Bladder Evacuation in Paraplegic Dogs by Direct Electric Stimulation

Abstract

EARLY RESULTS of direct electric stimulation of the urinary bladder in paraplegic dogs have been previously reported.^1,2 Two stainlesssteel wire electrodes were implanted in the smooth muscle itself for application of a train of biphasic square waves generated by a stimulator. Parameters of the most effective stimulus were one to six milliseconds' duration and 15 to 35 cycles per second frequency. The best response was obtained with 4 msec and 20 cps (Fig 1). This corresponds rather well with the findings of Burghele and associates,³ as well as with those of Bradley et al.⁴ In experiments on 12 normal dogs and 17 animals whose lumbar spinal cords had been transected, a catheter was inserted through a small cystotomy during surgery. Intravesical pressure, registered with a strain-gauge and recorder, exceeded 40 cm of water with 2.5- to 10-v stimuli in all but two dogs. In most of the 17 paraplegic