HYPER MIND - Hyperoxia Effects on Cerebral Hemodynamics (NCT07377162) | Clinical Trial Compass
RecruitingNot Applicable
HYPER MIND - Hyperoxia Effects on Cerebral Hemodynamics
Belgium80 participantsStarted 2024-01-01
Plain-language summary
This study aims to better understand how short periods of exposure to high oxygen levels affect blood flow in the brain of patients who are intubated and mechanically ventilated in the Intensive Care Unit (ICU). Many ICU patients receive more oxygen than strictly necessary, and high blood oxygen levels (hyperoxemia) are very common. However, the immediate effects of short hyperoxic exposures on cerebral circulation and autoregulation remain poorly understood.
In this study, patients who already require mechanical ventilation for medical reasons will undergo a brief and controlled increase in the oxygen delivered through the ventilator (FiO₂). During this time, we will continuously monitor blood flow in one of the main brain arteries using a non-invasive ultrasound technique called transcranial Doppler (TCD). The goal is to evaluate how cerebral blood flow, pulsatility, and autoregulatory capacity change during and after a short hyperoxic stimulus.
No additional invasive procedures are required beyond standard ICU monitoring, except for the temporary adjustment of the ventilator's oxygen settings and arterial blood gas sampling, which are part of usual care in critically ill patients. Participation does not provide direct clinical benefit but may help improve future oxygen management in ICU patients. The study involves minimal risk, as short hyperoxic exposures are already common in routine care and will be interrupted immediately in case of any adverse event.
Who can participate
Age range
18 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria
* Adult patients aged ≥18 years
* Admitted to the intensive care unit (ICU)
* Intubated and mechanically ventilated for ≤72 hours
* Receiving volume-controlled mechanical ventilation
* Arterial partial pressure of carbon dioxide (PaCO₂) between 35 and 45 mmHg
* Invasive arterial blood pressure monitoring in place
* Adequate transcranial Doppler (TCD) acoustic window
* Clinically judged to be suitable for a brief normobaric hyperoxic stimulus
* Expected to receive one or two hyperoxic steps based on baseline FiO₂ requirements: a) Baseline FiO₂ \< 0.5: two-step hyperoxic stimulus (FiO₂ 0.5 followed by FiO₂ 1.0); b) Baseline FiO₂ ≥ 0.5: one-step hyperoxic stimulus (FiO₂ 1.0)
Exclusion Criteria:
* Age \<18 years
* Pregnancy
* Extracorporeal membrane oxygenation (ECMO)
* Continuous renal replacement therapy (CRRT)
* Contraindications to hyperoxia, as judged by the treating physician
* Severe hemodynamic instability requiring changes in vasopressor dose during the recording period
* Inability to obtain a reliable transcranial Doppler signal through the temporal acoustic windows
* Any clinical condition deemed by the treating physician to pose unacceptable risk during hyperoxic exposure
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Change in Mean Flow Index (Mx) During Normobaric Hyperoxia
Timeframe: Baseline (prior to hyperoxic exposure), during normobaric hyperoxia steps, assessed during the intervention period, and after returning to baseline (assessed up to 20 minutes)