Oxygen Reduction and Reaction Time in Hypoxic and Normal Drivers

Abstract

Thirty young, healthy, nonsmoking drivers and 30 older, presumably hypoxic, nonsmoking drivers were exposed to an average of 38.1 ppm of carbon monoxide (CO) during 90 minutes of commuting traffic. These groups showed an average of 0.49 and 1.14 vol% reduction in oxygen (O₂) of capillary blood, respectively. A control group of 30 averaged a 0.04 vol% reduction. Correlation of CO exposure with O₂ reduction was highly significant. In both groups, 27 of the 30 drivers were slower in reaction time to a visual stimulus after being in traffic. The control group was 3.5% faster in reaction time the second time. Correlation of O₂ reduction and time slowing was significant. The hypoxic drivers had significantly less O₂ and were significantly slower in reaction time at the beginning than were the normal drivers.