Effects of Anesthetics on Osmotic Resistance of Erythrocytes: III. Carbon-Dioxide with Oxygen.

A mixture of 25% carbon-dioxide with 75% oxygen was administered to dogs without rebreathing. This greatly increased the amplitude of respiration and induced anesthesia with abolition of the corneal reflex in 6 minutes. The pulse was greatly retarded. The mucous membranes remained pink. Clonic convulsions initiated by tremors came on within 10 minutes after induction, and violent tetanic convulsions quickly followed. Upon administering pure oxygen the convulsions promptly stopped, the pulse became very rapid, and the animals recovered. In all cases, except in the weaker dilutions (0.4%), the resistance of the erythrocytes to hypotonic Simmel's solutions was greater than normal.

After the administration of CO₂, much difficulty was experienced in obtaining blood because of the rapid clotting. Hickman noted this action of carbon-dioxide a century ago. Dr. Cline Chipman of Washington, D. C., has observed clinically that a few breaths of carbon-dioxide administered during the anesthetic period will greatly shorten the coagulation time of blood. This has been confirmed by Dr. R. M. Waters of Madison, Wis., and by Dr. M. E. Botsford and Dr. M. J. Price of San Francisco. Such an effect of carbon-dioxide may be of great clinical value in certain cases of capillary oozing at operation. Some phases of the relation of the CO₂ content of blood to its coagulation time have recently been studied by Baumberger. 1