Wireless bioacoustic sensor system for automatic detection of bowel sounds

Due to anesthesia loss of gastrointestinal motility is a common situation for patients who underwent abdominal surgery. The aim of this study is to present the bioacoustic sensor system developed for real time detection of recovery of gastrointestinal tract motility by observing bowel sounds and for bowel sound signal analysis. Different than other studies, in this study, in order to be able to attenuate environmental noise, bowel sounds were observed using two microphones. Bowel sounds were observed between 100 Hz and 1 kHz with maximum amplitude of 20mV. The signal was amplified 121 times and final signal amplitude was between 0-2, 4V. Similarly, environmental noise observed by the second microphone was amplified. Both of the signals were digitized using 12 bit analog digital converter of the ZigBee module (JN5139-Z01) and were transferred with wireless connection. With the developed software, spectral and temporal properties were obtained and presented in real-time. Finally, a stethoscope shaped box was designed for easy use of the sensor system.