Ambulatory medical apparatus and method using a telemetry system with predefined reception listening periods

• US 6,585,644 B2
• Filed: 01/22/2001
• Issued: 07/01/2003
• Est. Priority Date: 01/21/2000
• Status: Expired due to Term

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Weiss, Philip T., Starkweather, Timothy J., Shahmirian, Varaz, Villegas, Daniel H., Lebel, Ronald J., Armstrong, John T., Richert, John D., Dennard, Robert C.
• Primary Examiner(s): Nasser, Robert L.
• Assistant Examiner(s): Mallari, Patricia C.
• Application Number:
  US09/768,203
• Publication Number:
  US 20030028184A1
• Time in Patent Office: 890 Days
• Field of Search: 600/300-301, 600/316, 600/347, 600/365, 600/345, 607/32, 607/60, 128/903, 128/904, 340/7.2, 340/7.43, 340/7.51, 340/825, 340/825.36, 370/464, 370/465, 370/470, 370/471, 370/475, 379/93.08, 604/890.1, 604/891.1, 604/27, 604/28, 604/31
• US Class Current: 600/300
• CPC Class Codes: A61B 2560/0209 adapted for power saving
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/6847 mounted on an invasive device
• CPC Class Codes: A61M 2005/14208 with a programmable infusion control system, characterised by the infusion program
• CPC Class Codes: A61M 2205/18 with alarm
• CPC Class Codes: A61M 2205/3507 with implanted devices, e.g. external control
• CPC Class Codes: A61M 2205/3523 using telemetric means
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 2205/581 by audible feedback
• CPC Class Codes: A61M 2205/582 by tactile feedback
• CPC Class Codes: A61M 2205/6018 providing set-up signals for the apparatus configuration
• CPC Class Codes: A61M 2205/8206 battery-operated
• CPC Class Codes: A61M 2207/00 Methods of manufacture, assembly or production
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/14276 specially adapted for implantation
• CPC Class Codes: A61M 5/168 Means for controlling media flow to the body or for metering media to the body, e.g. drip meters, counters ; Monitoring media flow to the body flow control in general G05D7/00
• CPC Class Codes: A61M 5/16831 Monitoring, detecting, signalling or eliminating infusion flow anomalies low-level float-valves causing cut-off A61M5/40; indicating or recording presence, absence or direction of flow in general G01P13/0066
• CPC Class Codes: A61M 5/172 electrical or electronic A61M5/16804, A61M5/16831 take precedence
• CPC Class Codes: A61N 1/37211 Means for communicating with stimulators
• CPC Class Codes: A61N 1/37247 : User interfaces, e.g. input or presentation means
• CPC Class Codes: A61N 1/37254 : Pacemaker or defibrillator security, e.g. to prevent or inhibit programming alterations by hackers or unauthorised individuals
• CPC Class Codes: A61N 1/37258 : Alerting the patient
• CPC Class Codes: A61N 1/37264 : Changing the program; Upgrading firmware
• CPC Class Codes: A61N 1/3727 : characterised by the modulation technique
• CPC Class Codes: A61N 1/37276 : characterised by means for reducing power consumption during telemetry
• CPC Class Codes: A61N 1/37512 : Pacemakers
• CPC Class Codes: G06F 3/0619 : in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/065 : Replication mechanisms
• CPC Class Codes: G06F 3/0673 : Single storage device
• CPC Class Codes: G06F 8/60 : Software deployment
• CPC Class Codes: G06F 8/65 : Updates security arrangements therefor G06F21/57
• CPC Class Codes: G16H 20/17 : delivered via infusion or injection
• CPC Class Codes: G16H 40/40 : for the management of medical equipment or devices, e.g. scheduling maintenance or upgrades
• CPC Class Codes: Y02D 10/00 : Energy efficient computing, e.g. low power processors, power management or thermal management
• CPC Class Codes: Y10S 128/13 : Infusion monitoring
• CPC Class Codes: Y10S 128/903 : Radio telemetry
• CPC Class Codes: Y10T 29/49117 : Conductor or circuit manufacturing
• CPC Class Codes: Y10T 29/49826 : Assembling or joining

Abstract

An implanted medical device (e.g. infusion pump) and an external device communicate with one another via telemetry messages that are receivable only during windows or listening periods. Each listening period is open for a prescribed period of time and is spaced from successive listening periods by an interval. The prescribed period of time is typically kept small to minimize power consumption. To increase likelihood of successful communication, the window may be forced to an open state, by use of an attention signal, in anticipation of an incoming message. To further minimize power consumption, it is desirable to minimize use of extended attention signals, which is accomplished by the transmitter maintaining an estimate of listening period start times and attempting to send messages only during listening periods. In the communication device, the estimate is updated as a result of information obtained with the reception of each message from the medical device.

Claims

1. A medical system, comprising:

a) an ambulatory medical device (MD) comprising MD electronic control circuitry that further comprises at least one MD telemetry system and at least one MD processor that controls, at least in part, operation of the MD telemetry system and operation of the medical device, wherein the medical device is configured to provide a treatment to a body of a patient or to monitor a selected state of the body; and

b) a communication device (CD) comprising CD electronic control circuitry that further comprises at least one CD telemetry system and at least one CD processor that controls, at least in part, operation of the CD telemetry system and operation of the communication device, wherein the CD telemetry system sends messages to or receives messages from the MD telemetry system,

wherein at least one of the communication device or the medical device sets a preamble length, for at least some messages, as a function of at least the difference between a present time and a time of a previous communication.

2. The system of claim 1 wherein a first portion of the MD telemetry system is incorporated into the MD processor and a second portion of the MD telemetry system is external to the MD processor, or wherein a first portion of the CD telemetry system is incorporated into the CD processor and a second portion of the CD telemetry system is external to the CD processor.

3. The system of claim 2 wherein (1) the MD electronic control circuitry comprises at least one external MD functional module, other than the second portion of the MD telemetry system, that is external to the MD processor, (2) the CD electronic control circuitry comprises at least one external CD functional module, other than the second portion of the CD telemetry system, that is external to the CD processor, (3) the MD processor comprises an internal MD CPU and at least one other internal MD functional module, or (4) the CD processor comprises an internal CD CPU and at least one other internal CD functional module.

4. The system of claim 1 wherein the medical device comprises at least one of (1) an implantable infusion pump for selectively dispensing a selected drug, (2) an implantable infusion pump for selectively dispensing insulin, (3) an implantable sensor for sensing a selected state of the body, (4) an implantable sensor for sensing glucose level, or (5) an implantable electrode for selectively stimulating a portion of the body of the patient.

5. The medical system, of claim 1,

wherein the medical device sends outbound messages to the communication device and the communication device receives outbound messages from the medical device,

wherein the medical device receives inbound messages from the communication device and the communication device sends inbound messages to the medical device,

wherein the medical device listens for inbound messages beginning at an inbound listening start time and continuing for an inbound listening period,

wherein the communication device listens for outbound messages beginning at an outbound listening start time and continuing for an outbound listening period,

wherein the medical device transmits outbound messages beginning at an outbound transmission start time and continues transmission of a selected portion of the outbound messages for an outbound transmission period,

wherein the communication device transmits inbound messages beginning at an inbound transmission start time and continues transmission of a selected portion of the inbound messages for an inbound transmission period,

wherein an interval exists between successive inbound listening periods,

wherein an interval exists between successive outbound listening periods,

wherein at least a selected one of (1) or (2) occurs:

(1) at least one of the inbound transmission period or the outbound transmission period is extended after a failure to communicate occurs;

or

(2) at least one of the inbound transmission start times or outbound transmission start times undergoes a shift relative to an anticipated inbound listening start time or an anticipated outbound listening start time, respectively; and

wherein after one or more extensions and/or one or more shifts, all portions of the interval between successive inbound or outbound listening periods would be broadcast to during inbound transmission periods or outbound transmission periods, respectively.

6. The system of claim 5 wherein a first portion of the MD telemetry system is incorporated into the MD processor and a second portion of the MD telemetry system is external to the MD processor, or wherein a first portion of the CD telemetry system is incorporated into the CD processor and a second portion of the CD telemetry system is external to the CD processor.

7. The system of claim 6 wherein (1) the MD electronic control circuitry comprises at least one external MD functional module, other than the second portion of the MD telemetry system, that is external to the MD processor, (2) the CD electronic control circuitry comprises at least one external CD functional module, other than the second portion of the CD telemetry system, that is external to the CD processor, (3) the MD processor comprises an internal MD CPU and at least one other internal MD functional module, or (4) the CD processor comprises an internal CD CPU and at least one other internal CD functional module.

8. The system of claim 5 wherein (1) the MD electronic control circuitry comprises at least one external MD functional module, other than the second portion of the MD telemetry system, that is external to the MD processor, (2) the CD electronic control circuitry comprises at least one external CD functional module, other than the second portion of the CD telemetry system, that is external to the CD processor, (3) the MD processor comprises an internal MD CPU and at least one other internal MD functional module, or (4) the CD processor comprises an internal CD CPU and at least one other internal CD functional module.

9. The system of claim 5 wherein the medical device comprises at least one of (1) an implantable infusion pump for selectively dispensing a selected drug, (2) an implantable infusion pump for selectively dispensing insulin, (3) an implantable sensor for sensing a selected state of the body, (4) an implantable sensor for sensing glucose level, or (5) an implantable electrode for selectively stimulating a portion of the body of the patient.

10. The system of claim 1, wherein the preamble length is extended, based on the difference between a present time and a time of a previous communication.

11. The system of claim 1, wherein a preamble for at least some messages comprises a repeating pattern of bits.

12. The system of claim 1, wherein a preamble for at least some messages comprises an alternating pattern of ones and zeros.

13. The system of claim 1, wherein a preamble for messages being sent from the CD telemetry system to the MD telemetry system have a different length than a preamble for messages being received by the DC telemetry system from the MD telemetry system.

14. The system of claim 1, wherein said messages comprises a preamble and data.

15. The system of claim 14, wherein a preamble for at least some messages comprises an attention preamble pattern of bits and wherein a receiver of at least one of the CD telemetry system and the MD telemetry system operates to continue to track received bits of a message, in response to receiving the attention preamble pattern of bits for the message.

16. The system of claim 1, wherein a preamble for at least some messages comprises an attention preamble pattern of bits and wherein a receiver of at least one of the CD telemetry system and the MD telemetry system operates to continue to track received bits of a message, in response to receiving the attention preamble pattern of bits for the message.