A Novel Method (CiMON) for Continuous Intra-Abdominal Pressure Monitoring: Pilot Test in a Pig Model

Background. Intravesical pressure (IAP(ivp)) measurement is considered to be the gold standard for assessment of intra-abdominal pressure (IAP). This study evaluated a new minimally invasive IAP monitoring device (CiMON) against three other devices in a wide range of clinically relevant IAP and in different body positions in healthy pigs. Methods. The CiMON catheter (IAP(CiM)) and another balloon-tipped catheter (IAP(spie)) were positioned into the stomach. Fluid-filled catheters were used for direct intraperitoneal (IAP(dir)) and IAP(ivp) measurement. Both in supine and 25° head-of-bed positions, IAP was increased from baseline to 30 mmHg. At every IAP level, 4 IAP measurements were recorded simultaneously. Mean differences and the limits of agreement were calculated. Results. Bias between IAP(CiM) and IAP(spie) was nearly zero with very good agreement, both in supine and 25° position. In supine position, IAP(CiM) slightly overestimated IAP(ivp) and IAP(dir) by 1.5 and 2.1 mmHg with reasonable agreement. In 25° position, IAP(CiM) underestimated IAP(ivp) and IAP(dir) by 1.0 and 0.5 mmHg, again with reasonable agreement. Conclusions. Agreement between IAP(CiM) and IAP(spie) was very good, while good-to-moderate agreement exists between IAP(CiM) and IAP(dir) or IAP(ivp). Simplicity, continuous monitoring, and the combination with a feeding tube should lead to further clinical studies, evaluating this new CiMON device.