Intra-abdominal hypertension and the effect on renal function.

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are increasingly recognized in critically-ill patients. They are independently associated with mortality and organ dysfunction. The kidney is especially vulnerable to the effect of increased intra-abdominal pressure (IAP) due to its anatomical position and blood supply. Several animal and human studies have provided insights into the mechanism of renal dysfunction in IAH. It is now also accepted that the adverse effects of elevated IAP on renal function can occur at lower levels of IAP, long before development of overt ACS. The mechanism of renal impairment in ACS is not yet completely understood, but there is evidence available that renal blood flow and/or altered hormone levels are involved.