Patent Description:
Medical treatments often include the infusion of a medical fluid (e.g., a saline solution or a liquid medication) to patients using an intravenous (IV) catheter that is connected though an arrangement of flexible tubing and fittings, commonly referred to as an "IV set," to a source of fluid, for example, an IV bag. Certain medical fluids may be transported in vials or other vessels other than an IV bag. Medical fluids transported in vials or other vessels may be retrieved and introduced to the IV set via intermediate syringes.

In some applications, during the use of medical fluids that are transported in vials or other vessels other than an IV bag, simplified medical procedures are desired.

<CIT> discloses a syringe plunger stem with band-like sealing means on one end and fingergrip means on the opposite end and being slidably and sealably insertable into the body of a syringe to variate the volume capacity of the chamber of said syringe. In the plunger there is a capillary action view-tube, positioned in constant sealing contact with the said band-like sealing means and extending longitudinally towards said fingergrip end of said plunger. Further, an air-permeable, liquid impervious porous material is positioned in the said capillary action view-tube that is nearest the said fingergrip end of the plunger. The said capillary action view-tube communicating with and positioned between the said chamber of said syringe and the said air-permeable, liquid impervious porous material. The present invention may also provide a secondary chamber area in the plunger. <CIT> discloses a single-use system for separating blood and producing platelet concentrates, the system includes an elongated container for receiving blood from a patient. The container has a movable plunger mounted within the blood container for expressing blood fractions separated during centrifugation of the container through a first port mounted at one end of said container, a second port mounted on the plunger, and a third port mounted on a plunger rod attached to the plunger.

The disclosed subject matter relates to vented syringes. In certain embodiments, a vented syringe is disclosed that comprises a syringe body defining a syringe cavity; a plunger body disposed at least partially within the syringe cavity, the plunger body comprising an air intake channel defined within the plunger body and extending between a first end and a second end of the plunger body; a plunger seal disposed at the second end of the plunger body and sealingly engaged with the syringe cavity to cooperatively define a syringe volume within the syringe cavity; and a one-way valve in fluid communication with the air intake channel and the syringe volume, wherein the one-way valve is configured to prevent fluid flow from the syringe volume to the air intake channel and permit fluid flow from the air intake channel to the syringe volume.

In certain embodiments, a vented syringe is disclosed that comprises a syringe body defining a syringe cavity; a plunger body disposed at least partially within the syringe cavity, the plunger body comprising an air intake channel defined within the plunger body and extending between a first end and a second end of the plunger body; a plunger seal disposed at the second end of the plunger body and sealingly engaged with the syringe cavity to cooperatively define a syringe volume within the syringe cavity, wherein expansion of the syringe volume provides a vacuum within the syringe volume; and a one-way valve in fluid communication with the air intake channel and the syringe volume, wherein the one-way valve is configured to prevent fluid flow into the air intake channel during expansion of the syringe volume and permit fluid flow from the air intake channel to the syringe volume to release the vacuum within the syringe volume.

In certain embodiments, a method for introducing a medical fluid is disclosed that comprises expanding a syringe volume to introduce the medical fluid via an aperture in fluid communication with the syringe volume; and sealing an air intake channel from the syringe volume during the expansion of the syringe volume.

The disclosed vented syringe incorporates an air intake channel with a one-way valve. The air intake channel can be disposed within the plunger body to permit IV delivery of a medical fluid directly from the vented syringe. By delivering medical fluids directly from the vented syringe, IV sets can be simplified and reduced, and costs can be reduced. Further, the vented syringe can be utilized for plunger delivery of medical fluids, if desired.

The detailed description set forth below is intended as a description of various configurations of the subject technology and is not intended to represent the only configurations in which the subject technology may be practiced. Like components are labeled with identical element numbers for ease of understanding. Reference numbers may have letter suffixes appended to indicate separate instances of a common element while being referred to generically by the same number without a suffix letter.

While the following description is directed to the administration of medical fluid to a patient by a medical practitioner using the disclosed vented syringe, it is to be understood that this description is only an example of usage and does not limit the scope of the claims. Various aspects of the disclosed vented syringe may be used in any application where it is desirable to provide for the direct administration of medical fluids from a vented syringe while permitting the plunger delivery of medical fluids as needed.

The disclosed vented syringe overcomes several challenges discovered with respect to certain conventional syringes. One challenge with certain conventional syringes is that medical fluids cannot be administered via IV delivery with certain conventional syringes without intermediate steps or components. Because the use of additional steps and/or components adds complexity, the use of conventional syringes with IV delivery is undesirable.

Therefore, in accordance with the present disclosure, it is advantageous to provide a vented syringe as described herein that eliminates or substantially reduces intermediate steps or components needed for administration of medical fluids. The disclosed vented syringe provides an air intake channel that permits direct IV administration of medical fluids from the vented syringe while still permitting plunger delivery of medical fluids.

An example of a vented syringe that permits direct IV administration of medical fluids is now described.

<FIG> is a perspective view of a syringe <NUM>, in accordance with various aspects of the present disclosure. In the depicted example, the vented syringe <NUM> can dispense medical fluids by either actuating the plunger body <NUM> relative to the syringe body <NUM> or by functioning as an IV drip.

As illustrated, the plunger body <NUM> is slidable relative to the syringe body <NUM>. In some embodiments, the syringe body <NUM> can be keyed to the features of the plunger body <NUM> to prevent or limit rotational movement of the plunger body <NUM> relative to the syringe body <NUM>. In some embodiments, the plunger body <NUM> can be retracted relative to the syringe body <NUM> to draw in a medical fluid via the aperture or connector <NUM>. Optionally, the connector <NUM> can be any suitable medical connector including a Luer connector. In some embodiments, a pressure differential or vacuum within the syringe body <NUM> relative to the atmosphere maintains drawn medical fluid within the vented syringe <NUM>.

In some applications, to expel or otherwise dispense the medical fluid within the syringe <NUM>, the plunger body <NUM> can be depressed relative to the syringe body <NUM>. The plunger body <NUM> can slide or otherwise travel within the syringe body <NUM> to administer the medical fluid via the connector <NUM>.

In some embodiments, the plunger body <NUM> includes a thumb pad <NUM> at an end of the plunger body <NUM> to allow for ergonomic operation of the vented syringe <NUM>. Further, the syringe body <NUM> can include syringe body extensions <NUM> to allow the clinician to move the plunger body <NUM> relative to the syringe body <NUM> both during a drawing motion of the plunger body <NUM> and the contraction motion of the plunger body <NUM>.

In some applications, after a medical fluid is drawn into the vented syringe <NUM>, the vented syringe <NUM> can be configured to dispense the medical fluid as an IV drip or otherwise dispense the medical fluid without actuating the plunger body <NUM> relative to the syringe body <NUM>.

In the depicted example, a cap <NUM> disposed at the end of the plunger body <NUM> can be removed to expose the medical fluid within the syringe body <NUM> to atmospheric pressure. By exposing the medical fluid within the syringe body <NUM> to atmospheric pressure, any pressure differential or vacuum within the syringe body <NUM> relative to the atmosphere can be equalized or overcome, permitting an IV drip or flow of medical fluid through the connector <NUM>.

Advantageously, by operating the vented syringe <NUM> with cap <NUM> in a closed position, the vented syringe <NUM> can be utilized to administer medical fluids by actuating the plunger body <NUM> relative to the syringe body <NUM>. Further, by removing the cap <NUM> from the plunger body <NUM>, the vented syringe <NUM> can be utilized to administer medical fluids via an IV drip. In some embodiments, the cap <NUM> is disposed within or forms a portion of the thumb pad <NUM>. Optionally, the cap <NUM> can be press fit into the plunger body <NUM>.

<FIG> is a cross-sectional view of the syringe <NUM> of <FIG>, in accordance with various aspects of the present disclosure. As illustrated, <FIG> illustrates the vented syringe <NUM> in an assembled position. <FIG> is a cross-sectional view of a syringe <NUM> in a drawing configuration, in accordance with various aspects of the present disclosure. With reference to <FIG> and <FIG>, the vented syringe <NUM> can be utilized to draw medical fluid <NUM> into the syringe cavity <NUM> within the syringe body <NUM>.

In some applications, to draw fluid into the vented syringe <NUM>, the plunger body <NUM> is retracted relative to the syringe body <NUM>. By retracting the plunger body <NUM>, the plunger seal <NUM> coupled at an end of the plunger body <NUM> moves within the syringe cavity <NUM> of the syringe body <NUM> to expand a syringe volume <NUM>. In some embodiments, the plunger seal <NUM> is in sealing engagement with the inner walls of the syringe cavity <NUM> to cooperatively define the syringe volume <NUM> within the syringe cavity <NUM>. The plunger seal <NUM> can be an expandable and/or elastomeric seal. During the drawing process, by retracting the plunger body <NUM> and the plunger seal <NUM>, the syringe volume <NUM> expands.

As the syringe volume <NUM> expands, the syringe volume <NUM> experiences a negative pressure differential or a vacuum therein. Due to the pressure differential in the syringe volume <NUM> compared to the connector <NUM>, medical fluid <NUM> from the connector <NUM> is drawn into the syringe volume <NUM>. Medical fluid <NUM> can be drawn in via the connector from a vial or any other suitable container. In some applications, the vented syringe <NUM> can be prefilled with medical fluid <NUM>.

During the fluid drawing process, a one-way valve <NUM> can prevent medical fluid <NUM> from entering the air intake channel <NUM> and contacting the filter <NUM>. As illustrated, the air intake channel <NUM> extends from one end of the plunger body <NUM>, adjacent to the plunger seal <NUM> to an opposite end of the plunger body <NUM>, adjacent to the thumb pad <NUM>.

While the air intake channel <NUM> can facilitate air flow or pressure equalization to the syringe volume <NUM> when IV drip functionality is desired, fluid flow of medical fluid <NUM> into the air intake channel <NUM> may not be desired. In some applications, it is desired to prevent or stop medical fluid <NUM> from entering the air intake channel <NUM> to prevent contamination or clogging of the filter <NUM>, contamination of the medical fluid <NUM>, and/or to prevent the migration of medical fluid <NUM> out of the vented syringe <NUM>.

In the depicted example, the one-way valve <NUM> can prevent medical fluid <NUM> from being drawn from the syringe volume <NUM> to the air intake channel <NUM>. During operation, the one-way valve <NUM> can close or collapse to prevent flow into the air intake channel <NUM> as the plunger seal <NUM> is retracted within the syringe body <NUM>. In some embodiments, the one-way valve <NUM> can be a duckbill valve that prevents backflow from the syringe volume <NUM> into the air intake channel <NUM>. Optionally, the one-way valve <NUM> can be integrally formed with the plunger seal <NUM>.

After the drawing process, the pressure differential from the syringe volume <NUM> to the connector <NUM> allows the medical fluid <NUM> to remain in the syringe volume <NUM>. As illustrated, the cap <NUM> can prevent airflow from entering the air intake channel <NUM> and equalizing the pressure differential in the syringe volume <NUM> until desired.

<FIG> are cross-sectional views of a syringe <NUM> in a venting configuration, in accordance with various aspects of the present disclosure. As illustrated in <FIG>, the vented syringe <NUM> can permit the IV administration of the medical fluid retained or stored in the syringe volume <NUM>.

During operation, the cap <NUM> is removed from an end of the air intake channel <NUM> to allow air flow and/or atmospheric pressure to be received by the air intake channel <NUM>. As shown, the cap <NUM> can be removed from the thumb pad <NUM> of the plunger body <NUM>. The cap <NUM> can be releasably engaged with a receptacle <NUM> formed in the thumb pad <NUM>. Optionally, the cap <NUM> can be retained by a tether <NUM> when the cap <NUM> is disengaged from the air intake channel <NUM>.

Upon removal of the cap <NUM>, the air intake channel <NUM> can permit fluid communication between the atmosphere surrounding the vented syringe <NUM> and the syringe volume <NUM> containing the medical fluid <NUM>. Atmospheric pressure introduced via the air intake channel <NUM> can equalize the pressure or otherwise release the vacuum within the syringe volume <NUM>, permitting the medical fluid <NUM> to exit or drip through the connector <NUM>. In some embodiments, the vented syringe <NUM> can be coupled to an infusion pump or positioned above a patient to allow flow to the patient. As shown in <FIG>, flow can continue until all of the medical fluid <NUM> is administered.

In some embodiments, the air intake channel <NUM> is integrally formed with the plunger body <NUM>. Optionally, the air intake channel <NUM> can be formed separately from the plunger body <NUM>. The air intake channel <NUM> can have a generally circular cross-sectional profile. Optionally, the air intake channel <NUM> can have a cross-sectional profile that varies.

In some embodiments, air flow introduced to the syringe volume <NUM> can pass through the one-way valve <NUM>. The one-way valve <NUM> can be configured to allow airflow from the atmosphere, through the air intake channel <NUM> and into the syringe volume <NUM>. In some embodiments, the one-way valve <NUM> is a duckbill valve that can allow flow through the flattened portion of the valve.

The air intake channel <NUM> includes a filter <NUM> to filter the air flow passing through the air intake channel <NUM>. The filter <NUM> can be any suitable filter that allows air flow therethrough while preventing contaminants from entering the medical fluid <NUM>.

Terms such as "top," "bottom," "front," "rear" and the like if used in this disclosure should be understood as referring to an arbitrary frame of reference, rather than to the ordinary gravitational frame of reference. Thus, a top surface, a bottom surface, a front surface, and a rear surface may extend upwardly, downwardly, diagonally, or horizontally in a gravitational frame of reference.

Claim 1:
A vented syringe (<NUM>), comprising:
a syringe body (<NUM>) defining a syringe cavity (<NUM>);
a plunger body (<NUM>) disposed at least partially within the syringe cavity, the plunger body comprising an air intake channel (<NUM>) defined within the plunger body and extending between a first end and a second end of the plunger body, wherein the plunger body further comprises a thumb pad (<NUM>) disposed at the first end of the plunger body;
a filter (<NUM>) included in the air intake channel and disposed inwardly adjacent to the thumb pad at the first end of the plunger body and in fluid communication with the air intake channel;
a plunger seal (<NUM>) disposed at the second end of the plunger body and sealingly engaged with the syringe cavity to cooperatively define a syringe volume (<NUM>) within the syringe cavity; and
a one-way valve (<NUM>) in fluid communication with the air intake channel and the syringe volume, wherein the one-way valve is configured to prevent fluid flow from the syringe volume to the air intake channel and permit fluid flow from the air intake channel to the syringe volume, wherein the one-way valve is disposed at the second end of the plunger body.