A porcine model for endolaparoscopic abdominal aortic repair and endoscopic training.

OBJECTIVES

The goals of this laboratory model were to evaluate the performance of the surgical team and endolaparoscopic techniques in the porcine model of infrarenal abdominal aortic repair.

METHODS

Twenty-four pigs underwent full endolaparoscopic aorto-aortic graft implantation with voice-activated computerized robotics. The first group of 10 pigs (acute) was sacrificed while under anesthesia at 0.5 hours (5 animals) and 2 hours (5 animals). The second group of 14 pigs (survival) were recovered from anesthesia and maintained for 7 hours (5 pigs) and 7 days (9 pigs) prior to sacrifice. Survival animals were observed for evidence of hind limb dysfunction. All grafts were visually inspected at autopsy.

RESULTS

All animals survived the operation. All grafts were successfully implanted, and all were patent with intact anastomoses at autopsy. Mean aortic clamp time for each group was as follows: acute, 92.9 +/- 28.04 minutes; survival, 59.6 +/- 13.8 minutes; P=0.0008. Total operative time for each group was as follows: acute, 179 +/- 39.6 minutes; survival, 164.6 +/- 48 minutes; P=0.44 ns. Estimated blood loss for each group was as follows: acute, 214 -/+ 437.8 mL; survival 169.2 +/- 271 mL; P=0.76 ns. from respiratory arrest; 1 animal suffered motor sensory dysfunction of the hind limbs (spinal cord ischemia); significant bleeding occurred in 6 of 24 pigs; 8 of the 9 seven-day survivors required minimal pain medication and had normal hind limb function.

CONCLUSIONS

The reduction in aortic clamp time, total operative time, and blood loss as the study progressed indicate the feasibility of this surgical protocol and the maturation of the learning process, which is paramount in prevention of 2 main sources of morbidity: bleeding and spinal cord ischemia. The reduction in aortic clamp time between the acute and survival groups was dramatic and statistically significant. An intensive formal training program combining dry and live surgical laboratories is deemed essential for the development of endoscopic skill sets necessary for this challenging procedure.