Vorrichtung zur Blutentnahme

摘要

A blood withdrawal apparatus provided which a blunt cannula or needle (58) is adapted to penetrate an elastomeric septum (40) into a pressurized flow channel (26), such as an arterial line. After blood has been sucked into the attached syringe (60), the needle tip (78) is partially withdrawn from the septum (40) until an indication is detected, for example by engagement of a detent (90) on a shroud (80) surrounding the cannula or needle (58), with a detent (54) on the housing (34) for the septum (40). The nurse can then depressurize the syringe (60) by operating the piston (70) and thus prevent blood-spurt when the needle tip (78) is subsequently fully withdrawn from the septum (40).