TerminatedNot Applicable

Flow Rate Impact on Arterial Carbon Dioxide During THRIVE

Stopped: Futility. Inclusion and logistics of study in a clinical situation proved too difficult to continue.

Sweden1 participantsStarted 2022-02-08

Plain-language summary

Apneic oxygenation describes the process of continuous oxygenation of the blood without breathing efforts. This anesthesia technique has been described in the literature for more than 100 years and is sometimes used under general anesthesia, e.g. during surgery of the vocal chords. Although this technique usually provides marked prolongation of the apneic period because of excellent oxygenation, it is limited by the absence of ventilation and the corresponding accumulation of carbon dioxide in the blood. This will lead to worsening respiratory acidosis and associated complications, such as cardiac arrythmias. In 2015 it was reported that apneic oxygenation with high-flow nasal oxygen delivery systems (HFNO), a device that provides heated humidified oxygen at high flow rates (usually 30-70 L/min), resulted in less carbon dioxide accumulation compared with historical controls. This specific technique of apneic oxygenation was termed transnasal humidified rapid-insufflation ventilation exchange (THRIVE). To date, the impact on different flow rates on blood carbon dioxide accumulation during THRIVE is unknown. Specifically, very high flow rates, exceeding 70 L/min have not been investigated. Therefore, the aim of this trial is therefore to study the rate of accumulation of carbon dioxide during THRIVE at two different flow rates: 40 and 100 L/min.

Who can participate

Age range

18 Years – 65 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: * Patients presenting for elective surgery Exclusion Criteria: * Age \<18 or \>65 years * Body Mass Index (BMI) \>35 kg m-2 * American Society of Anesthesiology classification \> 2 * Physical activity level less than 5 metabolic equivalents * Obstruction of the upper airways * Known or high clinical suspicion of difficult airway * Obstructive sleep apnea syndrome * Increased risk of aspiration * Pulmonary or cardiac condition resulting in a reduction of physical activity level equivalent to the New York Heart Association class of 2 or higher. * Any contraindication to high-flow nasal oxygen therapy or hypercapnia * Pregnancy or breastfeeding * Allergy to any of the anesthetic agents used in the study * Inability to comprehend oral or written information.

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

Arterial partial pressure of carbon dioxide (PaCO2) accumulation rate

Timeframe: 10 minutes

Trial details

NCT IDNCT05234424

SponsorUppsala University Hospital

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2024-05-13

View on ClinicalTrials.gov More Apneic Oxygenation trials