Continuous monitoring of intra-abdominal pressure: cumulative pressure exposure predicts early acute kidney injury in animal model.

BACKGROUND

Elevated intra-abdominal pressure (IAP) causes organ dysfunction, particularly acute kidney injury (AKI). Current intermittent IAP monitoring methods are inadequate for capturing the dynamic fluctuations. We hypothesize that the cumulative exposure to elevated IAP over time is a predictor of organ injury.

METHODS

We evaluated the feasibility of a novel capsular sensor (PressureDOT, PDT) for continuous IAP measurement in six anesthetized porcine subjects. Controlled intra-abdominal hypertension (IAH) was induced using progressive CO2 insufflation. We calculated the cumulative intra-abdominal pressure exposure (cIAPe), defined as the integrated area under the curve of IAP values exceeding 12 mmHg over time. Serial serum creatinine (Cr) estimated glomerular filtration rate (eGFR), and other organ markers were tracked.

RESULTS

Continuous and high-resolution IAP monitoring was achieved in all subjects. Exposure to IAH significantly increased mean serum Cr (1.69 ± 0.19 to 2.16 ± 0.31 mg/dL; p = 0.01) and reduced eGFR (41.33 to 25.00 mL/min; p < 0.001). A linear correlation was demonstrated between increasing cIAPe and rising Cr ratio (R2 ranging from 0.84 to 0.97). Critically, changes in Cr and eGFR reduction were statistically significant across progressive cIAPe phases (p = 0.048 and p < 0.001, respectively).

CONCLUSION

The use of continuous IAP monitoring by PDT is feasible in this controlled porcine model. Our findings suggest that cIAPe may be a quantifiable marker associated with early renal impairment. Although early detection of physiological renal impairment consistent with early AKI criteria is promising, validation in larger animal studies and future human trials is necessary to determine clinical relevance.