Improving fluid delivery accuracy of an infusion device

Abstract

An infusion pump control system determines, responsive to receiving a command to initiate a bolus, a delivery speed and size of the bolus, and determines an expected delivery error in an amount of the bolus based on at least one of the determined delivery speed and size of the bolus. The pump control system identifies a predetermined delivery period and fluid delivery characteristic for completing the bolus according to a predetermined fluid delivery cycle and generates an updated fluid delivery characteristic based on the expected delivery error in the amount of the bolus. The pump control system delivers the bolus by causing the fluid to be delivered through the infusion line based on the updated fluid delivery characteristic.

Description

IMPROVING FLUID DELIVERY ACCURACY OF AN INFUSION DEVICEBACKGROUND

[0001] Large volume pumps (LVPs) are capable of delivering large fluid volumes (e.g., 100 mL or more of fluid from a single container) and usually operate through peristalsis, where a rotor turning across a section of tubing causes fluid to move through the tubing through positive displacement. LVP boluses programmed at low volumes have been known to have a very high amount of variability in performance. High variability and poor performance increase patient risk, especially during the administration of life sustaining drugs and sensitive patient populations.SUMMARY

[0002] There is a need to increase the overall accuracy of LVPs, particularly in the administration of lowvolumes. Accordingly, the subject technology provides an apparatus and method for improving bolus accuracy. The subject technology adjusts bolus delivery based on the point within the fluid delivery cycle of an LVP at which the bolus delivery is initiated and predetermined fluid delivery variations.

[0003] According to various implementations, a system for improving fluid delivery accuracy of an infusion device comprises: an infusion pump configured to deliver a fluid through an infusion line loaded into the infusion pump by causing an amount of the fluid to be delivered through an infusion line according to a fluid delivery cycle; and a control unit configured to, prior to delivering the fluid: receive a command for the infusion pump to initiate a bolus of the fluid; determine, based on receiving the command and before initiating the bolus, a delivery speed and size of the bolus; determine an expected delivery error in an amount of the bolus based on at least one of the determined delivery speed and size of the bolus; identify a predetermined delivery period and a fluid delivery characteristic for completing the bolus according to the fluid delivery cycle; generate an updated fluid delivery characteristic for the identified fluid delivery characteristic based on the identified predetermined delivery period and the identified expected error in the amount of the bolus; and configure the infusion pump to deliver the bolus by causing the fluid to be delivered through the infusion line according to the updated fluid delivery characteristic and an updated fluid delivery cycle. Other aspects include corresponding apparatus (e.g., an infusion device), methods and computer program products for implementation of the corresponding system and its features.

[0004] According to various implementations, a method for improving fluid delivery accuracy of an infusion device comprises: operating an infusion pump configured to deliver a fluid through an infusion line loaded into the infusion pump by causing an amount of the fluid to be delivered through an infusion line according to a fluid delivery cycle; and prior to delivering the fluid: receiving a command for the infusion pump to initiate a bolus of the fluid; determining, based on receiving the command and before initiating the bolus, a delivery speed and size of the bolus; determining a magnitude of an expected delivery error in an amount of the bolus based on at least one of the determined delivery speed and size of the bolus; identifying a predetermined delivery period and a fluid delivery characteristic for completing the bolus according to the fluid delivery cycle; generating an updated fluid delivery characteristic for the identified fluid delivery characteristic based on the identified predetermined delivery period and the identified expected error in the amount of the bolus; and configuring the infusion pump to deliver the bolus by causing the fluid to be delivered through the infusion line according to the updated fluid delivery characteristic and an updated fluid delivery cycle. Other aspects include corresponding apparatus (e.g., an infusion device), systems and computer program products for implementation of the corresponding method and its features.

[0005] It is understood that other configurations of the subject technology will become readily apparent to those skilled in the art from the following detailed description, wherein various configurations of the subject technology are shown and described by way of illustration. As will be realized, the subject technology is capable of other and different configurations and its several details are capable of modification in various other respects, all without departing from the scope of the subject technology. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not as restrictive.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] For a better understanding of the various described implementations, reference should be made to the Description of Implementations below, in conjunction with the following drawings. Like reference numerals refer to corresponding parts throughout the figures and description.

[0007] FIG. 1A depicts a perspective view of an example infusion device showing an infusion set in place within the infusion device, according to various aspects of the subject technology.

[0008] FIG. IB depicts an example patient care unit shown, according to various aspects of the subject technology.

[0009] FIG. 2 depicts an example pumping mechanism of an infusion pump, according to various aspects of the subject technology.

[0010] FIG. 3 depicts an example cam phase diagram corresponding to a fluid delivery cycle of an infusion pump, according to various aspects of the subject technology.

[0011] FIG. 4 depicts a first example profile of bolus volume error by flow rate for a given bolus volume, according to various aspects of the subject technology.

[0012] FIG. 5 depicts an example process for improving fluid delivery accuracy of an infusion device, according to aspects of the subject technology.

[0013] FIG. 6 is a conceptual diagram illustrating an example electronic system for improving fluid delivery accuracy of an infusion device, according to aspects of the subject technology.DESCRIPTION

[0014] Reference will now be made to implementations, examples of which are illustrated in the accompanying drawings. In the following description, numerous specific details are set forth, in order to provide an understanding of the various described implementations. However, it will be apparent to one of ordinary skill in the art that the various described implementations may be practiced without these specific details. In other instances, well- known methods, procedures, components, circuits, and networks have not been described in detail so as not to unnecessarily obscure aspects of the implementations.

[0015] According to various implementations of the subject technology, a fluid tubing is loaded in an infusion pump and primed with a fluid. During fluid delivery, upper and lower occluder elements of an infusion pump are activated to press against the fluid tubing to block and isolate the fluid in an upstream portion of the tubing from a downstream portion of thetubing. While flow within the fluid tubing is blocked by the occluder elements, a pumping element of the infusion pump is activated to compress an intermediate portion of the tubing, between the downstream portion and the upstream portion, to cause a pressure increase within the fluid tubing. The lower occluder is opened and the fluid flows downstream. The foregoing cycle repeats to continuously pump a fluid through the fluid tubing.

[0016] It has been found that, as a volume of fluid delivered by a large volume pump (LVP) decreases, the potential for error increases and, conversely, as a volume of fluid delivered by the LVP increases the potential for error decreases, and that these variances are due, at least in part, to the current state of the pump’s pumping mechanism. Additionally, for low volume boluses, as the delivery speed — or flow rate — of the bolus increases, the amount of error in the form of overshoot also increases.

[0017] As will be described further, the subject technology adjusts a characteristic of the pump’s delivery period (e.g., the administration rate during a predetermined duration, the number motor steps performed for a programmed delivery, rotations or partial rotations of the cam involved in the bolus delivery, and / or length of a predetermined fluid delivery period) to account for estimated discrepancies in fluid delivery over a given cycle. When correcting for potential fluid delivery overshoot for a bolus, the characteristic of the fluid delivery period for delivering the bolus is adjusted and the bolus delivered according to the updated characteristic.FIG. 1 A depicts a perspective view of an example infusion device showing an infusion set in place within the infusion device, according to various aspects of the subject technology. An infusion system for parenteral infusion of a medical fluid to a patient comprises a pump unit, a major part of which comprises a housing which accommodates, in manner known per se, a cam system (not shown) controlling a plurality of fingers of a pumping mechanism, an electric motor and associated gearing, driving said cam mechanism, and further accommodates electronic control and processing circuitry for controlling such motor and processing signals from pressure sensors etc. provided on the unit. The pump unit, as shown, may also comprise an electronically operated display, an alarm light, an input keyboard or other manually operated controls, all in manner known per se.

[0018] As shown in FIG. 1A, an infusion pump 10 is shown in perspective view with the front door 50 open, showing the upstream fluid line 30 (e.g., portion between fluid container and the infusion pump 30) and downstream fluid line 31 (e.g., portion between the infusionpump 31 and a patient) in operative engagement with the infusion pump 10. The infusion pump 10 directly acts on a tube 66 that connects the upstream fluid line 30 to the downstream fluid line 31 to form a continuous fluid conduit, extending from a respective fluid supply to a patient, through which fluid is acted upon by the pump to move fluid downstream to the patient. Specifically, a pumping mechanism 70 acts as the flow control device of the pump to move fluid though the conduit. The depicted references 30, 31, 66 may be used to describe herein portions of one continuous fluid line or, in some implementations, may individually describe portions that are fluidly connected together to form a continuous fluid line. The upstream and downstream fluid lines and / or tube 30, 31, 66 may also be coupled to a pump cassette or cartridge that is configured to be coupled to the pump 10.

[0019] As shown in FIG. 1 A, the face plate 50 which may be opened to reveal the internal loading mechanism for an infusion set. Within the housing of the infusion device (e.g., behind the door or face place), the infusion device includes a pumping segment including a group of serially-aligned pumping elements configured to compress an elongated compressible channel of an infusion set 66, when loaded within the pumping segment. The pumping segment includes a group of serially-aligned pumping elements (e.g., occluders and / or pumping finger(s)) configured to compress the elongated compressible channel (e.g., an IV tubing segment) loaded within the pumping segment.

[0020] The infusion set includes an intermediate section of the resiliently compressible tubing 66, for example of silicone rubber and, in some implementations, upper and / or lower fittings which each tubing section may be connected respectively with a respective upper line 30 and with the lower line 31. In use, each upper line 30 extends upwardly to a source of the medical fluid to be administered whilst the lower line 31 extends from the infusion pump to an infusion needle or the like inserted into the patient. In use, the infusion set 66 is extended across the face or deck of the pump unit so that its fittings (not labeled) are received in respective brackets respectively and so that the tubing segment extends over a pumping mechanism. In the depicted example, the pumping mechanism includes a four finger pump assembly 72, 74, 76, 78. In the depicted example, the infusion set is fitted in place in this fashion whilst the door 50 is in the open position. After the infusion line has been so fitted, the door 50 may be moved to the closed position and is secured by a catch 52 which may include a lever mounted on the outer edge of the door.

[0021] The four finger pump assembly 72, 74, 76, 78 includes respective fingers that are moveable by a cam system inwards and outwards from the face or deck of the pump to compress a respective tubing segment against a counter surface or anvil to propel fluid within the infusion line. In order to make it easier to maintain sterile conditions, these fingers may be covered by a thin flexible membrane, (not shown), sealed at its edges with respect to the deck. The fingers of the pump assembly periodically press the flexible resilient tubing against the counter surface which may be configured on an opposite side, for example, on an inner portion of the door 50.

[0022] The type of pumping mechanism may vary, including the number of fingers in the pumping mechanism. In the depicted example, the pumping mechanism includes an upstream occluding element or finger 72, a primary pumping element or finger 74, a downstream occluding element or finger 76, and a secondary pumping element or finger 78. The pumping mechanism (and mechanisms used in other linear peristaltic pumps) operate by sequentially pressing on a segment of the fluid conduit by means of the cam-following pumping elements (e.g., pumping fingers and valve fingers) 72, 74, 76, and 78, which in the depicted example make a four finger pump assembly. Each element may be sequentially activated by a respective cam lobe on a camshaft to apply a downward compression against tubing 66, to move the fluid in the tubing 66 downstream. Intermediate pumping mechanism 74 may include multiple intermediate elements or fingers (not shown) that sequentially activate according to positioning of the cam lobes. In some implementations, the pressure is applied in sequential locations of the conduit, beginning at the upstream end of the pumping mechanism, and working toward the downstream end. At least one finger is always pressing hard enough to occlude the conduit. As a practical matter, one finger does not retract from occluding the tubing until the next one in sequence has already occluded the tubing; thus, at no time is there a direct fluid path from the fluid supply to the patient. The operation of peristaltic pumps including four finger pumps is well known to those skilled in the art and no further operational details are provided here.

[0023] An upstream pressure sensor 80 may also be included in the pump 10. The upstream pressure sensor may be mounted to pumping mechanism 70 or located adjacent and upstream in relation to the pumping mechanism 70 between a fluid supply and the pumping mechanism 70, so that the connection of the correct fluid supply with the correct pump may be verified before any fluid is pumped to the patient. A downstream pressure sensor 82 is also included in the example infusion pump 10 at a downstream location with respect to the pumpingmechanism, that is, at a location between the patient and the flow control device, so that the connection of the correct fluid supply with the correct pump may be verified before any fluid is pumped to the patient. Downstream pressure sensor 82 may be used to detect a pressure change adjacent to occluder 76 and / or downstream finger 78, to determine whether these elements are functioning properly.

[0024] FIG. IB depicts an example patient care unit 12 shown, according to various aspects of the subject technology. FIG. IB shows two functional infusion pumps 10 (e.g., “infusion pump modules”) mounted at either side of a main frame infusion controller 14, and the displays and control keys of each, with the main frame infusion controller 14 being capable of programming both infusion pumps. The infusion device includes a door 5a and a handle 5b that operates to lock the door in a closed position for operation and to unlock and open the door for access to the internal pumping and sensing mechanisms and to load administration sets for the pump. When the door 5a is open, the tube can be connected with the pump 10. When the door 5a is closed, the tube is brought into operating engagement with the pumping mechanism, the upstream and downstream pressure sensors, and the other equipment of the pump. A display 5c, such as an LED display, is located in plain view on the door in this embodiment and may be used to visually communicate various information relevant to the pump 10, such as alert indications (e.g., alarm messages). Control keys 5e-h may exist for programming and controlling operations of the infusion pump as desired. In some implementations, the control keys may be presented as interactive elements on the display 5c (e.g., touchscreen display). The main frame and / or functional module may also include audio alert equipment in the form of a speaker (not shown).

[0025] The main frame infusion controller 14 of the patient care unit 12 includes a display 6a for visually communicating various information, such as the operating parameters of a connected pump and alert indications and alert messages, and control keys 6b and 6c for selecting and / or setting control parameters and / or options for controlling the patient care unit 12 and connected modules. The main frame infusion controller 14 may also include a speaker to provide audible alerts. In some implementations, the display 6a may be implemented as a touchscreen display. In such implementations, the control keys 6b may be omitted or reduced in number by providing corresponding interactive elements via a graphical user interface presented via the display 6a. In some implementations, each control key 6b (or 6c) may select a corresponding option displayed in display 6b.

[0026] The main frame infusion controller 14 may include a communications system (not shown) with which the main frame infusion controller 14 may communicate with external equipment such as a medical facility server or other computer and with a portable processor, such as a handheld communication device or a laptop-type of computer, or other information device that a clinician may have to transfer information as well as to download drug libraries to a functional module 10. The communication module may be used to transfer access and interaction information for clinicians encountering the main frame infusion controller or device coupled therewith (e.g., pump 10 or bar code scanner). The communications system may include one or more of a radio frequency (RF) system, an optical system such as infrared, a BLUETOOTH™ system, or other wired or wireless system. The bar code scanner and communications system may alternatively be included integrally with the infusion pump 10, such as in cases where a main frame infusion controller is not used, or in addition to one with the main frame infusion controller 14. Further, information input devices need not be hardwired to medical instruments, information may be transferred through a wireless connection as well. Additionally, other types of modules may be connected to the pump modules or to the main frame infusion controller such as a syringe pump module, patient controlled analgesic module, end tidal CO2 monitoring module, oximeter monitoring module, or the like.

[0027] FIG. 2 depicts an example pumping mechanism 120 of an infusion device 10 including two occluder valves 100, 110 (e.g., pumping elements 72, 76), according to various aspects of the subject technology. A typical medical pump for IV infusion delivery has two occluders, a first occluder 100 located upstream and a second occluder 110 located downstream, with a plunger 120 (e.g., pumping element 74) in between. The occluders and plunger coordinate with each other in programmable, sequential steps, controlled by a cam shaft to have two phases: 1) a filling phase, and 2) a delivery phase. The occluders move fluid in a tubing 103 by sequentially compressing the tubing, thereby causing a flow in a direction 104 according to the particular compression sequence of the occluders.

[0028] During the medication infusion process, in the filling phase, the upstream occluder 100 lifts to suck the medication into the tubing segment, which creates a pause, followed by the delivery phase to push the fluid out. These sequences can repeat through multiple cycles. To specify, when the plunger of a single plunger / tubing design is lifted from the tubing segment during the filling phase, there will be a disruption in the continuous infusion process.

[0029] FIG. 3 depicts an example cam phase diagram corresponding to a fluid delivery cycle of an infusion pump, according to various aspects of the subject technology. Each row depicted in FIG. 5 corresponds to a pumping element 72, 74, 76, 78, and illustrates an example pumping function of the element according to a complete cam rotation (360°). That is which pumping elements are closing (compressing the tube) and which elements are opening, thereby creating an aspiration phase and a dispensing phase.

[0030] In the depicted example, initially, from 0° to 90°, the upper occluder 72 is open, while the lower occluder remains closed. The upper occluder 72 completes closing at about 120°; however, the fluid tubing may be sufficiently compressed to stop aspiration of the fluid at about 110°. The lower occluder remains closed until the cam reaches 140°. While the upper occluder 72 is open — until it begins to close at about 90° — the upper finger 74 is aspirating. The upper occluder closes between 90-120°, and the lower occluder begins to open at 140°. At this point, the lower finger will begin to deliver the fluid. In the depicted example, delivery begins at about 145°, with about 5° rotation accounting for the time to decompress the tubing.

[0031] FIG. 4 depicts a first example profile of bolus volume error by flow rate for a given bolus volume, according to various aspects of the subject technology. The subject technology characterizes a pump (or type of pump) over its fluid delivery cycle, to identify variations in delivery from a linear delivery. As an example, under-delivery may occur during a refill phase and over-delivery may occur during a delivery phase, or vice versa. Characterization of the pump may occur during manufacturing (e.g., for the type of pump generally) or may occur in real-time based on flow monitoring and machine learning principles. In some implementations, characterization (or profiling) the pump identifies an increase in fluid delivery — or overdelivery — as the flow rate increases.

[0032] According to various implementations, bolus accuracy (in terms of bolus volume error) may be characterized by testing the mean bolus accuracy performance across a range of programmable flow rates for a given volume. In the depicted example, a regression equation is used to model the mean error over delivery, across a range of programmable flow rates, and the magnitude of the delivery error is plotted by flow rate. As illustrated, the mean bolus volume error is found to increase commensurate with increasing flow rate.

[0033] While the depicted example is for a first predetermined bolus amount of 0.1 mL, it is understood that smaller bolus volumes may yield larger volume error. For the purpose ofthe disclosure, expected delivery error is characterized as a percentage of bolus volume, or volume error; however, it is understood that the expected delivery error magnitude may be characterized as fixed units (e.g., in mL). According to various implementations, a delivery error determined for a given flow rate and / or bolus volume during a manufacturing process, and the error stored in a lookup table by flow rate and / or bolus volume. The lookup table may then be indexed by bolus amount and / or flow rate during a testing process to determine the accuracy of the device, or during a patient therapy to inform bolus adjustments for accurate delivery of a medication.

[0034] According to various implementations, the infusion device is mechanically and / or programmatically configured to deliver a measured volume per mechanical revolution (VPMR) of the cam. The volume to be infused (VTBI) is translated into steps (or half steps) of the pump’s motor to control the amount of fluid delivered. Increasing the number of steps increases the amount of fluid delivered. The system may use VPMR to translate a number of motor steps to the bolus VTBI and vice versa.

[0035] In some implementations, the pump software keeps track of the number of steps the motor has traveled and adds a correction based on the pump’s delivery profile (and variations). In some implementations, the software determines a motor duration (e.g., in degrees or time) to perform the bolus based on flow rate and / or bolus size. In some implementations, the number of cycles or sub-cycles (measured in, e.g., degrees or steps) may be adjusted.

[0036] Responsive to receiving a command to initiate a bolus, the delivery speed and size of the bolus is determined, and an expected delivery error in an amount of the bolus based on at least one of the determined delivery speed and size of the bolus is calculated. The infusion device’s control system identifies a predetermined delivery period for completing the bolus of the bolus size under normal conditions. A characteristic of the identified delivery period is then adjusted based on the expected delivery error and the bolus is delivered according to the adjusted characteristic.

[0037] In some implementations, the pump software determines a cumulative fluid delivery error for a fixed bolus amount (e.g., 0.10 mL), and then estimates a number of motor steps or cam rotations corresponding to a fluid amount corresponding to the magnitude of the error (e.g., 0.01 mL at 10% error). The number of motor steps or cam rotations for delivering the fixed bolus amount may then be adjusted by the amount corresponding to the error. Forexample, a 10% error may yield an overshoot of 0.01 mL for a 0.1 mL bolus, resulting in the potential of a 1.1 mL bolus being delivered. The number of motor steps or cam rotations may then be reduced accordingly by the error so that an accurate bolus amount is delivered. In some implementations, the software may determine the adjustment by indexing a table based on the bolus size (e.g., volume) and / or the flow rate, and increase or decrease the number of cam rotations or motor steps by the adjustment returned from the table.

[0038] FIG. 5 depicts an example process 500 for testing an infusion device, according to aspects of the subject technology. For explanatory purposes, the various blocks of example process 500 are described herein with reference to FIGS. 1 through 4, and the components and / or processes described herein. The one or more of the blocks of process 500 may be implemented, for example, by one or more computing devices including, for example, within infusion device 12. In some implementations, one or more of the blocks may be implemented based on one or more machine learning algorithms. In some implementations, one or more of the blocks may be implemented apart from other blocks, and by one or more different processors or devices. Further for explanatory purposes, the blocks of example process 500 are described as occurring in serial, or linearly. However, multiple blocks of example process 500 may occur in parallel. In addition, the blocks of example process 500 need not be performed in the order shown and / or one or more of the blocks of example process 500 need not be performed.

[0039] In the depicted example, the infusion pump 10 is configured to deliver a fluid through an infusion line loaded into the infusion pump by causing an amount of the fluid to be delivered through an infusion line according to a fluid delivery cycle. At least one occluder element of an infusion pump 10 is activated to compress the fluid tubing filled with a fluid, to move the fluid in an upstream portion of the fluid tubing (e.g., in a fluid container upstream of the pump) to a downstream portion of the tubing, downstream of the infusion pump 10. As described previously, the infusion pump 10 includes or is associated with a control unit. The control unit may be part of a patient care unit 12 or may be implemented as a processing component within the infusion pump 10.

[0040] The control unit receives a command for the infusion pump to initiate a bolus of the fluid (502). The bolus may be any amount, including less than 1 mL or more than 100 mL. According to various implementations, the pump software is programmed to deliver a fixed amount of fluid during each cycle. For example, the pump may be configured to delivery 0.17mL per fluid delivery cycle (e.g., each rotation of the cam). This amount may be adjusted based on the type of fluid or type of tubing used to delivery the fluid. For example, heavier fluids and / or heavier tubing may require a longer fluid delivery period to deliver the same amount, and the predetermined amount delivered each cycle may be stored in a memory, indexed by the fluid type and / or tubing type.

[0041] The control unit, based on (e.g., responsive to) receiving the and before initiating the bolus, determines delivery speed and / or size of the bolus (504). According to various implementations, the control unit receives an input of the delivery speed and size of the bolus with or in connection with the command. The input may be a user input received via input control keys 5e-h or 6b or 6c, or via a touch screen input 6a In some implementations, the input may be received as an automated programming request (APR) transmitted to the control unit from a server (e.g., to auto-program the infusion).

[0042] Optionally, the control unit determines whether a precondition is satisfied before making any adjustment to the bolus. According to various implementations, the precondition includes determining that at least one of the delivery speed and size of the bolus satisfies a predetermined threshold (506). In this regard, the control unit may determine that the delivery speed of the bolus is greater than a predetermined delivery speed and / or the size of the bolus is less than a predetermined bolus size. For example, the control unit may require that the bolus amount (e.g., volume) be equal to or below a predetermined amount of fluid (e.g., 0.1ml). In some implementations, the control unit requires the delivery speed to be above a certain flow rate (e.g., greater than or equal to 5 mL per hour). Either or both conditions may be required to satisfy the precondition. If the precondition is not satisfied then the process ends, and the control unit performs the programmed bolus without adjustment or alteration. If the precondition is satisfied then the process continues to determine an adjustment.

[0043] The control unit identifies a predetermined delivery period and a fluid delivery characteristic for completing the bolus according to the fluid delivery cycle (508). That is, a period for completing the bolus under default or nominal conditions (e.g., not accounting for potential delivery error, as discussed below) is determined. In some implementations, the predetermined delivery period includes a predetermined motor duration. The fluid delivery characteristic may include a motor speed or a flow rate. In some implementations, the predetermined delivery period and / or fluid delivery characteristic includes a predetermined number of motor steps. For example, the characteristic may include the number of steps, whilethe number of steps also defines the duration. In some implementations, the predetermined delivery period and / or fluid delivery characteristic includes an amount of cam rotation, wherein a fluid delivery cycle corresponds to or is synonymous with a complete rotation of a cam responsible for operating a peristaltic pumping mechanism and the delivery period for a given fixed bolus may correspond to one or more rotations and / or partial rotations of the cam, which may be determined as a fixed number of degrees (e.g., 180, 360, 450, 540, etc.). According to various implementations, the control unit may determine the predetermined delivery period and / or fluid delivery characteristic by indexing a database (e.g., a lookup table) by the received bolus size and obtaining the given duration from the table.

[0044] The control unit determines an expected delivery error in an amount of the bolus based on at least one of the determined delivery speed and size of the bolus (510). The expected delivery error corresponds to an amount of fluid that is over or under the amount of the programmed bolus. For example, for a programmed bolus of 0.1 mL, the control unit may determine an over-infusion of 0.01 mL. That is, if not corrected, the programmed bolus could result in a bolus of 0.11 mL. According to various implementations, the delivery error can be retrieved from a database (e.g., a lookup table) by the bolus size and / or the desired flow rate (e.g., received by the control unit in step 504). In various implementations, the expected delivery error may be a volume (e.g., 0.01 mL).

[0045] The expected delivery error may be translated to and / or expressed in units corresponding to the determined delivery period. That is, the delivery error may be returned from the database as a duration (e.g., seconds or milliseconds, etc.) for delivering an amount of the fluid corresponding to the error. The delivery error may be returned from the database as, or converted to, a number of motor steps or number of cam rotations and / or partial rotations or degrees of rotation.

[0046] The control unit generates an updated fluid delivery characteristic for the identified fluid delivery characteristic based on the identified predetermined delivery period and the identified expected error in the amount of the bolus (512). In some implementations, updating the fluid delivery characteristic includes changing a flow rate (or the rate of fluid administration) during the fluid delivery period. In this regard, the control unit may reduce the number of motor steps while keeping the overall duration of the bolus administration constant, which may include adjusting the motor to a slower motor rotation and reduced flow rate.

[0047] In some implementations, the fluid delivery characteristic includes a time-based duration of the delivery (e.g., motor duration) which is reduced by a time-based duration associated with the delivery error. Where the expected delivery error is expressed as motor steps, generating the updated fluid delivery characteristic of the fluid delivery period may include estimating a number of motor steps to complete the bolus and reducing the estimated number of motor steps by a number of motor steps (or half steps) corresponding to the delivery error. As will be described further, the reduced number of motor steps may then be performed over the predetermined delivery duration. Adjustment (e.g., reduction) of the motor duration may also adjust (e.g., reduce) a cam cycle. When the expected delivery error is expressed as cam rotation or degrees of cam rotation, the control unit may adjust the cam rotation determined for completing the bolus by a cam rotation associated with the expected delivery error. A predetermined adjustment to cam rotation does not necessarily equate to a predetermined adjust in motor steps, and vice versa. In some implementations, the time-based duration of the delivery or motor duration may be reduced by increasing the speed of the motor (e.g., accelerating the motor).

[0048] According to various implementations, the predetermined delivery period is reduced by an amount inversely proportional to the determined delivery speed of the bolus. In this regard, the predetermined delivery period may be reduced more (e.g., by a amount) when the determined delivery speed is a first flow rate (e.g., 0.1 mL) than (e.g., by a second amount) when the determined delivery speed is a second flow rate that is greater than the first flow rate (e.g., 0.2 mL). An updated fluid delivery period and / or flow rate may be different than a delivery period or flow rate based on a function absent the delivery error. As described previously, the control unit may first determine a default fluid delivery period and / or flow rate for the given bolus and then modify that fluid delivery period and / or flow rate based on the period associated with the expected delivery error (e.g., flow rate, in time, motor steps, or cam rotation / degrees).

[0049] In some implementations, the control unit may index the table by the starting position and (in some implementations) the volume of the bolus, and the table may return the number of fluid delivery cycles (which may be less than a whole number) to perform the bolus. The control unit may then determine the ending position in the current cycle or future cycle at which the bolus will be completed. As an example, the control unit may estimate a number of cam rotations to perform the bolus, where the estimated number of cam rotations includes atleast one partial rotation (e.g., 1.02 cam rotations), which may then be added to the current cam angle to determine the cam angle at which the bolus will be completed. When the cam is rotated, the pump may continue to rotate the cam until the newly determined ending cam position / angle is reached. In some implementations, the control unit determines a number of default motor steps to complete the bolus, and increases or reduces that number based on the starting position.

[0050] In some implementations, the estimation is further based on a function of the size of the bolus and / or the speed at which the bolus is to be delivered (e.g., flow rate in mL / hr). During the setup of the infusion therapy, a clinician may cause the pump to receive the size (e.g., volume) of the bolus and / or the flow rate. Entry of the bolus parameters such as volume and / or flow rate may be received via input control keys 5e-h or 6b or 6c, or via a touch screen input 6a. In some implementations, bolus parameters are received from a remote device or computing system. For example, the clinician may use a terminal to cause an information server to send an automated programming request directly to the pump to program the pump with the bolus parameters, or may use a mobile device or other terminal operably connected to the pump to enter the parameters. In implementations where the previously described lookup table is indexed by the size of the bolus and / or the received flow rate, the control unit may provide the bolus size and / or flow rate to the database. In some implementations, the size and flow rate may be provided to a separate table (or database), and a modification of the previously described adjustment may be determined based on the size and / or flow rate.

[0051] The control unit delivers the bolus by causing the fluid to be delivered through the infusion line according to the updated fluid delivery characteristic (514). In this regard, the infusion pump may be configured to deliver the bolus by causing the fluid to be delivered through the infusion line according to the updated fluid delivery characteristic and an updated fluid delivery cycle. The updated characteristic of the fluid delivery period may result in the updated fluid delivery cycle. For example, the number of motor steps and / or cam rotations may be different, yet the duration may remain the same as the identified predetermined delivery period. The pump begins to pump the fluid according to the updated fluid delivery cycle, which may be a number of cam cycles or degrees, motor steps, or a motor duration.

[0052] In some implementations, the predetermined motor speed and / or duration for the bolus is adjusted by a speed and / or duration for delivering an amount of the fluid corresponding to the expected delivery error. In some implementations, the predetermined delivery period isa number of motor steps to complete the bolus and the control unit reduces the estimated number of motor steps corresponding to the delivery error (e.g., number of steps to delivery the error amount), and delivers the bolus by performing the reduced number of motor steps, for example, within the same duration of time (thus reducing the delivery rate during the delivery period). In some implementations, the control unit adjusts the amount of cam rotation (e.g., in degrees) based on at least a portion of the cam rotation associated with the expected delivery error, and causes the cam to rotate according to the adjusted cam cycle (e.g., adjusting the end position of the cam cycle at which the bolus will be terminated). For example, the amount of cam rotation may be adjusted (e.g., reduced) for the same fluid delivery duration estimated for the bolus (before adjusting for the error). Accordingly, when the error is expected to cause an over-infusion of the fluid, the foregoing adjustments to the predetermined delivery period are made to prevent the over-infusion of the fluid.

[0053] Many of the above-described devices, systems and methods, may also be implemented as software processes that are specified as a set of instructions recorded on a computer readable storage medium (also referred to as computer readable medium), and may be executed automatically (e.g., without user intervention). When these instructions are executed by one or more processing unit(s) (e.g., one or more processors, cores of processors, or other processing units), they cause the processing unit(s) to perform the actions indicated in the instructions. Examples of computer readable media include, but are not limited to, CD- ROMs, flash drives, RAM chips, hard drives, EPROMs, etc. The computer readable media does not include carrier waves and electronic signals passing wirelessly or over wired connections.

[0054] The term “software” is meant to include, where appropriate, firmware residing in read-only memory or applications stored in magnetic storage, which can be read into memory for processing by a processor. Also, in some implementations, multiple software aspects of the subject disclosure can be implemented as sub-parts of a larger program while remaining distinct software aspects of the subject disclosure. In some implementations, multiple software aspects can also be implemented as separate programs. Finally, any combination of separate programs that together implement a software aspect described here is within the scope of the subject disclosure. In some implementations, the software programs, when installed to operate on one or more electronic systems, define one or more specific machine implementations that execute and perform the operations of the software programs.

[0055] A computer program (also known as a program, software, software application, script, or code) can be written in any form of programming language, including compiled or interpreted languages, declarative or procedural languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, object, or other unit suitable for use in a computing environment. A computer program may, but need not, correspond to a file in a file system. A program can be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub programs, or portions of code). A computer program can be deployed to be executed on one computer or on multiple computers that are located at one site or distributed across multiple sites and interconnected by a communication network.

[0056] FIG. 6 is a conceptual diagram illustrating an example electronic system 600 for improving fluid delivery accuracy of an infusion device, according to aspects of the subject technology. Electronic system 600 may be representative of a control unit and / or computing device for execution of software associated with one or more components and processes provided by FIGS. 1 through 5 (e.g., pump software), including but not limited to infusion pump 10 (e.g., a processing system of controller 14 or within infusion pump 10). Electronic system 600 may be representative of a device used in connection or combination with the disclosure regarding FIGS. 1 through 5. In this regard, electronic system 600 may be a device connected to the infusion device 10, for example, to activate the occluders and / or pumping fingers, the cam 142, or to monitor or control same. For example, system 600 may be representative of a personal computer or a mobile device such as a smartphone, tablet computer, laptop, personal digital assistant (PDA), an augmented reality device, a wearable such as a watch or band or glasses, or combination thereof, or other touch screen or television with one or more processors embedded therein or coupled thereto, or any other sort of computer-related electronic device having network connectivity specifically configured to implement one or more of the features described.

[0057] Electronic system 600 may include various types of computer readable media and interfaces for various other types of computer readable media. In the depicted example, electronic system 600 includes a bus 608, processing unit(s) 612, a system memory 604, a readonly memory (ROM) 610, a permanent storage device 602, an input device interface 614, an output device interface 606, and one or more network interfaces 616. In some implementations,electronic system 600 may include or be integrated with other computing devices or circuitry for operation of the various components and processes previously described.

[0058] Bus 608 collectively represents all system, peripheral, and chipset buses that communicatively connect the numerous internal devices of electronic system 600. For instance, bus 608 communicatively connects processing unit(s) 612 with ROM 610, system memory 604, and permanent storage device 602.

[0059] From these various memory units, processing unit(s) 612 retrieves specific instructions to execute and data to process, in order to execute the processes of the subject disclosure. The processing unit(s) can be a single processor or a multi-core processor in different implementations.

[0060] ROM 610 stores static data and instructions that are needed by processing unit(s) 612 and other modules of the electronic system. Permanent storage device 602, on the other hand, is a read-and-write memory device. This device is a non-volatile memory unit that stores instructions and data even when electronic system 600 is off. Some implementations of the subject disclosure use a mass-storage device (such as a magnetic or optical disk and its corresponding disk drive) as permanent storage device 602.

[0061] Other implementations use a removable storage device (such as a floppy disk, flash drive, and its corresponding disk drive) as permanent storage device 602. Like permanent storage device 602, system memory 604 is a read-and-write memory device. However, unlike storage device 602, system memory 604 is a volatile read-and-write memory, such as random access memory. System memory 604 stores some of the instructions and data that the processor needs at runtime. In some implementations, the processes of the subject disclosure are stored in system memory 604, permanent storage device 602, and / or ROM 610. From these various memory units, processing unit(s) 612 retrieves instructions to execute and data to process, in order to execute the processes of some implementations.

[0062] Bus 608 also connects to input and output device interfaces 614 and 606. Input device interface 614 enables the user to communicate information and select commands to the electronic system. Input devices used with input device interface 614 include, e.g., alphanumeric keyboards and pointing devices (also called “cursor control devices”). Output device interfaces 606 enables, e.g., the display of images generated by the electronic system 600. Output devices used with output device interface 606 include, e.g., printers and displaydevices, such as cathode ray tubes (CRT) or liquid crystal displays (LCD). Some implementations include devices such as a touchscreen that functions as both input and output devices.

[0063] Also, as shown in FIG. 6, bus 608 also couples electronic system 600 to a network (not shown) through network interfaces 616. Network interfaces 616 may include, e.g., a wireless access point (e.g., Bluetooth or WiFi) or radio circuitry for connecting to a wireless access point. Network interfaces 616 may also include hardware (e.g., Ethernet hardware) for connecting the computer to a part of a network of computers such as a local area network (“LAN”), a wide area network (“WAN”), wireless LAN, a personal area network (“PAN”), or an Intranet, or a network of networks, such as the Internet. Any or all components of electronic system 600 can be used in conjunction with the subject disclosure.

[0064] These functions described above can be implemented in computer software, firmware, or hardware. The techniques can be implemented using one or more computer program products. Programmable processors and computers can be included in or packaged as mobile devices. The processes and logic flows can be performed by one or more programmable processors and by one or more programmable logic circuitry. General and special purpose computing devices and storage devices can be interconnected through communication networks.

[0065] Some implementations include electronic components, such as microprocessors, storage and memory that store computer program instructions in a machine-readable or computer-readable medium (also referred to as computer-readable storage media, machine- readable media, or machine-readable storage media). Some examples of such computer- readable media include RAM, ROM, read-only compact discs (CD-ROM), recordable compact discs (CD-R), rewritable compact discs (CD-RW), read-only digital versatile discs (e.g., DVD- ROM, dual-layer DVD-ROM), a variety of recordable / rewritable DVDs (e.g., DVD-RAM, DVD-RW, DVD+RW, etc.), flash memory (e.g., SD cards, mini-SD cards, micro-SD cards, etc.), magnetic and / or solid state hard drives, read-only and recordable Blu-Ray® discs, ultra density optical discs, any other optical or magnetic media, and floppy disks. The computer- readable media can store a computer program that is executable by at least one processing unit and includes sets of specific instructions for performing various operations described herein. Examples of computer programs or computer code include machine code, such as is producedby a compiler, and files including higher-level code that are executed by a computer, an electronic component, or a microprocessor using an interpreter.

[0066] While the above discussion primarily refers to microprocessor or multi-core processors that execute software, some implementations are performed by one or more integrated circuits, such as application specific integrated circuits (ASICs) or field programmable gate arrays (FPGAs) specifically configured with one or more of the features described. In some implementations, such integrated circuits execute instructions that are stored on the circuit itself.

[0067] As used in this specification and any claims of this application, the terms “computer”, “server”, “processor”, and “memory” all refer to electronic or other technological devices. These terms exclude people or groups of people. For the purposes of the specification, the terms display or displaying means displaying on an electronic device. As used in this specification and any claims of this application, the terms “computer readable medium” and “computer readable media” are entirely restricted to tangible, physical objects that store information in a form that is readable by a computer. These terms exclude any wireless signals, wired download signals, and any other ephemeral signals.

[0068] To provide for interaction with a user, implementations of the subject matter described in this specification can be implemented on a specifically configured computer having a display device, e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, for displaying information to the user and a keyboard and a pointing device, e.g., a mouse or a trackball, by which the user can provide input to the computer. Other kinds of specifically configured devices can be used to provide for interaction with a user as well; e.g., feedback provided to the user can be any form of sensory feedback, e.g., visual feedback, auditory feedback, or tactile feedback; and input from the user can be received in any form, including acoustic, speech, or tactile input. In addition, a computer can interact with a user by sending documents to and receiving documents from a device that is used by the user; e.g., by sending web pages to a web browser on a user’s client device in response to requests received from the web browser.

[0069] Implementations of the subject matter described in this specification can be implemented in a specifically configured computing system that includes a back end component, e.g., as a data server, or that includes a middleware component, e.g., an applicationserver, or that includes a front end component, e.g., a client computer having a graphical user interface or a Web browser through which a user can interact with an implementation of the subject matter described in this specification, or any combination of one or more such back end, middleware, or front end components. The components of the system can be interconnected by any form or medium of digital data communication, e.g., a communication network. Examples of communication networks include a local area network (“LAN”) and a wide area network (“WAN”), an inter-network (e.g., the Internet), and peer-to-peer networks (e.g., ad hoc peer-to-peer networks).

[0070] The computing system can include clients and servers. A client and server are generally remote from each other (e.g., physically separated) and may interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other. In some implementations, a server transmits data (e.g., an HTML page) to a client device (e.g., for purposes of displaying data to and receiving user input from a user interacting with the client device). Data generated at the client device (e.g., a result of the user interaction) can be received from the client device at the server.

[0071] Those of skill in the art would appreciate that the various illustrative blocks, modules, elements, components, methods, and algorithms described herein may be implemented as electronic hardware, computer software, or combinations of both. To illustrate this interchangeability of hardware and software, various illustrative blocks, modules, elements, components, methods, and algorithms have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. The described functionality may be implemented in varying ways for each particular application. Various components and blocks may be arranged differently (e.g., arranged in a different order, or partitioned in a different way) all without departing from the scope of the subject technology.

[0072] It is understood that the specific order or hierarchy of steps in the processes disclosed is an illustration of example approaches. Based upon design preferences, it is understood that the specific order or hierarchy of steps in the processes may be rearranged. Some of the steps may be performed simultaneously. The accompanying method claimspresent elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

[0073] Illustration of Subject Technology as Clauses:

[0074] Various examples of aspects of the disclosure are described as numbered clauses (1, 2, 3, etc.) for convenience. These are provided as examples, and do not limit the subject technology. Identifications of the figures and reference numbers are provided below merely as examples and for illustrative purposes, and the clauses are not limited by those identifications.

[0075] Clause 1. A system for improving fluid delivery accuracy of an infusion device, comprises: an infusion pump configured to deliver a fluid through an infusion line loaded into the infusion pump by causing an amount of the fluid to be delivered through an infusion line according to a fluid delivery cycle; and a control unit configured to: receive a command for the infusion pump to initiate a bolus of the fluid; determine, based on receiving the command and before initiating the bolus, a delivery speed and size of the bolus; determine an expected delivery error in an amount of the bolus based on at least one of the determined delivery speed and size of the bolus; identify a predetermined delivery period and a fluid delivery characteristic for completing the bolus according to the fluid delivery cycle; generate an updated fluid delivery characteristic for the identified fluid delivery characteristic based on the identified predetermined delivery period and the identified expected error in the amount of the bolus; and deliver the bolus by causing the fluid to be delivered through the infusion line according to the updated fluid delivery characteristic and an updated fluid delivery cycle.

[0076] Clause 2: The system of Clause 1, wherein the control unit is further configured to determine that at least one of the delivery speed and size of the bolus satisfies a predetermined threshold, wherein the updated fluid delivery characteristic is generated and the bolus is delivered according to the updated fluid delivery characteristic only when the at least one of the delivery speed and size of the bolus satisfies the predetermined threshold.

[0077] Clause 3. The system of Clause 2, wherein determining that at least one of the delivery speed and size of the bolus satisfied a predetermined threshold comprises determining that the delivery speed of the bolus is greater than a predetermined delivery speed and the size of the bolus is less than a predetermined bolus size.

[0078] Clause 4. The system of any one of Clauses 1-3, wherein identifying the expected delivery error comprises: indexing a database based on the delivery speed and the size of the bolus; and obtaining a value of the expected delivery error based on the indexing.

[0079] Clause 5. The system of any one of Clauses 1-4, wherein the predetermined delivery period comprises a predetermined motor duration, and wherein generating the updated fluid delivery characteristic comprises: determining a first motor speed for delivering an amount of the fluid corresponding to the expected delivery error; and adjusting a predetermined motor speed for the bolus by the first motor speed.

[0080] Clause 6. The system of Clause 5, wherein the fluid delivery cycle comprises a predetermined number of motor steps, wherein generating the updated fluid delivery characteristic comprises: estimating a number of motor steps to complete the bolus; reducing the estimated number of motor steps; and wherein delivering the bolus comprises performing the reduced number of motor steps.

[0081] Clause 7. The system of Clause 5, wherein the fluid delivery cycle comprises a complete rotation of a cam responsible for operating a peristaltic pumping mechanism and the predetermined delivery period comprises an amount of cam rotation; and wherein the control unit is further configured to adjust the amount of cam rotation based on at least a portion of the cam rotation associated with the expected delivery error.

[0082] Clause 8. The system of any one of Clauses 1-7, wherein generating the updated fluid delivery characteristic comprises: reducing a predetermined motor speed of the infusion pump during the predetermined delivery period to prevent an over infusion of the fluid to be delivered through an infusion line.

[0083] Clause 9. The system of Clause 8, wherein generating the updated characteristic comprises: reducing the predetermined delivery period by an amount inversely proportional to the determined delivery speed of the bolus such that the predetermined delivery period is reduced more by a first amount when the determined delivery speed is a first flow rate than by a second amount when the determined delivery speed is a second flow rate that is greater than the first flow rate.

[0084] Clause 10. The system of any one of Clauses 1-9, wherein determining the delivery speed and size of the bolus based receiving the command and before initiating thebolus comprises the control unit receiving an input of the delivery speed and size of the bolus with or in connection with the command.

[0085] Clause 11. A method for improving fluid delivery accuracy of an infusion device comprises: operating an infusion pump configured to deliver a fluid through an infusion line loaded into the infusion pump by causing an amount of the fluid to be delivered through an infusion line according to a fluid delivery cycle; receiving a command for the infusion pump to initiate a bolus of the fluid; determining, based on receiving the command and before initiating the bolus, a delivery speed and size of the bolus; determining a magnitude of an expected delivery error in an amount of the bolus based on at least one of the determined delivery speed and size of the bolus; identifying a predetermined delivery period and a fluid delivery characteristic for completing the bolus according to the fluid delivery cycle; generating an updated fluid delivery characteristic for the identified fluid delivery characteristic based on the identified predetermined delivery period and the identified expected error in the amount of the bolus; and configuring the infusion pump to deliver the bolus by causing the fluid to be delivered through the infusion line according to the updated fluid delivery characteristic and an updated fluid delivery cycle.

[0086] Clause 12. The method of Clause 11, further comprising: determining that at least one of the delivery speed and size of the bolus satisfies a predetermined threshold, wherein the updated fluid delivery characteristic is generated and the bolus is delivered according to the updated fluid delivery characteristic only when the at least one of the delivery speed and size of the bolus satisfies the predetermined threshold.

[0087] Clause 13. The method of Clause 12, wherein determining that at least one of the delivery speed and size of the bolus satisfied a predetermined threshold comprises determining that the delivery speed of the bolus is greater than a predetermined delivery speed and the size of the bolus is less than a predetermined bolus size.

[0088] Clause 14. The method of any one of Clauses 11-13, wherein identifying the expected delivery error comprises: indexing a database based on the delivery speed and the size of the bolus; and obtaining a value of the expected delivery error based on the indexing.

[0089] Clause 15. The method of any one of Clauses 11-14, wherein the predetermined delivery period comprises a predetermined motor duration, and wherein generating the updated fluid delivery characteristic comprises: determining a first motor speed for deliveringan amount of the fluid corresponding to the expected delivery error; and adjusting a predetermined speed for the bolus by the first motor speed.

[0090] Clause 16. The method of Clause 15, wherein the fluid delivery cycle comprises a predetermined number of motor steps, wherein generating the updated fluid delivery characteristic comprises: estimating a number of motor steps to complete the bolus; reducing the estimated number of motor steps; and wherein delivering the bolus comprises performing the reduced number of motor steps.

[0091] Clause 17. The method of Clause 15, wherein the fluid delivery cycle comprises a complete rotation of a cam responsible for operating a peristaltic pumping mechanism and the predetermined delivery period comprises an amount of cam rotation; and wherein the method further comprises adjusting the amount of cam rotation based on at least a portion of the cam rotation associated with the expected delivery error.

[0092] Clause 18. The method of any one of Clauses 11-17, wherein generating the updated fluid delivery characteristic comprises: reducing a predetermined motor speed of the infusion pump during the predetermined delivery period to prevent an over infusion of the fluid to be delivered through an infusion line.

[0093] Clause 19. The method of Clause 18, wherein generating the updated characteristic comprises: reducing the predetermined delivery period by an amount inversely proportional to the determined delivery speed of the bolus such that the predetermined delivery period is reduced more by a first amount when the determined delivery speed is a first flow rate than by a second amount when the determined delivery speed is a second flow rate that is greater than the first flow rate.

[0094] Clause 20. A non-transitory computer-readable medium having instructions stored thereon that, when executed by a computing device, cause the computing device to perform a method according to any one of Claims 11 to 19.

[0095] Further Consideration:

[0096] In some embodiments, any of the clauses herein may depend from any one of the independent clauses or any one of the dependent clauses. In one aspect, any of the clauses (e.g., dependent or independent clauses) may be combined with any other one or more clauses(e.g., dependent or independent clauses). In one aspect, a claim may include some or all of the words (e.g., steps, operations, means or components) recited in a clause, a sentence, a phrase or a paragraph. In one aspect, a claim may include some or all of the words recited in one or more clauses, sentences, phrases or paragraphs. In one aspect, some of the words in each of the clauses, sentences, phrases or paragraphs may be removed. In one aspect, additional words or elements may be added to a clause, a sentence, a phrase or a paragraph. In one aspect, the subject technology may be implemented without utilizing some of the components, elements, functions or operations described herein. In one aspect, the subject technology may be implemented utilizing additional components, elements, functions or operations.

[0097] The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. The previous description provides various examples of the subj ect technology, and the subj ect technology is not limited to these examples. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more.” Unless specifically stated otherwise, the term “some” refers to one or more. Pronouns in the masculine (e.g., his) include the feminine and neuter gender (e.g., her and its) and vice versa. Headings and subheadings, if any, are used for convenience only and do not limit the invention described herein.

[0098] The term website, as used herein, may include any aspect of a website, including one or more web pages, one or more servers used to host or store web related content, etc. Accordingly, the term website may be used interchangeably with the terms, web page and server. As used herein a “user interface” (also referred to as an interactive user interface, a graphical user interface or a UI) may refer to a network based interface including data fields and / or other control elements for receiving input signals or providing electronic information and / or for providing information to the user in response to any received input signals. Control elements may include dials, buttons, icons, selectable areas, or other perceivable indicia presented via the UI that, when interacted with (e.g., clicked, touched, selected, etc.), initiates an exchange of data for the device presenting the UI. A UI may be implemented in whole or in part using technologies such as hyper-text mark-up language (HTML), FLASH™, JAVA™,.NET™, web services, or rich site summary (RSS). In some implementations, a UI may be included in a stand-alone client (for example, thick client, fat client) configured to communicate (e.g., send or receive data) in accordance with one or more of the aspects described. The communication may be to or from a medical device, diagnostic device, monitoring device, or server in communication therewith.

[0099] The predicate words “configured to”, “operable to”, and “programmed to” do not imply any particular tangible or intangible modification of a subject, but, rather, are intended to be used interchangeably. For example, a processor configured to monitor and control an operation or a component, may also mean the processor being programmed to monitor and control the operation or the processor being operable to monitor and control the operation. Likewise, a processor configured to execute code can be construed as a processor programmed to execute code or operable to execute code.

[0100] The term automatic, as used herein, may include performance by a computer or machine without user intervention; for example, by instructions responsive to a predicate action by the computer or machine or other initiation mechanism. The word “example” is used herein to mean “serving as an example or illustration.” Any aspect or design described herein as “example” is not necessarily to be construed as preferred or advantageous over other aspects or designs.

[0101] As used herein, the terms “correspond” or “corresponding” encompasses a structural, functional, quantitative and / or qualitative correlation or relationship between two or more objects, data sets, information and / or the like, preferably where the correspondence or relationship may be used to translate one or more of the two or more objects, data sets, information and / or the like so to appear to be the same or equal. Correspondence may be assessed using one or more of a threshold, a value range, fuzzy logic, pattern matching, a machine learning assessment model, or combinations thereof.

[0102] A phrase such as an “aspect” does not imply that such aspect is essential to the subject technology or that such aspect applies to all configurations of the subject technology. A disclosure relating to an aspect may apply to all configurations, or one or more configurations. An aspect may provide one or more examples. A phrase such as an aspect may refer to one or more aspects and vice versa. A phrase such as an “implementation” does not imply that such implementation is essential to the subject technology or that suchimplementation applies to all configurations of the subject technology. A disclosure relating to an implementation may apply to all implementations, or one or more implementations. An implementation may provide one or more examples. A phrase such as an “implementation” may refer to one or more implementations and vice versa. A phrase such as a “configuration” does not imply that such configuration is essential to the subject technology or that such configuration applies to all configurations of the subject technology. A disclosure relating to a configuration may apply to all configurations, or one or more configurations. A configuration may provide one or more examples. A phrase such as a “configuration” may refer to one or more configurations and vice versa.

Claims

WHAT IS CLAIMED IS:

1. A system for improving fluid delivery accuracy of an infusion device, the system comprising: an infusion pump configured to deliver a fluid through an infusion line loaded into the infusion pump by causing an amount of the fluid to be delivered through an infusion line according to a fluid delivery cycle; and a control unit configured to, prior to delivering the fluid: receive a command for the infusion pump to initiate a bolus of the fluid; determine, based on receiving the command and before initiating the bolus, a delivery speed and size of the bolus; determine an expected delivery error in an amount of the bolus based on at least one of the determined delivery speed and size of the bolus; identify a predetermined delivery period and a fluid delivery characteristic for completing the bolus according to the fluid delivery cycle; generate an updated fluid delivery characteristic for the identified fluid delivery characteristic based on the identified predetermined delivery period and the identified expected error in the amount of the bolus; and configure the infusion pump to deliver the bolus by causing the fluid to be delivered through the infusion line according to the updated fluid delivery characteristic and an updated fluid delivery cycle.

2. The system of Claim 1, wherein the control unit is further configured to: determine that at least one of the delivery speed and size of the bolus satisfies a predetermined threshold, wherein the updated fluid delivery characteristic is generated and the bolus is delivered according to the updated fluid delivery characteristic only when the at least one of the delivery speed and size of the bolus satisfies the predetermined threshold.

3. The system of Claim 2, wherein determining that at least one of the delivery speed and size of the bolus satisfied a predetermined threshold comprises determining that the delivery speed of the bolus is greater than a predetermined delivery speed and the size of the bolus is less than a predetermined bolus size.

4. The system of Claim 1, wherein identifying the expected delivery error comprises: indexing a database based on the delivery speed and the size of the bolus; and obtaining a value of the expected delivery error based on the indexing.

5. The system of Claim 1, wherein the predetermined delivery period comprises a predetermined motor duration, and wherein generating the updated fluid delivery characteristic comprises: determining a first motor speed for delivering an amount of the fluid corresponding to the expected delivery error; and adjusting a predetermined motor speed for the bolus by the first motor speed.

6. The system of Claim 5, wherein the fluid delivery cycle comprises a predetermined number of motor steps, wherein generating the updated fluid delivery characteristic comprises: estimating a number of motor steps to complete the bolus; reducing the estimated number of motor steps; and wherein delivering the bolus comprises performing the reduced number of motor steps.

7. The system of Claim 1, wherein the fluid delivery cycle comprises a complete rotation of a cam responsible for operating a peristaltic pumping mechanism and the predetermined delivery period comprises an amount of cam rotation; and wherein the control unit is further configured to adjust the amount of cam rotation based on at least a portion of the cam rotation associated with the expected delivery error.

8. The system of Claim 1, wherein generating the updated fluid delivery characteristic comprises: reducing a predetermined motor speed of the infusion pump during the predetermined delivery period to prevent an over infusion of the fluid to be delivered through an infusion line.

9. The system of Claim 1, wherein generating the updated characteristic comprises: reducing the predetermined delivery period by an amount inversely proportional to the determined delivery speed of the bolus such that the predetermined delivery period is reduced more by a first amount when the determined delivery speed is a first flow rate than by a second amount when the determined delivery speed is a second flow rate that is greater than the first flow rate.

10. The system of Claim 1, wherein determining the delivery speed and size of the bolus based receiving the command and before initiating the bolus comprises the control unit receiving an input of the delivery speed and size of the bolus with or in connection with the command.

11. A method comprising: operating an infusion pump configured to deliver a fluid through an infusion line loaded into the infusion pump by causing an amount of the fluid to be delivered through an infusion line according to a fluid delivery cycle; and prior to delivering the fluid: receiving a command for the infusion pump to initiate a bolus of the fluid; determining, based on receiving the command and before initiating the bolus, a delivery speed and size of the bolus; determining an expected delivery error in an amount of the bolus based on at least one of the determined delivery speed and size of the bolus; identifying a predetermined delivery period and a fluid delivery characteristic for completing the bolus according to the fluid delivery cycle; generating an updated fluid delivery characteristic for the identified fluid delivery characteristic based on the identified predetermined delivery period and the identified expected error in the amount of the bolus; and configuring the infusion pump to deliver the bolus by causing the fluid to be delivered through the infusion line according to the updated fluid delivery characteristic and an updated fluid delivery cycle.

12. The method of Claim 11, further comprising:determining that at least one of the delivery speed and size of the bolus satisfies a predetermined threshold, wherein the updated fluid delivery characteristic is generated and the bolus is delivered according to the updated fluid delivery characteristic only when the at least one of the delivery speed and size of the bolus satisfies the predetermined threshold.

13. The method of Claim 12, wherein determining that at least one of the delivery speed and size of the bolus satisfied a predetermined threshold comprises determining that the delivery speed of the bolus is greater than a predetermined delivery speed and the size of the bolus is less than a predetermined bolus size.

14. The method of Claim 11, wherein identifying the expected delivery error comprises: indexing a database based on the delivery speed and the size of the bolus; and obtaining a value of the expected delivery error based on the indexing.

15. The method of Claim 11, wherein the predetermined delivery period comprises a predetermined motor duration, and wherein generating the updated fluid delivery characteristic comprises: determining a first motor speed for delivering an amount of the fluid corresponding to the expected delivery error; and adjusting a predetermined motor speed for the bolus by the first motor speed.

16. The method of Claim 15, wherein the fluid delivery cycle comprises a predetermined number of motor steps, wherein generating the updated fluid delivery characteristic comprises: estimating a number of motor steps to complete the bolus; reducing the estimated number of motor steps; and wherein delivering the bolus comprises performing the reduced number of motor steps.

17. The method of any one of Claim 11,wherein the fluid delivery cycle comprises a complete rotation of a cam responsible for operating a peristaltic pumping mechanism and the predetermined delivery period comprises an amount of cam rotation; and wherein the method further comprises adjusting the amount of cam rotation based on at least a portion of the cam rotation associated with the expected delivery error.

18. The method of Claim 11, wherein generating the updated fluid delivery characteristic comprises: reducing a predetermined motor speed of the infusion pump during the predetermined delivery period to prevent an over infusion of the fluid to be delivered through an infusion line.

19. The method of Claim 18, wherein generating the updated characteristic comprises: reducing the predetermined delivery period by an amount inversely proportional to the determined delivery speed of the bolus such that the predetermined delivery period is reduced more by a first amount when the determined delivery speed is a first flow rate than by a second amount when the determined delivery speed is a second flow rate that is greater than the first flow rate.

20. A non-transitory computer-readable medium having instructions stored thereon that, when executed by a computing device, cause the computing device to perform a method according to any one of Claims 11 to 19.

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