Dilatation of the aorta forming an aneurysm occurs in about 2% of men over the age of 65 (it is less common in women). Small aneurysms may present no problems, but some continue to grow, and larger aneurysms can leak or rupture. This carries a high risk of mortality, even when it is possible to offer emergency surgery. Preventive treatment is often advised for patients with aneurysms that represent an appreciable rupture risk.
The traditional treatment for abdominal aortic aneurysm is open surgical repair. The aneurysm is opened and a graft is then sewn in above and below the weakened area to allow normal blood flow. A less invasive approach is now commonly used, involving endovascular stent graft placement via the femoral arteries, but not all aneurysms are suitable for endovascular treatment.
Laparoscopic repair of abdominal aortic aneurysm can be done by hand-assisted laparoscopic surgery (HALS) or by the technically more demanding totally laparoscopic surgery (TLS). In HALS, a midline minilaparotomy incision is made for insertion of one of the surgeon's hands to aid the procedure. In both techniques, small skin incisions are made for insertion of a laparoscope and instruments to guide and/or perform the repair. Lumbar arteries and the inferior mesenteric artery are dissected and clipped. Clamps are applied above and below the aneurysm, the sac is opened and thrombus removed. A prosthetic vascular graft is anastomosed to the proximal and distal ends of the aorta. The aneurysm wall and the posterior parietal peritoneum may be closed to cover the graft.
In three non-randomised controlled trials, mean hospital length of stay (LOS) was 5.9 (HALS), 6.2 and 6.3 (TLS) days, compared with 9.4, 10.0 and 10.2 days following open repair. One non-randomised controlled study reported that mean LOS was broadly similar following HALS (7.4 days) and endovascular stenting (6.4 days).
In one case series, mean LOS was 5 days for TLS (n=131) and 7 days for HALS (n=215). In a second case series, mean LOS for HALS was reported as 4.4 days. There was a statistically significant difference in mean LOS between the first 30 patients (5.3 days) and the last 92 patients (4.1 days) treated at one institution (p=0.001). For more details, see the overview.
All Specialist Advisers considered this procedure to be novel and of uncertain efficacy. They considered key efficacy outcomes for this procedure to be successful complete repair, open conversion rates, operative time, intensive care unit and overall hospital LOS, patient quality of life, renal function and need for return to theatre. Some Specialist Advisers suggested that there would be longer operating times, particularly early in the learning curve.
Postoperative death rates following laparoscopic aneurysm repair have been reported as 3% (1 out of 29) and 4% (1 out of 24; HALS), and 5% (3 out of 60) and 10% (2 out of 20; TLS).
One non-randomised controlled trial reported that the rate of renal insufficiency was 2% (1 out of 60) following laparoscopic repair compared with 11% (11 out of 100) following open repair. Other complications reported following laparoscopic aneurysm repair include bleeding from the hypogastric artery in <1% (1 out of 122; HALS) and bleeding requiring reoperation in 2% (1 out of 60; TLS).
In three non-randomised controlled trials that compared laparoscopic aneurysm repair with open surgery, the mean operative time was longer in the laparoscopic (181 [HALS], 462 and 468 minutes [TLS]) than in the open surgery groups (136, 300 and 301 minutes, respectively; significance not reported). A fourth non-randomised controlled study comparing HALS with endovascular stenting reported that mean operative time was longer in the HALS group (198 and 149 minutes, respectively; not statistically significant).
In one case series mean operative time was 257 minutes with HALS; in another it was 175 minutes with HALS and 265 minutes with TLS. For more details, see the overview.
Safety outcomes highlighted by the Specialist Advisers were death within 30 days and late mortality, and major complications such as blood loss, infection, and multiple organ failure. They all agreed that the safety of this novel procedure is uncertain and that advanced training in laparoscopic surgical techniques is important.
It was noted that the different laparoscopic techniques have differing technical demands and training requirements. The Committee considered that total cross-clamp time and long-term graft performance are important outcome measures.