Surgery – Means for introducing or removing material from body for... – Treating material introduced into or removed from body...
Reexamination Certificate
2000-02-28
2002-10-08
Esquivel, Denise L. (Department: 3749)
Surgery
Means for introducing or removing material from body for...
Treating material introduced into or removed from body...
C251S349000, C251S354000
Reexamination Certificate
active
06461335
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a device for preventing fluid free flow in a fluid administration system, and more particularly to an anti-free flow valve device disposed within a lumen of a tube assembly. More specifically, the present invention relates to a tube diameter dependent anti-free-flow valve device that prevents fluid free flow when the tube assembly is in a relaxed condition, while permitting uninhibited fluid flow when the tube assembly is in a stretched condition.
2. Prior Art
Administering fluid containing medicine or nutrition to a patient is generally well-known in the art. Typically, fluid is supplied to a patient by a tube assembly which provides a fluid pathway between a fluid source and a patient. The fluid is supplied to the patient through the tube assembly by either an enteral connection which accesses a visceral organ (gastrointestinal feeding) of a patient or through a parenteral connection which accesses a non-visceral organ (intravenous feeding).
Fluid flow rate through the tube assembly may be manually controlled by a mechanical clip which is designed to progressively occlude the tube assembly and selectively impede fluid flow induced by the force of gravity. One such mechanical clip which operates to occlude a portion of the tube assembly is a conventional roller clamp that has a hollow body with opposed outlets and a pair of angled slots formed opposite of one another transverse to the outlets. The clip further includes a wheel having an axle which is coupled to the body through the slots. A portion of the tube assembly is then inserted through both the outlets and the wheel axially advanced along the slots to pinch a portion of the tube against the body which progressively occludes the tube assembly. Although the mechanical clip operates to provide a cost-efficient method for controlling fluid flow rate, the clip must be manually actuated by the user. Further, the wheel of the mechanical clip can be inadvertently bumped or jostled out of position resulting in an inappropriate flow rate.
In order to better enhance fluid flow rate control in a fluid administration system, calibrated pumps have been utilized. One such calibrated pump is a peristaltic pump connected in-line along a portion of the tube assembly between the fluid source and the patient. The peristaltic pump advances the fluid through the tube assembly by progressively occluding successive portions of the tube assembly and urging each occluded portion forward. When a peristaltic pump is utilized to control the fluid flow rate, mechanical clips are typically not employed or are disengaged to prevent the clip from interfering with the operation of the pump.
Although peristaltic pumps have substantially advanced the art, further improvements are required. For example, once the tube assembly is disengaged from the pump fluid flow rate through the tube assembly becomes unrestrained as fluid is drawn through the tube assembly due to the force of gravity. This situation is known as fluid free flow and may present an undesirable, or even life-threatening situation, if left undetected because of the risk of overfeeding or overmedicating a patient.
In order to overcome the above-noted drawbacks to fluid administration systems utilizing pumps, several devices have been suggested which operate to automatically occlude a portion of the tube assembly and prevent fluid free flow when the tube assembly becomes disengaged from the pump while also permitting uninhibited fluid flow when the tube assembly is properly engaged to the pump. For instance, a variety of automatic occluders have been suggested to improve the art such as those disclosed in U.S. Pat. No. 4,689,043 to Bisha entitled “IV Tube Activator” which describes a clamp for use with a peristaltic pump. The clamp includes a V-shaped channel which is spring biased into a closed position where the narrow portion of the V-shaped channel is sized to substantially crimp, or occlude, a portion of the tube assembly and prevent fluid free flow therethrough. The clamp is placed in an open position by a handle which overlays the pump and depresses the springs such that the tube assembly is positioned within the wider portion of the V-shaped channel to permit unrestricted flow through the tube assembly when the pump is operating. When the handle is released, the V-shaped portion will automatically slide into the closed position and prevent fluid free flow by occluding a portion of the tube assembly.
Another automatic occluder is disclosed in U.S. Pat. No. 5,704,582 to Winterer, et al. entitled “Pinched Clipped Occluder for Infusion Sets” which describes a clip that is positioned between a housing and a cover of a pump. The clip has a plunger biased by a spring towards a portion of the tube assembly so that the lumen of the tube assembly becomes occluded by the plunger. Fluid flow through the tube assembly may only be established when the plunger is biased away from the lumen of the tube assembly which occurs when the cover is properly coupled with the housing. However, once the cover becomes disengaged from the housing, the plunger is automatically biased into the closed position by the spring to prevent fluid free flow.
Although both of the aforementioned automatic occluders have advanced the art, both devices are mechanically complex and prone to mechanical failure. In addition, the mechanical complexity of these devices also results in occluders which are expensive to manufacture. Accordingly, there is a need in the art for a simple valve device that is capable of preventing fluid free flow when the tube assembly is disengaged from the pump, while permitting uninhibited fluid free flow when the tube assembly is disengaged from the pump.
OBJECTS AND SUMMARY OF THE INVENTION
In brief summary, the present invention overcomes and substantially alleviates the deficiencies present in the art by providing a valve device for preventing fluid free-flow in a fluid administration system. The valve device of the present invention is disposed within the lumen of a tube assembly for preventing fluid free flow when the tube assembly is disengaged from the pump, while permitting uninhibited fluid flow when the tube assembly is engaged with the pump.
Preferably, the pump of the fluid administration system used in conjunction with the present invention includes a rotor for advancing fluid through the tube assembly and a pair of recesses positioned adjacent the rotor for retaining portions of the tube assembly to the housing of the pump during operation of the system. The tube assembly comprises three interconnected tube segments each having a distal and proximal ends for providing a fluid pathway between the fluid source and a patient. The fluid source is connected to the distal end of the first tube segment, while the proximal end thereof is connected to the distal end of the second tube segment by a drip chamber having an abutment surface. The proximal end of the second tube segment is interconnected to the distal end of the third tube segment by a coupling having an external flange. Finally, the proximal end of the third tube segment is attached to a patient through either an enteral or parenteral connection.
The tube assembly is engaged with the pump by threading a portion of the assembly around the rotor with the abutment surface of the drip chamber and external flange of the coupling engaged within the first and second recesses, respectively, of the pump. Preferably, the second tube segment as it is engaged around the rotor has a length which permits the abutment surface and the external flange to be properly captured by the first and second recesses and place the second tube segment in a stretched condition. Each of the tube segments has a lumen formed therethrough to allow the passage of fluid through the tube assembly. Alternatively, the valve device may be used with a tube assembly not having a drip chamber or coupling.
Preferably, the valve device of the present invention is disposed within the lumen o
Esquivel Denise L.
Greensfelder Hemker & Gale, P.C.
Nguyen Tu C.
Sherwood Services AG
LandOfFree
Tube dependent anti-free-flow valve does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Tube dependent anti-free-flow valve, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Tube dependent anti-free-flow valve will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3000162