Action of Carbon Dioxide and Adrenalin on the Heart. 377 

 Table II. — continued. 



B.P. 



I.V.C. 



v.s. 



Kate 

 10 sees 



Output 

 10 sees. 



Output beat . 



Calculated. 



Observed. 



Experiment 4 (10.2.14); 



88 



60 



86 



80 



86 



120 



86 



60 



86 



60 



- 5 c.c. adr 



enalin. 



86 



90 



94 



130 



104 



150 



106 



180 



"5 c.c. adr enalin. 



106 



60 



102 



230 



(1') 108 

 (2') 106 



180 



190 



+ 

 full 



■Dog 4'65 kgrin., heart 52 grm. ; cardiometer on 

 ventricles. 36° C. 



- 8 per cent. C0 2 . 





c.c. 



c". 



c.c. 



20 -5 



109 



4 L 



4-0 



25 



103 



4-1 



4-0 



24 



100 



4 2 



4 o 



26 



111 



4 25 



5 5 



26 



108 -5 



4-15 



4 u 



32 -5 



102 



3 15 



4 -0 



34 



223 



6-5 



6 5 



34 



333 



9-8 



8-75 



34 



333 



9-8 



8 75 



33 



333 



10 -i 



8 -5 



26 -5 



313 



11 8 



10-0 



32 



333 



10-2 



11 -5 



35 



313 



8-9 



6-5 



Experiment 5 (29.1.14). 



106 

 "5 c.c. adr 

 110 

 106 

 108 

 104 



• 8 per cent. COo. 



-Dog 6 - 45 kgrm., heart 44 grm. ; cardiometer on 

 ventricles. 36 '3° C. 



8 per cent. CO., 



190 





23 



190 



7-6 



7 -0 



enalin. 













40 





35 







5-0 



30 





35 o 



189 



5 -3 



6 



40 





34 5 



200 



5 -8 



7-25 



40 





3S 







6-0 



damming back through the failure of the ventricle to pass on the blood which 

 it receives in diastole. 



C0 3 causes a rise of venous pressure, which is proportional to the increase 

 of percentage of CO2, and which is an expression of the slower rate of 

 inflow into the heart, and of the greater damming buck due to the slowed 

 relaxation. With large percentages of COo, the third factor also comes in 

 as an expression of the heart failing to pass on the venous blood it receives. 



The addition ol adrenalin to a heart in good condition lowers the venous 

 pressures (fig. 1). Both the contractile process and relaxation are more 

 rapid, the heart is relatively longer in a relaxed condition and offers less 

 resistance to the inflowing blood ; the heart also passes on the blood better, 

 and the side pressure of the faster venous inflow falls. In good hearts 

 adrenalin is able to diminish, or even counteract, the effect of the C0 2 when 

 the two are employed together. 



