Correlation between different methods of intra-abdominal pressure monitoring in varying intra-abdominal hypertension models

Abstract

BACKGROUND : Advances in intra-abdominal pressure (IAP) measurement have enabled better monitoring and physiological manipulation of patients with intra-abdominal hypertension or abdominal compartment syndrome. This study aimed to determine the correlation between transvesical (TV), transgastric (TG) and direct transperitoneal (TP) IAP monitoring at different IAPs in porcine models. OBJECTIVES : To assess the statistical agreement between TV, TG and TP pressure monitoring in a pneumoperitoneum and an intestinal obstruction intra-abdominal hypertension model at different IAPs. METHODS : Fifty-nine pigs were divided into six groups: a control group (Cr; n=5), three pneumoperitoneum groups at pressures of 20 mmHg, 30 mmHg, and 40 mmHg (Pn20, Pn30, Pn40; n=40), and two intestinal-occlusion groups at pressures of 20 mmHg and 30 mmHg (Oc20, Oc30; n=14). IAP was simultaneously measured in each pig using the three methods at different times. The control group did not have any intervention to increase the IAP. Intra-class correlation was used to assess agreement between the methods. RESULTS : At pressures >20 mmHg, all three methods showed good correlation with each other (Pn20=0.87; Pn30=0.96; Pn40=0.88; Oc20=0.69; Oc30=0.86). Correlation between TP and TG (Cr=0.0; Pn20=0.85; Pn30=0.94; Pn40=0.90; Oc20=0.78; Oc30=0.78); TP and TV (Cr=0.0; Pn20=0.83; Pn30=0.95; Pn40=0.86; Oc20=0.59; Oc30=0.88); and importantly between TV and TG (Cr=0.0; Pn20=0.95; Pn30=0.98; Pn40=0.88; Oc20=0.69; Oc30=0.91) was good. CONCLUSION : All three measurement methods showed good correlation at pressures >20 mmHg and were unaffected by the type of IAP model. These results suggest that either transvesical or transgastric pressure measurements can be used for IAP measurement when TP pressures are >20 mmHg.