Abdominal Compartment Syndrome (ACS) after Abdominal Aortic Aneurysm (AAA) Open Repair

Abstract

INTRODUCTION: 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 organic dysfunction and may lead to permanent impairment of function”.

MATERIALS AND METHODS: Between June 2007 and June 2008 all patients recovered to our Institution for Abdominal Aortic Aneurysm (AAA) underwent intermittent intra-abdominal pressure monitoring using intra-vescical catheter. Pressure data were registered before abdominal incision, during intervention, at closure of abdominal wall and at 6, 12, 24 and 36 hours in post-operative course. Rise in Intra-Abdominal Pressure (IAP) more then 20 mmHg was considered for surgical decompression.

RESULTS: Twenty three cases of AAA were treated surgically. Fourteen underwent elective repair and 9 emergency/urgency repair; in the emergency/urgency group, 8 were symptomatic without rupture signs and one case presented TC rupture signs. In the last case we registered preoperatively IAP more than 20 mmHg treated with only skin tension-free suture. No perioperative mortality was registered.

DISCUSSION: ACS have been increasingly recognized as causes of significant morbidity and mortality over the last years after AAA surgery. ACS was recently classified from the World Society of the Abdominal Compartment Syndrome (WSACS) as primary, secondary and recurrent. ACS was recognized as major prognostic factor after AAA repair. ACS incidence ranges from 4 to 12%. Even if ACS etiological bases are not well known, principal risk factor for ACS development after AAA repair are massive fluid resuscitation infusion and aortic clamping. IAP values, and subsequent possibility of ACS development, are superior after ruptured AAA repair than elective repair. Also in our study, even if limited by small number of cases, we registered differences in IAP value during emergency/urgency repair and elective repair. Patients management with rising IAP, or at risk of ACS development, should be mandatory decompressed for IAP higher than 20 mmHg or also with inferior values if in association to organ dysfunction. IAP measurement can be performed directly or indirectly and all these techniques have as objective IAP monitoring before its clinical manifestation in ACS.

CONCLUSION: ACS can be considered a reliable predictive factor for aneurysm surgery outcome. Prevention of the ACS, with early recognition of rising IAP and urgent intervention to decompress the tense abdomen can lead to mortality reduction after aneurysm repair. The measurement of IAP is simple and non-invasive, and should be a routine component of physiological monitoring in patients following ruptured aneurysm repair in association with hypotensive hemostasis.