摘要 |
A needle assembly (60) is provided for withdrawing and returning blood and blood components to a patient or other donor, especially in a machine-assisted blood component separating operation, whereby the incidence of clotting and the size of clots formed in the needle is greatly minimized. The needle assembly is especially useful in situations where only low levels of anticoagulant are added to the extracorporeal blood, which, but for the improved needle assembly, would exacerbate the problem of clot formation at the needle. The assembly (60) includes attached tubing (66) having an internal diameter adjacent the blunt end (72) of the needle (68) that is equal to, or preferably less than, the internal diameter of the needle. |