Injections of Caffeine and Adrenalin and Subsequently Staphylococcus Aureus Suspensions on Myocardium and Endocardium.

Abstract

Fleisher and Loeb have shown that a single intravenous injection of a mixture of .025 gm. caffeine sodium benzoate and .2 cc. adrenalin chloride causes a gross myocardial lesion in the left ventricle and papillary muscle of the left ventricle in rabbits, in about 60 per cent of cases. We have confirmed their observations, and have in addition observed a lesion in the left auricle which follows these injections in some cases. In order to rule out the possibility that these may be spontaneous lesions, and in order to analyse the functional effects of these myocardial changes, a series of rabbits was examined electrocardiographically before and after these injections. We may only state here that the cardiac condition is not the result of previous spontaneous myocardial disease. Experiments were carried out to determine whether this lesion produced by caffeine and adrenalin injections would render the rabbit's heart more susceptible to abscess formation when, subsequently, a pyogenic organism in culture is injected intravenously. For this purpose 24 rabbits were injected with a single dose each of the caffeine and adrenalin mixture. Then at varying periods afterwards, each was injected with 1 cc. of a 48 hour bouillon culture of a laboratory strain of living Staphylococcus aureus of a sufficient virulence to cause the production of abscesses in the kidneys in a large number of cases without causing the death of the animals within the following three weeks. The rabbits were killed at varying periods following these injections and the organs examined grossly and microscopically. Twenty-three of the 24 animals showed the gross myocardial lesion which usually follows caffeine and actrenalin injections. In addition, 8 had abscesses in the myocardium. Of these 8, 6 showed a single abscess in or in very close proximity to the caffeine and adrenalin lesion in the myocardium of the left ventricle.