The role of the vascular surgeon in anterior retroperitoneal spine exposure: preservation of open surgical training.

OBJECTIVE: Open vascular surgical procedures have decreased since the advent of endovascular repair. Advances in spinal fusion techniques and artificial disc replacement have led to an increase in the need for anterior retroperitoneal exposure of the lumbar spine (ARES). Vascular surgeons participate as "exposure surgeons" for these cases due to their unique skills in dealing with retroperitoneal structures. We report a single center experience with this procedure and focus on injury pattern and preservation of open surgical training.
METHODS: Patients undergoing ARES over an 8-year period were identified from our vascular registry. A two-team approach involving a vascular surgeon and spine surgeon has been routinely employed. ARES was performed for anterior lumbar interbody fusion or total disc replacement. The intraoperative techniques of vascular manipulation were reviewed. The need for suture repair of vascular structures and the incidence and timing of serious vascular injury was recorded.
RESULTS: Four-hundred and five ARES procedures were performed. The levels exposed included L5-S1 alone (128), L4-5 (54), 4-5 and 5-S1 (139), and other combinations in 84 cases. The exposure involved the L4-5 disc in 243 cases (60%). Exposure of L4-5 was accomplished above the left common iliac artery (CIA) in 44%, between the left CIA and common iliac vein (CIV) in 45%, and below the left CIV in 11%. Minor vascular injuries (all venous) needing suture repair occurred in 24% of cases overall. Minor vascular injuries occurred during both exposure (43%) and instrumentation (57%). Minor vascular injuries were significantly more frequent in cases involving the L4-5 disc than in those not involving L4-5 (31.7% vs 11.1%, P < .001). Serious, life-threatening, vascular injuries occurred in 12 patients (3%), all during instrumentation, and included left CIV laceration (seven cases), right CIV laceration (two cases), and inferior vena cava laceration, distal aortic plaque disruption and left CIA laceration in one case each. There was no association between body mass index, prior surgery, or type of instrumentation and the occurrence of minor or major vascular injuries. Postoperative vascular complications included three deep vein thromboses; two of which occurred in patients with CIV laceration.
CONCLUSION: Vascular expertise is important in anterior retroperitoneal lumbar spine exposure. Minor venous injuries frequently occur during exposure and instrumentation. Significant vascular injuries, while rare, occur during instrumentation, therefore the vascular surgeon should remain present throughout the entire procedure. The vascular manipulations required during exposure of the L4-5 disc offer an excellent opportunity for open vascular surgical experience. Vascular surgeon involvement in these cases allows for prompt repair of vascular injuries and provides opportunities for the vascular surgery resident to augment his/her open surgical training.