A simple "new" method to accelerate clearance of carbon monoxide

The currently recommended prehospital treatment for carbon monoxide (CO) po isoning is administration of 100% O-2. We have shown in dogs that normocapn ic hyperpnea with O-2 further accelerates CO elimination. The purpose of th is study was to examine the relation between minute ventilation ((V) over d ot E) and the rate of elimination of CO in humans. Seven healthy male volun teers were exposed to CO (400 to 1,000 ppm) in air until their carboxyhemog lobin (COHb) levels reached 10 to 12%. They then breathed either 100% O-2 a t resting (V) over dot E (4.3 to 9.0 L min) for 60 min or O-2 containing 4. 5 to 4.8% CO2 (to maintain normocapnia) at two to six times resting (V) ove r dot E for 90 min. The half-time of the decrease in COHb fell from 78 +/- 24 min (mean +/- SD) during resting (V) over dot E with 100% Oz to 31 +/- 6 min (p 0.001) during normocapnic hyperpnea with O-2 The relation between ( V) over dot E and the half-time of COHb reduction approximated a rectangula r hyperbola. Because both the method and circuit are simple, this approach may enhance the first-aid treatment of CO poisoning.