AU2019101296A4

AU2019101296A4 - Infusion Pump

Info

Publication number: AU2019101296A4
Application number: AU2019101296A
Authority: AU
Inventors: Mark Bennett
Original assignee: Multigate Medical Devices Pty Ltd
Current assignee: Multigate Medical Devices Pty Ltd
Priority date: 2019-10-25
Filing date: 2019-10-25
Publication date: 2019-12-19
Anticipated expiration: 2027-10-25

Abstract

Abstract The invention provides an infusion pump of the type which can be used for providing fluid from a fluid source to the body of a patient. The infusion pump has an inlet end having a fluid inlet and an outlet end having a fluid outlet; a flexible pump jacket defining a 5 pumping chamber located between the inlet end and the outlet end; an inlet hub attached to the pump jacket at the inlet end; an outlet hub attached to the pump jacket at the outlet end; a directional valve adapted to allow fluid flow in a direction from the inlet end to the outlet end but to inhibit fluid flow in a direction from the outlet end to the inlet end; and optionally a bypass flow pathway from the fluid inlet to the fluid outlet, 10 the bypass fluid pathway extending through the pump jacket while bypassing the directional valve. The directional valve has a flap portion, extending in a first direction and having a free end, and a stabilizing portion extending in a second direction being substantially perpendicular to the first direction. The flap portion and the stabilizing portion form a 15 corner having a greater thickness than the free end of the flap portion. _3/9 'JI

Description

INFUSION PUMP

Field of the Invention

This invention relates to an infusion pump of the type which can be manually operated and used in the medical field, such as for providing irrigation fluid to a surgical site or for pumping blood or other fluids.

For convenience below, the invention will often be described in relation to its use in arthroscopic surgery. However, it is to be understood that this does not limit the scope of the invention.

Background of the Invention

International patent specification No. WO 2013/102236 (referred to below as the International Application) discloses a manually operated medical pump for use in medical applications. The present invention represents one or more advancements in the pump disclosed in the International Application. For convenience, the contents of the International Application are incorporated herein by reference.

Arthroscopic surgery involves making a small incision in the body, for example in a knee of the patient. An optical fibre scope is inserted so that vision can be transmitted to a monitor. During the surgery, a fluid flow is used to clear the site of debris and blood in order to maintain vision. From time to time, a bolus of fluid is applied to the site, for example when required to expand the body cavity or joint or for flushing stubborn debris.

A manual pump or infusion pump may be used to provide the fluid flow from one of more fluid sources. A typical fluid source is a bag of sterile saline solution, set up at an elevated position so that the fluid can flow into the pump by gravity. The pump is typically capable of providing a bolus of fluid when squeezed manually.

It is important that the infusion pump used is capable of providing a continuous, steady flow of the fluid for normal irrigation, as well as an increased flow on demand for providing the bolus when required.

While the medical pump disclosed in the International Application had merit, there were drawbacks.

The medical pump disclosed in the International Application had flap valves intended to allow fluid flow from the inlet to the outlet, but to inhibit backflow - namely, flow of the fluid from the outlet to the inlet. The flap valves were arranged in the inlet hub and in the outlet hub. Pressure from the gravity feed from the fluid source kept the flap valves open so that fluid could flow from inlet to the outlet. However, especially when the jacket was squeezed to create a bolus of fluid, the flap valves in the inlet hub were susceptible to collapse, thus allowing backflow up a bypass tube. This in turn interfered with the ability of the pump to deliver a bolus of fluid.

In addition, the medical pump disclosed in the International Application could be used for pumping other fluids, such as blood, as well as for pumping saline solution in arthroscopic surgery. Blood is heavier and more viscous than saline solution. As a result, more force may be required in squeezing the pump. In addition, the flap valves in the inlet hub were even more inclined to collapse, increasing likelihood of backflow.

It is therefore an object of the present invention to provide an infusion pump which overcomes or alleviates the problems associated with the prior art medical pump or which at least provides a useful alternative.

In embodiments described in the International Application, the medical pump could be difficult to assemble. It is an object of this invention, at least in some embodiments, to provide an infusion pump which is relatively easy to assemble.

Summary of the Invention

In the present invention, the flap valve of the International Application has been replaced by a novel valve which is superior to the prior art flap valve in preventing backflow.

Accordingly, the present invention provides an infusion pump for providing fluid from a fluid source to the body of a patient, the infusion pump including:

- an inlet end having a fluid inlet and an outlet end having a fluid outlet;

- a flexible pump jacket defining a pumping chamber located between the inlet end and the outlet end;

- an inlet hub attached to the pump jacket at the inlet end;

- an outlet hub attached to the pump jacket at the outlet end; and

- a directional valve adapted to allow fluid flow in a direction from the inlet end to the outlet end but to inhibit fluid flow in a direction from the outlet end to the inlet end;

wherein the directional valve has a flap portion, extending in a first direction and having a free end, and a stabilizing portion extending in a second direction being substantially perpendicular to the first direction;

and wherein the flap portion and the stabilizing portion form a corner having a greater thickness than the free end of the flap portion.

In the infusion pump of the invention there may be a plurality of fluid inlets and/or fluid outlets

In one embodiment, the infusion pump of the invention also has a bypass flow pathway from the fluid inlet to the fluid outlet, the bypass fluid pathway extending through the pump jacket while bypassing the directional valve.

In that embodiment, the infusion pump of the invention has a cylindrical pump jacket containing the bypass flow pathway in the form of a tube centrally located within the pumping chamber. It is preferred that the tube in this embodiment is a one-piece tube, extending from the inlet (optionally, from outside the inlet) and through the pumping chamber, terminating in close proximity to the outlet. This embodiment is in contrast to the bypass flow pathway described in the International Application, where the bypass flow pathway was made up of an outer bypass tube, a nozzle at the inlet end and a nozzle at the outlet end. The nozzles were inserted into the outer bypass tube, creating impediments to laminar flow of fluid. In simplifying the bypass tube, such a drawback can be avoided and assembly is facilitated.

If the bypass tube is not present, the flexible pump jacket may still be cylindrical, this configuration being convenient for squeezing when a bolus of fluid is required.

It is preferred that each of the inlet hub and the outlet hub is provided as a cap which fits around an extremity of the pump jacket. This arrangement can form a better seal than the embodiments in the International Application and can streamline assembly.

The infusion pump of the invention may be made from any suitable material of combination of materials. Typically, the pump is made from plastic materials. The pump jacket may be made from polyvinylchloride (PVC), as may the bypass tube, if present. Optionally, the pump jacket and any bypass tube may be fully or partially transparent, to allow inspection of fluid.

In a preferred embodiment, the inlet and outlet hubs are made of the same material as the pump jacket, so that the seal between the pump jacket and the hubs is not compromised. This is especially preferred if the inlet and outlet hubs are welded to the pump jacket ultrasonically.

If the inlet and outlet hubs are made of material different from that of the pump jacket, they may be bonded to the pump jacket by a bonding agent suitable to chemically bond the two different materials.

It is preferred that the directional valve is seated against a web of a seal cap containing apertures, so that the flap portion of the valve opens to allow flow of fluid through the aperture from the inlet to the outlet, but closes to inhibit backflow. The web in this embodiment may be generally as disclosed in the International Application, having a plurality of apertures arranged about a central aperture, which can accommodate the bypass tube if present. However, it is preferred that the apertures are located more towards the circumference of the web than close to the central aperture or bypass tube. It is further preferred that each aperture is elongated circumferentially, rather than being circular. Examples are shown in the accompanying drawings, and described below.

There is preferably a plurality of directional valves. In particular, it is preferred that there are two directional valves, one associated with the inlet hub and the other associated with the outlet hub.

The directional valve is preferably made of silicone or similar material. The valve may be located in the outlet hub and not in the inlet hub. It is preferred that a directional valve is located in both hubs. However, a directional valve in the outlet hub is preferably of more robust construction than a directional valve in the inlet hub. For example, the stabilizing portion in the outlet hub may be longer or otherwise more substantial that the stabilizing portion of the valve in the inlet hub. In addition, or alternately, the thickness at the corner between the flap portion and the stabilizing portion may be greater for a directional valve in the outlet hub, compared to a directional valve in the inlet hub.

In a preferred embodiment, the stabilizing portion of the directional valve is supported by a retaining clip, an example being shown in the accompanying drawings. The retaining clip in this embodiment has a ledge supporting an end of the stabilizing portion. Preferably, when there is a directional valve in each of the inlet and outlet hubs, the stabilizing portion in each is supported by a retaining clip.

The seal cap is preferably designed so that, when two directional valves of different sizes are included, the same seal cap can accommodate both sizes. For this purpose, the seal cap may have an inner rim on one side of the web and a rim extension on the opposite side of the web. If, for example, the rim extension is longer than the inner rim, the stabilising portion of the smaller valve may fit into inner rim, while the stabilising portion of the larger valve may fit into the rim extension.

In another embodiment, the seal cap may omit the rim extension.

Brief Description of the Drawings

A preferred embodiment of the present invention will now be described with reference to the accompanying drawings. It is to be understood that the embodiment described is not intended to be limiting on the scope of the invention. Changes, modifications and variations may be made without departing from the spirit and scope of the present invention.

In the drawings:

Figure 1 is a perspective view of an embodiment of the infusion pump according to the invention, having a bypass tube;

Figure 2 is a side elevation of the embodiment of Figure 1;

Figure 3 is a left-hand end view of the infusion pump shown in Figure 2;

Figure 4 is a right-hand end view of the infusion pump shown in Figure 2;

Figure 5 is a sectional view of the infusion pump, along the line A-A in Figure 3;

Figure 6 is a sectional view taken along the line D-D in Figure 5;

Figure 7 is a detailed view of the section indicated as C in Figure 5;

Figure 8 is a detailed view of the left-hand end of the infusion pump, labelled B in Figure 5;

Figure 9 is a side view of a second embodiment of a seal cap for the outlet end of the infusion pump (left hand end shown in Figures 1 and 2);

Figure 10 is a front view of the seal cap of Figure 9, viewed from the left of Figure 9;

Figure 11 is a sectional view taken along the line E-E in Figure 10;

Figure 12 is a side view of a second embodiment of a seal cap for the inlet end of the infusion pump (right hand end shown in Figures 1 and 2);

Figure 13 is a front view of the seal cap of Figure 12, viewed from the right of

Figure 12;

Figure 14 is a sectional view of the seal cap for the inlet end, corresponding to that in Figure 11 for the seal cap for the outlet end;

Figure 15 is a perspective view of an embodiment of the infusion pump according to the invention, without a bypass tube;

Figure 16 is a side elevation of the embodiment of Figure 15;

Figure 17 is a left-hand end view of the infusion pump shown in Figure 16;

Figure 18 is a longitudinal sectional view of the infusion pump, along the line A-A in Figure 17;

Figure 19 is a sectional view taken along the line B-B in Figure 18;

Figure 20 is a detailed view of the sectional view of Figure 18;

Figure 21 is a detailed view of the right-hand end of the sectional view of Figure 18; and

Figure 22 is a detailed view of the left-hand end of the sectional view of Figure 18.

Some of the drawings are of differing scales in order to better illustrate detail.

Description of Preferred Embodiments

As illustrated in Figures 1 to 4, the embodiment of the infusion pump 10 has an inlet end 12 and an outlet end 14. At inlet end 12 there are two fluid inlets: bypass fluid inlet 16 and pumping chamber inlet 18. At outlet end 14 there is a single fluid outlet 20.

Pump jacket 22 is cylindrical and is attached to inlet hub 24 at inlet end 12 and to outlet hub 26 at outlet end 14. Pump jacket 22 is flexible, so that it may be squeezed manually to produce a bolus of fluid.

Turning now to Figure 5 showing a sectional view of pump 10, bypass fluid inlet 16 is integral with bypass tube 28, which is a one-piece tube centrally located within pumping chamber 30. Bypass tube 28 provides a bypass flow pathway from fluid inlet 16 to fluid outlet 20. Bypass tube 28 extends through pump jacket 22 and ends in close proximity to fluid outlet 20.

Pumping chamber inlet 18 communicates with intake chamber 32.

Figure 7 shows an expanded view of details of inlet end 12 and inlet hub 24. Seal cap 34, which is mounted on bypass tube 16, is shown separately in Figure 6 and has an upstanding outer rim 36 about a web 38. Apertures 40 (only one is labelled) through web 38 allow passage of fluid, subject to directional valve 42. Apertures 40 are elongated circumferentially and located closer to rim 36 than to bypass tube 28.

Directional valve 42 is annular and has a flap portion 44 extending in a first direction from near bypass tube 28 towards the outer circumference of pump jacket 22. Flap portion 44 has free end 46. Valve 42 has a stabilizing portion 48 extending in a second direction, being substantially perpendicular to the first direction and parallel with bypass tube 28. Stabilizing portion 48 is supported by a retaining clip 80 which is more clearly shown in Figure 14 in connection with a second embodiment of the seal cap for the inlet end 12.

Corner 50 is formed between flap portion 44 and stabilizing portion 48. In and around corner 50 the material of valve 42 is thicker than at free end 46 of flap portion 44. About half of flap portion 44 is approximately the same thickness as at end 46. This enables flap portion 44 to open under pressure from gravity-fed fluid from pumping chamber inlet 18, so that fluid can flow from the fluid source (not shown), along pumping chamber inlet 18, into intake chamber 32, through apertures 40 (see Figure 6) and into pumping chamber 30 enclosed by pump jacket 22.

Stabilizing portion 48 together with the thicker material at corner 50 of valve 42 causes flap 44 to close against apertures 40 to inhibit backflow, when pump jacket 22 is squeezed during use.

It will be noted that stabilizing portion 48 is shorter than flap portion 44 in valve 42. This can be contrasted with valve 62, described below in connection with Figure 8.

Figure 7 also shows that seal cap 34 has an inner rim 54, which, together with rim extension 56, functions to stabilize seal cap 34 against bypass tube 28.

Valve 42 is fixed to seal cap 34 at corner 50 and along stabilizing portion 48, leaving flap portion 44 free.

It will be noted that fluid passing through bypass tube 28 bypasses directional valve 42.

Pump jacket 22 is sandwiched between outer rim 36 of seal cap 34 and wall 58 of inlet hub 24, which is adhered or otherwise fixed to pump jacket 22. Wall 58 lies outside of pump jacket 22. This arrangement creates an easy to assemble, stable construction.

Ferrules 59 form part of inlet hub 24 and serve to stabilise bypass fluid inlet 16 (part of bypass tube 28) and pumping chamber inlet 18.

Figure 8 shows an expanded view of details of outlet end 14 and outlet hub 26. End 52 of bypass tube 28 lies close to outlet 14.

Seal cap 34 (Figure 6) is mounted on bypass tube 28 in a mirror reverse configuration to that in inlet hub 24. Inner rim 54, which, together with rim extension 56, functions to stabilize seal cap 34 against bypass tube 28, is located facing pumping chamber 30, while rim extension 56 is located facing outlet hub 26. It will be noted from Figure 7 that for seal cap 34 in inlet hub 24, inner rim 54 is located facing pumping chamber 30 while rim extension 56 is located facing inlet hub 24.

Directional valve 62 is annular and similar, but not identical, to directional valve 42, being more robust that valve 42. Directional valve 62 has a flap portion 64 extending in a first direction from near bypass tube 28 towards the outer circumference of pump jacket 22. Flap portion 64 has free end 66. Valve 62 has a stabilizing portion 68 extending in a second direction, being substantially perpendicular to the first direction and parallel with bypass tube 28.

Corner 60 is formed between flap portion 64 and stabilizing portion 68. In and around corner 60 the material of valve 62 is thicker than at free end 66 of flap portion 64, and tapers towards free end 66. This enables flap portion 64 to open under pressure from gravity-fed fluid from pumping chamber 30, so that fluid can flow into outlet chamber 70, through apertures 40 (see Figure 6).

Stabilizing portion 68 together with the thicker material at corner 60 of valve 62 biases flap 64 to close against apertures 40. When pump jacket 22 is squeezed, flap 64 is forced open to emit a bolus of fluid from chamber 30 into outlet chamber. Flap 64 is restored to the closed position under the influence of stabilizing portion 68 and the thickness of corner 60, allowing chamber 30 to refill with fluid.

Flap 64 of valve 62 has more resistance to opening than flap 44 of valve 42, to cope with the greater load represented by fluid in pumping chamber 30.

Stabilizing portion 68 is supported by a retaining clip 80 which is more clearly shown in Figure 11 in connection with a second embodiment of the seal cap for the outlet end 14.

Pump jacket 22 is sandwiched between outer rim 36 of seal cap 34 and wall 72 of outlet hub 26, which is adhered or otherwise fixed to pump jacket 22. Wall 72 lies outside of pump jacket 22. This arrangement creates an easy to assemble, stable construction.

Valves 42 and 62 are designed so that when fluid from a suspended fluid source (not shown) passes into the infusion pump 10, the fluid flows through the pump 10 under gravity, including when the pump jacket 22 is not being squeezed manually. However, when manual pressure is applied to pump jacket 22, a bolus of fluid is forced from pumping chamber 30, through valve 62, into outlet chamber 70 and out through outlet

14. From there, the bolus of fluid travels down a tube and through a trocar (neither shown) into the surgical site to effect the necessary flushing or expansion.

At the same time, fluid from the fluid source travels unimpeded from bypass fluid inlet 16, through bypass tube 28 and out of fluid outlet 20.

Seal cap 34 is designed so that stabilising portion 48 of smaller valve 42 fits into inner rim extension 54 when seal cap 34 is used at the inlet hub 24, while stabilising portion 68 of larger valve 62 fits into rim extension 56 when seal cap 34 is used at the outlet hub 26.

In the embodiment shown in Figures 9 to 14, the same labels are used to refer to parts which are the same in both embodiments. Where there are differences, the labels used for the second embodiment have a prefix '1'.

Figures 9 to 14 illustrate a different embodiment of seal cap 134A and 134B, compared to seal cap 34 shown in Figures 5 to 8. However, the retaining clip for the stabilizing portion of the directional valve is the same in both embodiments.

It will be appreciated that although Figure 10 is a front view of the seal cap 134A of Figure 9, viewed from the left of Figure 9, the front view of the seal cap 134B of Figure 12, also viewed from the left of Figure 12, would be very similar. In addition, the view of seal cap 134B of Figure 13, viewed from the right of Figure 12, would be very similar to a view of seal cap 134A when viewed from the right of Figure 9.

Seal cap 134A is intended to be mounted on bypass tube 28 in place of seal cap 34 at outlet hub 26. Seal cap 134A has an upstanding outer rim 136 about a web.

Seal cap 134A is designed so that pump jacket 22 can overlie outer rim 136 of seal cap 134A, abutting flange 137. Wall 72 of outlet hub 26 can then sandwich pump jacket 22, as shown for the previous embodiment of seal cap 34 in Figure 8. Once again, this arrangement creates an easy to assemble, stable construction.

Directional valve 62 is the same as in the previous embodiment - see Figure 8, for example, having flap portion 64 which, when seal cap 134A is in situ at outlet hub 26, extends in a first direction from near bypass tube 28 towards the outer circumference of pump jacket 22. Flap portion 64 has free end 66. Valve 62 has stabilizing portion 68 extending in a second direction, being substantially perpendicular to the first direction and parallel with bypass tube 28. Corner 60 is formed between flap portion 64 and stabilizing portion 68.

As can be seen in Figure 11, stabilizing portion 68 has an end 74 which abuts ledge 76 of retaining clip 80. Retaining clip 80 supports and retains stabilizing portion 68.

It may be noted that seal cap 134A does not have the inner rim 54 of seal cap 34. Otherwise, seal cap 134A is similar to seal cap 34 when in position in outlet hub 26.

Seal cap 134B, however, has more differences compared to seal cap 34 as shown in position in inlet hub 24 in Figure 7. Seal cap 134B is intended to be mounted on bypass tube 28 in place of seal cap 34 at inlet hub 24.

Seal cap 134B has an upstanding outer rim 78 about a web 138 and is designed so that pump jacket 22 can overlie outer rim 78 of seal cap 134B, abutting flange 81. Wall 58 of inlet hub 24 can then sandwich pump jacket 22, as shown for the previous embodiment of seal cap 34 in Figure 7. Once again, this arrangement creates an easy to assemble, stable construction.

Like directional valve 42, valve 142 is annular and has a flap portion 44 extending in a first direction from near bypass tube 28 towards the outer circumference of pump jacket 22. Flap portion 44 has free end 46. Valve 142 has a stabilizing portion 148 extending in a second direction, being substantially perpendicular to the first direction and parallel with bypass tube 28. Stabilizing portion 148 is longer than stabilizing portion 48 of valve 42. But each of stabilizing portions 48 and 148 is supported by a retaining clip which is more clearly shown in Figure 14.

As in the case of the embodiment of valve 42, corner 150 is formed between flap portion 44 and stabilizing portion 148. In and around corner 150 the material of valve 142 is thicker than at free end 46 of flap portion 44. About half of flap portion 44 is approximately the same thickness as at end 46. This enables flap portion 44 to open under pressure from gravity-fed fluid from pumping chamber inlet 18, so that fluid can flow from the fluid source (not shown), along pumping chamber inlet 18, into intake chamber 32, through apertures 140 (see Figure 13) and into pumping chamber 30 enclosed by pump jacket 22.

Stabilizing portion 148 together with the thicker material at corner 50 of valve 142 biases flap 44 to close against apertures 140.

In contrast to the previous embodiment, stabilizing portion 148 is approximately the same length as flap portion 44.

As can be seen in Figure 14, stabilizing portion 148 has an end 82 which abuts ledge 84 of retaining clip 80. Retaining clip 80 supports and retains stabilizing portion 148.

It may be noted that seal cap 134B does not have the rim extension 56 of seal cap 34 and, when in situ in inlet hub 24, seal cap 134B may be located closer to pumping chamber inlet 18, compared to seal cap 34.

Turning now to the embodiment is Figures 15 to 22, it will be appreciated that this embodiment does not include a bypass tube.

As illustrated in Figures 15, 16 and 18, this embodiment of the infusion pump 110 has an inlet end 112 and an outlet end 114. At inlet end 112 there is a single fluid inlet, being pumping chamber inlet 118. At outlet end 114 there is a single fluid outlet 120.

Pump jacket 22 is the same as that in the previous embodiment, being cylindrical and attached to inlet hub 124 at inlet end 112 and to outlet hub 126 at outlet end 114. Pump jacket 22 is flexible, so that it may be squeezed manually to produce a bolus of fluid.

Seal cap 234B is shown separately in Figure 20 and in side section in Figure 21. A comparison of Figure 21 with Figure 14 shows that seal cap 234B is very similar in side section to seal cap 134B in Figure 14. Retaining clip 180 is shown in Figure 21.

Figure 20 shows that seal cap 234B has similarities with seal cap 134B in Figure 13. Apertures 240 (only one is labelled) through web 238 allow passage of fluid, subject to directional valve 142, described earlier. Upstanding outer rim 278 surrounds web 238 and is designed so that pump jacket 22 can overlie outer rim 278 of seal cap 234B, abutting flange 281. Wall 258 of inlet hub 124 can then sandwich pump jacket 22, as shown for the previous embodiment of seal cap 34 in Figure 7. Once again, this arrangement creates an easy to assemble, stable construction.

Directional valve 142 is essentially the same as in Figure 14 and need not be described again.

2019101296 25 Oct 2019

Turning now to Figure 22, seal cap 234A is shown in situ near the outlet end of pump 110. It will be appreciated that seal cap 234A is very similar to seal cap 234B, flange 281 in seal cap 234B being replaced by flange 237 in seal cap 234A. A comparison of Figure 22 with Figure 11 shows that seal cap 234A is very similar in side section to seal cap 134A in 5 Figure 11. Retaining clip 180 is shown in Figure 22.

Seal cap 234A is designed so that pump jacket 22 can overlie outer rim 236 of seal cap 234A, abutting flange 237. Wall 172 of outlet hub 126 (Figure 16) can then sandwich pump jacket 22, as shown for the previous embodiment of seal cap 34 in Figure 8. Once again, this arrangement creates an easy to assemble, stable construction.

Directional valve 62 is the same as in the previous embodiment - see Figure 11, for example, and need not be further described.

Industrial Applicability

Embodiments of the invention can provide an infusion pump which is easy to use for providing irrigation fluid to a surgical site or for pumping blood or other fluids. The 15 infusion pump can deliver a continuous, steady flow of the fluid for normal irrigation, as well as an increased flow on demand for providing a bolus when required. Undesirable backflow of fluid is inhibited. Further, the pump of the invention can allow continuous flow of fluid when the pump chamber is being charged after manual pumping.

Claims

1. An infusion pump for providing fluid from a fluid source to the body of a patient, the infusion pump including:

- an inlet end having a fluid inlet and an outlet end having a fluid outlet;

- an inlet hub attached to the pump jacket at the inlet end;

- an outlet hub attached to the pump jacket at the outlet end; and

2. The infusion pump of claim 1, wherein the stabilizing portion is supported by a retaining clip.

3. The infusion pump of claim 2, wherein the retaining clip has a ledge abutting an end of the stabilizing portion.

4. The infusion pump of any one of claims 1 to 3, wherein a first directional valve is associated with the inlet hub and a second directional valve is associated with the outlet hub.

5. The infusion pump of any one of claims 1 to 4, which includes a bypass flow pathway from the fluid inlet to the fluid outlet, the bypass fluid pathway extending through the pump jacket while bypassing the directional valve.