Electrophrenic Respiration

Abstract

Artificial respiration using electrical stimulation of the phrenic nerves has been developed. A gradual increase of voltage produces smooth diaphragmatic contraction. Electrophrenic respiration was studied in the rabbit, cat, monkey, and man. A smooth diaphragmatic contraction, resembling that seen during spontaneous respiration, followed gradually increasing voltage applied to the phrenic nerve. The ventilation accomplished was directly proportional to the peak voltage. The spontaneous minute volume, arterial blood O2 and CO2 tensions of animals and man could be duplicated by electrophrenic respiration with submaximal stimulation of one phrenic nerve in the absence of spontaneous respiration. Max. stimulation of one phrenic nerve can produce overventilation and alkalosis. Bilateral maximal stimulation produced further decrease in arterial blood CO2 tension and might triple the spontaneous minute volume. An adequate minute volume and normal arterial blood O2 and CO2 tensions were maintained in the cat for 22 hrs. in the absence of spontaneous activity. The anesthetized animal and unanesthetized man relinquish control of respiration when electrophrenic respiration starts. The technic sustained life for 52 hrs. in a 5-yr.-old boy with complete respiratory paralysis following rupture of a cerebral aneurism.