Infusion Pump Device and Method for Improved Dosing

• US 20140046288A1
• Filed: 10/09/2013
• Published: 02/13/2014
• Est. Priority Date: 04/12/2011
• Status: Active Grant

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diagnostics International AG (Roche Holding AG)
• Inventors: Geipel, Andreas, Dogwiler, Joerg, Haueter, Ulrich, Scheurer, Simon, Zihlmann, Rudolf, Teutsch, David, Kuehni, Florian, Schaltegger, Reto
• Granted Patent: US 9,402,951 B2
• Time in Patent Office: Days
• US Class Current: 604/500
• CPC Class Codes: A61M 2005/1402 Priming
• CPC Class Codes: A61M 2005/14208 with a programmable infusion control system, characterised by the infusion program
• CPC Class Codes: A61M 2005/14264 with means for compensating influence from the environment
• CPC Class Codes: A61M 2005/16868 Downstream occlusion sensors
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: A61M 2205/3355 Controlling downstream pump pressure
• CPC Class Codes: A61M 2205/3365 Rotational speed
• CPC Class Codes: A61M 2205/3396 Reservoirs being alternately filled and emptied for measuring flow rate or delivered volume
• CPC Class Codes: A61M 5/142 Pressure infusion, e.g. using pumps
• CPC Class Codes: A61M 5/14216 Reciprocating piston type
• CPC Class Codes: A61M 5/16809 by repeated filling and emptying of an intermediate volume pressure infusion using positive displacement pumps A61M5/142
• CPC Class Codes: A61M 5/31511 Piston or piston-rod constructions, e.g. connection of piston with piston-rod A61M5/5066 takes precedence
• CPC Class Codes: A61M 5/365 Air detectors A61M5/1684 takes precedence; in extracorporeal blood circuits A61M1/3626

Abstract

An infusion pump device comprising a primary liquid medicament reservoir, a pump with a secondary reservoir to retrieve medicament from the primary reservoir and to subsequently dose the medicament from the secondary reservoir in adjustable volumes (V_dose,i) to a downstream conduit and a control unit to control the operation of the infusion pump device is presented. For metering the volumes (V_dose,i), the control unit causes the infusion pump device to: (a) determine a maximum refill level (V_C,max) for the secondary reservoir, based on external parameters, wherein the maximum refill level does not exceed the maximum capacity of the secondary reservoir; (b) fill the secondary reservoir with medicament from the primary reservoir to the maximum refill level (V_C,max); (c) meter and convey the medicament volumes to the downstream conduit; (d) if the secondary reservoir becomes empty, refill the secondary reservoir as in step (b) and continue with step (c).

Claims

1. An infusion pump device comprising a primary reservoir for liquid medicament, a pump with a secondary reservoir to retrieve liquid medicament from the primary reservoir and to subsequently dose the liquid medicament from the secondary reservoir in one or more portions of adjustable volume (V_dose,i) to a downstream conduit, and a control unit to control the operation of the infusion pump device, wherein for metering the multitude of portions (V_dose,i) the control unit causes the infusion pump device to carry out the following steps:

filling the secondary reservoir with liquid medicament from the primary reservoir to a certain adjustable refill level (V_refill);

metering and conveying at certain points in time (t_i) the different portions (V_dose,i) of liquid medicament to the downstream conduit; and

if the secondary reservoir becomes empty, refilling the secondary reservoir and continuing with metering and conveying;

wherein the control unit on a regular basis determines a maximum refill level (V_C,max) for the secondary reservoir or retrieves such a maximum refill level (V_C,max) from another source, wherein the volumes (V_dose,i) of the one more portions of liquid medicament to be metered and the points in time (t_i) at which they are metered and conveyed are independent from the maximum refill level (V_C,max), and wherein during the metering of the multitude of portions (V_dose,i), the control unit restricts the filling of the secondary reservoir to a refill level (V_refill) that is smaller or equal the maximum refill level (V_C,max).

2. The infusion pump device according to claim 1, wherein if the secondary reservoir becomes empty during the metering of a single portion of liquid medicament and has to be refilled, the maximum refill level for that particular refilling step is increased to an increased maximum refill level V_C,max′

=V_C,max+V_dose,rem, with V_dose,rem being the remaining volume of the single portion that has not yet been completely metered.

3. The infusion pump device according to claim 1, wherein if the next single portion (V_dose,i) of liquid medicament to metered is above a certain threshold, the secondary reservoir is refilled to the maximum refill level (V_C,max) prior or after administration of the single portion.

4. The infusion pump device according to claim 1, wherein if the secondary reservoir becomes empty during the metering of the next single portion (V_dose,i,next) of liquid medicament, prior to metering the next portion the secondary reservoir is refilled with liquid medicament from the primary reservoir, to an increased maximum refill level V_C,max′

=V_C,max+V_dose,i,next, with V_dose,i,next being the volume of the single portion that is to be metered next.

5. The infusion pump device according to claim 1, wherein if the secondary reservoir becomes empty during the metering of a single portion of liquid medicament and has to be refilled, the refilling of the secondary reservoir is divided in two steps;

wherein in a first step the secondary reservoir is filled with liquid medicament from the primary reservoir to a volume level V_dose,rem, with V_dose,rem being the remaining volume of the single portion that has not yet been completely metered, and the remaining volume is metered and conveyed, and in a second step the secondary reservoir is filled to the maximum refill level (V_C,max).

6. The infusion pump device according to claim 1, wherein the control unit or a separate system on a regular basis recalculates the maximum refill level (V_C,max) as a function of the average volume of liquid that has been metered within a certain time period in the past, and if the recalculation has been carried out by a separate system subsequently provides the recalculated maximum refill level (V_C,max) to the control unit, e.g by storing it in a memory unit.

7. The infusion pump device according to claim 6, wherein the maximum refill level (V_C,max) is recalculated based on the average volume of liquid that has been metered within a period that includes at least the last 24 hours.

8. The infusion pump device according to claim 1, further comprising,

one or more sensor units to detect changes in environmental temperature and/or environmental pressure.

9. The infusion pump device according to claim 1, wherein the control unit, or a separate system, on a regular basis recalculates the maximum refill level (V_C,max) as a function of the changes in environmental temperature and/or environmental pressure within a certain time period in the past, and if the recalculation has been carried out by a separate system subsequently provides the recalculated maximum refill level (V_C,max) to the control unit by storing it in a memory unit.

19. The method according to claim 10, wherein the method is carried out with an infusion pump device according claim 1.

10. A method for operating an infusion pump device comprising a primary reservoir for the liquid medicament, and a pump with a secondary reservoir retrieves liquid medicament from the primary reservoir and subsequently conveys the liquid medicament from the secondary reservoir in one or more portions of adjustable volume (V_dose,i) to a downstream conduit, wherein for metering the multitude of portions (V_dose,i), the method comprises:

filling the secondary reservoir with liquid medicament from the primary reservoir to a certain adjustable refill level (V_refill);

metering and conveying at certain points in time (t_i) the different portions (V_dose,i) of liquid medicament to the downstream conduit; and

if the secondary reservoir becomes empty, refilling the secondary reservoir and continuing with metering and conveying, wherein on a regular basis a maximum refill level (V_C,max) for the secondary reservoir (14) is determined, or is retrieved from another source, wherein the volumes (V_dose,i) of the one more portions of liquid medicament to be metered and the points in time (t_i) at which they are metered and conveyed are independent from the maximum refill level (V_C,max), and wherein during the metering of the multitude of portions (V_dose,i) the filling of the secondary reservoir is restricted to a refill level (V_refill) that is smaller or equal the maximum refill level (V_C,max).

11. The method according to claim 10, wherein if the secondary reservoir becomes empty during the metering of a single portion of liquid medicament and has to be refilled, the maximum refill level for that particular refilling step is increased to an increased maximum refill level V_C,max′

=V_C,max+V_dose,rem, with V_dose,rem being the remaining volume of the single portion that has not yet been completely metered.

12. The method according to claim 10, wherein if the next single portion (V_dose,i) of liquid medicament to metered is above a certain threshold, the secondary reservoir is refilled to the maximum refill level prior or after administration of the single portion.

13. The method according to claim 10, wherein if the secondary reservoir becomes empty during the metering of the next single portion (V_dose,i,next) of liquid medicament, prior to metering the next portion the secondary reservoir is refilled with liquid medicament from the primary reservoir, to an increased maximum refill level V_C,max′

=V_C,max+V_dose,i,next, with V_dose,i,next being the volume of the single portion that is to be metered next.

14. The method according to claim 10, wherein if the secondary reservoir becomes empty during the metering of a single portion of liquid medicament and has to be refilled, the refilling of the secondary reservoir is divided in two steps;

wherein in a first step the secondary reservoir is filled with liquid medicament from the primary reservoir to a volume level V_dose,rem, with V_dose,rem being the remaining volume of the single portion that has not yet been completely metered, and the remaining volume is metered and conveyed, and in a second step the secondary reservoir is filled to the maximum refill level (V_C,max).

15. The method according to claim 10, wherein on a regular basis the maximum refill level (V_C,max) is recalculated as a function of the average volume of liquid that has been metered within a certain time period in the past.

16. The method according to claim 15, wherein the maximum refill level (V_C,max) is recalculated based on the average volume of liquid that has been metered within a period that includes at least the last 24 hours.

17. The method according to claim 10, further comprising,

one or more sensor units that are able to detect changes in environmental temperature and/or environmental pressure.

18. The method according to claim 10, wherein that on a regular basis the maximum refill level (V_C,max) is recalculated as a function of the changes in environmental temperature and/or environmental pressure within a certain time period in the past.