Accuracy of Pulse Oximeters During Profound Hypoxia (APO)
Hypoxia
About this trial
This is an interventional screening trial for Hypoxia focused on measuring SpO2, photoplethysmography, camera based photoplethysmography
Eligibility Criteria
Inclusion Criteria: • Healthy subjects (ASA 1 and ASA 2) between 18 and 65 years of age upon signing the informed consent. (ASA: American Society of Anesthesiologist's health score). In each group, at least 30% of one gender need to be present, and at least 15% of participants have a Fitzpatrick's skin color scale of 5 or 6. Exclusion Criteria: Heavy smokers or individuals exposed to high levels of carbon monoxide that result in elevated carboxyhemoglobin levels. Individuals subject to conditions that result in elevated levels of methemoglobin. Individuals with low SpO2 or SaO2 (<95%) at FiO2 = 0,21 Moderate to severe claustrophobia for small rooms Severe obesity (BMI > 35 kg/m2) Hemoglobinopathies Arteriopathies, including Raynaud disease ASA 3 to 5 subjects Tattoo's, skin lesions,use of skin lotions or use of nail polish/fake nails at the region of interest for TDw and TDc Pregnancy
Sites / Locations
- Hypoxia Centre of the Complementary Medical Centre (CMC)Recruiting
Arms of the Study
Arm 1
Arm 2
Arm 3
Arm 4
Experimental
Experimental
Experimental
Experimental
NI(Fast-Sitting)
NI(Slow-Sitting)
NI(Fast-Lying)
IN(Fast-Sitting)
Subgroup Non-Invasive (Fast-Sitting): sitting volunteers undergo an ambient oxygen decrease from 21% to 10% (SpO2 <73% for 1 minute) followed by a fast increase of ambient oxygen concentration. Fast: if the study is completed for a volunteer reaching SpO2 ≤73%, the subject leaves the room and breaths 21% oxygen. The hypoxia inducing device is stopped after all subjects left the hypoxia room and the door of the hypoxia room is opened, allowing air with 21% O2 to enter the room. Airco fan stays running.
Volunteers of subgroup Non-Invasive (Slow-Sitting) follow the NI (Rapid-Sitting) protocol, but after hypoxia at FiO2=0,10 oxygen normalization is programmed to increase at the same speed as the hypoxia creation. Slow: after target hypoxia has been reached, air with 21% of oxygen is allowed to enter the room in such a way that the speed of increase of O2 to 21% is approximately equal to the decrease of the room's oxygen to 10%
Volunteers included in the Non-Invasive (Fast-Lying) group follow the NI (Rapid-sitting) protocol although in lying position.
After full completion of the Non-Invasive (NI) studies, and a defined algorithm to compute SpO2 by TDw1 is achieved, the study is repeated as described for the NI (Rapid-Sitting) protocol, but arterial blood oxygen saturation (SaO2) will be determined during 5 stable ambient oxygen plateaus (the Invasive (Fast-Sitting) study). These results are used as benchmark to define the final accuracy of TDw1 for SpO2 reproduction. In this part of the study, according to the minimal requirements of the regulatory agencies, 12 volunteers that successfully completed the study will be included.