of oxygen with the same device. However, patients with ILD and COPD often have very different oxygen needs during exercise, and POCs and oxygen tanks are very different in how oxygen is administered. This trial will test the feasibility of a study to determine whether real-world activity, symptoms, and quality-of-life are different with the use of different oxygen equipment when oxygen therapy has been adjusted to meet each participants' oxygen needs. A total of 24 participants (12 with fibrotic ILD and 12 with COPD) who only have low oxygen levels with activity will be randomly assigned to 2-week periods using either no oxygen therapy or oxygen delivered by oxygen tanks or POC. This trial will provide preliminary data to support a larger clinical trial to further test how different AOT equipment titrated to meet individual patients' needs may affect real-world outcomes in people with ILD and COPD.

Effects of Oxygen Supplementation During the 6-Minute Walk Test in Chronic Respiratory Failure or Exertional Hypoxemia

The aim of this multicenter crossover trial is to describe the effect of adding a therapeutic dose of exertional oxygen therapy, in terms of exercise performance, gas exchange, heart rate, symptoms perception and subjective easiness of performance, in a cohort of subjects hospitalized in specialized pulmonary rehabilitation centers with a diagnosis of chronic respiratory failure and/or exertional hypoxemia due to chronic obstructive pulmonary disease or interstitial lung disease. Researchers will compare the walking performance during 6-minute walk test performed with the liters of oxygen administered as prescribed at rest (for patients with chronic respiratory failure) or in room air (for patients with exertional hypoxemia only), to the performance during a 6-minute walk test performed with the double the flow rate prescribed at rest, or with 2 L/min for patients with exertional hypoxemia only. The two tests will be performed in random order, at least 3 hours apart and no later than 24 hours apart from each other. The main outcome will be the difference between the distance walked in the two 6-minute walk test in the two conditions. Furthermore, will be also collected and compared: the oxygen saturation and heart rate every minute, the initial and final dyspnea and fatigue, as assessed by Borg scale, and the easiness of performance through a dedicated questionnaire. The estimated sample size will be 114 patients. This study will provide some basis for a more accurate prescription of exercise-related oxygen therapy, offering insights into the phenotype of patients who may derive the greatest benefit from this intervention. It will also stimulate discussion regarding the optimal timing and dosing of oxygen administration during exertion in patients with respiratory failure.

Real-Time End-Tidal Carbon Dioxide Monitoring for Early Warning of Hypoxemia in Painless Gastrointestinal Endoscopy

Using Capnography for Safer Sedation in Painless Gastrointestinal Endoscopy Why is this study important? For procedures like painless gastroscopy and colonoscopy, patients receive sedation to ensure comfort. However, traditional monitoring (like checking heart rate and blood oxygen levels) can only detect breathing problems after they have already caused a drop in oxygen. This delay can be risky, especially for elderly patients whose breathing function is naturally weaker. This study looks at a better way to monitor patients. What is the new method? This study focuses on a technology called real-time end-tidal carbon dioxide (ETCO₂) monitoring, also known as capnography. It is a simple, non-invasive device that continuously measures the carbon dioxide a patient breathes out. This provides an early warning system for doctors, alerting them to breathing issues (like a pause in breathing or an airway blockage) much sooner than traditional monitors can. What did the study find? Based on extensive research and clinical experience both in China and internationally (including the US and Europe), integrating ETCO₂ monitoring into painless digestive endoscopy procedures leads to significant improvements in patient safety: * Reduces Risks: It can decrease the occurrence of hypoxemia (dangerously low oxygen levels) by up to 31%. * Early Detection: It detects breathing problems 17.6 times more often than relying on traditional observation alone, giving anesthesiologists crucial extra time (often seconds) to intervene before a patient's oxygen drops. * Safer for Everyone: It is particularly effective in protecting high-risk groups, such as elderly patients and those with mild obesity. * Better Outcomes: It helps reduce postoperative complications like nausea and vomiting, and can lead to faster recovery from anesthesia. Value for Patients, Families, and Providers: * For Patients \& Families: This technology means a safer, more comfortable procedure with a lower risk of breathing complications. It provides peace of mind knowing your breathing is being watched continuously and carefully. * For Healthcare Providers: It offers a clear, real-time picture of a patient's breathing status. This supports quicker, more confident clinical decisions, reduces workload, and helps establish a standardized, quantifiable safety protocol for non-operating room anesthesia, aligning with the World Health Organization's goals for safer surgery.

Prevention of Desaturations Using Positive Airway Pressure or Capnometry During ERCP

Although sedation during endoscopy is sufficiently safe, desaturations are among the most common side effects of endoscopic retrograde cholangiopancreatography (ERCP) procedures, occurring in approximately 20-30% of cases. Sedation during endoscopy increases the complication rate, and a significant proportion of severe and serious side effects are respiratory/airway-related. However, most patients require sedation to complete the procedure and achieve adequate outcomes during therapeutic ERCP. Therefore, improved measures to increase ERCP safety are needed. Since the demand for anesthesia in many centers already (far) exceeds current capacities, performing additional ERCPs under general anesthesia is not an option. Innovative ways to improve cardiorespiratory monitoring or respiratory management during ERCP could offer a solution without significantly increasing costs. Fortunately, dedicated devices for respiratory management and/or monitoring during endoscopy already exist, but their impact on improving patient safety has not yet been well studied. Therefore, the aim of this prospective, randomized, open-label, non-interventional study is to investigate the effects of non-invasive airway management and respiratory monitoring devices on desaturation rate during endoscopic retrograde cholangiopancreatography. For this purpose, 288 adult patients (male and female, 18+ years) undergoing ERCP for medical reasons will be enrolled and randomized to one of three groups: (i) airway management using positive airway pressure (PAP group), (ii) additional monitoring using capnography (capnography group), and (iii) a control group with standard monitoring/treatment (i.e., 2 L O2/min via nasal cannula) (control group). Patients are monitored during the ERCP procedure according to medical standards (non-invasive blood oxygen saturation measurement = SpO2, regular non-invasive blood pressure measurement, pulse), and all desaturation events (defined as an SpO2 \<85% for any duration according to guidelines) are recorded and treated according to guideline recommendations (the studies do not specify any measures for the (non-)treatment of desaturations). After the procedure, patients are followed (passively) for 30 days (review of medical records) to record late complications. The main outcome parameter is the comparison of the desaturation rate in the PAP versus the control group.

Combination of COMBO Endoscopy Oropharyngeal Airway and HFNC Oxygenation in Sedated Gastrointestinal Endoscopy for Morbidly Obese Patients

Hypoxaemia during sedated gastrointestinal endoscopy exceeds 40 % in morbidly obese (BMI ≥ 35 kg m-²) patients. High-flow nasal cannula alone often fails because of persistent airway collapse. A recent innovation in this domain is the COMBO Endoscopy Oropharyngeal Airway-a multifaceted device that encompasses capnography monitoring, bite block , oxygenation support, and oropharyngeal airway management.The purpose of this study is to investigate whether the combination of the COMBO Endoscopy Oropharyngeal Airway and High-Flow Nasal Cannula oxygenation reduces the incidence of hypoxemia in this population.

Recovery Hypoxemia After Sedated Upper Gastrointestinal Endoscopy

Sedation during upper gastrointestinal endoscopy may lead to respiratory events not only during the procedure but also in the early recovery period. Although most hypoxemic episodes are considered transient, their frequency, duration, and clinical consequences during recovery remain insufficiently defined. This prospective observational study aims to evaluate the incidence, duration, and clinical impact of recovery-period hypoxemia following sedated upper gastrointestinal endoscopy. Hypoxemia is defined as SpO₂ \<90% lasting ≥10 seconds. Associated respiratory events and potential risk factors will be analyzed without altering routine clinical practice.

Medical Device Clinical Trial Without CE Marking to Evidence Safety and Performance of the INBENTUS VERSATILE Ventilator in Patients Requiring Assisted/Controlled Mechanical Ventilation and Weaning.

Pre-market clinical trial on 81 aldults participants to evidence safety and performance of the non-CE-marked medical device INBENTUS VERSATILE ventilator. The 81 aldult participants are ventilated between 3 and 48 hours with invasive mechanical ventilation (IMV) in assisted/controlled mode and weaning under partial pressure support or volume support, followed by monitoring period until ICU discharge, hospital discharge or 30 days. The study design differentiates between a Validation Cohort (up to 20 participants) for device validation and a Study Cohort (up to 61 participants) for safety and performance confirmation. Serious Adverse Events related to study device and/or its procedure is defined as the primary safety endpoint, whereas technical failure rate is defined as the primary performance endpoint.

Steroid Treatment for Severe Acute Respiratory Infection (STAR) Trial

Multicenter, parallel-group, randomized clinical trial comparing the administration of systemic corticosteroids at a dose equivalent to 40 mg of prednisolone per day for 7 days vs no corticosteroid administration among adults hospitalized with severe acute respiratory infection and hypoxemia.

Skin Pigment/Pulse Oximeter in Congenital Heart Disease (CHD)

Recent retrospective studies have demonstrated differences between pulse oximeter values (SpO2) and measured arterial oxygen saturation (SaO2) in patients identifying as Black or Hispanic. These retrospective studies have limitations because self-reported race is likely not an accurate metric for level of skin pigmentation and the retrospective nature of these studies may impact the accuracy of simultaneous measures of arterial oxygen saturation and pulse oximeter values. The few prospective studies that have evaluated this issue have utilized color-matching techniques to quantify skin pigmentation, and fewer studies have directly measured skin pigmentation in relation it to pulse oximeter accuracy. The aim of this study is to prospectively measure pulse oximeter accuracy in relation to measured levels of skin pigmentation in the congenital heart disease population.

Efficacy of PIMUN by Reducing Intermittent Hypoxia Events

The goal of this clinical trial is to learn if the use of PIMUN(medical device) works to reduce the intermittent hypoxemia of 24-34 weeks of birth gestational age babies. . It will also learn about the safety of the use of PIMUN. The main questions it aims to answer are: Does PIMUN lower the time of oxygen saturation under 90%? What medical problems do participants have using PIMUN? Researchers will compare the use of PIMUN during 48 hours to 48 hours of usual treatments (not using PIMUN). Participants will: Use/ or not use of PIMUN for a 48 hours period- randomly assigned. Regional brain oxygenation by near infrared spectroscopy (NIRS) monitoring at the first day of each 48 hours period. 4-6 hours of polysomnography at the second day of each intervention. Plasma and urine stress oxygen metabolites at the end of each 48-hours intervention.