Frequency, risk factors, and management of perigraft seroma after open abdominal aortic aneurysm repair.

ABSTRACT

OBJECTIVE: Perigraft seroma (PGS) causing enlargement of the native aneurysm sac after open abdominal aortoiliac aneurysm (AAA) repair is a rarely recognized complication with unknown clinical consequences. This study was undertaken to determine the frequency of PGS, identify associated risk factors, and review resulting complications and their management strategies. METHODS: Charts of all patients who underwent open AAA repair at our institution from 1995 to 2009 and had at least one postoperative abdominal cross-sectional imaging study (the study subjects) were retrospectively reviewed. PGS was defined as a perigraft fluid collection present > 3 months postoperatively, ≥ 3-cm in diameter and having a radiodensity ≤ 25 Hounsfield units on computed tomography (CT). Patient records were reviewed for demographics, comorbidities, operative and postoperative variables, and long-term outcome. RESULTS: Of the 111 study subjects identified, 13 had aortic reconstruction with Dacron grafts and 98 with polytetrafluoroethylene (PTFE) grafts. Twenty patients (18%) had PGS, all of whom had PTFE grafts (20 of 98; 20.4%). Mean age was 68.5 years and mean aneurysm diameter preoperatively was 6.4 cm (range, 4.0-10.9 cm). The average time from AAA repair to PGS detection was 51 months (range, 4-156 months). PGS averaged 6.0-cm in diameter (range, 3.0-11.0 cm). Multivariate analysis revealed that the following factors were associated with PGS development diabetes (odds ratio [OR], 3.5; 95% confidence interval [CI], 1.1-21.2; P = .013), smoking (OR, 5.6; 95% CI, 0.73-33.74; P = .01), anticoagulation (OR, 7.2; 95% CI, 2.6-63.3; P = .003), bifurcated graft reconstruction (OR, 8.0; 95% CI, 2.6-94.1; P = .017), and left flank retroperitoneal approach for repair (OR, 7.1; 95% CI, 1.9-26.5; P = .003). Four patients (4 of 20; 20%) required intervention for PGS-related complications 3 patients for symptomatic PGS expansion (1 patient with rupture) and 1 patient for acute limb ischemia secondary to graft limb compression and thrombosis. Two patients had open exploration, sac evacuation/reduction, and graft replacement with a Dacron graft 1 patient for a ruptured aneurysm sac and 1 patient for persistent pain associated with sac enlargement. A third patient underwent a failed CT-guided drainage for abdominal pain and was subsequently treated with partial graft excision. The patient with acute limb ischemia was treated with catheter-directed thrombolysis and graft limb stenting. CONCLUSION: PGS after open AAA repair occurs more frequently than previously reported. Complications requiring intervention can occur in up to 20% of patients with PGS. A variety of treatment modalities can be used to deal with the complications. Earlier CT surveillance is advised after open AAA repair with a PTFE graft if symptoms are suggestive of PGS development.