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.
Claims16
A needle assembly comprising:
- a housing comprising
- (a) a housing interior,
- (b) a chamber in communication with the housing interior,
- (c) a first cannula mounted in the housing in communication with the chamber, and a second cannula mounted in the housing in communication with the chamber, or a single cannula mounted in the housing with an opening in communication with the chamber, wherein the sole communication path between the housing interior and the external environment is via the chamber;
- a vent mechanism located in the communication path between said chamber and said housing;
- wherein upon contact with blood, said venting mechanism seals against the flow of air from the housing interior into the chamber.
A method of flashback visualization for a blood collection needle assembly comprising the steps;
- a) providing a needle assembly for blood collection, said needle assembly comprising a housing comprising a housing interior, a chamber in communication with the housing interior, a first inlet cannula mounted in the housing in communication with the chamber, and a second outlet cannula mounted in the housing in communication with the chamber, wherein the sole communication path between the housing interior and the external environment is via the chamber, and a vent mechanism located in the communication path between said chamber and said housing;
- wherein upon contact with blood, said venting mechanism seals against the flow of air from the housing interior into the chamber.
- b) providing a blood flow into the first inlet cannula and into the chamber such that air is pushed out of the cannula into the chamber, through the vent mechanism and into the housing interior;
- and
- c) continuing the blood flow such that the blood contacts the vent mechanism, thereby sealing the vent mechanism against flow of air from said housing interior back into said chamber or out to the surrounding atmosphere.
A needle assembly comprising:
- a housing comprising
- (d) a housing interior,
- (e) a chamber in communication with the housing interior,
- (f) a first cannula mounted in the housing in communication with the chamber, and a second cannula mounted in the housing in communication with the chamber, or a single cannula mounted in the housing with an opening in communication with the chamber,
- wherein the sole communication path between the housing interior and the external environment is via the chamber;
- a vent mechanism located in the communication path between said chamber and said housing;
- a sealable sleeve mounted over portions of said second cannula disposed externally of the outlet end of said housing;
- wherein said sealable sleeve, said lumen of said second outlet cannula and said chamber of said housing and said housing define a combined volume which is greater than a volume defined by said lumen of said first cannula.
- wherein upon contact with blood, said venting mechanism seals against the flow of air from the housing interior into the chamber.
Dependencies are inferred from the claim text.