368 CO, Capacity of Blood. IV 
under these conditions the CO, content and the CO: capacity of 
the blood were still practically normal, and arterial pressure had 
not suffered any considerable fall. Both the CO, administration 
and the manipulation were then stopped for 2 hours. No very 
marked change followed. Then the manipulation was repeated 
but without inhalation of CO.. In 20 minutes the CO: content 
and capacity had fallen to the critical level and arterial pressure 
was undergoing a decline which ended 25 minutes later in death. 
In Experiment 3 the manipulation of the stomach was car- 
ried out in the manner above described for 1 hour. The animal 
did not breathe CO.. 23 minutes after the termination of this 
treatment death followed. 
Experiment 2.—Dog, female, 9 kilos. Manipulation of stomach. Equi- 
librating air 5.4 per cent COs. 
ernie Blood COz. eS: 
Time. Condition. tions hei 
A ee te Content. | Capacity. 
p.m. vol. per centivol. per cent mm. 
2.00 | Normal. 20 48 49 
3.15 | Morphine, 0.19 gm. 10 
3.30 if 61 54 126 
3.45 | Gastric manipulation 
started. 
4.00 50 43 52 94 
4.15 30 49 
4.30 46 28 38 86 
4.45 | Manipulation stopped. 
Reflexes absent. 
5.00 36 oF 32 58 
5.08 | Dog dead. . 40 
In Experiments 4 and 5 the manipulation of the stomach was 
carried out until a distinct condition of shock as judged by CO, 
capacity, absence of reflexes, and low arterial pressure was at- 
tained. The attempt was then made to reverse these conditions 
and to restore the animal by causing it to inhale CO; in the per- 
centages shown in the protocols. In neither case was there any 
distinct improvement, and death followed. Autopsy showed 
little engorgement of the intestines and no hemorrhage, but there 
was a marked dilatation of the stomach. 
