26 



Scientific Proceedings (51). 



18 (714) 



The development of experimental pneumonia under direct obser- 

 vation of the lungs in the living animal. 



By Martha Wollstein and S. J. Meltzer. 



[From the Laboratories of the Rockefeller Institute.] 



Experimental pneumonia produced by intra-bronchial insuf- 

 flation of virulent pneumococci may develop quite rapidly. Thus 

 in the experiments of Lamar and Meltzer it was observed that 

 in one instance seven hours after the injection, nearly complete 

 consolidation affecting the greater part of one lobe was already 

 present. We therefore now made several experiments in which 

 the lungs were under direct observation continuously for several 

 hours after the insufflation of the culture. The procedure 

 has been as follows. The dog was anesthetized by the cone 

 method, and a tube introduced into a bronchus as deep as it 

 could be pushed; the pneumococcus culture was then injected. 

 Immediately after, the tube was withdrawn, so that its lower 

 end was just above the bifurcation, and the arrangement made 

 for continuous intratracheal insufflation. The dog received about 

 "half ether" and was continually under complete anesthesia. 

 The thorax was now widely opened transversely and about two 

 thirds of three or four of the lower ribs on the right side removed ; 

 the right lower lobe, which is usually the seat of the inflammation, 

 was now exposed to full view. We shall not enter here upon 

 details. It may suffice to state that we were able to watch the 

 successive stages from the earliest signs of engorgement to complete 

 hepatization. We were also able to establish changes in the ausculta- 

 tion phenomena in the consolidated parts, in some instances even 

 clearly suggesting tubular breathing. We intended to demonstrate 

 such experiments, and we prepared several animals for this purpose. 

 The experiments were successful indeed, but we did not take the 

 lateness of the hour of the meeting sufficiently into account. We 

 prepared the experiments too early and all the animals died before 

 the meeting began. The acute infection, the great loss of heat, 

 the severe operation, and the long-lasting anesthesia are severe 

 factors to contend with. So far five hours has been the longest 



