Hand Perfusion and Pulse Oximetry Performance

"Subjects will be fitted with a mouthpiece and/or facemask to systematically reduce the fraction of inspired oxygen (FiO2) they breathe, starting with room air (21% O2), and then progressive hypoxic mixtures of 18%, 15%, 12%, and 10% FiO2 in sequence for five minutes each.~Blood flow to the hand downstream from the brachial catheter will be increased by brachial artery infusions of adenosine administered at 6.25 mcg/100ml tissue per minute for 30 minutes into the brachial artery to increase blood flow by 5 to 10-fold."

"Subjects will be fitted with a mouthpiece and/or facemask to systematically reduce the fraction of inspired oxygen (FiO2) they breathe, starting with room air (21% O2), and then progressive hypoxic mixtures of 18%, 15%, 12%, and 10% FiO2 in sequence for five minutes each.~Blood flow to the hand downstream from the brachial catheter will be decreased to \~25% of baseline, by infusing norepinephrine at 4 ng/100ml of tissue per minute for 30 minutes."

Subjects will be fitted with a mouthpiece and/or facemask to systematically reduce the fraction of inspired oxygen (FiO2) they breathe, starting with room air (21% O2), and then progressive hypoxic mixtures of 18%, 15%, 12%, and 10% FiO2 in sequence for five minutes each.