Embodiments of this disclosure generally relate to compact medical infusion pumps. More particularly, embodiments of this disclosure relate to compact medical infusion pumps and related systems and methods, which can be used in or with syringe pumps, ambulatory infusion pumps, and similar medical infusion devices.
In the field of medical infusion devices including “syringe pumps” and “ambulatory infusion pumps”, typically a pre-filled fluid syringe or reservoir is mechanically driven or controlled by a microprocessor to deliver a prescribed amount or dose of a drug or fluid at a controlled rate to a patient through an infusion line fluidly connected to the syringe or reservoir. Drugs or fluids delivered to a patient by way of syringe pumps and ambulatory infusion pumps can include, but are not limited to: therapeutic agents; nutrients; drugs; medicaments such as antibiotics, blood clotting agents, and analgesics; and other fluids. The devices can be used to introduce the drugs or fluids into patients' bodies utilizing any of several routes such as, for example, intravenously, subcutaneously, arterially, or epidurally.
Examples of syringe pumps and related components are disclosed in U.S. Pat. No. 4,978,335 titled “Infusion Pump with Bar Code Input to Computer,” U.S. Pat. No. 8,182,461 titled “Syringe Pump Rapid Occlusion Detection System,” and U.S. Pat. No. 8,209,060 titled “Updating Syringe Profiles for a Syringe Pump.” Each of these patents is hereby incorporated by reference in its entirety. As used throughout this disclosure, the term “syringe pump” is intended to generally pertain to any device which acts on a syringe to controllably force fluid outwardly therefrom. As used throughout this disclosure, the term “ambulatory infusion pump” is intended to generally pertain to any device that acts on a reservoir to controllably force fluid outwardly therefrom, or otherwise regulate a flow of fluid to an ambulatory patient.
As with other technologies, throughout the evolution of infusion devices there has been increasing demand for reduction in their physical dimensions and overall sizes. However, reducing the dimensions and sizes of infusion devices has been problematic. For example, syringe pump dimensions and sizes may be limited or dictated by syringe sizes and the size of components necessary to manipulate these syringes. A typical syringe pump has a lead screw that actuates a plunger driver mechanism, which in turn acts on a plunger in the syringe to move the plunger forwardly and thereby dispense fluid outwardly from the syringe. A relatively large syringe, such as, for example, a 60 mL syringe, can require 5 inches of linear movement or travel of the plunger driver to deliver an entire volume of fluid from the syringe. Thus, the pump would need to be sufficiently large to accommodate 5 inches of linear travel of the plunger. Furthermore, when a 60 mL syringe is full, it may have an effective length of about 10 inches resulting from a syringe column or reservoir length of 5 inches plus a corresponding plunger length of about 5 inches to provide travel forwardly within the reservoir to force fluid outwardly therefrom. Thus, when a full 60 mL syringe is installed in a syringe pump, a total linear distance occupied by the combination may exceed 10 inches. Not only can an extended syringe arrangement be problematic based on the considerable length of physical space occupied on one side of the pump, but further the stability and mechanical integrity of such an extended arrangement can also be problematic.
It would therefore be useful and advantageous to provide pump mechanisms for infusion devices, such as, for example, syringe pumps, which would be compact, convenient, and provide desired stability and mechanical integrity in accurately delivering infusates to patients.
This disclosure describes novel and inventive compact medical infusion pumps and related systems and methods, which can be used in or with syringe pumps, ambulatory infusion pumps, and similar medical infusion devices. In general, medical infusion pumps having split drive mechanisms provide compact pump arrangements beneficial to medical environments of limited space, and to stable, accurate fluid delivery.
In one embodiment, a compact medical infusion pump includes a base unit and a compact pump mechanism coupled to the base unit. The base unit includes a first stationary side panel and a second stationary side panel, and a drive train assembly generally centrally located in the base unit. The compact pump mechanism includes a carriage member, a plunger driver, and a rotatable drive member. The carriage member is shaped to support a medical syringe, movable in a first linear direction relative to the base unit, and fixed to a first guide rod arm that extends through the first stationary side panel. The plunger driver is shaped to selectively engage a plunger portion of the medical syringe, moveable in a second linear direction opposite the first linear direction, and fixed to a second guide rod arm that extends through the second stationary side panel. Further, the rotatable drive member is centrally located with respect to the base unit and driven by the drive train assembly. The rotatable drive engages both the first guide rod arm and the second guide rod arm to translate the carriage member and the plunger driver in opposite directions simultaneously, or approximately so, when rotated.
In another embodiment, a compact medical syringe pump includes a base unit, a slideable carriage assembly, and a slideable plunger assembly. The slideable carriage assembly supports and selectively translates a barrel portion of a syringe relative to the base unit. The slideable plunger assembly supports and selectively translates a plunger driver member that engages a plunger portion of the syringe. Further, the slideable carriage assembly moves in an oppositely-disposed, coordinated linear manner relative to the slideable plunger assembly, so as to control dispensing of fluid from the syringe. The slideable plunger assembly moves at an equal distance and speed to the slideable carriage assembly when expanded and retracted.
A further embodiment relates to a compact medical syringe pump, including a lower stationary base unit and an upper syringe manipulation assembly. The lower stationary base unit having a first side panel and a second side panel and a drive train assembly. The upper syringe manipulation assembly disposed above the lower stationary base unit in a two-part split structure that extends and retracts in accordance with the size of a syringe supported on the assembly. The upper syringe manipulation assembly is operatively coupled in an arrangement that extends and retracts equally from the first side panel and the second side panel of the stationary housing when adjusted.
An embodiment includes a compact medical syringe pump including a base unit and a compact pump mechanism. The compact pump mechanism is coupled to the base unit and includes a first longitudinal half screw, a second longitudinal half screw, a drive nut, a plunger driver, and a carriage. The first longitudinal half screw having a first thread orientation. The second longitudinal half screw having a second thread orientation that is opposite to the first thread orientation. The first and second half screws are substantially parallel to each other and together comprise a lead screw. The drive nut has an interior surface including both the first thread orientation and the second thread orientation, the nut being rotatably engaged with the first and second half screws. The carriage is coupled to the first half screw and the plunger driver is coupled to the second half screw. Further, when the drive nut rotates, the first half screw moves in a substantially linear direction and the second half screw simultaneously, or approximately so, moves in a substantially linear direction that is opposite to movement of the first half screw, with the carriage and the plunger driver thereby moving in substantially parallel, opposite directions corresponding to movements of the first and second half screws respectively.
In an embodiment, a compact pump mechanism includes a rotatable drive member, a first track, a second track, a plunger driver, and a carriage. The first track being movably engaged with the rotatable drive member, the first track further being longitudinally moveable by rotation of the rotatable drive member. The second track being movably engaged with the rotatable drive member, the second track further being substantially parallel to the first track and longitudinally moveable by rotation of the rotatable drive member. The carriage coupled to a first guide rod arm providing the first track. The plunger driver coupled to a second guide rod arm providing the second track. When the rotatable drive member rotates, the first track moves in a substantially linear direction and the second track simultaneously, or approximately so, moves in a substantially linear direction that is opposite to movement of the first track, with the carriage and the plunger driver thereby moving in substantially parallel, opposite directions corresponding to movements of the first and second tracks respectively.
Another embodiment includes a method of compact infusate delivery. The method includes loading a syringe having a barrel portion filled with fluid infusate and a plunger portion into a syringe pump having a split drive assembly. The method further includes moving a barrel portion of a syringe in a first direction relative to a base unit of a syringe pump using the split drive assembly. The method also includes moving a plunger portion of the syringe in a second direction, opposite that of the first direction, relative to the base unit of the syringe pump using the split drive assembly, the barrel portion and the syringe portion being moved in a simultaneous, or approximately so, coordinated fashion with respect to one another. The method also includes delivering the fluid infusate with the syringe pump.
The invention may be more completely understood in consideration of the following detailed description of various embodiments of the invention in connection with the accompanying drawings, in which:
The various embodiments of the invention may be embodied in other specific forms without departing from the essential attributes thereof; therefore, the illustrated embodiments should be considered in all respects as illustrative and not restrictive.
Compact pump mechanisms described in greater detail by way of examples herein can be beneficial in numerous ways. For example, in various embodiments, a compact pump mechanism may reduce the overall size of a medical infusion pump, reduce a length of extension of a particular component from a pump housing in a particular direction, provide greater stability and mechanical integrity to components extending from a pump housing due to short cantilever length of support members, or provide a desirable centralized syringe and pump drive arrangement. As will be described by example herein, a compact pump mechanism can be achieved by effectively separating or “splitting” a medical infusion pump drive into two substantially parallel and oppositely-moving components. Accordingly, embodiments disclosed herein describing a “split drive” assembly, mechanism, or arrangement refer to embodiments in which an actuating member translates multiple non-continuous components to govern device motion.
Referring to
In such known syringe pumps, a length of linear travel of plunger 122 in barrel 112 largely depends upon a corresponding possible length of linear travel of plunger driver 120 and that the entire length of travel of plunger driver 120 occurs in one direction. Thus, the overall dimensions of known syringe pumps are typically dependent upon maximum lengths of possible travel and directions of travel of their plunger drivers. With reference to
Referring now to
Generally internal to the compact pump mechanism 201 is a rotatable drive member 230, as shown in
With reference to
When using syringe pump 20 and compact pump mechanism 201, a syringe 214 containing a desired volume of a flowable substance can be installed by way of removable placement or coupling of the syringe barrel 212 in carriage 210 (with, optionally, the barrel being secured by a clamp as aforementioned). Further, an end of a plunger 222 in the syringe 214 is removably coupled to plunger driver 220. After activation and during operation of pump 20, drive member 230 rotates which thereby causes tracks 240 and 245 to move in opposite directions. For example, when drive member 230 rotates in a clockwise (CW) direction as shown in the drawings, track 245 moves forwardly (to the left in
It is also to be appreciated and understood that mechanism 201 can be used for reversing direction of a plunger's travel such as when, for example, an occlusion is detected by the pump and the plunger is commanded to, intentionally, move backwardly or retreat a desired distance until the occlusion has been removed. In such an occurrence, drive member could be commanded to rotate in a counter-clockwise (CCW) direction as shown in
Referring now to
The central location of the drive train 280 and centralized drive movement of the rotatable drive member 230 provides a number of advantages. Known syringe pumps and similar devices generally position the motor and drive at one side of a pump housing unit in order to have a sufficiently long distance of possible plunger driver travel in one direction from a stationary or otherwise fixed carriage relative to base unit 200 to accommodate a fully extended or un-advanced syringe plunger with, for example, a filled syringe that is ready for use in dispensing a medicament contained in the syringe to a patient. Past guide rod arm members would extend a considerable distance from the drive component of the motor that was roughly equivalent to the length of such an extended or un-advanced syringe plunger.
Those of skill in the infusion arts will also appreciate that, although somewhat supported internally or structurally, typical cantilever arm lengths are significant in extension of plunger drivers in known pumps. Long cantilever arms supporting the plunger drivers of known pumps have potentially caused operational disadvantages related to, for example, stability and precision of components in those pumps. But in comparison, the presently disclosed examples of a split-drive arrangement advantageously includes two relatively short guide rod arms 226 and 228. Each of these guide rod arms 226 and 228 provide, as compared to known pumps, a much reduced cantilever arm extending from the central rotatable drive member 230 or respective stationary side panel 206 at one side to the plunger driver 220. Likewise the cantilever arm extending from the central rotatable drive member 230 or side panel 204 at one side to the end portion of the carriage 210 provides a much reduced length as comparted to known pumps. Accordingly, greater stability and accuracy can be achieved when a mechanism with reduced cantilever arms extend from the base unit 200. In some embodiments, the length of the second guide rod arm 228 extending between stationary side panel 206 of the base unit 200 and the plunger driver 220 serves as a cantilever arm having a length less than the length of the plunger portion 222 of the medical syringe 214.
Moreover, it is to be appreciated and understood that the novel and inventive arrangement of components according to subject matter hereof generally provides for approximately equal but opposite linear travel of the plunger driver 220 and carriage member 210 in a coordinated fashion from either side of the base unit 200 depending upon the size of the inserted syringe. In some embodiments, the first guide rod arm 226 extends partially beyond the first stationary side panel 204 and the second guide rod arm 228 extends partially beyond the second stationary side panel 206 when the syringe 14 is full and the plunger 222 extends outwardly from barrel 212. The disclosed arrangement does not largely extend only one portion of the pump mechanism 201 from only one side of the pump 20. Accordingly, any potential interference caused by extending features would generally be balanced and more restricted to the immediate proximity of the base unit 200 of the pump 20 itself due to centering. The pump 20 is largely a self-centered device with respect to lateral displacement of components from the sides. As compared to mechanisms of known pumps, this centering effect provides convenient and compact syringe pumps that are less likely to interfere with other devices and medical professionals attending to a patient connected to the novel and inventive pumps described by example or otherwise contemplated herein. The compactness provided can be extremely important in environments, such as emergency room settings, in which numerous devices and medical professionals are surrounding a patient and thus physical space is limited.
Accordingly, in some embodiments the compact medical syringe pump 20 includes a lower stationary base unit 201 with side panels 204 and 206 on the sides of a drive train assembly 280 that is generally centered in the base unit 201 between these side panels. Located above the base unit 201 is an upper syringe manipulation assembly 201 (or compact pump mechanism) that includes a two-part split structure that extends and retracts in accordance with the size or contained medicament volume of a syringe 214 thereby supported. The upper syringe manipulation assembly 201 is operatively coupled to extend and retract equally from the first side panel 204 and the second side panel 206 of the base unit 200 when the assembly is adjusted. Moreover, the upper syringe manipulation assembly 201 provides two separate cantilever support arms to support a syringe coupled to the two-part split structure.
Although not illustrated in
Referring now to
In this example of mechanism 901, although not specifically illustrated but similar to
Although not illustrated in
Accordingly, operation of compact infusate delivery of many of the above embodiments of a compact syringe can be carried out by an operator accordingly to a number of steps. First, a syringe having a barrel portion filled with fluid infusate and a plunger portion is loaded into a syringe pump having a split drive assembly. A barrel portion of a syringe is moved in a first direction relative to a base unit of a syringe pump using the split drive assembly. A plunger portion of the syringe is moved in a second direction, opposite that of the first direction, relative to the base unit of the syringe pump using the split drive assembly. This is done such that the barrel portion and the plunger portion are moved in a simultaneous, or approximately so, coordinated fashion with respect to one another. The fluid infusate accordingly is able to be delivered by the syringe pump.
Irrespective of a particular embodiment, it is to be appreciated and understood that compact pump mechanisms that have been described by example, or which are otherwise contemplated herein, can be characterized in that they provide movement of syringe barrels and plungers at substantially equal rates, but in linearly opposite directions. Thus, these novel and inventive compact pump mechanisms thereby provide substantially steady-state rates of delivery of flowable substances outwardly from the syringes.
It is also to be appreciated and understood that types, components, dimensions, fabrication processes, and other particulars and parameters of aforedescribed example embodiments can be substituted for others as desired, or that accessories can be added thereto. For example, the tracks could have any desired lengths provided that they are compatible with length dimensions of pumps in which they are installed.
While compact pump mechanisms have been particularly shown and described with reference to the accompanying figures and specification, it should be understood however that other modifications thereto are of course possible; and all of them are intended to be within the true spirit and scope of novel and inventive devices described herein. Thus, configurations and designs of various features could be modified or altered depending upon particular embodiments. For example, the carriage and the plunger driver could be coupled to the tracks in any order. Thus, although some examples herein have described the first tracks as being coupled to carriages and the second tracks as being coupled to plunger drivers, the first tracks could instead be coupled to plunger drivers with the second tracks therefore coupled instead to carriages. In such embodiments, the CW and CCW movements of the rotatable drive members would result in movements of the tracks, and their coupled carriages and plunger drivers, that would be analogous but opposite to the aforedescribed examples.
Compact pump mechanisms as described by example or otherwise contemplated herein could also include combinations of the aforedescribed examples of rotatable drive members having toothed sprockets or magnetic components, and tracks having slots or materials that magnetically engage the magnetic components, respectively. In those embodiments, magnetic sprockets could be coupled to slotted tracks having materials that magnetically engage the magnetic sprockets, with such compact pump mechanisms possibly being less susceptible to vibration and external forces than, for example, conventional pump mechanisms.
Furthermore, although not illustrated, compact pump mechanisms as described by example or otherwise contemplated herein could also include suitable vernier or “fine adjustment” controls for or with the rotatable drive members, tracks, drive nuts, and half screws, to possibly enable more precise movement of these components when in use.
Regardless of particular components or modes of action, it is to be appreciated and understood that compact pump mechanisms—such as have been described by example or are otherwise contemplated herein—can provide pump mechanisms for infusion devices which would be relatively compact and which would not be necessarily be defined in dimensions or sizes by syringes installed therein.
It is also to be appreciated and understood that compact pump mechanisms as have been described by example or otherwise contemplated herein could potentially be used for or with virtually any devices which control the delivery or movement of flowable substances from one location to another.
It is further to be understood that dimensioning and scaling of the drawings herein have been chosen to clearly show details of example embodiments. Thus, in some embodiments it is possible that spacing between, or orientations of, various features might be variable and visually different from those illustrated. In any event, dimensioning and scaling could vary significantly across various embodiments of compact pump mechanisms.
It is additionally to be understood in general that any suitable alternatives may be employed to provide novel and inventive compact pump mechanisms such as those that are described by example or otherwise contemplated herein.
Lastly, compositions, sizes, and strengths of various aforementioned components of compact pump mechanisms that are described by example or otherwise contemplated herein are all a matter of design choice depending upon intended uses thereof.
Accordingly, these and other various changes or modifications in form and detail may also be made, without departing from the true spirit and scope of compact pump mechanisms that may be defined by the appended claims.
It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with an enabling disclosure for implementing the exemplary embodiment or exemplary embodiments. It should be understood that various changes can be made in the function and arrangement of elements without departing from the scope of the invention as set forth in the appended claims and the legal equivalents thereof. For example, in embodiments described with a syringe-type infusion pump, it is to be understood that an ambulatory type pump could have been alternatively employed.
The embodiments above are intended to be illustrative and not limiting. Additional embodiments are within the claims. Although the present invention has been described with reference to particular embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.
Various modifications to the invention may be apparent to one of skill in the art upon reading this disclosure. For example, persons of ordinary skill in the relevant art will recognize that the various features described for the different embodiments of the invention can be suitably combined, un-combined, and re-combined with other features, alone, or in different combinations, within the spirit of the invention. Likewise, the various features described above should all be regarded as example embodiments, rather than limitations to the scope or spirit of the invention. Therefore, the above is not contemplated to limit the scope of the present invention.
Filing Document | Filing Date | Country | Kind |
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PCT/US15/63469 | 12/2/2015 | WO | 00 |
Number | Date | Country | |
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62094519 | Dec 2014 | US |