Effects of 1, 1, 1-Trichloroethance Inhalation on Respiration and Blood Gas Tension

Changes in respiration and arterial blood gas tension following 1, 1, 1 -trichloroethane (1, 1, 1 -TCE) inhalation were investigated in anesthetized dogs. In acute in halation experiments, both increase in respiratory rate and a decrease in amplitude of respiration were observed following inhalation of higher 1, 1, 1 -TCE concentrations. The threshold concentration of 1, 1, 1 -TCE required to produce a increase in respiratory rate was approximately 0.7 to 0.9% in inspired air, and dose response relationship between the increase in respiratory rate and 1, 1, 1 -TCE concentrations which exceeded the threshold level was observed. Moreover, a trancient increase in arterial oxygen tension, a decrease in carbon dioxide tension and an increase in pH were observed following inhalation of higher 1, 1, 1 -TCE concentrations in spontaneous breathing. However, oxygen tension, carbon dioxide tension and pH remained unchanged following inhalation in artificial breathing. It is suggested that alterations of blood gas tension and pH may be based on mainly the increase in respiratory rate resulting from 1, 1, 1 -TCE inhalation in anesthetized dogs.