Pancreatitis associated ascetic fluids(PAAF) gather with the beginning of SAP and induced IAP(intra-abdominal pressure) increasement.With an excess of 12mmHg ,IAP presents as IAH(intra-abdominal hypertension) and when a ≥20mmHg IAP accompanied with at least one organ's dysfunction it is ACS(abdominal compartment syndrome).Previous recommended theraphy of ACS is laparotomy.However,with inherited advantages such as ease-to-operate and minimal invassiveness, early stage mini-invasive abdominal drainage therapies , for example, percutaneous catheter drainage(PCD) instructed by ultrasound or CT ,have shown a promised future in recent years. It is reported that patients acquired PCD decreased 81% in operation rate compared to those who did not and had lower mortality rate. Whereas, the operation flow of early stage mini-invasive abdominal drainage remains controversial, and whose validity calls for evidence from large-scale clinical trials.