Patent Application
20080172004
The present invention relates generally to luer activated devices or valves that allow for the bidirectional transfer of fluids to and from medical fluid flow systems.
Luer activated devices (LAD) or valves (LAV) are commonly used in association with medical fluid containers and medical fluid flow systems that are connected to patients or other subjects undergoing diagnostic, therapeutic or other medical procedures. A LAD can be attached to or part of a fluid container or a medical fluid flow system to simplify the addition of fluids to or withdrawal of fluids from the fluid flow system.
Within the medical field there are a wide variety of medical fluid flow systems, serving a variety of functions. One of the more common uses of LADs are in association with fluid flow systems that are used for the intravenous administration of fluids, such as saline, antibiotics, or any number of other medically-related fluids, to a patient. These flow systems are commonly referred to as intravenous or “IV” fluid administration sets, and use plastic tubing to connect a phlebotomized subject to one or more medical fluid sources, such as intravenous solution or medicament containers.
Typically, such intravenous administration sets include one or more LADs providing needless access to the fluid flow path to allow fluid to be added to or withdrawn from the IV tubing. The absence of a needle for injecting or withdrawing fluid has the important advantage of reducing the incidence of needle stick injuries to medical personnel. A LAD typically includes a tapered female luer component, such as the inlet into a valve housing, that accepts and mates with a tapered male luer of a medical infusion or aspiration device, such as a needleless syringe or an administration set tubing brand.
There are certain characteristics and qualities of LADs that are highly desirable. For example, the LAD should provide a sufficient microbial barrier for the full service life of the valve. It is desirable that the microbial barrier be conducive to the application of standard aseptic techniques preformed by clinicians during the use of the device. For example, the geometry of the LAD should be such that it is easily swabbable and reduces the potential of entrapping particulates or contaminants that cannot be cleanly swabbed clear prior to use.
Furthermore, it is highly desirable that the LAD be substantially devoid of any interstitial space or any other “dead space” that cannot be flushed, or that such interstitial space be physically isolated from the fluid flow path. Such interstitial space has the potential of providing an environment for undesired microbial growth. In addition, the LAD should have a geometry that allows it to be sufficiently flushed so as to clear the dynamic fluid path and adjacent areas of residual blood or intravenous fluids to prevent undesired clotting or microbial growth.
LAD's are commonly used with intravenous catheters that provide access to a patient's vascular system. In such systems, another desirable feature of a LAD is minimal displacement of fluid during insertion and removal of the male luer. In certain situations, it is preferable that the LAD be a neutral/neutral device in that there is zero or only a very slight displacement of fluid during both insertion and removal of the male luer. In other situations it can be desirable for the LAD to produce a positive displacement of fluid from the valve housing during the insertion and removal of the male luer. The LAD also preferably prevents blood reflux into the catheter. Reflux is known to reduce the efficiency of the catheter and contribute to catheter clotting.
In most situations it is preferred that the LAD be ergonomically dimensioned to be completely activated by a wide range of ISO compliant male luer lock adaptors. However, there may some instances when the LAD is specifically designed to be activated by a male luer lock that is not ISO complaint. Another desirable characteristic of a LAD is the ability of the LAD to seal against pressure contained within a fluid system to which the LAD is connected. For example, it is desirable to be leak resistance to positive pressures ranging from 10 to 45 psi and to negative pressures or vacuum from 1 to 5 psi. The LAD also preferably has a geometry that allows for easy priming and flushing that does not require any additional manipulations to remove residual air bubbles from the tubing system.
These and other desirable characteristics, which may be used separately or in combination, is preferably present over the full service life of the valve. When used in connection with an IV set or catheter, the LAD may go through many connections and disconnections. It is desirable that the life of an LAD last through upwards to about 100 connections and disconnections or 96 hours of dwell time.
As described more fully below, the fluid access devices of the present invention provides important advances in the safe and efficient administration or withdrawal of medical fluids to or from a fluid flow system.
In accordance with one aspect of the present invention, a medical valve is provided with a valve housing having an inlet adapted for receiving a male luer, an outlet and a flow path therethrough. The medical valve also includes a stretchable membrane that seals the flow path of the valve housing. The stretchable membrane includes at least one resealable opening having a normally closed configuration preventing the flow of fluid through the medical valve and an open configuration that allows the flow of fluid through the medical valve. The resealable opening changes from the closed configuration to the open configuration upon stretching of the stretchable membrane. When a male luer is inserted into the opening of the valve inlet, the male luer stretches the stretchable membrane without passing therethrough, thereby changing the resealable opening from the normally closed position to the open position.
According to another aspect of the present invention, a medical valve is provided with a valve housing inlet adapted for receiving a male luer, an outlet and a flow path therethrough. The medical valve also includes a valve member associated with the inlet and having a stretchable membrane including at least one resealable aperture. The resealable aperture has a normally closed configuration for preventing fluid flow and an open configuration that allows fluid flow. The resealable aperture opens upon stretching of the stretchable membrane by a male luer inserted into the housing. The male luer stretches the stretchable membrane without passing therethrough.
According to yet another aspect of the present invention, a method of transferring fluid from a male luer to a medical valve. The method comprises inserting a male luer into an opening of an inlet of a medical valve that is sealed by a stretchable member including at least one resealable opening. The resealable opening is closed when the stretchable member is in a relaxed state and opened when the stretchable member is stretched. The method further includes stretching the stretchable member by insertion of a male luer to open the resealable opening without passing therethrough and transferring fluid through the male luer and medical valve.
In describing the preferred embodiments of the present invention, reference will be made to the accompanying drawings, wherein:
It is to be understood that the present invention disclosed herein, may be embodied in various forms. Therefore, specific details described herein are not to be interpreted as limiting the present invention.
One embodiment of a luer activated device (LAD) of the present invention is shown generally in
Inlet 18 can be made to conform with ISO and ANSI standards to receive a male luer also conforming with ISO and ANSI standards. In the embodiment shown in
Similarly, outlet 20 is preferably made to conform with international standards or can be specially designed to connect to any number fluid flow systems. Typically, outlet 20 can be connected to IV administrative tubing sets. To allow LAD 10 to be secured to an IV administration set, the bottom portion 16 can include threads 25 on an interior wall of skirt 28.
In accordance with the present invention, the LAD can include a valve to control fluid introduction or withdrawal therethrough. More particularly, as illustrated in
Valve member 30 is preferably made of latex or any suitable polymeric elastomer, such as silicone or similar material. The valve member 30 may be attached to the housing to seal inlet 18 in any suitable manner. For example, the valve member 30 may be bonded to the housing by adhesive or mechanically attached in any well known manner. The valve member 30 is preferably mounted to provide a smooth, flat surface at the inlet for ease of swabbing with a disinfecting agent, such as alcohol. For receiving a male luer, such as luer 32, the valve member 30 preferably has an aperture in the form of a slit 34, although the shape of the aperture is not critical.
Downstream or distal of the first valve member 30, the LAD 10 includes a second valve 36. As illustrated in
In use, upon insertion of a male luer 32 into the LAD 10, the luer first passes through slit 35 of the microbial barrier valve member 30 and immediately engages valve member 36. Further insertion of male luer 32 into the LAD causes the second valve member to extend and stretch, conforming generally around the male luer. This stretching also causes the slit 38 to open for introduction or withdrawal of fluid through the LAD 10. Because the second valve element 36 is stretched around and substantially covering the male luer 32, the external surface of the male luer 37 is substantially prevented from coming into contact with the internal fluid path through the valve housing or the internal wall 39 of the valve housing. This arrangement reduces the chances of cross-contamination between the male luer and the internal wall 39 of the housing.
The combination of the first and second valve members offers several benefits. The second valve member is resistant to significant back pressure when in the normally closed position (
An alternative LAD 40 is shown in
A further difference is evident in
