The Abdominal Compartment Syndrome (ACS) after Abdominal Aortic Aneurysm (AAA) open repair

Abstract

Objective: The abdominal compartment syndrome (ACS) is a ‘condition in which increased tissue pressure in a confined anatomic space, causes decreased blood flow leading to ischaemia and dysfunction and leading to permanent impairment of function’. Methods: Between June 2007 and June 2008 we treated surgically 23 cases of AAA (14 in election and nine in emergency), with indirect intra- abdominal pressure (IAP) monitoring (intra-vescical catheter). Mean age was 68 (64–84) years, 19 males and 4 females. Mean transverse diameter was 6.2 cm (5.5–9.0). Preoperative diagnostic procedure was ultrasound and tomography when possible. All patients were managed in hypotensive hemostasis (restricting fluids and keeping blood pressure around 90 mmHg). Rise in IAP >20 mmHg was considered for surgical decompression. In one case we registered preoperatively IAP >20 mmHg treated with only skin suture. No 30-days mortality was occurred. Results: Is possible to distinguish an acute ACS, secondary to a rapid rise in IAP, and a chronic (compensated by increased abdominal wall compliance). In vascular patients ACS may occur following free intraperitoneal or contained retroperitoneal aneurysm rupture. ACS was defined as ‘killer number one’ in rAAA treatment. Aggressive ACS treatment has determinedin Mayer experience overall 30-day mortality decreased by two-thirds to 12% in 94 patients treated by emergency EVAR for rAAA and 33% for 107 patients treated by open repair over the past 10 years. Management for patients with raised IAP, or at risk of developing ACS following aortic surgery, is to consider urgent decompression in any patients with IAP over 20 mmHg or at lower pressures associated with worsening organ dysfunction. The rise of IPA >20 mmHg is the determinant of ACS that may lead to ischemia and dysfunction of the principal organ and system leading to Multi-Organ Failure. Measurement of IAP may be performed directly (intra-abdominal catheter) or indirectly (intra-vesical. All this methods have as objective IPA monitoring before its clinical manifestation. We used intra-vesical catheters for IPA monitoring and in one case it leads to a surgical decompression. Conclusions: ACS can be a reliable predictive factor for aneurysm outcome. Prevention of ACS, with early recognition of rising IAP and urgent intervention to decompress the tense abdomen can lead to mortality reduction after aneurysm rupture. IAP measurement IAP is simple and non-invasive, and should be a routine component of physiological monitoring in patients after rAAA in association with hypotensive hemostasis.