Low-dose syringes containing air vent systems

Abstract

A medical device is described that can fill a syringe barrel with a liquid while evacuating air from the syringe. An exemplary medical device includes a syringe barrel with a tapered sidewall portion to allow air to be evacuated from the chamber and prevent liquid from exiting the chamber, a plunger rod, and a stopper. Another exemplary medical device includes a syringe barrel with multiple vent grooves associated with the barrel's sidewall, a plunger rod, and a stopper. Also described is a medical device that includes a syringe barrel, a plunger rod, and a stopper with a porous plug. A medical device is described that includes a syringe barrel with multiple vent grooves associated with the barrel's sidewall and a porous membrane, a plunger rod, and a stopper disposed over the vent grooves. A method of filling a syringe barrel with a liquid is also provided.

Description

[Technical Field]

[0001] Aspects of the present disclosure relate to a medical device that can evacuate air trapped within the medical device while filling the medical device with a liquid. [Background technology]

[0002] Syringe barrels contain, store, transport, and measure fluids, typically medications or other liquids for delivery to patients. Medical devices, such as plunger rods and stoppers, are used to aspirate and expel fluids from syringe barrels. During aspiration, air can become trapped within the syringe barrel. The presence of air in the syringe barrel can lead to inaccurate dose measurements and other problems.

[0003] Typically, air is removed from a syringe barrel by inverting the syringe barrel, forcing the trapped air into the opening through which the fluid is drawn. The air is then expelled from the opening by applying a distal force to the plunger rod. However, this expulsion process may expel some of the liquid drawn into the syringe barrel. Additionally, this method of removing air from a syringe barrel may require the user to agitate the syringe barrel to move air bubbles toward the opening.

[0004] To reduce preparation time and improve clinician efficiency, there is a need to provide a device to facilitate removal of air trapped in the barrel during dose preparation. Summary of the Invention [Means for solving the problem]

[0005] Some embodiments of medical devices are provided that include a structure for evacuating air from a syringe barrel when filling the syringe barrel with a liquid. Exemplary syringe barrels described herein include a sidewall having an inner surface defining a chamber for holding a fluid, an open proximal end, and a distal end including a distal wall extending distally with a tip having an open passageway in fluid communication with the chamber. The medical device includes a plunger rod and a stopper disposed within the chamber of the syringe barrel or other container.

[0006] A first aspect of the present disclosure relates to a medical device including a syringe barrel having an open proximal end, a distal end, and a distal wall. The sidewall extends from the distal end to the open proximal end and includes an inner surface defining a chamber for retaining or holding a fluid, which may include a liquid medication and / or other liquid. A tip extending distally from the distal wall. The tip having an open passageway therethrough in fluid communication with the chamber.

[0007] The medical device also includes a plunger rod having a proximal end, a distal end, and a body extending from the proximal end to the distal end, the plunger rod being disposed within the chamber and movable proximally and distally within the chamber.

[0008] The medical device also includes a stopper having a distal face and a proximal end, the stopper being attached to the plunger rod, the stopper being disposed within the chamber and being movable proximally and distally within the chamber.

[0009] The syringe barrel sidewall includes a first sidewall portion and a second sidewall portion. The first sidewall portion is disposed at the distal end of the barrel. The first sidewall portion has an inner diameter equal to or less than the outer diameter of the stopper, forming a releasable fluid-tight seal between the stopper and the inner surface of the barrel sidewall. The second sidewall portion is disposed at the open proximal end of the barrel. The second sidewall portion includes a taper. The second sidewall portion has an inner diameter larger than the outer diameter of the stopper, forming a gap between the inner surface of the sidewall and the stopper, preventing liquid from exiting the chamber while breaking the releasable seal between the stopper and the barrel sidewall, thereby allowing air to be expelled from the chamber. In one or more embodiments, the inner diameter of the second sidewall portion gradually increases proximally.

[0010] In one or more embodiments, the distal end of the plunger rod is disposed within the barrel and the stopper forms a releasable seal with a sidewall of the barrel having an inner diameter equal to or less than the outer diameter of the stopper, and when the stopper reaches a taper in the second sidewall portion at the open proximal end of the barrel, the releasable fluid-tight seal between the stopper and the inner surface of the sidewall of the barrel is broken.

[0011] In one or more embodiments, distal movement of the plunger rod against the taper of the second sidewall portion at the open proximal end of the barrel reforms the releasable seal, allowing fluid within the chamber to be expelled through an open passage in the tip that is in fluid communication with the chamber.

[0012] In one or more embodiments, the medical device includes a barrel graduation mark. In one or more embodiments, the second sidewall portion is proximal to the barrel graduation mark.

[0013] Another aspect of the present disclosure relates to a method for filling a syringe barrel with a liquid, comprising providing a medical device as described herein. The tip of the syringe barrel is submerged in the liquid and an air source, and the liquid is drawn into the chamber before reaching the tapered sidewall of the barrel. When the stopper reaches the gap formed by the second sidewall portion, allowing air to escape from the chamber and preventing liquid from exiting the chamber, the plunger rod is moved proximally beyond the second sidewall portion of the barrel, allowing the stopper to break a releasable fluid-tight seal between the stopper and the inner surface of the barrel sidewall, thereby venting the air source from the chamber. When the stopper contacts the first sidewall portion, the releasable fluid-tight seal is reformed, allowing fluid in the chamber to be expelled through an open passage in the tip that is in fluid communication with the chamber.

[0014] Another aspect of the present disclosure relates to a medical device including a syringe barrel including a sidewall having an inner surface defining a chamber for holding a liquid, an open proximal end, and a distal end including a distal wall having an open passageway in fluid communication with the chamber and a distally extending tip. The sidewall includes a first sidewall portion and a second sidewall portion. The medical device also includes a plunger rod having a proximal end, a distal end, and a body extending from the proximal end to the distal end. The plunger rod is disposed within the chamber and is movable proximally and distally within the chamber. The medical device includes a stopper disposed within the chamber. The stopper includes a distal face and a proximal end. The stopper is movable proximally and distally within the chamber. The distal end of the barrel includes a first sidewall portion for forming a releasable fluid-tight seal between the stopper and the inner surface of the first sidewall portion of the barrel. In one or more embodiments, the open proximal end of the barrel includes a second sidewall portion having a vent groove embedded therein, allowing air to escape from the chamber and breaking a releasable seal between the stopper and the barrel sidewall to prevent liquid from exiting the chamber. In one or more embodiments, the open proximal end of the barrel includes a second sidewall portion having a plurality of vent grooves embedded therein, allowing air to escape from the chamber and breaking a releasable seal between the stopper and the barrel sidewall to prevent liquid from exiting the chamber.

[0015] The stopper forms a releasable fluid-tight seal with the first sidewall portion of the barrel when the distal end of the plunger rod is disposed within the first sidewall portion.

[0016] When the distal end of the plunger rod is disposed within the second sidewall portion, the stopper breaks a releasable fluid-tight seal between the stopper and the first sidewall portion of the barrel.

[0017] As the plunger rod moves distally from the second sidewall portion toward the first sidewall portion, the stopper contacts the first sidewall portion, reforming a releasable fluid-tight seal and discharging fluid within the chamber through an open passageway at the tip that is in fluid communication with the chamber.

[0018] Another aspect of the present disclosure relates to a method for filling a syringe barrel with a liquid, comprising providing a medical device as described herein. The tip of the syringe barrel is submerged in a liquid and an air source, and the liquid is drawn into the chamber before reaching a plurality of vent grooves embedded in the second sidewall portion of the barrel. Moving the plunger rod proximally expels the air source from the chamber through the plurality of vent grooves embedded in the second sidewall portion of the barrel, allowing air to exit the chamber and breaking a releasable fluid-tight seal between the stopper and the inner surface of the first sidewall portion of the barrel to prevent liquid from exiting the chamber. When the stopper contacts the first sidewall portion, the releasable fluid-tight seal is reformed, allowing fluid in the chamber to be expelled through an open passage in the tip that is in fluid communication with the chamber.

[0019] Another aspect of the present disclosure relates to a medical device including a syringe barrel including a sidewall having an inner surface defining a chamber for holding a liquid, an open proximal end, and a distal end including a distal wall having an open passageway in fluid communication with the chamber and having a distally extending tip. The sidewall includes a first sidewall portion and a second sidewall portion. A plunger rod including a proximal end, a distal end, and a body extending from the proximal end to the distal end. The plunger rod is disposed within the chamber and is movable proximally and distally within the chamber. A stopper is disposed within the chamber and is movable proximally and distally within the chamber, the stopper including a distal surface and a proximal end.

[0020] The distal end of the barrel includes a first sidewall portion for forming a releasable fluid-tight seal between the stopper and the inner surface of the first sidewall portion of the barrel, and the open proximal end of the barrel includes a second sidewall portion including a plurality of vent grooves embedded within the inner surface of the second sidewall portion of the barrel to break the releasable seal between the stopper and the sidewall of the barrel.

[0021] A porous membrane is disposed over the plurality of vent channels to allow air to flow out of the chamber and prevent liquid from exiting the chamber.

[0022] In one or more embodiments, when the distal end of the plunger rod is positioned within the first sidewall portion, the stopper forms a releasable fluid-tight seal with the first sidewall portion of the barrel. When the distal end of the plunger rod moves over a porous membrane disposed over the plurality of vent grooves in the second sidewall portion, the stopper breaks the releasable fluid-tight seal between the stopper and the first sidewall portion of the barrel. When the plunger rod is moved distally from the second sidewall portion toward the first sidewall portion, the stopper reforms the releasable fluid-tight seal when it contacts the first sidewall portion, allowing fluid within the chamber to be expelled through an open passageway in the tip that is in fluid communication with the chamber.

[0023] In one or more embodiments, the porous membrane disposed over the plurality of vent channels extends in a direction substantially parallel to the longitudinal axis of the chamber. In one or more embodiments, the porous membrane disposed over the plurality of vent channels is disposed along a portion of the second sidewall portion. In one or more embodiments, the porous membrane disposed over the plurality of vent channels is disposed along the entire length of the second sidewall portion.

[0024] Another aspect of the present disclosure provides a medical device as described herein, relating to a method for filling a syringe barrel with a liquid, comprising submerging a tip of the syringe barrel in the liquid. An air source and liquid are drawn into a chamber before reaching a vent groove or grooves embedded in a second sidewall portion of the barrel. Moving a plunger rod proximally expels the air source from the chamber through a porous membrane disposed on the vent grooves embedded in the second sidewall portion of the barrel, allowing air to exit the chamber and a stopper to break a releasable fluid-tight seal between the stopper and the inner surface of the first sidewall portion of the barrel to prevent liquid from exiting the chamber. When the stopper contacts the first sidewall portion, the releasable fluid-tight seal is reformed, allowing fluid in the chamber to exit through an open passage in the tip that is in fluid communication with the chamber.

[0025] Another aspect of the present disclosure relates to a medical device including a syringe barrel including a sidewall with an inner surface defining a chamber for holding a liquid, an open proximal end, and a distal end including a distal wall with an open passageway in fluid communication with the chamber and a distally extending tip. The medical device includes a plunger rod having a proximal end, a distal end, and a body extending from the proximal end to the distal end. The plunger rod is disposed within the chamber and is movable proximally and distally within the chamber. The medical device also includes a stopper disposed within the chamber and is movable proximally and distally within the chamber. The stopper forms a fluid-tight seal with the inner surface of the syringe barrel. The stopper includes an opening, a proximal end, and a distal face having a channel extending from the distal face to the proximal end. A porous plug is disposed within the channel of the stopper to allow air to flow from the chamber and prevent liquid from exiting the chamber.

[0026] In one or more embodiments, the porous plug includes a selective barrier that defines a liquid infiltration pressure and an air infiltration pressure that is less than the liquid infiltration pressure, hi one or more embodiments, the selective barrier includes one of a hydrophobic filter, a swellable polymer, or a combination thereof.

[0027] In one or more embodiments, the plunger rod includes a channel disposed in the body of the plunger rod that extends from the proximal end of the plunger rod to the distal end of the plunger rod, the channel in the plunger rod being in fluid communication with the channel in the stopper.

[0028] In one or more embodiments, the medical device includes a removable plunger cap inserted into a channel in the proximal end of the plunger rod. [Brief explanation of the drawings]

[0029] [Figure 1] FIG. 1 shows a cross-sectional side view of a medical instrument having a barrel with a tapered sidewall, the instrument including a plunger rod and a stopper according to a first embodiment of the present disclosure. [Figure 2] FIG. 2 shows a side view of the stopper and plunger rod of the medical device shown in FIG. [Figure 3] FIG. 3 shows a cross-sectional side view of a medical instrument having a barrel, a plunger rod, and a stopper according to a second embodiment of the present disclosure. [Figure 4] FIG. 4 shows a side view of the stopper and plunger rod of the medical device shown in FIG. [Figure 5A] FIG. 5A shows a cross-sectional side view of the side wall of the medical device shown in FIG. 3 having square shaped vent grooves. [Figure 5B] FIG. 5B shows a cross-sectional side view of the side wall of the medical device shown in FIG. 3 having triangular vent grooves. [Figure 5C] FIG. 5C shows a cross-sectional side view of the side wall of the medical device shown in FIG. 3 having rounded vent grooves. [Figure 6]FIG. 6 shows a cross-sectional side view of a medical instrument having a barrel, a plunger rod, and a stopper according to a third embodiment of the present disclosure. [Figure 7] FIG. 7 shows a side view of the stopper and plunger rod of the medical device shown in FIG. [Figure 8A] FIG. 8A shows a cross-sectional side view of the sidewall of the medical device shown in FIG. 6 having an air vent groove overlaid with a hydrophobic porous membrane air filter. [Figure 8B] FIG. 8B shows a cross-sectional side view of the sidewall of the medical device shown in FIG. 6 having an air vent groove overlaid with a hydrophobic porous membrane air filter. [Figure 9A] FIG. 9A shows a cross-sectional side view of the side wall of the medical device shown in FIG. 8 having square shaped vent grooves. [Figure 9B] FIG. 9B shows a cross-sectional side view of the sidewall of the medical device shown in FIG. 8 having triangular vent grooves. [Figure 9C] FIG. 9C shows a cross-sectional side view of the side wall of the medical device shown in FIG. 8 having rounded vent grooves. [Figure 10] FIG. 10 shows a cross-sectional side view of a medical instrument having a barrel, a plunger rod, and a stopper according to a fourth embodiment of the present disclosure. [Figure 11] FIG. 11 shows a side view of the stopper and plunger rod of the medical device shown in FIG. [Figure 12] FIG. 12 shows a cross-sectional side view of the stopper of the medical device shown in FIGS. [Figure 13] FIG. 13 shows a cross-sectional side view of an alternative embodiment of the stopper and plunger rod of the medical device shown in FIGS. DETAILED DESCRIPTION OF THE INVENTION

[0030] Before describing some exemplary embodiments of the present disclosure, it should be understood that the present disclosure is not limited to the details of construction or process steps set forth in the following description. The present disclosure is capable of other embodiments and of being practiced or carried out in various ways. It should be understood that the constructions shown in Figures 1-13 are merely exemplary, and that components may differ in shape and size from those shown.

[0031] The following definitions are provided for terms used in this disclosure.

[0032] In this disclosure, the convention is followed that the distal end of the device is the end closest to the patient and the proximal end of the device is the end away from the patient and closest to the practitioner.

[0033] As used herein, the use of "a," "an," and "the" includes the singular and plural.

[0034] As used herein, the use of "plurality" includes the singular and the plural.

[0035] Embodiments of the present disclosure described herein, with particular reference to various aspects, provide a medical device including a syringe barrel or other container for drawing a liquid from a source into the syringe barrel. Because syringes have a nozzle that is not contacted by the plunger stopper, air is drawn into the syringe barrel when a liquid, such as a medication, is drawn into the syringe barrel in preparation for injection. The air becomes trapped between the liquid and the stopper. To set the proper injection volume, the trapped air must be purged from the syringe. However, purging the trapped air from the syringe is very difficult, particularly for low-dose syringes such as 1 ml oral, enteral, and / or hypodermic syringes. The present disclosure relates to low-dose syringes with means for expelling air trapped in the barrel during dose preparation. The medical devices described herein generally include a plunger rod and a stopper that allow for the removal or expulsion of air from a liquid drawn into the syringe barrel or other container. In addition to syringe barrels, embodiments of the medical device can be used with other types of containers, such as needleless IV sets or other devices having chambers that can be used to store and / or transport liquid medications and / or other liquids. The syringe barrels described herein may include an optional needle hub, an integral needle cannula, and / or a needle shield.

[0036] 1-2 illustrate one or more embodiments of a medical device 100 according to a first aspect of the present disclosure. As shown in FIGS. 1-2, the medical device 100 includes a syringe barrel 110 having open proximal and distal ends 112, 114, and a distal wall 116. A sidewall 118 extends from the distal end 114 to the open proximal end 112 and includes an inner surface 120 defining a chamber 122 for retaining or holding a fluid, which may include a liquid medication and / or other liquid. A tip 124 extends distally from the distal wall 116. The tip 124 has an open passageway 126 therethrough in fluid communication with the chamber 122. The syringe barrel 110 may include a finger flange 128 at the open proximal end 112 extending radially outward from the sidewall 118. A needle hub may be utilized to attach a needle cannula to the tip 124. The needle hub may include a needle cannula with a lumen or opening therethrough and may be attached to the tip 124 such that the lumen is in fluid communication with the open passageway 126 and chamber 122. The needle hub may include distal and proximal ends and a body defining a hollow space. When assembled, the tip 124 is inserted through the open proximal end of the needle hub and into the hollow space until the body frictionally engages the tip 124. Alternatively, the needle cannula may be attached to the tip 124 without a needle hub using other methods known in the art. The inner surface 120 of the syringe barrel 110 may have a smooth surface without protrusions or depressions. During use, the plunger rod 130 and stopper 140 are inserted into the open proximal end 112 of the syringe barrel 110.

[0037] As shown more clearly in FIG. 2 , the plunger rod 130 has a proximal end 132, a distal end 136, and a body 134 extending from the proximal end 132 to the distal end 136. The plunger rod 130 is disposed within the chamber 122 and is movable proximally and distally within the chamber 122. The plunger rod 130 may be made of a hard plastic or other material. Examples of such materials include polypropylene, polyethylene, polycarbonate, and combinations thereof. The proximal end 132 of the plunger rod 130 includes a thumb press 138. The distal end 136 of the plunger rod 130 includes a stopper-engaging portion. According to one or more embodiments of the present invention, the stopper-engaging portion is shaped to fit within a stopper cavity of a stopper 140 and retain the stopper 140 at the distal end 136 of the plunger rod. In certain embodiments, the plunger rod 130 and the stopper 140 may be integrally formed or permanently attached.

[0038] 2, stopper 140 has a distal end 142 and a proximal end 144. Stopper 140 includes an outer surface and an inner surface that define a stopper cavity. Stopper 140 can be formed from an elastomeric material, a polymeric material, or other materials known in the art.

[0039] 1-2, medical device 100 includes a plunger rod 130 attached to a stopper 140. Stopper 140 is disposed within chamber 122 and is movable proximally and distally within chamber 122.

[0040] The sidewall 118 of the syringe barrel 110 includes a first sidewall portion 118A and a second sidewall portion 118B. The first sidewall portion 118A is disposed at the distal end 114 of the barrel 110. The first sidewall portion 118A has an inner diameter equal to or less than the outer diameter of the stopper 140 to form a releasable fluid-tight seal between the stopper 140 and the inner surface 120 of the sidewall 118 of the barrel 110. The second sidewall portion 118B is disposed at the open proximal end 112 of the barrel 110. The second sidewall portion 118B includes a taper that defines an air purge zone 119. Second sidewall portion 118B has an inner diameter that is larger than the outer diameter of stopper 140, forming a gap 150 between the inner surface 120 of sidewall 118 and stopper 140, creating a releasable seal between stopper 140 and sidewall 118 of barrel 110, thereby preventing liquid from exiting chamber 122 while allowing air to escape from chamber 122. In one or more embodiments, the inner diameter of second sidewall portion 118B gradually increases in the proximal direction. The inner diameter of barrel 110 gradually increases in the proximal direction such that gap 150 exists between barrel 110 and stopper 140 when stopper 140 is pulled to this position. When instrument 100 is held in a position over tip 124, gravity acting on the liquid in chamber 122 quickly and easily forces any trapped air out.

[0041] By forming a seal between stopper 140 and first sidewall portion 118A of barrel 110, a vacuum is created between the distal face of stopper 140 and chamber 122 of syringe barrel 110, allowing liquid to be aspirated into chamber 122. The configuration of stopper 140 and barrel sidewall 118 prevents the seal from being released during aspiration and when liquid is being expelled from chamber 122 of syringe barrel 110, but allows stopper 140 to close the proximal end of the barrel after a desired amount of liquid has been drawn in and the stopper reaches the tapered portion of second sidewall portion 118B of syringe barrel 110, allowing air within barrel chamber 122 to be expelled.

[0042] In one or more embodiments, the distal end of the plunger rod is disposed within the barrel, and the stopper forms a releasable seal with a sidewall of the barrel, the sidewall having an inner diameter equal to or less than the outer diameter of the stopper. When the stopper 140 reaches the taper of the second sidewall portion 118B of the open proximal end 112 of the barrel 110, the releasable fluid-tight seal between the stopper 140 and the inner surface 120 of the sidewall 118 of the barrel 110 is broken.

[0043] In one or more embodiments, when the plunger rod 130 is moved distally against the taper of the second sidewall portion 118B at the open proximal end 112 of the barrel 110, a releasable seal is reformed, allowing fluid within the chamber 122 to be expelled through an open passage 126 in the tip 124 that is in fluid communication with the chamber 122.

[0044] In one or more embodiments, medical device 100 includes barrel graduation marks 160. In one or more embodiments, second sidewall portion 118B is proximal to the barrel graduation marks.

[0045] Another aspect of the present disclosure relates to a method for filling a syringe barrel 110 with a liquid, comprising providing a medical device 100 as described herein, submerging a tip 124 of a syringe barrel 110 in a liquid, drawing an air source 170 and the liquid into a chamber 122, and, when a stopper 140 reaches a taper of a second sidewall portion 118B at an open proximal end 112 of the barrel 110, evacuating the air source 170 from the chamber 122 by moving a plunger rod 130 proximally to break a releasable liquid-tight seal between the stopper 140 and the inner surface 120 of the sidewall 118 of the barrel 110. The gravity of the liquid acting on the air source 170 trapped within the chamber 122 is a driving force for expelling the air source 170 from the chamber 122.

[0046] 3-5 illustrate one or more embodiments of a medical device 200 according to another aspect of the present disclosure. As more clearly shown in FIG. 3 , the medical device 200 includes a syringe barrel 210 having open proximal and distal ends 212, 214, and a distal wall 216. A sidewall 218 extends from the distal end 214 to the open proximal end 212 and includes an inner surface 220 defining a chamber 222 for retaining or holding a fluid, which may include a liquid medication and / or other liquid. A tip 224 extends distally from the distal wall 216. The tip 224 has an open passageway 226 therethrough in fluid communication with the chamber 222. The syringe barrel 210 may include a finger flange 229 at the open proximal end 212 extending radially outward from the sidewall 218. A needle hub may be utilized to attach a needle cannula to the tip 224. The needle hub may include a needle cannula with a lumen or opening therethrough and may be attached to the tip 224 such that the lumen is in fluid communication with the open passageway 226 and the chamber 222. The needle hub may include distal and proximal ends and a body defining a hollow space. When assembled, the tip 224 is inserted through the open proximal end of the needle hub and into the hollow space until the body frictionally engages the tip 224. Alternatively, the needle cannula may be attached to the tip 224 without a needle hub using other methods known in the art. The inner surface 220 of the syringe barrel 210 may have a smooth surface without protrusions or depressions. During use, the plunger rod 230 and stopper 240 are inserted into the open proximal end 212 of the syringe barrel 210.

[0047] 3-4 , plunger rod 230 has a proximal end 232, a distal end 236, and a body 234 extending from proximal end 232 to distal end 236. Plunger rod 230 is disposed within chamber 222 and is movable proximally and distally within chamber 222.

[0048] 4, stopper 240 has a distal face 242 and a proximal end 244. Stopper 240 includes an outer surface and an inner surface that define a stopper cavity. Stopper 240 can be formed from an elastomeric material, a polymeric material, or other materials known in the art.

[0049] 3-4, medical device 200 includes a plunger rod 230 attached to a stopper 240. Stopper 240 is disposed within chamber 222 and is movable proximally and distally within chamber 222.

[0050] The sidewall 218 of the syringe barrel 210 includes a first sidewall portion 218A and a second sidewall portion 218B. The first sidewall portion 218A is disposed at the distal end 214 of the syringe barrel 210 and forms a releasable fluid-tight seal between the stopper 240 and the inner surface 220 of the sidewall 218 of the syringe barrel 210. The second sidewall portion 218B is disposed at the open proximal end 212 of the syringe barrel 210. In one or more embodiments, the open proximal end of the barrel includes the second sidewall portion 218B having a vent groove embedded within the second sidewall portion of the barrel, allowing air to escape from the chamber and breaking the releasable seal between the stopper and the barrel sidewall to prevent liquid from exiting the chamber. In one or more embodiments, second sidewall portion 218B includes a plurality of vent grooves 280 embedded within the inner surface of second sidewall portion 218B of syringe barrel 210, allowing air to escape from chamber 222 and breaching the releasable seal between stopper 240 and first sidewall portion 218A of syringe barrel 210 to prevent liquid from exiting chamber 222. The width of vent groove 280 is selected to allow air to escape and prevent liquid from leaking. The width of vent groove 280 may range from 0.025 mm to 1 mm. In certain embodiments, the width of vent groove 280 may range from 0.05 mm to 0.5 mm. In one or more embodiments, the width of vent groove 280 may gradually increase in the proximal direction. In one or more embodiments, the plurality of vent grooves 280 are disposed along a portion or the entire length of the inner surface of second sidewall portion 218B of syringe barrel 210, which defines air purge zone 219. In one or more embodiments, a plurality of vent grooves 280 can be molded into the inner diameter of the syringe barrel 210. When the stopper 240 is over the plurality of vent grooves 280, air is expelled under the gravitational load of the liquid in the chamber 222. The plurality of vent grooves 280 can be sized to allow air to escape through the plurality of vent grooves 280 while preventing liquid from escaping due to surface tension. In one or more embodiments, the plurality of vent grooves 280 extend along the second sidewall portion in a direction substantially parallel to the longitudinal axis "L" of the chamber.In one or more embodiments, the plurality of vent grooves 280 may have any desired shape, including, but not limited to, a triangular, square, rectangular, or rounded shape, as shown in Figures 5A-5C. In one or more embodiments, the plurality of vent grooves 280 may be tapered. In one or more embodiments, the plurality of vent grooves 280 may be equidistantly spaced around the circumference of the inner surface of the chamber 222. In one or more embodiments, the plurality of vent grooves 280 may be oriented in opposite directions from one another around the circumference of the chamber 222.

[0051] In one or more embodiments, the multiple ventilation grooves 280 can be arranged in one or more individual groove sets. The individual grooves comprising the multiple ventilation grooves 280 can be positioned adjacent to one another. In alternative embodiments, the individual grooves comprising the multiple ventilation grooves 280 can be spaced apart from one another. In another embodiment, the multiple ventilation grooves 280 can be oriented 180° apart around the circumference of the inner surface of the cavity.

[0052] When the medical device 200 is held in position on the tip 224, gravity acting on the liquid within the chamber 222 quickly and easily forces any trapped air out.

[0053] In one or more embodiments, when distal end 236 of plunger rod 230 is disposed within first sidewall portion 218A, stopper 240 forms a releasable fluid-tight seal with first sidewall portion 218A of syringe barrel 210. When distal end 236 of plunger rod 230 is disposed within second sidewall portion 218B and stopper 240 reaches a plurality of vent grooves 280 embedded within second sidewall portion 218B at open proximal end 212 of syringe barrel 210, the releasable fluid-tight seal between stopper 240 and inner surface 220 of sidewall 218 of syringe barrel 210 is broken.

[0054] In one or more embodiments, as the plunger rod 230 moves distally from the second sidewall portion 218B toward the first sidewall portion 218A against the multiple ventilation grooves 280 in the second sidewall portion 218B at the open proximal end 212, the releasable seal of the syringe barrel 210 is reformed when the stopper 240 contacts the first sidewall portion, allowing fluid in the chamber 222 to be expelled through the open passage 226 in the tip 224, which is in fluid communication with the chamber 222.

[0055] In one or more embodiments, medical device 200 includes barrel graduation marks 260. In one or more embodiments, second sidewall portion 218B is proximal to barrel graduation marks 260.

[0056] Another aspect of the present disclosure includes providing a medical device 200 as described herein, submerging a tip 224 of a syringe barrel 210 in a liquid, drawing an air source 270 and the liquid into chamber 222 before reaching a plurality of vent grooves 280 embedded in second sidewall portion 218B, and moving plunger rod 230 proximally beyond the plurality of vent grooves 280 embedded in second sidewall portion 218B of syringe barrel 210 to vent air source 270 from chamber 222, causing stopper 240 to move at open proximal end 212 of syringe barrel 210 until it reaches the plurality of vent grooves 280 in second sidewall portion 218B. and when stopper 240 contacts first sidewall portion 218A, it reforms the releasable liquid-tight seal, allowing fluid within chamber 222 to be expelled through open passageway 226 in tip 224 that is in fluid communication with said chamber 222. Gravity of the liquid acting on air source 270 trapped within chamber 222 is the driving force for expelling air source 270 from chamber 222.

[0057] 6-9C illustrate one or more embodiments of a medical device 300 according to another aspect of the present disclosure. As more clearly shown in FIGS. 6-7 , the medical device 300 includes a syringe barrel 310 having open proximal and distal ends 312, 314, and a distal wall 316. A sidewall 318 extends from the distal end 314 to the open proximal end 312 and includes an inner surface 320 defining a chamber 322 for retaining or holding a fluid, which may include a liquid medication and / or other liquid. A tip 324 extends distally from the distal wall 316. The tip 324 has an open passageway 326 therethrough in fluid communication with the chamber 322. The syringe barrel 310 may include a finger flange 328 at the open proximal end 312 extending radially outward from the sidewall 318. A needle hub may be utilized to attach a needle cannula to the tip 324. The needle hub may include a needle cannula with a lumen or opening therethrough and may be attached to the tip 324 such that the lumen is in fluid communication with the open passageway 326 and the chamber 322. The needle hub may include distal and proximal ends and a body defining a hollow space. When assembled, the tip 324 is inserted through the open proximal end of the needle hub and into the hollow space until the body frictionally engages the tip 324. Alternatively, the needle cannula may be attached to the tip 324 without a needle hub using other methods known in the art. The inner surface 320 of the syringe barrel 310 may have a smooth surface without protrusions or depressions. During use, the plunger rod 330 and stopper 340 are inserted into the open proximal end 312 of the syringe barrel 310.

[0058] 6-7, plunger rod 330 has a proximal end 332, a distal end 336, and a body 334 extending from proximal end 332 to distal end 336. Plunger rod 330 is disposed within chamber 322 and is movable proximally and distally within chamber 322.

[0059] 7, stopper 340 has a distal face 342 and a proximal end 344. Stopper 340 includes an outer surface and an inner surface that define a stopper cavity. Stopper 340 can be formed from an elastomeric material, a polymeric material, or other materials known in the art.

[0060] 6-7, medical device 300 includes a plunger rod 330 attached to a stopper 340. Stopper 340 is disposed within chamber 322 and is movable proximally and distally within chamber 322.

[0061] 6-8B, the sidewall 318 of the syringe barrel 310 includes a first sidewall portion 318A and a second sidewall portion 318B. The first sidewall portion 318A is disposed at the distal end 314 of the syringe barrel 310 and forms a releasable fluid-tight seal between the stopper 340 and the inner surface 320 of the sidewall 318 of the syringe barrel 310. The second sidewall portion 318B is disposed at the open proximal end 312 of the barrel 310. In one or more embodiments, the open proximal end of the barrel includes the second sidewall portion 318B having a vent groove 380 embedded within the second sidewall portion of the barrel, allowing air to escape from the chamber and breaking the releasable seal between the stopper and the barrel sidewall to prevent liquid from exiting the chamber. In one or more embodiments, as shown more clearly in FIGS. 8A-9C , second sidewall portion 318B of syringe barrel 310 includes a plurality of vent grooves 380 embedded within its interior surface. These vent grooves 380 breach a releasable seal between stopper 340 and first sidewall portion 318A of syringe barrel 310 to allow air to escape from chamber 322 and prevent liquid from exiting chamber 322. The width of vent grooves 380 may range from 0.025 mm to 2.0 mm. In one or more embodiments, the width of vent grooves 380 may gradually increase in the proximal direction. As shown more clearly in FIGS. 8A-9C , a hydrophobic porous membrane air filter 390 covers the plurality of vent grooves 380 embedded within the interior surface of second sidewall portion 318B of syringe barrel 310, facilitating purging of trapped air while preventing liquid leakage.

[0062] In one or more embodiments, a plurality of vent grooves 380 with hydrophobic porous membrane air filters 390 thereon are disposed along a portion or the entire length of the inner surface of second sidewall portion 318B of syringe barrel 310. In one or more embodiments, the plurality of vent grooves 280 can be molded into the inner diameter of syringe barrel 210. When stopper 340 is positioned over the plurality of vent grooves 380 covered with hydrophobic porous membrane air filters 390, air is expelled under the gravitational load of the liquid in chamber 322. Hydrophobic porous membrane air filters 390 can be sized to allow air to leak through them while preventing liquid from leaking out due to surface tension. The plurality of vent grooves 380 can be sized to allow air to leak through them while preventing liquid from leaking out due to surface tension. In one or more embodiments, the plurality of vent grooves 380 covered with hydrophobic porous membrane air filters 390 extend along the second sidewall portion in a direction substantially parallel to the longitudinal axis "L" of the chamber. In one or more embodiments, the plurality of vent grooves 380 may have any desired shape, including, but not limited to, triangular, square, rectangular, or rounded shapes, as shown in FIGS. 9A-9C . In one or more embodiments, the plurality of vent grooves 380 covered with hydrophobic porous membrane air filters 390 may be spaced equidistantly around the circumference of the inner surface of the chamber 322. In one or more embodiments, the plurality of vent grooves 380 covered with hydrophobic porous membrane air filters 390 may be oriented in opposite directions from one another around the circumference of the chamber 322.

[0063] In one or more embodiments, the multiple vent grooves 380 covered with the hydrophobic porous membrane air filter 390 may be arranged in one or more individual groove sets. The individual grooves comprising the multiple vent grooves 380 may be positioned closely together. In alternative embodiments, the individual grooves comprising the multiple vent grooves 380 may be spaced apart from one another. In another embodiment, the multiple vent grooves 380 may be oriented 180° apart around the circumference of the inner surface of the cavity.

[0064] When the medical device 300 is held in a tip 324 upward position, gravity acting on the liquid in the chamber 322 quickly and easily pushes trapped air out of a plurality of vent channels 380 covered with a hydrophobic porous membrane air filter 390.

[0065] In one or more embodiments, when the distal end 336 of the plunger rod 330 is positioned within the first sidewall portion 318A, the stopper 340 forms a releasable fluid-tight seal with the first sidewall portion 318A of the barrel 310. When the distal end 336 of the plunger rod 330 is positioned within the second sidewall portion 318B and the stopper 340 reaches a porous membrane air filter 390 covering a plurality of vent channels 380 embedded within the second sidewall portion 318B at the open proximal end 312 of the syringe barrel 310, the releasable fluid-tight seal between the stopper 340 and the inner surface 320 of the sidewall 318 of the syringe barrel 310 is broken.

[0066] In one or more embodiments, when the plunger rod 330 moves distally from the second sidewall portion 318B toward the first sidewall portion 318A against the multiple vent grooves 280 in the second sidewall portion 218B at the open proximal end 212 of the syringe barrel 310, the releasable seal is reformed when the stopper 340 contacts the first sidewall portion, allowing fluid in the chamber 322 to be expelled through the open passage 326 in the tip 324, which is in fluid communication with the chamber 322.

[0067] In one or more embodiments, medical device 300 includes a barrel graduation 360. In one or more embodiments, a hydrophobic porous membrane air filter 390 covering second sidewall portion 318B is proximal to barrel graduation 360.

[0068] Another aspect of the present disclosure relates to a method for filling a syringe barrel 310 with a liquid, comprising providing a medical device 300 as described herein. The tip 324 of the syringe barrel 310 is submerged in the liquid. An air source 370 and the liquid are drawn into a chamber 322 before reaching a hydrophobic porous membrane air filter 390 that covers a plurality of vent grooves 380 embedded in a second sidewall portion 318B of the syringe barrel 310. Air source 370 is evacuated from chamber 322 by moving plunger rod 330 proximally over hydrophobic porous membrane air filter 390 located on a plurality of vent grooves 380 embedded in second sidewall portion 318B of syringe barrel 310, allowing air to be evacuated from chamber 322 when stopper 340 reaches hydrophobic porous membrane air filter 390 located on a plurality of vent grooves 380 in second sidewall portion 318B at open proximal end 312 of syringe barrel 310, thereby breaking the releasable liquid-tight seal between stopper 340 and inner surface 320 of first sidewall portion 318A of syringe barrel 310 to prevent liquid from exiting chamber 322. Gravity of the liquid acting on air source 370 trapped within chamber 322 is the driving force for expelling air source 370 from chamber 322.

[0069] When the stopper 340 contacts the first sidewall portion 318A, a releasable fluid-tight seal is reformed, allowing fluid within the chamber 322 to be expelled through the open passage 326 in the tip 324 that is in fluid communication with said chamber 322.

[0070] 10-13 show one of the more alternative embodiments of a medical device 400 according to another aspect of the present disclosure, which incorporates a hydrophobic porous membrane air filter into the stopper to allow air to escape from the trapped space, but not the liquid inside. The advantage of this approach is that it allows for more efficient dose preparation, as the stopper does not need to be pulled back into the air purge zone.

[0071] As shown more clearly in FIG. 10 , the medical device 400 includes a syringe barrel 410 having open proximal and distal ends 412 and 414 and a distal wall 416. A sidewall 418 extends from the distal end 414 to the open proximal end 412 and includes an inner surface 420 defining a chamber 422 for retaining or holding a fluid, which may include a liquid medication and / or other liquid. A tip 424 extends distally from the distal wall 416. The tip 424 has an open passageway 426 therethrough in fluid communication with the chamber 422. The syringe barrel 410 may include a finger flange 429 at the open proximal end 412 that extends radially outward from the sidewall 418. A needle hub may be utilized to attach a needle cannula to the tip 424. The needle hub may include a needle cannula with a lumen or opening therethrough and may be attached to the tip 424 such that the lumen is in fluid communication with the open passageway 426 and the chamber 422. The needle hub may include distal and proximal ends and a body defining a hollow space. When assembled, the tip 424 is inserted through the open proximal end of the needle hub and into the hollow space until the body frictionally engages the tip 424. Alternatively, the needle cannula may be attached to the tip 424 without a needle hub using other methods known in the art. The inner surface 420 of the syringe barrel 410 may have a smooth surface without protrusions or depressions. During use, the plunger rod 430 and stopper 440 are inserted into the open proximal end 412 of the syringe barrel 410.

[0072] 10-11 , plunger rod 430 has a proximal end 432, a distal end 436, and a body 434 extending from proximal end 432 to distal end 436. Plunger rod 430 is disposed within chamber 422 and is movable proximally and distally within chamber 422. As shown more clearly in FIG. 10 , medical device 400 includes plunger rod 430 attached to stopper 440. Stopper 440 is disposed within chamber 422 and is movable proximally and distally within chamber 422.

[0073] As shown more clearly in FIG. 12 , stopper 440 has a distal end 441 with a distal surface 442 and a proximal end 444. Stopper 440 is disposed within chamber 422 and is movable proximally and distally within chamber 422, such that stopper 440 forms a fluid-tight seal with the inner surface of syringe barrel 410. Stopper 440 includes an outer surface and an inner surface defining a channel 445 within the body extending from distal end 441 to proximal end 444 for venting air. Distal surface 442 has an opening 447 in fluid communication with channel 445. Channel 445 within the stopper has a depth, shape, or cross-sectional width that allows air within the barrel to escape through channel 445. A porous plug 449 is disposed within channel 445 of stopper 440 to allow air to flow from chamber 422 while preventing liquid from exiting chamber 422.

[0074] The porous plug 449 of the medical device embodiments described herein may include a selective barrier that defines a liquid penetration pressure and an air penetration pressure that is lower than the liquid penetration pressure. In one or more embodiments, the porous plug 449 may include a hydrophilic filter, a hydrophobic filter, a swellable polymer, and / or other suitable materials that are air permeable and liquid impermeable, and / or combinations thereof. Examples of suitable hydrophilic filters include hydrophilic polytetrafluoroethylene membrane filters. Such filters are available from WL Gore & Associates of Elkton, Maryland. Examples of suitable hydrophobic filters include spunbond olefin, a material known under the trademark "Tyvek" (registered trademark) manufactured by EI duPont de Nemours and Company, Inc. of Wilmington, Delaware, or a material known under the trademark "Acropor" (registered trademark) made of acrylonitrile. Nylon-reinforced polyvinyl chloride is available from Gelman Instrument Company, Ann Arbor, Mich. Other suitable hydrophobic filters include those made from polytetrafluoroethylene, nylon, cellulose nitrate, cellulose acetate, and Paulsar sulfone.

[0075] A suitable hydrophobic filter prevents liquid from passing through the filter under a moderate pressure gradient. In one or more embodiments, the hydrophobic filter has a pressure at which water or air passes through or penetrates the hydrophobic filter that is greater than the water or air penetration pressure. In certain embodiments, the water penetration pressure of the hydrophobic filter is greater than the vacuum pressure generated within the chamber of a syringe barrel or other container and / or within the stopper and plunger rod assembly described herein. This pressure difference creates a pressure difference across the porous portion that drives air and liquid toward the porous portion, and the liquid impermeability of the porous portion prevents liquid from passing through the porous portion and allows air to pass through the porous portion.

[0076] Porous plug 449 may be shaped and positioned to occupy a portion of the distal face of the stopper to provide a vent system for air within the syringe barrel to escape without interfering with the ability of the stopper or plunger rod to form a seal with the syringe barrel. In one or more embodiments, porous plug 449 may be shaped and positioned to occupy an opening in distal face 442 and is in fluid communication with channel 445 of stopper 440. In one or more embodiments, porous plug 449 is air permeable and liquid impermeable. In one or more embodiments, porous plug 449 comprises a selective barrier having a liquid penetration pressure and an air penetration pressure that is less than the liquid penetration pressure.

[0077] In one or more embodiments, the porous plug 449 has a circular shape. Alternatively, the porous plug 449 may have a square and / or rectangular shape. In one or more embodiments, the porous plug 449 may be integrally formed or disposed on the distal surface 442 adjacent the opening 447. In certain embodiments, the porous plug 449 has a cross-sectional width that is less than the cross-sectional width of the distal surface 442. The porous portion may also be integrally formed and / or disposed adjacent the channel 445 on the interior surface of the stopper.

[0078] The porous plug 449 may be integrally formed on the distal surface 442 such that the periphery of the distal surface 442 and the body of the stopper remain non-porous. The porous plug 449 may also be molded to fit within the opening 447. For example, the porous plug 449 can extend from the distal surface 442 into the channel 445. The porous plug 449 may have a periphery molded into a portion of the distal surface 442. In one or more embodiments, the porous plug 449 may be attached to the distal surface 442 of the stopper by mechanical means, such as adhesive and / or molding. In certain embodiments, the distal surface 442 may include a pocket (not shown) for retaining and securing the porous plug 449 adjacent the distal surface 442 and the opening 447 such that the porous plug 449 is in fluid communication with the channel 445.

[0079] In one or more embodiments, a porous plug can be associated with the stopper to allow air to enter the stopper cavity and prevent liquid from entering the stopper cavity.

[0080] 13 , the plunger rod 430 has a channel 438 disposed in the body 434 of the plunger rod 430 extending from the proximal end 432 to the distal end 436 that is in fluid communication with the channel 445 in the stopper. A plunger cap 450 may be removably inserted into the channel 438 at the proximal end 432 of the plunger rod 430. The plunger cap 450 is shaped and positioned to occupy a portion of the channel 438 at the proximal end 432 of the plunger rod 430, providing a vent system for air within the syringe barrel to escape without interfering with the stopper or the plunger rod's ability to form a seal with the syringe barrel. In one or more embodiments, a porous plug 449 may be shaped and positioned to occupy the opening in the distal face 442 and is in fluid communication with the channel 445 in the stopper 440. Plunger cap 450 is inserted into a portion of channel 438 at proximal end 432 of plunger rod 430 during syringe filling and dispensing. Plunger cap 450 is removed from channel 438 at proximal end 432 of plunger rod 430 during evacuation of air from chamber 422. In one or more embodiments, plunger cap 450 can be designed as a push button such that a vent path in channel 438 can be opened or closed by pressing plunger cap 450.

[0081] Plunger cap 450 may be formed from an elastomeric material, a polymeric material, or other material known in the art.

[0082] Stopper 440 may be formed from an elastomeric material, a polymeric material, or other materials known in the art.

[0083] References throughout this specification to "one embodiment," "a particular embodiment," "one or more embodiments," or "an embodiment" mean that the particular features, structures, materials, or features described in connection with the embodiment are included in at least one embodiment of the invention. Thus, the appearances of phrases such as "in one or more embodiments," "in a particular embodiment," "in one embodiment," or "in an embodiment" in various places throughout this specification do not necessarily refer to the same embodiment of the invention. Furthermore, particular features, structures, materials, or features may be combined in any suitable manner in one or more embodiments.

[0084] Although the present disclosure has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present disclosure. It is therefore to be understood that many modifications can be made to the exemplary embodiments and that other arrangements can be devised without departing from the spirit and scope of the present disclosure as disclosed.

Claims

1. a syringe barrel including: a sidewall having an inner surface defining a chamber for holding a liquid, the sidewall including a first sidewall portion and a second sidewall portion; an open proximal end; and a distal end including a distal wall having an open passageway in fluid communication with the chamber and having a tip extending distally from the distal wall; a plunger rod having a proximal end, a distal end, and a body extending from the proximal end to the distal end, the plunger rod being disposed within the chamber and movable proximally and distally within the chamber; a stopper disposed within the chamber and movable proximally and distally within the chamber, the stopper having a distal surface and a proximal end; Equipped with the distal end of the syringe barrel includes a first sidewall portion for forming a releasable fluid-tight seal between the stopper and an inner surface of the first sidewall portion of the syringe barrel, and the open proximal end of the syringe barrel includes a second sidewall portion including a plurality of vent grooves embedded within the inner surface of the second sidewall portion of the syringe barrel; a porous membrane disposed over the plurality of vent channels to allow air to flow out of the chamber and prevent liquid from exiting the chamber; the tip of the syringe barrel is submerged in the liquid; the stopper forms a releasable fluid-tight seal with the first sidewall portion of the barrel when the distal end of the plunger rod is disposed within the first sidewall portion; when the distal end of the plunger rod is moved over the porous membrane disposed over the plurality of vent grooves of the second sidewall portion, the stopper allows only the air to pass through the porous membrane to form the releasable fluid-tight seal between the stopper and the first sidewall portion of the barrel; When the plunger rod is moved distally from the second sidewall portion toward the first sidewall portion, the stopper contacts the first sidewall portion, preventing the passage of air through the porous membrane and reforming the releasable fluid-tight seal, and allowing the liquid in the chamber to be expelled through the open passage in the tip that is in fluid communication with the chamber.

2. The medical device of claim 1 , wherein the porous membrane disposed on the plurality of ventilation grooves extends in a direction substantially parallel to the longitudinal axis of the chamber.

3. The medical device of claim 1 , wherein the porous membrane disposed on the plurality of ventilation grooves is disposed along a portion of the second sidewall portion.

4. The medical device of claim 1 , wherein the porous membrane disposed on the plurality of vent grooves is disposed along the entire length of the second sidewall portion.

5. Providing a medical device according to claim 1; submerging the tip of the syringe barrel in a liquid; drawing an air source and the liquid into the chamber before reaching the plurality of vent grooves embedded within the second sidewall portion of the barrel; venting the air source from the chamber by moving the plunger rod proximally past the porous membrane disposed on the plurality of vent grooves embedded in the second sidewall portion of the barrel to allow the stopper to break the releasable fluid-tight seal between the stopper and the inner surface of the first sidewall portion of the barrel to allow air to be expelled from the chamber and prevent liquid from exiting the chamber; and when the stopper contacts the first sidewall portion, the releasable fluid-tight seal is reformed, allowing the liquid in the chamber to drain through the open passageway in the tip that is in fluid communication with the chamber.

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