Characteristics of the study population by central venous pressure quartiles.

CVP: central venous pressure; IAP: intra-abdominal pressure; MAP: mean arterial pressure; APP: abdominal perfusion pressure; HR: heart rate; Ascites: moderate-to-large fluid collections in the peritoneal cavity detected by B type ultrasonography or CT scans; APACHE II score: Acute Physiology and Chronic Health Evaluation II score; BE: base excess; CT grade: according to Balthazar's methods; Local complication: including pancreatic necrosis, pseudocyst and abscess. P value*: Kruskal Wallis rank sum test was used to examine the significance if the variable was continuous. If theoretical number of the enumeration data <10, Fisher's exact test was used to calculate the significance. [mean (SD) and median (min-max) or n(%)] Characteristics of the study population by central venous pressure quartiles.