Technique for accurately producing desired carboxyhemoglobin levels during rest and exercise

A method is described for accurately adjusting a subject's blood carboxyhemoglobin (HbCO) level and then maintaining this level during either rest or exercise. The data presented describe the constancy with which HbCO levels (between 3 and 5% HbCO)were maintained despite varying the inspired ventilatory volumes from 5 to 120 1/min (BTPS). After an initial bolus inhalation of CO to bring the blood HbCO to a desired level, the concentration of CO in the inspired air to maintain this level of HbCO can be predicted from the following equation: COI (ppm) = desired %HbCO divided by 0.180.