Prevention of mural thrombus in porous inner tube of double-layered tube by saline perfusion.

An in vitro experiment under laminar nonpulsatile blood flow and an acute canine ex vivo femoral A-V series shunt experiment were undertaken to investigate the effectiveness of saline perfusion through pores of porous tubes to prevent formation of mural thrombus. PS/SBR porous tubes were used for the in vitro experiment. Commercially obtained ePTFE porous tubes were etched by sodium naphthalenide, and the etched tubes were used for the ex vivo experiment. According to the results of the in vitro experiment, mural thrombus on the surface of the porous tube could be prevented by the saline perfusion. Adhered blood cells decreased semi-logarithmically with increased perfusion rate (up to 0.022 ml/min-cm2) of isotonic saline solution. According to results of the ex vivo experiment, mural thrombus decreased with increased perfusion rate (up to 0.060 ml/min-cm2).