William B. Draper

Studies on diffusion respiration. VII. The cortical electrical activity of dogs

Abstract 1.1. The behavior of the cortical electrical activity of dogs held in apnea by an overdose of Pentothal sodium for 45 min. under conditions permitting diffusion respiration has been studied. 2.2. The EEG exhibited initial slowing followed by periodic suppressions and finally complete and continuous suppression. Continuous suppression appeared at an average of 19 min. of respiratory arrest and lasted until the apnea was artificially terminated, or for an average of 26 min. 3.3. The CO 2 content of the blood progressively increased throughout the apnea and at the 45th min. of respiratory arrest the average venous blood pH had fallen from a control of 7.29 to the low value of 6.69. 4.4. The EEG of all animals returned to normal within 1 week following the experiment.