LOW DEAD SPACE NEEDLE

There is provided a needle hub assembly for connecting to a barrel with plunger for assembling a syringe, comprising: a cylindrical depression in a proximal end portion of the needle hub assembly, the cylindrical depression having a flat bottom perpendicular to a longitudinal axis of the needle hub assembly, wherein the cylindrical depression is shaped for connecting to a nozzle of the barrel and for contacting between the flat bottom and a distal end of the nozzle surrounding an opening of the nozzle when the nozzle is disposed within the cylindrical depression, a lumen extending from the flat bottom of the cylindrical depression to a distal end portion of the needle hub assembly, and a cannula having a proximal cannula portion located within the lumen and a distal cannula portion extending distally from the distal end portion of the needle hub assembly.

FIELD AND BACKGROUND OF THE INVENTION

The present invention, in some embodiments thereof, relates to a medical device and, more particularly, but not exclusively, to a low dead space needles.

Syringes are routinely used in medicine to administer an injection such as a vaccine and/or an anesthetic (e.g., to repair a cut, treat a tooth). Syringes may also be used to infuse intravenous therapy, for example, adding a controlled amount of a drug to a saline IV drip. Syringes are commonly disposable, and used in vast quantities on a daily basis.

SUMMARY OF THE INVENTION

According to a first aspect, a needle hub assembly for connecting to a barrel with plunger for assembling a syringe, comprises: a cylindrical depression in a proximal end portion of the needle hub assembly, the cylindrical depression having a flat bottom perpendicular to a longitudinal axis of the needle hub assembly, wherein the cylindrical depression is shaped for connecting to a nozzle of the barrel and for contacting between the flat bottom and a distal end of the nozzle surrounding an opening of the nozzle when the nozzle is disposed within the cylindrical depression, a lumen extending from the flat bottom of the cylindrical depression to a distal end portion of the needle hub assembly, and a cannula having a proximal cannula portion located within the lumen and a distal cannula portion extending distally from the distal end portion of the needle hub assembly.

In a further implementation form of the first aspect, a depth of the cylindrical depression measured parallel to the longitudinal axis is greater than 7 millimeters (mm).

In a further implementation form of the first aspect, an inner surface of the cylindrical depression extending from the flat bottom to a depth120away from an edge of the proximal end portion, is sized and shaped to contact and fluidly seal an exterior surface of the nozzle of the barrel when the barrel is disposed within the cylindrical depression.

In a further implementation form of the first aspect, the inner surface of the cylindrical depression is sized and/or shaped for compliance with ISO 80369-7.

In a further implementation form of the first aspect, the needle hub assembly is sized and/or shaped for compliance with ISO 594-1.

In a further implementation form of the first aspect, the inner surface of the cylindrical depression is set to a 6% Luer tap.

In a further implementation form of the first aspect, further comprising a pair of flares extending outwardly from opposite locations of an external surface of an end of the proximal end portion of the needle hub assembly, wherein a length from an end of a first flare to an end of a second flare perpendicular to the longitudinal axis is about 7.8 millimeters and a diameter of the first end portion excluding the pair of flares is about 6.7 mm.

In a further implementation form of the first aspect, the cylindrical depression is sized and shaped for fitting Luer slip and Luer Lock Tip devices.

In a further implementation form of the first aspect, the cylindrical depression and cannula are sized and shaped to enclose a volume of about 0.0052 milliliters (mL) when a low dead space plunger is fully plunged into the barrel connected to the cylindrical depression.

In a further implementation form of the first aspect, the lumen comprises a proximal lumen portion having a constant internal diameter along a length thereof and a distal lumen portion having a tapered diameter increasing in diameter from a junction with the proximal lumen portion towards an opening at the distal end portion of the needle hub assembly, the proximal lumen portion having an opening into the cylindrical depression.

In a further implementation form of the first aspect, the proximal cannula portion is disposed within the distal lumen portion, wherein at the junction the cannula is in continuity with the distal lumen portion, wherein the cannula has a constant inner diameter along a length thereof matching a constant inner diameter of the distal lumen portion, thereby forming a fluid flowing channel with continuous constant inner diameter for fluid flowing from the barrel via the cylindrical depression via the proximal lumen portion and through the cannula.

In a further implementation form of the first aspect, the cannula is not disposed within the proximal lumen portion.

In a further implementation form of the first aspect, an adhesive is disposed within a space formed between an exterior surface of the proximal cannula portion disposed within the lumen and an interior surface of the tapered distal lumen portion.

In a further implementation form of the first aspect, the adhesive extends externally from the space, forming a cone and/or convex shape having a wider base connected to an end surface of the distal end portion of the needle hub assembly perpendicular to the longitudinal axis, wherein the cannula extends through an interior of the cone and/or convex shape of the extending adhesive.

In a further implementation form of the first aspect, further comprising a support element having a wider base connected to an end surface of the distal end portion of the needle hub assembly perpendicular to the longitudinal axis, wherein the cannula extends through an interior of the support element.

In a further implementation form of the first aspect, the support element comprises an adhesive that supports a portion of the cannula extending past the distal end portion of the needle hub assembly by connecting the cannula extending through the interior of the support element with the end surface of the distal end portion of the needle hub assembly.

In a further implementation form of the first aspect, the cannula is made using medical silicon.

In a further implementation form of the first aspect, the cannula is lubricated by medical silicon fluid.

In a further implementation form of the first aspect, the cannula is made from materials compliant with ISO 9626.

In a further implementation form of the first aspect, a bevel angle of the cannula comprises a triple point.

DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION

The present invention, in some embodiments thereof, relates to a medical devices and, more particularly, but not exclusively, to a low dead space needles.

An aspect of some embodiments of the present invention relates to a needle hub assembly designed to connect to a barrel with plunger for assembling a syringe that has low dead space of remaining fluid therein after the plunger has been fully pushed into the barrel. The needle hub assembly is sized and/or shaped to fit standard barrels and plungers, for example, according to the International Organization for Standardization (ISO). The needle hub assembly includes a cylindrical depression in a proximal end portion thereof. The cylindrical depression has a flat bottom. The flat bottom is arranged perpendicular to a longitudinal axis of the needle hub assembly. The cylindrical depression is sized and/or shaped for contacting an exterior surface of a nozzle of the barrel, optionally according to ISO guidelines. The cylindrical depression is sized and/or shaped to form contact between the flat bottom and a surface in proximity to the opening of the nozzle, and between an interior surface of the cylindrical depression and an exterior surface of the nozzle along a longitudinal axis of the nozzle. The contact between the cylindrical depression and the nozzle is designed to be fluid tight, such that fluid existing from an opening in the nozzle is forced into an opening of a lumen in the flat bottom without having a space for existing between the cylindrical depression and the nozzle. The lumen extends from the flat bottom of the cylindrical depression to a distal end portion of the needle hub assembly. A cannula, for example, a needle, having a proximal cannula portion is located within the lumen. A distal cannula portion of the cannula extends distally from the distal end portion of the needle hub assembly. The amount of fluid remaining in the cannula, the portion of the lumen that that does include the cannula, and a space formed by the nozzle, flat bottom of the cylindrical depression, and interior walls of the cylindrical depression, after the plunger has been fully pressed to inject fluid contents of the barrel, is designed to be low, for example, about 5 microliters, which may be lower than other syringe designs, in particular other syringes assembled from other needle hubs that are compliant with ISO guidelines.

At least some implementations of the needle hub assemble described herein addresses the technical problem of reducing wasted fluid during injections. After performing an injection using a syringe, previously designed needles, such a standard needles, retain a portion of the fluid therein. That is out of a volume of fluid which is loaded into the barrel, the entire volume is not injected. A certain portion of the volume is injected and another portion is retained. Now, when considering the large number of syringes that are used (e.g., on a daily basis), the sum of the retained portions of the vast number of syringes becomes significant. For example, vaccinations, such as for corona virus (i.e., COVID-19), are routinely performed on a large number of people, which may reach millions, or hundreds of millions, or billions of used syringes. Reducing the amount of fluid retained in each syringe may add up to significant savings. The savings may be especially important if the fluid (e.g., vaccine) is in short supply and/or expensive (e.g., botox injections). For example, reducing the amount of fluid retained in each syringe may enable loading6vaccine syringes from a single vial of vaccine (e.g., for corona virus, i.e., COVID-19) in comparison to loading vaccine syringes from the single vial using standard syringes, which enables vaccinating a significantly larger number of people using the same supply of vials.

Reference is now made toFIG.1, which is a schematic to help understand improvement to the technical field of syringes obtained by the needle hub assembly102(e.g., as described with reference toFIG.2) in comparison to other known syringes202A-D, in accordance with some embodiments of the present invention.

Syringe202A is a standard barrel and plunger206A connected to a standard needle hub208A, which retains a very large volume of fluid210A therein, that cannot be injected, and therefore lost.

Syringe202B is a low dead space barrel and plunger206B connected to a standard needle hub208B, which still retains a large volume of fluid210B therein, although it may be less than volume of fluid210A retained by syringe202A.

Syringe202C is a standard barrel and plunger206C connected to a needle hub208C designed to be low dead space. Needle hub208C may be as described herein, and/or other known designs. A smaller volume of fluid210C is retained, which is less than volume of fluid210A retained by syringe202A and less than volume of fluid210B retained by syringe202B.

Syringe202D is a known special design that is an integrated barrel and plunger206D fixed to a needle hub208D. Since the entire syringe202D is integrated and fixed, needle hub208D is not a separate component and cannot be used with different separate barrel and plunger components. Although retained volume210D is low, and may be lower than volumes210A-C of syringes210A-C, this comes at the cost of limiting the user to using this specific syringe. The user is required to obtain syringe202D as a whole from a specific manufacturer. The user is not provided with the ability to select different barrel and plungers.

Moreover, another known design (not shown) includes barrel and plunger components which are separate from the needle hub. The needle hub is designed to retain a low volume of fluid after plunger has been fully pressed. Although potentially the user may select the barrel and plunger to connect to the needle hub, the needle hub is not designed to comply with standards such as ISO guidelines, and therefore, the barrel and plunger that are able to connect to the needle hub are specialize products available only from specific manufacturers, which severely limits the ability of the user to use standard components from different manufactures. Even in implementations in which standard barrel and plungers may fit the specialized needle hub, the resulting syringe does not comply with standards such as ISO guidelines, and may experience other failures, such as stability issues, leakage of fluid, and the like.

In contrast, as described herein, syringe202is assembled from a needle hub assembly220described herein, which is sized and/or shaped to fit standard barrels and plunger222components. The improvement is in the flat bottom of a cylindrical depression of the needle hub assembly220, and the shape and/or size of the interior walls of the cylindrical depression, that minimize space between the interior of the cylindrical depression when the nozzle of the barrel222is located within the cylindrical depression. This design reduces an amount of retained fluid224, which may be less than fluid210A-D of syringes202A-D. The amount of retained fluid224is especially reduced when a standard low dead weight plunger is used.

For example, standard needle hubs retain about 0.0192 milliliter (mL) or about 19 microliters. The needle hub assemble described herein retains about 0.0052 mL or about 5 microliters.

It is noted that in some prior designs, a hub connector of the needle hub designed to connect to a barrel and plunger is not flat, but includes an elevation (e.g., bump). This elevation prevents the nozzle from contacting the bottom surface of the hub connector. When the nozzle contacts the elevation, a space is formed between the nozzle and the bottom surface (i.e., the rest of the hub connector in proximity to the elevation, but not part of the elevation) which retains fluid after the plunger is maximally displaced.

As used herein, the terms distal and proximal are with reference to a user holding an assembled syringe in a position ready for injection (e.g., into a subject). Components of the syringe closer to the user (and further away from the subject) are termed proximal, and components further away from the user (and closer to the subject) are termed distal.

As used herein, ISO standards are current and/or past standards. It is to be understand that future ISO standards may be defined, and/or new versions and/or updates of existing standards may be created, and the term ISO standard is meant to cover past, current, and future relevant ISO standards.

Reference is now made toFIG.2, which is a schematic depicting a cross sectional slice of a needle hub assembly102for connecting to a barrel with plunger for assembling a syringe that has a low retained volume after the plunger is maximally displaced (i.e., pressed) to expel fluid within the barrel, in accordance with some embodiments of the present invention.

The following is a list of elements used in labellingFIG.2:102Needle hub assembly104cylindrical depression106proximal end of needle hub assembly108flat bottom110longitudinal axis112lumen114distal end of the needle hub116cannula118proximal cannula portion120depth122edge of proximal end124A-B flares126proximal lumen portion128distal lumen portion130junction of proximal lumen portion and distal lumen portion132opening into cylindrical depression134distal cannula portion136fluid flow line138space formed between exterior surface of proximal cannula portion and interior surface of tapered distal lumen portion140adhesive/support element142inner surface of cylindrical depression144external surface

Needle hub assembly102includes a cylindrical depression104in a proximal end portion106thereof. Cylindrical depression104is a hub connector component, designed to connect to a hub. Cylindrical depression has a flat bottom108. Flat bottom108is arranged perpendicular to a longitudinal axis110of needle hub assembly102. The flat bottom108enables contact between a surface proximal to an opening of a nozzle of the barrel when the barrel is connected to need hub assembly102by being disposed within cylindrical depression104. Cylindrical depression104is sized and/or shaped for contacting between an interior surface142of the cylindrical depression104and an exterior surface of the nozzle along a longitudinal axis of the nozzle. Interior surface142of the cylindrical depression extends from the flat bottom108to a depth120away from an edge122of the proximal end portion106. The interior surface located at the depth120region may include elements designed to secure the nozzle, for example, a screw. The contact between the cylindrical depression104and the nozzle is designed to be sealed, i.e., fluid tight, such that fluid existing from an opening in the nozzle is entirely forced into an opening of a lumen112in the flat bottom108without having a space for existing between the cylindrical depression104and the nozzle.

Lumen112extends from the flat bottom108of the cylindrical depression104to a distal end portion114of the needle hub assembly. A cannula116, for example, a needle, having a proximal cannula portion118is located within the lumen, in particular within a distal lumen portion128. A distal cannula portion134of the cannula116extends distally from the distal end portion106of the needle hub assembly102.

Cylindrical depression104, lumen112and cannula116are sized and shaped to enclose a volume of about 0.0052 milliliters (mL) when a low dead space plunger is fully plunged into the barrel connected to the cylindrical depression104. The amount of fluid remaining in cannula116, a proximal lumen portion126portion of the lumen (i.e., that that does include the cannula), and a space formed by the nozzle, flat bottom108of the cylindrical depression104, and interior walls142of the cylindrical depression, after the plunger has been fully displaced (i.e., pressed) to inject fluid contents of the barrel, is designed to be low, for example, about 0.0052 mL or about 5 microliters, which may be lower than other syringe designs, in particular other syringes assembled from other needle hubs that are compliant with ISO guidelines, as described herein. This provides a savings of up to about 0.014 mL or about 14 microliters of fluid (e.g., vaccine, medicine, botox, anesthetic) in comparison to using standard hubs, barrels, and plungers, for example, as experimentally verified by Inventors and as described with reference to the “Examples” section below.

Dimensions and/or sizing of needle hub assembly102are selected to be in compliance with standards, for example, ISO standards, such as ISO 594-1. This enables needle hub assembly102to connect to any barrels and plungers that are also compliant with the same standards, providing the user with the ability to select off the shelf barrels and/or plungers, for example, of different sizes, shapes, and/or manufactures. For example a depth of the cylindrical depression104measured from edge122of proximal end106of the needle hub assembly, parallel to the longitudinal axis110may be greater than 7 millimeters (mm). In some implementations, the depth is equal to 7 mm.

It is noted that in another prior known hub design, the length of a barrel connector of a hub designed to connect to a barrel is non-compliant with ISO guidelines, or minimally compliant with ISO guidelines (e.g., having a size at the limit of the ISO guidelines).

Optionally, dimensions of inner surface142of cylindrical depression104are selected for compliance with guidelines, optionally ISO guidelines, for example, ISO 80369-7. Dimensions of inner surface142may be set to a 6% Luer tap and/or sized and/or shaped Dimensions of a bottom surface.

Optionally, dimensions of hub102and/or cylindrical depression104are selected to be compliance with standards, optionally ISO guidelines such as 7864, for fitting Luer Slip and/or Luer Lock Tip barrels, syringes, and/or other medical devices with compliant tip connectors.

Needle hub assembly102may include a pair of flares (124A-B) extending outwardly from opposite locations of an external surface144of needle hub assembly102, at a location corresponding to an end of proximal end portion106of the needle hub assembly102, such as extending from edge122of proximal end portion106. The dimensions of flares124A-B and/or dimensions of external surface144of needle hub assembly102may be compliant with7864for fitting Luer Slip and/or Luer Lock Tip barrels, syringes, and/or other medical devices with compliant tip connectors. For example, a length from an end of a first flare124A to an end of a second flare124B perpendicular to the longitudinal axis110is about 7.8 millimeters and a diameter of the first end portion excluding the pair of flares124A-B is about 6.7 mm. Lumen112includes a proximal lumen portion126and a distal lumen portion128. Proximal lumen portion126has a constant internal diameter along a length thereof. One end of proximal lumen portion126has opening132into flat bottom108of cylindrical depression104. The opposite end of proximal lumen portion126connects to distal lumen portion128at a junction130. Distal lumen portion128has a tapered diameter increasing in diameter from junction130with proximal lumen portion126towards an opening at the distal end portion114of the needle hub assembly102.

Fluid flows along a flow flowing channel136, substantially parallel to longitudinal axis110, in response to plunger being displaced (i.e., pressed) when barrel is connected to needle hub assembly102, for example, during injection of the fluid. Needle hub assembly102is designed to generate flowrate consistency of the flowing fluid in response the plunger being displaced, by having a constant internal diameter dimension along flow rate line136, from opening132of flat bottom108of cylindrical depression104until fluid exits the tip of cannula116.

Proximal cannula portion118is located within distal lumen portion128. Cannula116is not disposed within proximal lumen portion118. At junction130, cannula116is in continuity with distal lumen portion128. Cannula116has a constant inner diameter along a length thereof, that matches a constant inner diameter of distal lumen portion128. The continuity of the constant inner diameters forms a fluid flowing channel136with continuous constant inner diameter for fluid flowing from the barrel via opening132of flat bottom108of cylindrical depression104via proximal lumen portion126and through cannula116.

The constant inner diameter improves efficiency of the flowing fluid, for example, creating laminar flow, and/or reducing and/or avoiding turbulent flow which may create complications during injections and/or avoid unnecessary required applied force to depress the plunger.

Optionally, an adhesive is disposed within a space138formed between an exterior surface of proximal cannula portion118disposed within the lumen112(i.e., within the distal lumen portion128) and an interior surface of the tapered distal lumen portion128. The adhesive provides a strong bonding force between cannula116and needle hub assembly102, for example, for preventing cannula116from detaching from needle hub assembly102, and/or for preventing cannula116from bending.

Optionally, the adhesive extends externally from the space138. The portion of the adhesive external to space138, extending above distal end portion114of needle hub assembly, may form a cone and/or convex shaped support140. The wider base of support element140is connected to the end surface of the distal end portion114of the needle hub assembly102perpendicular to the longitudinal axis110. Cannula116extends through an interior of the support element140. Alternatively, support element140is separate from the adhesive in space138, for example, another adhesive separately applied, and/or a molding of distal end portion114of needle hub assembly into the convex and/or cone shape.

Support element140is positioned to support a portion of cannula116extending past the distal end portion114of the needle hub assembly102by supporting the portion of cannula116extending through the interior of support element140and/or by connecting the portion of cannula116extending through the interior of support element140with the end surface of the distal end portion114of the needle hub assembly102.

Support element140is designed to provide additional support to cannula116, to avoid and/or reduce risk of bending during injections.

Cannula116may be implemented as, for example, a needle (e.g., for injection into a subject) and/or tubing (e.g., connected to an IV drip).

Cannula116may be made, for example, using medical silicon, metal, and/or other medical grade materials. Cannula116may be made of materials that comply with a standard(s), such as ISO standard(s), for example, ISO 9626.

Cannula116may be lubricated by medical silicon fluid. The lubrication with medical silicon is designed to provide a smooth penetration force during injection into tissue of a subject.

A bevel angle142of cannula116may be a triple point, optionally that complies with a standard(s), such as ISO standard(s), for example, ISO 7864.

Reference is also made toFIG.3, which is a schematic depicting a side perspective view of needle hub assembly102described herein and/or with reference toFIG.2, in accordance with some embodiments of the present invention. Dimensions350of cylindrical depression104and/or dimensions352of needle hub assembly102are selected to comply with relevant ISO standards, as described herein.

Reference is also made toFIG.4, which is a schematic depicting a face-on/top view perspective view of needle hub assembly102described herein and/or with reference toFIG.2, in accordance with some embodiments of the present invention. Dimensions450of needle hub assembly102are selected to comply with relevant ISO standards, as described herein.

Reference is now made toFIG.5, which is a schematic depicting a perspective view of needle hub assembly102showing cannula116described herein and/or with reference toFIG.2, in accordance with some embodiments of the present invention.

Reference is now made toFIG.6, which is the schematic of needle hub assembly102depicted inFIG.2, indicating exemplary dimensions that comply with ISO standards, in accordance with some embodiments of the present invention.

Reference is now made toFIG.7, which is the schematic of needle hub assembly102depicted inFIG.3, indicating exemplary dimensions that comply with ISO standards, in accordance with some embodiments of the present invention.

Reference is now made toFIG.8, which is the schematic of needle hub assembly102depicted inFIG.4, indicating exemplary dimensions that comply with ISO standards, in accordance with some embodiments of the present invention.

It is expected that during the life of a patent maturing from this application many relevant barrels, plungers, needles, syringes, and cannulas will be developed and the scope of the terms barrel, plunger, needle, syringe, and cannula are intended to include all such new technologies a priori.

As used herein the term “about” refers to ±10%.

The term “consisting of” means “including and limited to”.

EXAMPLES

Inventors performed experiments to measure the amount of fluid retained by syringes assembled from needle hub assemblies based on embodiments described herein, connected to standard hubs and plungers, after the plunger has been fully pressed to expel fluid loaded within hub. This emulates, for example, amount of “dead” fluid which is lost after administering a vaccine.

Materials

Inventors created two syringes.

A first syringe was created by connecting the needle hub assemblies based on embodiments described herein, to standard 1 mL Luer Slip Tip barrel and plunger.

A second syringe was created by connecting a standard needle hub assembly to the standard 1 mL syringe Luer Slip Tip.

The first syringe was filled with colored water.

The second syringe was filled with colored water.

Methods

First Syringe (Including Hub Assembly Based on Embodiments Described Herein):

The weight of the first syringe filled with water was 2.4349 grams.

Following the weighing of the first syringe filled with water, the plunger was pressed to its maximal displacement to expel as much water as possible. The weight of the first syringe with retained water was weighed. The weight of the first syringe with retained was 2.4137 grams.

The total amount of dead space (i.e., retained water) of the syringe was calculated as 2.4349−2.4137=0.0212 grams, which is 0.0212 mL.

The total dead space of the standard 1 mL Luer Slip Tip barrel and plunger is known to be 0.016 mL.

The total dead space of the needle hub assembly based on embodiments described herein was calculated as 0.0212−0.016=0.0052 mL.

The weight of the second syringe filled with water was 2.4036 grams.

Following the weighing of the second syringe filled with water, the plunger was pressed to its maximal displacement to expel as much water as possible. The weight of the second syringe with retained water was weighed. The weight of the second syringe with retained was 2.3684 grams.

The total amount of dead space (i.e., retained water) of the syringe was calculated as 2.4036−2.3684=0.0352 grams, which is 0.0352 mL.

The total dead space of the standard 1 mL Luer Slip Tip barrel and plunger is known to be 0.016 mL.

The total dead space of the standard needle hub assembly was calculated as 0.0352−0.016=0.0192 mL.

CONCLUSION

The volume retained by the needle hub assembly based on embodiments described herein was measured to be 0.0052 mL or 5 microliter, which is significantly less than the volume retained by the standard needle hub assemble which was measured to be 0.0192 mL or 19 microliters.

Using the needle hub assembly based on embodiments described herein saves up to about 0.0014 mL or 14 microliters (i.e., ie 0.0192 mL-0.0052 mL) of fluid in comparison to using standard components of standard syringes (i.e., standard hub, standard barrel, and standard plunger).