The effects of increased abdominal pressure on various organ systems has been noted over the past century. Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) have been identified as a cause of organ dysfunction and mortality in several subsets of critically ill patients. The staged abdominal repair operation popularly known as STAR operation is a technique of temporary closue of abdomen during primary surgery followed by a second surgery 24 to 48 hours later ending in final aponeurosis to aponeurosis closure of abdomen.. In abdominal compartment syndrome;this operation, is gaining popularity because it is life saving in critically ill patients and has lower complication rate as well.Intra-abdominal pressure (IAP) is the steady pressure within the abdominal cavity.For critically ill patients, an IAP of 5 to 7 mm of Hg is considered normal. Intra-abdominal pressure (IAP) is graded as follows : Abdominal perfusion pressure (APP) is calculated as the mean arterial pressure (MAP) minus the IAP i.e APP = MAP -IAP. Multiple regression analysis have found that APP is better than other resuscitation endpoints such as arterial pH, base deficits, arterial lactate, and hourly urinary output for predicting outcomes.A target APP of at least 60 mmHg is correlated with improved survival from IAH and ACS.Intra-abdominal hypertension (IAH) is defined as a sustained intra-abdominal pressure ˃12 mm of Hg. IAH impairs the function of nearly every organ-system. IAH decreases cardiac output by impairing cardiac function and reducing venous return. It causes cephalad movement of the diaphragm which leads to reduced ventricular compliance and reduced contractility. IAH obstructs blood flow in the inferior vena cava leading to diminished venous flow from the lower extremities resulting in formation of peripheral edema and increase risk of deep vein thrombosis.It causes alveolar barotrauma in mechanically ventilated patients. It reduces chest wall compliancewhich further lead to arterial hypoxemia, hypercarbia and pulmonary infections. It leads to impairment of renal function by causing renal artery vasoconstriction and renal vein compression. Gut is very sensitive to rise in intra abdominal pressure. . IAH compresses thin-walled mesenteric veins which impairs venous flow from the intestine and causes intestinal edema. The intestinal swelling further increases intraabdominal pressure, initiating a vicious cycle.The end result is worsened hypoperfusion, bowel ischemia, decreased intramucosal pH, and lactic acidosis.Abdominal compartment syndrome defined as a sustained intra-abdominal pressure > 20 mm Hg with or without abdominal perfusion pressure [APP] of < 60 mm Hg that is associated with new organ dysfunction.For clinical purposes, ACS is better defined as IAH-induced new organ dysfunction, without strict intra-abdominal pressure threshold..Patients with intra-abdominal pressure below 10 mm Hg generally do not have ACS. ACS can be primary due to injury or disease in abdomino pelvic organs, secondary due to condi...