Blocking Effect of Ethyl Chloride Spray on Cardiac Pain Induced by Ergonovine.

Abstract

Thirty-six tests were done on 7 patients who had effort angina and a normal resting ecg., and who on intraven. admn. of ergonovine maleate (0.1-0.4 mg.) promptly developed both ecg. changes characteristic of coronary insufficiency and pain in the chest, shoulder, arm, or neck like that induced by walking. Intraven. injn. of physiol. saline soln. caused neither pain nor ecg. changes. Nitroglycerin (0.4-0.6 mg.) given sublingually just before ergonovine prevented both pain and ecg. changes in 5 of 7 patients. When ethyl chloride spray was applied just before ergonovine, it prevented the predicted pain response to ergonovine in 4 of 7 patients, but not changes in the ecg. When ethyl chloride spray was applied after ergonovine had been injd. and when pain had appeared, it relieved pain completely in 4 of 6 patients and partially in 2, despite persistence of ecg. changes until nitroglycerin was given. These results afford additional evidence of the previously reported clinical efficacy of ethyl chloride spray in relieving chest pain attributable to the somatic component of cardiac pain. In addition, results indicate that a standardized visceral pain may be prevented by altering the flow of nerve impulses from the somatic reference zone.