Inhibitory effects of a smartphone-controlled wearable transcutaneous tibial nerve stimulation device on bladder reflexes in anesthetized cats.

Abstract

To explore the inhibitory effects of a novel, smartphone-controlled, and wearable tibial nerve stimulation device on nonnociceptive and nociceptive bladder reflexes in anesthetized cats and to compare the stimulus results of two current waveforms outputted by this new stimulator. A novel, intelligent tibial nerve stimulator was put on the ankles of 14 cats and controlled by a mobile application. Cystometrograms (CMGs) were performed repeatedly by infusing 0.9% normal saline (NS) and 0.5% acetic acid (AA) through a urethral catheter. Inhibitory effects were explored by measuring the bladder capacity (BC) in two areas: (1) on nonnociceptive bladder reflex (infused with NS) and on nociceptive bladder reflex (filled with AA to induce overactive bladder [OAB] model); and (2) under the stimulation of two different current waveforms (waveforms A and B). In Group 1, the BC of AA-induced OAB (41.48 ± 8.40%) was significantly different compared with the capacity of a NS-infused bladder (104.89 ± 1.32%, p < 0.05). Both NS-filled (151.35 ± 5.71%, p < 0.05) and AA-instilled (71.41 ± 9.34%, p < 0.05) bladder volumes significantly increased after tibial nerve stimulation (TNS). In Group 2, the BC increased to 166.18 ± 15.17% (p = 0.026) and 127.64 ± 13.00% (p = 0.239), respectively, after TNS with waveforms A and B current. Results revealed that this novel, smartphone-based, wearable, and wireless tibial nerve stimulation system could inhibit the micturition reflex on physiological condition, serving as a potential option for OAB treatment. In addition, the waveforms of stimulation current had an important influence on the effects of TNS.