Flashback blood collection needle
AssigneeBecton, Dickinson and Company
InventorChee Leong Tan
Life of this patent
Estimating the term…
Abstract
A needle assembly includes a transparent or translucent housing with a fluid inlet end, a fluid outlet end, a flashback chamber and a venting mechanism therebetween. Substantially axially aligned inlet and outlet cannulas extend from the housing and communicate with the chamber. A sealable sleeve covers the external end of the outlet cannula. Relative volumes of the cannulas, the chamber and the sleeve are selected to provide rapid reliable flashback indicative of venous entry with an internal vent plug over the outlet of the flashback chamber to inhibit leakage of blood from the needle on withdrawal from the patient.
Claims18
A needle assembly comprising:
- a housing comprising a housing chamber defining an interior volume, a flashback chamber, and a vent mechanism separating the housing chamber from the flashback chamber;
- a patient cannula end extending from a first end of the housing to the flashback chamber defining a patient cannula volume and a non-patient cannula end extending from a second end of the housing to the flashback chamber defining a non-patient cannula volume, said patient cannula end and non-patient cannula end both in fluid communication with the flashback chamber of the housing;
- and
- a sleeve controlling fluid flow out of said non-patient cannula end,
- wherein a first volume defined by the interior volume of the housing chamber, the flashback chamber, the non-patient cannula end, and the sleeve is at least 25.3 times a second volume defined by the volume of the patient cannula end.
A needle assembly comprising:
- a housing comprising a housing chamber defining an interior volume, a flashback chamber, and a vent mechanism separating the housing chamber from the flashback chamber;
- a first cannula mounted in said housing chamber, said first cannula having a patient end which extends exterior of the housing chamber and an interior end which extends into said flashback chamber;
- and
- a second cannula mounted in said housing chamber, said second cannula having a non-patient end which extends exterior of the housing chamber and an interior end which extends into said flashback chamber, said second cannula mounted in axial alignment with said first cannula;
- wherein said interior end of said first cannula and said interior end of said second cannula are separated by an axial gap having a length of at least 0.5 mm.
A method of flashback visualization for a blood collection needle assembly comprising:
- providing a needle assembly for blood collection, said needle assembly comprising a housing comprising a housing chamber having a wall portion defining a predetermined interior volume, a flashback chamber, a vent mechanism separating the housing chamber from the flashback chamber, a patient cannula end extending from a first end of the housing to the flashback chamber defining a patient cannula volume and a non-patient cannula end extending from a second end of the housing to the flashback chamber defining a non-patient cannula volume, said patient cannula end and non-patient cannula end in fluid communication with the flashback chamber of the housing, and a sleeve mounted about the non-patient cannula end controlling fluid flow out of said non-patient cannula end;
- providing a blood flow into the intravenous end of said cannula and into the chamber through said aperture such that air is pushed out of the cannula into the chamber, through the vent mechanism and into the housing interior;
- and
- continuing the blood flow such that the blood contacts the vent mechanism and seals the vent mechanism against flow of air from said housing interior back into said chamber.
Dependencies are inferred from the claim text.