A Single-Center, Prospective Study in Healthy Subjects to Validate a New OXYGEN RESERVE INDEX (ORI)

Monitoring a patient*s oxygen status during anesthesia using pulse oximetry is
essential. The new Oxygen Reserve Index (ORI) may help provide clinicians
real-time visibility to oxygenation in a moderate hypoxic range and serve as a
warning of an impending hypoxic state. In this way, ORI may enable proactive
interventions to avoid hypoxia

The primary objective is to validate the new Oxygen Reserve Index (ORI) by
collecting optical data using the Rainbow SET Pulse CO-Oximeter (Masimo Corp.)
and comparing them to whole blood references of arterial and venous blood drawn
in healthy volunteers.

Prospective first in human validation intervention study at one single center

Each subject will undergo the following interventions
• Change in inspiratory oxygen fraction (FiO2):
• Normoxia: room air (FiO2 0.21) (baseline)
• Hyperoxia: 100% oxygen (FiO2 1.0)
• Hypoxia: breathing mixtures of N2 in air via a tight fitting facemask to
reach arterial oxygen saturation levels of just below 90%, 80%, and eventually
70% as measured by pulse oximetry (Radical 7, Masimo Corp.)
• Change in expiratory carbon dioxide concentration (etCO2) (during normoxia,
awake state):
• Normoventilation (etCO2 4.5 - 5 Vol%)
• Partial rebreathing or adding external medical CO2 (target etCO2 7 - 7.5
Vol%)
• Hyperventilation (target etCO2 2.5 - 3 Vol%)
• A vascular occlusion test (VOT) will be performed by inflating an upper arm
blood pressure cuff at each intervention.

Noninvasive measurement risks: The risk from noninvasive pulse oximeter devices
is minimal since the measurement is noninvasive and uses optical technology
similar to conventional pulse oximetry. Sensor risks: As with all optical
sensors, the investigational device has the risk of thermal burn. The design
includes safeguards, and this risk is believed to be low. Pressure damage may
occur to the tissue if the sensor is placed too tightly. Sensors will be
attached with adhesive, and may be secured by a supplemental headband. This
risk is believed to be low. Optical exposure is minimized by procedure and low
power. This risk is believed to be low. Radial artery line placement: Arterial
catheters have been found to be relatively safe with a low incidence of serious
complications. Common complications include temporary radial artery occlusion
and hematoma. Less common complications (less than 1% of procedures) include
localized catheter site infection, hemorrhage, sepsis, permanent ischemic
damage and pseudoaneursm formation. Arterial draws: The most common
complications associated with arterial draws are hematoma and bruising. Oxygen
desaturation protocol: The risks of the brief exposures to hypoxia include
feeling short of breath, headache, and dizziness. Brief loss of consciousness
may occur, but is not expected at the levels of oxygen targeted for these
tests. Benefits: There will be no direct benefits to the enrolled volunteers.
Future benefits to patients might include a reduction in invasive procedures
due to the ability to trend moment-by-moment physiological variables such as
cerebral oximetry