Towards an ideal polyurethane graft for hemodialysis

Numerous studies have been reported in the field of vascular graft in recent years. The main interest in these studies has focused on producing either a small diameter arterial graft or prosthesis for veins. Polyurethane polymers are emerging because of their superior mechanical, chemically stable and biocompatible nature. Above all, the prominent blood compatibility and elasticity has attracted many investigators to investigate the material for vascular grafts with small diameter. Although several difficulties still remain to be solved, important factors such as anti-thrombogenicity of materials, compliance in long term, porosity, surface microstructure, and permeability are discussed on the basis of many experimental results. In addition, our basic as well as clinical examination of polyurethane graft as a blood access for hemodialysis are presented along with future prospects and difficulties to overcome.