Abstract
In order to develop the electrophrenic respirator, the voltage and the current threshold of the phrenic nerve of the dog and the impedance between electrodes are measured after implantation of nerve electrodes for a period of over a month. The thresholds rise in several postoperative days and reach steady levels. The mean values of the steady levels of the voltage and the current threshold are approximately 200 mV and 400μA respectively, and that of the impedance is about 400 Ω. A mercury-battery-operated implantable electrophrenic respirator with low power consumption was designed and assembled on the basis of these data. The power consumption of this device is about 300 μW so that the theoretical life of the battery is calculated roughly at 220 days. Continuous electrophrenic respiration is applied by the device for a few weeks with the results of slight increases in the thresholds and a slight decrease in the tidal volume.
