138 MEDULLA 



absorption from the blood stream is relatively slow compared 

 to the rapid distribution of the epinephrine by way of the lym- 

 phatics when injected into the myocardium. The intracardiac 

 injection is best made through a fine needle, 8 cms. long, which 

 is inserted above the fifth rib in the fourth, left, intercostal 

 space. To avoid injury to the internal mammary artery, the 

 injection should be made at a point about a finger's breath from 

 the left sternal margin. 328 



Hyman 320 reports that of 250 intracardial injections in mori- 

 bund individuals, 25 per cent were followed by successful stimu- 

 lation of the heart. Successful results have been reported in 

 cases where the heart had stopped for over ten minutes. 328 



FATE OF EPINEPHRINE AFTER ITS ADMINISTRATION 



The fate of epinephrine in the body is still unknown. It is 

 not excreted in the urine but after large oral doses, catechol 

 derivatives of epinephrine have been detected. The destruc- 

 tion of epinephrine does not occur in the blood stream for the 

 blood has a protective action against the oxidation of epi- 

 nephrine as do also the tissues in general. Nor do the lungs, 

 capillaries, or arterial walls play a part in the destruction. It 

 is most likely that the liver is the chief agent for the removal 

 and destruction of epinephrine. An injection into the portal 

 vein or absorption from the stomach gives only minimal effects 

 since the epinephrine under these conditions reaches the liver 

 before entering the general circulation. On the other hand, 

 in animals with an Eck fistula, epinephrine has a very pro- 

 longed action. 



