摘要 |
A needle assembly includes a transparent or translucent housing with a fluid inlet end, a fluid outlet end and a flashback chamber therebetween. Substantially axially aligned inlet and outlet cannulas extend from the housing and communicate with the chamber. The external end of the outlet cannula is covered by a sealable sleeve. Relative volumes of the cannulas, the chamber and the sleeve are selected to provide rapid reliable flashback indicative of venous entry. |