Table 3. Adjusted Effect of IAP on CVP [β (95%CI) P value].

	correlation coefficient (β)	95%CI	P value
IAP group 1 (IAP≤15.7)
Model I	0.2	-0.01, 0.41	0.059
Model II	0.22	0.01, 0.42	0.042
Model III	0.18	-0.03, 0.39	0.094
IAP group 2 (IAP>15.7)
Model I	-2.14	-3.42, -0.85	0.005
Model II	-1.9	-2.73, -1.06	<0.001
Model III	-2.128	-2.30, -1.294	<0.001

Outcome variance: CVP (cmH₂O); risk factor: IAP (mmHg).

Model I: Multiple regression model (no adjusted related risk factors);

Model II: Multiple regression model adjusted APP level;

Model III: Multiple regression model adjusted MAP level.

CVP: central venous pressure; IAP: intra abdominal pressure; MAP: mean arterial pressure; APP: abdominal perfusion pressure.