Method for Experimental Production of Chronic Abscess of Lung. ∗

Abstract

In the attempt to produce in an experimental animal an abscess of the lung that is identical with the postoperative pulmonary abscess in man, we considered the factor of chronicity to be of major importance. In the work of Cutler, Holman, Schlueter, Holloway and Weidlein 1 , 2 , 3 , 4 , 6 the abscesses produced by the embolic method were all of the acute type and healed spontaneously within 3 weeks after the embolus containing the bacteria had been set free into the general circulation. Van Allen, Fox and Colle 5 showed the importance of cough in the prolongation of the suppurative processes in the lung. Because spirochetes, fusiform bacilli and other anaerobic organisms of the mouth are so frequently found in the chronic abscesses of the lung in man it was thought advisable to study the behavior of these anaerobic organisms when implanted in the pulmonary tissues by means of an arterial embolus. In previous experiments it was determined that when these organisms were introduced by way of the bronchi chronic pulmonary abscess was not produced.

Method: Series 1. 24 dogs. Material taken from the gum margins of a patient with pyorrhea alveolaris was placed within a segment of vein and the ends of the vein tied with silk suture. The experimental embolus thus produced was forced into the venous circulation through a glass cannula by means of normal saline solution from a syringe. Fresh preparations of the material used in these septic emboli were examined with a dark-field microscope and a large number of spirochetes and various types of fusiforni bacilli and innumerable other motile and non-motile organisms were found. Cultures of this material revealed the presence of both aerobic and anaerobic micro-organisms. In each of the 24 animals an abscess developed at the site of the lodgment of the experimental embolus.