This study evaluated the strength of laser-welded arteriovenous shunts established using St. Jude BioPoly-Meric vascular grafts. The arterial anastomoses of the biological graft were laser welded with and without the addition of soluble collagen or fibrin sealant. In four dogs, 16 arteriovenous grafts were implanted between the femoral artery and vein or the carotid artery and jugular vein using a 6 cm long, 4 mm internal diameter prosthesis. The 16 arterial anastomoses were evenly divided into four groups sutured control, laser welded (LW), LW with soluble collagen applied immediately before and during welding, and LW with fibrin sealant applied after welding. All arterial control and venous anastomoses were sutured using continuous 6-0 polypropylene suture. All LW anastomoses were initially divided into six 5 mm long segments using six evenly spaced 6-0 polypropylene stay sutures. Each segment was laser welded using 15 to 18 5-sec pulses of the 0.5 W (7.5 W/cm2) argon laser energy delivered via a 300 μm fiber while cooling the tissue with slow-drip saline irrigation. Blood flow was established and maintained through each anastomosis for 1 h. The vessels were then controlled, and anastomotic bursting pressure was determined with infusion of heparinized blood. Results: An additional hemostatic suture was required in 3 LW anastomoses (2 LW, 1 LW with collagen). Mean bursting pressures (mm Hg) of the arterial anastomoses were as follows: sutured controls 165 ± 159, LW 144 ± 58, LW and collagen 93 ± 47, LW and fibrin sealant 181 ± 45. There was no statistically significant difference in bursting pressures between any of the anastomotic methods, although there was a trend for decreased strength of fusions formed with collagen applied before LW. This preliminary study suggests that initial laser-welded strength of the bovine heterograft is comparable to sutured controls.
ASJC Scopus subject areas
- Biomedical Engineering