Flashback Blood Collection Needle With Segmented Venting
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Solution Overview
Problem
Current venipuncture devices lack immediate indication of successful vein entry, leading to repetitive procedures and increased patient discomfort and costs due to the delay in confirming vein entry through the traditional flashback method.
Innovation Solution
A needle assembly with a clear or translucent housing and an internal vent mechanism that allows blood to flow directly into a flashback chamber for immediate visualization of vein entry, utilizing a porous vent to establish negative pressure and prevent blood leakage upon needle removal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a traditional flashback chamber is used with sufficient dead space, then blood can flow into the chamber for visualization, but there is a delay in confirming vein entry causing repetitive procedures
Solution Approach 1:
The housing interior is segmented into a first chamber (flashback chamber) and a second chamber separated by a porous vent. The first chamber has a smaller volume optimized for immediate blood visualization, while the second chamber handles air venting and negative pressure maintenance. This segmentation allows the flashback function to operate independently with reduced dead space, enabling immediate vein entry confirmation without the time delay caused by traditional larger-volume chambers.
2Reliability
If a porous vent is used to establish negative pressure, then blood leakage is prevented upon needle removal, but the vent mechanism adds device complexity
Solution Approach 1:
A porous vent made of porous material is used to separate the first and second chambers. The porous structure allows air molecules to pass through while maintaining negative pressure differential, preventing blood leakage upon needle removal. The porous material inherently provides both venting and sealing functions without requiring complex mechanical components, thus achieving reliable blood leakage prevention with minimal added complexity.
3Loss of time
If the housing is made clear or translucent for immediate visualization, then vein entry can be confirmed quickly, but manufacturing precision requirements increase
Solution Approach 1:
The housing is made clear or translucent specifically at the first chamber (flashback chamber) to enable immediate blood visualization, while other portions of the housing can be made from standard materials. This localized transparency requirement applies only where blood flow visualization is needed, reducing the overall manufacturing precision burden compared to making the entire housing transparent. The clear housing portion allows phlebotomists to immediately confirm vein entry without waiting for blood to fill a larger chamber.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Provides an immediate visual confirmation of vein entry, reducing unnecessary procedures and costs by ensuring accurate vein entry confirmation and preventing blood leakage, thus enhancing the efficiency and comfort of blood collection.
Implementation Method 1
The porous vent includes pores for passage of air therethrough from the first chamber to the second chamber
Implementation Method 2
The porous vent includes pores for passage of air therethrough from the first chamber to the second chamber, with the porous vent preventing passage of blood therethrough to the second chamber
Implementation Method 3
Upon application of an evacuated container to the non-patient puncture tip, blood is drawn from the first chamber and air is drawn from the second chamber, thereby establishing a negative pressure within the second chamber with respect to an external environment of the needle assembly
Data Source
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AI summary
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 positioned within the housing so as to divide the interior into first and second chambers, with the second chamber being adapted to maintain a negative pressure therein relative to the external environment so as to inhibit leakage of blood from the needle on withdrawal from the patient.