Laparoscopic aortobifemoral bypass

Curva de aprendizado em cirurgia aórtica videolaparoscópica: estudo experimental em porcos

CONTEXTO: A cirurgia videolaparoscópica (CVL) vem evoluindo como alternativa cirúrgica menos invasiva para o tratamento da doença aterosclerótica oclusiva aorto-ilíaca e do aneurisma da aorta abdominal. Poucos estudos avaliaram objetivamente a curva de aprendizado com essa técnica em cirurgia vascular. OBJETIVO: Avaliar objetivamente os tempos e a evolução de cada passo cirúrgico e demonstrar a exeqüibilidade dessa técnica. MÉTODOS: Entre outubro 2007 e janeiro de 2008, dois cirurgiões vasculares iniciantes na CVL operaram, após cursos e treinamentos, seis porcos consecutivos, com dissecção aórtica e interposição de um enxerto de dácron em um segmento da aorta infra-renal abdominal, com técnica totalmente laparoscópica. RESULTADOS: Todos os tempos cirúrgicos foram decrescentes ao longo do estudo, apresentando redução de 45,9% no tempo total de cirurgia, 85,8% no tempo de dissecção da aorta, 81,2% na exposição da aorta, 55,1% no clampeamento total, 71% na confecção da anastomose proximal e 64,9% na anastomose distal. CONCLUSÃO: O presente estudo mostrou que os resultados técnicos satisfatórios da CVL vascular ocorreram somente após longa curva de aprendizado, que foi decrescente ao longo do tempo, à medida que aumentou a experiência e vivência com os materiais e com a visão não-estereoscópica. Essa técnica pode ser realizada com perfeição por cirurgiões vasculares desde que façam cursos especializados, com treinamento em simuladores e animais, e desde que busquem constante aprimoramento a fim de conseguir resultados similares aos obtidos com a cirurgia convencional.

Videoendoscopic thoracic aorta-to-femoral artery bypass in the pig

BACKGROUND

The thoracoscopic approach to the aorta has the advantages of easy aortic dissection, excellent inflow, improved exposure in the thorax without insufflation, and ability to employ both laparoscopic and traditional instruments. Our aim was to develop a thoracoscopic technique for descending thoracic aorta-to-femoral artery bypass (TAFB) in the pig that results in acceptable short-term survival and graft patency.

MATERIALS AND METHODS

Thoracoscopic TAFB was performed in 11 pigs. Using two-lung ventilation, the animals were placed in a 45 degrees left lateral semidecubitus position. A fan lung retractor, two dissecting ports, intercostal artery loops, and camera were placed through five 10- to 20-mm thoracoscopic incisions. After aortic dissection, an 8-mm graft was passed through a retroperitoneal tunnel. Rumel tourniquets were used for aortic occlusion after placement of a shunt. End-to-side endoscopic anastomosis was completed with knots tied extracorporeally. The left femoral anastomosis was completed under direct vision. Duplex ultrasound of the graft was done on postoperative days 1, 3, and 7.

RESULTS

Thoracoscopic TAFB was completed in all animals. Mean aortic anastomosis time was 57 min (range, 34-145); and mean cross-clamp time, 74 min (range, 53-155). Mean operative time was 310 min; the first six operations lasted longer than the last five (338 min vs 276 min, P < 0.04). Average blood loss was 611 ml (range, 250-1300). Two animals died due to anesthetic complications. One (11%) of the nine surviving pigs died on day 2 due to bleeding. Complications were paraplegia in one (11%) and graft thrombosis in another (11%).

CONCLUSIONS

Videoendoscopic TAFB can be completed in pigs with acceptable short-term patency and survival. Further experience in thoracoscopic techniques can make TAFB a feasible and low-risk option for selected patients with aortoiliac occlusive disease.

Retroperitoneal endoscopic ligation of lumbar and inferior mesenteric arteries as a treatment of persistent endoleak after endoluminal aortic aneurysm repair

A 74-year-old man receiving long-term anticoagulation therapy for intermittent atrial fibrillation had a type II endoleak after endovascular abdominal aortic aneurysm repair. During an 8-month follow-up, the endoleak persisted, and the aneurysm failed to decrease in diameter. By means of a left flank retroperitoneal endoscopic surgical approach, the aneurysm was dissected free, and the lumbar arteries emanating from the aneurysm, as well as the inferior mesenteric artery, were ligated with titanium clips. A postoperative spiral computed tomography scan depicted one pair of unclipped lumbar arteries just proximal to the aortic bifurcation. After immediate reoperation with the same approach, complete thrombosis of the aneurysm sac was radiographically confirmed.