Limited backflow reflux valve
First Claim
1. A limited backflow reflux valve for injecting fluid from a syringe into a patient, comprising:
- a housing,an inlet port in said housing,an outlet port in said housing,a bi-directional port in said housing,a first check valve permitting fluid flow only from said inlet port to said bi-directional port through said housing, anda second check valve permitting fluid flow from said bi-directional port to said outlet port through said housing, and permitting only a predetermined limited volume of fluid to backflow from said outlet port into said limited backflow reflux valve housing, and preventing any further backflow into said limited backflow reflux valve housing from said outlet port beyond said limited volume.
5 Assignments
0 Petitions
Accused Products
Abstract
A limited backflow reflux valve for connection between a syringe, catheter, and bulk container of injection fluid. The reflux valve permits injection of fluid from the syringe through the catheter into the patient, and also permits refilling of the syringe from the bulk container, without disconnection of any tubing. The reflux valve also permits a limited volume of fluid to backflow from the catheter into the syringe, so that the catheter may be checked for patency, but prevents any further backflow along this path after this limited volume. Therefore, the limited backflow reflux valve not only permits injection through the catheter, but also permits both withdrawal of blood from the patient and refilling of the syringe from the bulk contrast media container, without requiring disconnection of the catheter or other tubing and without risk of contamination of the syringe or introduction of air, increasing the efficiency of the injection process, enhancing safety, and reducing waste of injection fluid.
69 Citations
32 Claims
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1. A limited backflow reflux valve for injecting fluid from a syringe into a patient, comprising:
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a housing, an inlet port in said housing, an outlet port in said housing, a bi-directional port in said housing, a first check valve permitting fluid flow only from said inlet port to said bi-directional port through said housing, and a second check valve permitting fluid flow from said bi-directional port to said outlet port through said housing, and permitting only a predetermined limited volume of fluid to backflow from said outlet port into said limited backflow reflux valve housing, and preventing any further backflow into said limited backflow reflux valve housing from said outlet port beyond said limited volume. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
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18. A limited backflow check valve comprising
a housing, an inlet port in said housing, an outlet port in said housing, a sealing element mounted within said housing between said inlet and outlet ports, said sealing element movable in said housing from a first position to a second position within said housing, said sealing element permitting fluid flow from said inlet port to said outlet port through said housing at least when in said first position, said sealing element forming and maintaining a seal preventing fluid flow from said outlet port to said inlet port while said sealing element is in said first position, while said sealing element is in said second position, and while said sealing element is in motion between said first position and said second position, said sealing element displacing a predetermined limited volume of fluid between said first and said second position which can backflow into said outlet port.
Specification