CV Directions Vol. 2, No. 2 | Page 14

CV  after operation for intra-abdominal catastrophe, most of which were rAAA. Eighteen of 23 survived. Abdominal wound closure for rAAA patients, all of whom were repaired by open techniques, was achieved at a mean of 4 days. Graft infection was not observed in this series of patients with a mean follow up of 53 months. A more recent study by Acosta et al. [20] evaluating the fascial closure rate of patients treated with an open abdomen utilizing vacuum and mesh-mediated traction techniques did identify a single patient with an aortic stent graft infection. In their study, 111 patients were treated with the combined vacuum and mesh-mediated traction technique (VAWCM), and of these 45 patients were treated secondary to vascular disease. The authors reported a mortality of 29.7%, median time to closure of 14 days, a 76.6% primary fascial closure rate overall in their intention-to-treat analysis, as well as an 89% fascial closure rate in per-protocol analysis. Factors associated with failure of closure included development of intestinal fistula and >14 days of open abdomen treatment. A single patient of 30 (3%) reported with repair of a rAAA developed an aortic graft infection. However, no other information specifically pertaining to this single patient was presented in their analysis. Risk factors for development of ACS in association with REVAR reported by Mehta et al. [1] include aortic balloon occlusion, massive transfusion, coagulopathy, and conversion to an aorto-unilateral device. In 6 of 30 patients, in this group’s initial experience, treated by REVAR, the diagnosis was made in 4 at the time of the index procedure. Decompressive laparotomy was immediately performed and 2 of the 4 survived. Death was observed in 2 patients in whom the diagnosis and decompressive laparotomy were delayed. Based on this experience, on-table decompressive laparotomy was recommended for patients with abdominal distention, signs of organ failure, and risk factors for ACS regardless of intraoperative bladder pressure measurements. No clear recommendations have otherwise been established to guide the timing of decompressive laparotomy in the setting of REVAR. One note of caution, however, relates to the phenomenon of decompression bleeding with decompressive laparotomy in this setting. Marin et al. [31] reported one death due to this phenomenon and now take measures to close the site of rupture at the time of decompressive laparotomy. Coagulopathy may contribute to this phenomenon. 8. Management of the Abdominal Wound Many different techniques have been described for maintaining abdominal domain and eventually achieving closure, either by permanent mesh, absorbable mesh, tissue transfer, or closing fascia primarily [14]. 14 Table 4: Proposed classification of the open abdomen. Adapted from Bjorck et al. [35]. Grade Description 1A Clean OA without adherence between bowel and abdominal wall or fixity (lateralization of the abdominal wall) 1B Contaminated OA without adherence/fixity 2A Clean OA developing adherence/fixity 2B Contaminated OA developing adherence/ fixity 3 OA complicated by fistula formation 4 Frozen OA with adherent/fixed bowel; unable to close surgically; with or without fistula. Bozeman, Ross Our preference is to use a negative pressure, vacuum-pack system either with or without a mesh fascial bridge [17]. Advantages of using mesh sutured to the fascia, with bowel protected by underlying plastic sheeting and towels, include maintenance of abdominal domain, avoidance of dehiscence, and a theoretical avoidance of possible fistula formation when applying vacuum suction. Patients with a negative pressure dressing incorporating a mesh bridge can even be extubated and managed off the ventilator prior to definitive closure. At the time of definitive closure, the mesh is removed and fascia sewn together. Opponents of this technique argue that suturing mesh to fascia is unnecessary and may cause weakening or even necrosis of the fascia, subsequently decreasing fascial integrity at the time of definitive closure. When mesh is not used, we create a negative pressure dressing by placing a soft, fenestr FVB