Studies on the effects of sympathicoamines in asthma. Variability of effect from differing routes of administration.

We define asthma as a syndrome consisting of paroxysmal, recurrent and reversible partial obstruction of the lower bronchial tree resulting in the development of acute obstructive emphysema. Variability is a striking clinical feature of asthma both from patient to patient and in the same patient from day to day. The factors which produce bronchial obstruction in asthma are mucosal edema and congestion, bronchial inflammation, viscid secretion and bronchial muscle spasm. However, there is controversy regarding the relative importance of each one of these factors. From clinical observations it appears that the relative significance of these factors is not constant, but may be quite different in different patients, and may also show variation from time to time in any one patient. This accounts for the differing severity and response to treatment of asthma. There is also no clear cut evidence as to the precise method by which epinephrine and the other sympathicoamines act to relieve human bronchial asthma. The antispasmodic action of epinephrine in relieving bronchial muscle spasm produced by vagal stimulation or drugs and the capillary constricting effects of epinephrine have been invoked.3 Best and Taylor2 and Goodman and Gillman3 emphasize the antispasmodic effects of epinephrine. It has been pointed out4 that epinephrine has a variable effect on bronchiolar musculature, depending on its tone. If the muscle is constricted, relaxation results. If it is relaxed completely, contraction of the muscle occurs. However, clinicians, such as Cooke,’ Fineberg6 and Lowell7 emphasize the vasoconstrictive effects of epinephrine on congested and edematous bronchial mucous membrane. This study undertakes an evaluation of the results of differing routes of administration on the effectiveness of some sympathicoamines in relieving acute asthmatic episodes. From the Chest and Allergy Departments. Michael Reese Hospital.