56 



Scientific Proceedings (96). 



being or any subsequent serious microscopic lesions in the lung 

 tissue. 



By means of the use of colored solutions, such as India ink, it 

 has been shown that even the last portions of the fluid introduced 

 actually pass throughout the lung tissue and do not simply flow 

 back through the trachea without entering the lung. 



Such irrigation procedure is relatively effective in removing 

 material from the lung. The preliminary insufflation of such 

 materials as India ink, protargol, or starch paste, followed by 

 irrigation with salt solution has shown that a large percentage of 

 the indicator was removed by the perfusion. In the same way 

 an irrigation of the lungs with 3,000 c.c. of salt solution following 

 an insufflation of a heavy broth culture of B. prodigiosus removed 

 90 per cent, of the number of organisms introduced. 



As a corollary to the above experiments a study was made of 

 absorption from the lung. A series of dogs was given by insuffla- 

 tion 20 c.c. of salt solution per kilogram of body weight, and at 

 stated intervals the dogs were killed and the lungs were examined 

 grossly and histologically. The appearance of the lungs imme- 

 diately after the insufflation showed them to be filled with fluid. 

 Within 48 hours much of the fluid has been absorbed and after 

 four days the lungs are practically free of fluid. Histologically, 

 the lesions were inconspicuous, giving evidence of but little in- 

 flammatory reaction. 



The rapidity of absorption was further confirmed by com- 

 parative determinations in the same animal of the excretion of 

 phenolsulphonephthalein when administered by intramuscular 

 and intravenous injections, and by intratracheal insufflation. 

 The percentage excretion within two hours after the several modes 

 of administration were: 



Intravenous injection. . . . 

 Intramuscular injection. . 

 Intratracheal insufflation 



78.1 

 72.5 

 57-i 



