PERFUSIOX OF THE HEART 



427 



strong and vigorous. Then take a normal record. Keturn 

 the fluid which has already passed through the heart to the 

 stock solution and prepare to inject some adrenaline with 

 the hypodermic syringe through the wall of the rubber tube 

 just above the heart. Two cubic centimeters of 1:10,000 

 solution may be injected slowly and steadily. How does 

 this affect the record! How long does the action on the 

 heart last? Do not return the solution into wliicli any dnif/ 



.Vessels s, fat in left or ventral 



lonqitudmal groove 



Riqht ventricle 



Left ventricle 

 Left auricle 



Posterior 

 vend cava 



Conus arteriosus 

 Pulmonary Artery 



Right auricle 

 Anterior vena cava 



Brachio- 

 cephalic Art. 



Left Brachial Artery 



Pulmonary Veins 



Left Pulmonary Artery 



Aorta 



Lie/amentum arteriosum i 



Fig. 342. Dog's heart. 



has passed to the stock solution. Change beakers to catch 

 the outflow as soon as the drug has all passed out. 



When the heart returns to normal inject some potassium 

 chloride solution (one per cent) and get a record of the re- 

 sult. FolloAv this with a solution of digitoxin (five cubic 

 centimeters equal one milligram). Do not inject too much. 

 How does this affect the heart? When a satisfactory record 

 has been obtained (give more digitoxin if necessary) then 

 inject a second dose of potassium chloride and follow this 



