RESUMO
A new venous needle (VN) that also can be used as an arterial needle (AN) has been designed to diminish the undesirable hemodynamic effects of dialysis with high blood flow rate (300-600 ml/min) in arteriovenous polytetrafluoroethylene grafts, and in accesses of short length (U.S. Patent No. 5,662,619). The preferred embodiment has one distal opening, two lateral openings, and two diverters located in the interior surface of the shaft adjacent to each lateral opening. The diverters facilitate the flow of blood to the outside of the needle through the lateral openings. The new VN ejects three jets of blood, contrary to the currently used VN, which ejects one jet of high velocity. This decreases the velocity of the VN flow and the velocity; turbulence; wall shear stress; and positive pressure of the flow, past the VN, during dialysis. These may decrease the endothelial damage, intimal hyperplasia, stenoses, thromboses, and recirculation of dialysis blood (RODB). When used as an AN, the new needle lowers the negative pressure surrounding the AN and the RODB. In summary, the new needle may decrease the complications and prolong the life span of the accesses and improve the performance of dialysis.
