Objective. We have developed an integrated Fecobionics device to assess pressures, orientation and bending simultaneously during defecation. This study assessed the feasibility of the Fecobionics device in pigs.Methods. Ten Yorkshire pigs (male, 50–60kg) were divided into groups that was euthanized immediately after the experiment (acute group, n=5) or lived for 2 weeks before the pigs were euthanized (chronic group, n=5). Fecobionics is a bendable probe that contains pressure sensors, motion processing units (MPUs), and electronic circuits. The probe was 13cm long, 13mm OD and contained a bag for distension. The pigs were lightly restrained in a sling. The device was inserted manually through an anoscope into the rectum within half hour after the pig had a normal defecation. The bag was filled with 20–50 ml of saline to provide an urge to defecate. Behavior and signs of discomfort was evaluated during and after the defecation. Pressures, orientation and bending data were collected during defecation. Both the rectum and the anal canal were excised after euthanization for mucosal gross morphological observation and histological examination. Devices were tested after the expulsions for any damage to the electromechanical system, the core and bag.Results. The pigs paid little attention to device insertion if they were distracted by food. Often the pigs became a bit agitated after eating and defecated the device at this point. The device was defecated from few minutes up to 1h after insertion (average 12min). The pressure sensors at the two ends and inside the bag showed simultaneous pressure increase when the pigs contracted the abdominal muscle. The defecation pressure was usually in the range 80–100cmH2O if the pig was not agitated. Device bending was less than 20 degrees during defecations, indicating that the pig does not exhibit an anorectal angle like humans. Fecobionics was slowly pushed out in 10–40 seconds, often with the front hanging from the anus for some time before being dropped. The recovered devices had intact surfaces without exposed electronics. In two cases the bag had a small leak. One device stopped working after being defecated and had a broken wire, likely due to damage when it dropped to the floor. Mucosal damage, bleeding and inflammation were not found in gross morphological observation and histological examination in the acute or chronic groups.Conclusions. Fecobionics is a safe device providing novel defecatory measurements under physiological conditions.Support or Funding InformationNIH SBIR phase 1 grant R43DK112543 and NIH SPARC OT2OD025308
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