Clinical Research Directory

Effect of Acute Hypoxia on RIght VEntRicular Function in Asthma.

More and more people are engaging in sports in the mountains, including individuals with heart or lung diseases. At the same time, such diseases are becoming more common in Switzerland. At high altitude, less oxygen is available, which places stress on the body-particularly on the heart, which has to pump blood through the lungs. How the heart, especially the right ventricle, in people with asthma responds to this stress is still not well understood. Therefore, this study investigates how the heart responds to simulated altitudes of 2,500 m and 4,000 m, both at rest and during light physical activity in patients with asthma. The primary objective is to assess how right ventricular function changes under conditions of reduced oxygen availability. In addition, vital signs, changes in blood gases, oxygen levels in blood and tissue and shortness of breath are assessed. The "altitude" is simulated using a special gas mixture that participants inhale. Participants undergo three altitude conditions (490, 2,500, and 4,000 m above sea level). The order of the altitude conditions is assigned at random. The aim is to better understand how the right ventricle and other parameters respond to low-oxygen conditions and how affected patients can be better supported in the future.

Effect of Hot Spring Therapy on Cognitive Function Recovery During Altitude Training

This randomized controlled trial aims to investigate the effects of hot spring bath therapy on cognitive function recovery, cerebral hemodynamics, and athletic performance in athletes undergoing altitude training. Participants will be randomly assigned to either a hot spring intervention group, a hot water control group, or a blank control group. The hot spring intervention group receives hot spring baths (38°C, 20 minutes) combined with altitude training; the hot water control group receives hot water baths (38°C, 20 minutes) combined with altitude training; and the blank control group receives standard recovery procedures combined with altitude training. Primary outcome measures include cognitive performance assessments (Stroop test, psychomotor vigilance test) and cerebral hemodynamic indicators (functional near-infrared spectroscopy, transcranial Doppler ultrasound). Secondary outcomes included exercise capacity (maximal oxygen uptake, triathlon performance, 500-meter test), blood lactate, and hematological parameters (white blood cells, neutrophils, platelets). These findings may provide evidence for non-pharmacological interventions to enhance cognitive recovery and brain adaptation during altitude training.

OM2 Abbreviated Sensor Verification

The verification of an investigational pulse oximetry board to verify pulse rate and saturation accuracy over a specified saturation range in diverse populations.

Outpatient Pediatric Pulse Oximeters in Africa

The primary objective of this clinical trial is to evaluate the performance of three pulse oximeters during outpatient care within Cape Town, South Africa. This objective will be achieved through generating evidence on how, why, for whom, to what extent and at what cost can paediatric pulse oximetry devices improve the management of hypoxemic children. This will be done with two inter-linked studies: * Aim 1: Determine the impact of two novel paediatric pulse oximeter devices on the correct management of hypoxaemia. * Aim 2: Describe the burden of hypoxaemia and risks for mortality amongst children presenting with acute respiratory infections in a low-resource setting in Cape Town.

OM2 Motion Verification Study

The verification of an investigational pulse oximetry board to verify pulse rate and saturation accuracy over a specified saturation range in diverse populations.

Virtual Reality-Based Simulation Versus High-Fidelity Simulation for Emergency Management Training in Medical Interns

This study is a two-arm parallel randomized controlled non-inferiority trial designed to compare the educational effectiveness of virtual reality (VR)-based simulation with high-fidelity simulation (HFS) for emergency management training in medical interns. Participants will be randomized 1:1 to either VR-based training or HFS-based training for managing desaturation and anaphylaxis scenarios. After training and structured debriefing, all participants will undergo objective structured clinical examinations (OSCEs) and complete pre- and post-training surveys. The primary outcome is OSCE performance score. Secondary outcomes include confidence improvement, participant satisfaction, usability (UEQ-S).

Study of the Effects of Acute Exposure to Moderate Altitude Hypoxia on Prospective Memory.

The goal of this study is to investigate whether prospective memory, i.e., memory for delayed intentions, is impaired at moderate altitude (4,000m). It will also allow to study the effect of air and oxygen administration during hypoxia exposure. The main questions it aims to answer are: * Does moderate acute hypoxia impair prospective memory ? * If so, does air or oxygen adminsitration induce a restoration of prospective memory? Researchers will compare cognitive performance during normobaric hypoxia exposure to cognitive performance during normoxia (control situation). Participants will: * Session S0. Perform a battery of neuropsychological tests and questionnaires). EEG will be recorded during tests. A cheek swab will be performed. * Sessions S1 and S2. Perform several cognitive tasks while exposed to hypoxia and to normoxia (2 different sessions, randomized order) in a normobaric chamber. These are standardized cognitive tests administered on a computer and cognitive tests embedded in a flight simulator scenario. Various questionnaires will be performed on a regular basis. Several physiological measurements will be performed continuously: EEG, ECG, SpO2 and breathing rate. Blood pressure will be measured at the beginning and at the end of hypoxia/normoxia exposure. A blood sample will also be performed. At last, participants will inhale air or oxygen through a mask while making a cognitive task in the chamber.

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.

Effect of Hypoxic Conditioning on Cerebrovascular Health in the Elderly

In line with the ever-growing aging of Western populations, the development of preventive strategies to slow down the effects of aging on cardiovascular health represents a major challenge in order to preserve functional capacities and a sufficient quality of life in the elderly. The alteration of vascular function (at the cerebral and systemic level) with aging is an important feature in the clinical picture including a decrease in physical and cognitive capacities. Although physical activity is recognized as an essential means of combating the effects of aging, optimizing its effects by defining the most effective strategies of practice remains a key objective. Offering alternative interventions to exercise training is also necessary for people who are unwilling or unable to engage in a physical activity program. In this context, hypoxic conditioning, alone or in conjunction with rehabilitative exercise training, is a new therapeutic modality with strong preclinical validity, in particular from a cardiovascular standpoint, and used in other pathologies to improve cardiovascular function and exercise performance and quality of life. Our aim is, therefore, to investigate the effect of hypoxic conditioning (alone or in conjunction with exercise training) on cerebrovascular health in the elderly.

Structural Modification In Supraglottic Airway Device

The proposed A/Z modification of a supraglottic airway (SGA) incorporates an opening in the SGA body that enables access to the endotracheal tube (ETT) through the body of the SGA without the need of using an exchange catheter, thus enabling an ETT to move in the body of the SGA and convert a supraglottic to endotracheal ventilation. In its original form an adaptor made from same material currently used in the endotracheal tubes can make ventilation through the proposed airway device possible in exactly the same manner of a conventional SGA currently used. This adapter also known as the R-piece can be replaced with an ETT. The modification also allows placement of SGA over an existing ETT to convert and endotracheal (ET) to supraglottic (SG) mode of ventilation without the need to use an exchange catheter.

Nocturnal Hypoxia in Geriatric Patients After Hip Fracture

Delirium is a common complication following hip fracture surgery (HFS) in older people. Postoperative hypoxia has also been associated with delirium, but not specifically in geriatric patients. The aim of the study is to demonstrate that post-operative hypoxia is associated with in-hospital complications in patients with HFS.

High-Flow Nasal Cannula for Preventing Hypoxia During Sedated Endoscopy in High-Risk Obstructive Sleep Apnea Patients

Hypoxia represents the most frequent adverse event during propofol-sedated gastrointestinal endoscopy. The STOP-BANG questionnaire serves as a widely adopted, straightforward tool for screening obstructive sleep apnea (OSA) risk, with a score ≥5 identifying high-risk OSA patients who are particularly susceptible to hypoxia under sedation. Although preliminary research from our team suggests that High-Flow Nasal Cannula (HFNC) may lower the incidence of hypoxemia, evidence remains limited and inconsistent in studies specifically targeting high-risk OSA populations. Therefore, this multicenter randomized controlled trial aims to evaluate whether HFNC can effectively reduce the occurrence of hypoxia during sedated gastrointestinal endoscopy in patients identified as high-risk for OSA.

Effect of Acute Hypoxia on RIght VEntRicular Function in HAPE.

More and more people are engaging in sports in the mountains, including individuals with heart or lung diseases. At the same time, such diseases are becoming more common in Switzerland. At high altitude, less oxygen is available, which places stress on the body-particularly on the heart, which has to pump blood through the lungs. How the heart, especially the right ventricle, in people with past HAPE responds to this stress is still not well understood. Therefore, this study investigates how the heart responds to simulated altitudes of 2,500 m and 4,000 m, both at rest and during light physical activity in patients with past HAPE. The primary objective is to assess how right ventricular function changes under conditions of reduced oxygen availability. In addition, vital signs, changes in blood gases, oxygen levels in blood and tissue and shortness of breath are assessed. The "altitude" is simulated using a special gas mixture that participants inhale. Participants undergo three altitude conditions (490, 2,500, and 4,000 m above sea level). The order of the altitude conditions is assigned at random. The aim is to better understand how the right ventricle and other parameters respond to low-oxygen conditions and how affected patients can be better supported in the future.

Impact of Iron Supplementation on Right Ventricular Function and Exercise Performance in Hypoxia

The purpose of this study is to determine if taking iron supplement pills improves exercise performance in low-oxygen conditions.

Comparison of the Oxymask and Oxy2mask on Supplemental Oxygen Delivery

The purpose of this study is to determine if the performance of a newly released oxygen mask is the same, better, or worse than previous mask version. We will measure the flow rate necessary to maintain the same oxygen saturation in adult patients using each mask.

Hypoxia and Hemodilution Testing in Healthy Adult Volunteers

This study will collect physiological measurements in healthy adult volunteers under controlled hypoxia and hemodilution conditions.

Adaptation of Lung Transplant Recipients at Extreme Altitude

This prospective observational study investigates the effects of intermittent hypoxic conditioning and real high-altitude exposure in lung transplant recipients compared with healthy controls. The study includes an eight-week home-based preparatory phase during which participants use a normobaric hypoxic tent with reduced oxygen concentration. Prior to this phase, all participants receive standardized training on the safe use of the equipment. During the preparatory period, daily vital parameters, including heart rate, oxygen saturation, and heart rate variability, are recorded using a sports watch and a pulse oximeter. Symptoms, adverse events, and subjective well-being are documented daily in an electronic diary. All data are transmitted to the study team via encrypted electronic systems, allowing continuous remote monitoring. At the end of the preparatory phase, participants undergo a clinical evaluation to confirm fitness for the expedition phase. The expedition phase consists of a monitored ascent of Aconcagua (6,971 meters). Before departure, all participants are required to attend a comprehensive safety, protection, and first aid training conducted jointly by the study team and professional expedition providers. The expedition is planned and led by an experienced international expedition company in cooperation with a local provider specializing in high-altitude mountaineering. The expedition includes arrival in Mendoza, preparatory procedures such as equipment checks and permits, followed by a staged ascent to base camp. Subsequent days involve rest periods and acclimatization hikes with the establishment of progressively higher camps. A summit attempt is planned after sufficient acclimatization, followed by descent to high camp. A weather-dependent buffer period is included before the final descent to the valley and return to Mendoza, where the expedition concludes. Total study participation is expected to last approximately 15 weeks, including about eight weeks of home-based preparation and approximately three weeks at altitude. A final follow-up examination is conducted 2 to 4 weeks after completion of the expedition, marking the end of study participation.

Effect of Acute Hypoxia on RIght VEntRicular Function in Healthy Adults.

More and more people are engaging in sports in the mountains, including individuals with heart or lung diseases. At the same time, such diseases are becoming more common in Switzerland. At high altitude, less oxygen is available, which places stress on the body-particularly on the heart, which has to pump blood through the lungs. How the healthy heart, especially the right ventricle, responds to this stress is still not well understood. Therefore, this study investigates how the heart responds to simulated altitudes of 2,500 m and 4,000 m, both at rest and during light physical activity. The present investigation focuses on healthy individuals in order to establish a reference for future comparisons with patients suffering from cardiopulmonary diseases. The primary objective is to assess how right ventricular function changes under conditions of reduced oxygen availability. In addition, vital signs, changes in blood gases, oxygen levels in blood and tissue and shortness of breath are assessed. The "altitude" is simulated using a special gas mixture that participants inhale. Healthy participants undergo three altitude conditions (490, 2,500, and 4,000 m above sea level). The order of the altitude conditions is assigned at random. The aim is to better understand how the right ventricle and other parameters respond to low-oxygen conditions and how affected patients can be better supported in the future.

Pulse Oximeter Accuracy During Stable Hypoxia Plateaus

The aim of this study is to determine the accuracy of devices called pulse oximeters, which measure blood oxygen by shining light through fingers, ears or other skin, without requiring blood sampling. Study will be used with healthy volunteers at rest.

Pharmacologic Induction of Tolerance for Hypoxia & Hypothermia

Warfighter Performance Optimization in Extreme Environments remains an area of important and intense investigation, with the following goals: (1) Optimize, sustain and augment medical readiness and physiological/ psychological performance in extreme and hazardous military operational environments and (2) develop joint DoD countermeasures and guidance to sustain performance, assess physiological status, and reduce injury risk in extreme and hazardous operational environments. Successful and safe outcomes in extreme and hazardous operational environments require that warfighters maintain optimum cognitive and exercise performance during physiologic stress. Extreme environmental conditions encountered in such environments include warfighter exposure to hypoxia and hypothermia, alone or in combination. Both hypoxia and hypothermia undermine O2 delivery system homeostasis, imposing dangerous constraints upon warfighter cognitive and exercise capacity. While red blood cells (RBCs) are commonly recognized as O2 transport agents, their function as a key signaling and control node in O2 system delivery homeostasis is newly appreciated. Through O2 content-responsive modulation of RBC energetics, biomechanics, O2 affinity and control of vasoactive effectors in plasma - RBCs coordinate stabilizing responses of the lung, heart, vascular tree and autonomic nervous system - in a fashion that maintains O2 delivery system homeostasis in the setting of either reduced O2 availability (hypobaric hypoxia) or increased O2 demand (hypothermia). Human RBCs demonstrate adaptive responses to exercise, hypoxia and hypothermia - these changes are commonly appreciated as a key element enabling high altitude adaptation. However, under conditions of hypoxia and hypothermia, without prior adaptation, RBC performance is adversely impacted and limits the dynamic range of stress adaptation for O2 delivery homeostasis - therefore limiting warfighter exercise capacity and cognitive performance in extreme environments, such as during acute mountain sickness.

The Efficacy and Safety of the Supraglottic Oxygenation Via Nasotracheal Intubation for Deep Sedation Fiberoptic Bronchoscopy

Bronchoscopy is now widely used for the diagnosis and treatment of various respiratory diseases. However, the procedure is highly stimulating and provokes a strong stress response; because the airway is shared, patients are prone to hypoxia. With the growing emphasis on comfortable care, demand for anesthesia during bronchoscopy has increased. Deep sedation is the most common approach, but when administered in the supine position it often causes the tongue base to fall back. Both nasopharyngeal and oropharyngeal airways can relieve this obstruction, yet neither connects seamlessly to an oxygen supply line, resulting in insufficient oxygen delivery.We therefore replaced the nasopharyngeal airway with a wired endotracheal tube (size 4.0 or 4.5) inserted via the nose. This thinner tube couples easily to an oxygen line or ventilator circuit, partially relieves airway obstruction, and allows ample supraglottic oxygenation. The present study was designed to evaluate the feasibility and safety of this modified oxygen-delivery method in patients undergoing deep sedation for bronchoscopy.

Hypoxia and Heart Rate Variability

The purpose of this study is to evaluate how variations in oxygen demands may change heart electrical activity in individuals with and without oxygen dependence.

Graded Exercise Hypoxia Testing

The purpose of this study is to develop a single, standardized test to determine how individuals tolerate acute hypoxia in a stepwise fashion. We aim to evaluate the association between multiple factors, such as ventilatory compensation, heart rate response, acid-base changes, sex, pulmonary function, etc, which may explain why some individuals tolerate exercise in hypoxia better than others. Identifying these factors of association will inform future pharmacological and non-pharmacological attempts to combat acute hypoxic exercise.

The Efficacy of Remimazolam on Incidence of Hypoxia During Sedated Transvaginal Oocyte Retrieval: A Multicenter Randomized Controlled Trial.

Hypoxia is the most common adverse reaction during sedation outside the operating room.Exploring novel drug combinations to reduce the incidence of hypoxia during sedation in patients undergoing transvaginal oocyte retrieval procedures enhances patient safety and lowers perioperative adverse event rates. This multicenter, prospective, randomized, controlled clinical study will compare the hypoxia incidence rate of the remimazolam-alfentanil combination against the commonly used propofol-alfentanil combination.