Abdominal compartment syndrome (ACS) occurs when the abdomen becomes subject to increased pressure reaching past the point of intra-abdominal hypertension (IAH). ACS is present when intra-abdominal pressure rises and is sustained at > 20 mmHg and there is new organ dysfunction or failure. ACS is classified into three groups: Primary, secondary and recurrent ACS. It is not a disease and as such it occurs in conjunction with many disease processes, either due to the primary illness or in association with treatment interventions. Specific cause of abdominal compartment syndrome is not known, although some causes can be sepsis and severe abdominal trauma. Increasing pressure reduces blood flow to abdominal organs and impairs pulmonary, cardiovascular, renal, and gastro-intestinal (GI) function, causing obstructive shock, multiple organ dysfunction syndrome and death. Causes
Peritoneal tissue edema secondary to diffuse peritonitis, abdominal trauma
Fluid therapy due to massive volume resuscitation
Retroperitoneal hematoma secondary to trauma and aortic rupture
Peritoneal trauma secondary to emergency abdominal operations
Reperfusion injury following bowel ischemia due to any cause
Retroperitoneal and mesenteric inflammatory edema secondary to acute pancreatitis
Ileus and bowel obstruction
Intra-abdominal masses of any cause
Abdominal packing for control of bleeding
Closure of the abdomen under undue tension
Ascites (intra-abdominal fluid accumulation)
Acute pancreatitis with abscesses formation

Pathophysiology
Abdominal compartment syndrome occurs when tissue fluid within the peritoneal and retroperitoneal space (either edema, retroperitoneal blood or free fluid in the abdomen) accumulates in such large volumes that the abdominal wall compliance threshold is crossed and the abdomen can no longer stretch.
The poor outcome relates not only to abdominal compartment syndrome itself but also to concomitant injury and hemorrhagic shock. The surgical decompression of the abdomen remains the treatment of choice of abdominal compartment syndrome; this usually improves the organ changes and is followed by one of the temporary abdominal closure techniques in order to prevent secondary intra-abdominal hypertension. Surgical decompression can be achieved by opening the abdominal wall and abdominal fascia anterior in order to physically create more space for the abdominal viscera. Once opened, the fascia can be bridged for support and to prevent loss of domain by a variety of medical devices (Bogota bag, artificial bur, and vacuum devices using negative pressure wound therapy). References
External links

openabdomen.org
wsacs.org