Feasibility and accuracy of continuous intraabdominal pressure monitoring with a capsular device in human pilot trial

Background: Intrabdominal pressure (IAP) is an important parameter. Elevated IAP can reduce visceral perfusion, lead to intraabdominal hypertension, and result in life-threatening abdominal compartment syndrome. While ingestible capsular devices have been used for various abdominal diagnoses, their application in continuous IAP monitoring remains unproven. Method: We conducted a prospective clinical trial to evaluate the feasibility of IAP measurement using a digital capsule PressureDOT, an ingestible capsule equipped with wireless transmission capability and a pressure sensor, then compared its reliability with conventional intravesical method. Patients undergoing laparoscopic or robotic surgeries were recruited. During surgery, we created pneumoperitoneum by inflating CO2 into the peritoneal cavity and IAP was simultaneously monitored using both the ingestible capsules and intravesical measurements from Foley catheter. We assessed the feasibility of signal transmission and the accuracy of pressure measurements. Results: Six patients were enrolled in this pilot study. No adverse events were reported, and the average first-intake time was within 24 h. All capsules were successfully expelled, with an average excretion time of 81 h. In the summarized data, the mean IAPdot is 0.6 mmHg lower than the IAPivp, with a standard deviation of 1.68 mmHg. However, capsule measurements showed excellent correlation with intravesical IAP measurements, with an intraclass correlation coefficient of 0.916 (95% CI: 0.8821–0.9320). Conclusion: Our study demonstrates the feasibility and safety of using digital capsules for continuous IAP monitoring, providing the agreement between IAP measurements from digital capsules and conventional intravesical measurement within a near-normal pressure.