Delivery of aerosol medication for inspiration

• US 5,813,397 A
• Filed: 04/25/1997
• Issued: 09/29/1998
• Est. Priority Date: 03/05/1991
• Status: Expired due to Fees

• Current Assignee: Aradigm Corporation
• Original Assignee: Aradigm Corporation
• Inventors: Rubsamen, Reid M., Goodman, David E.
• Primary Examiner(s): Lewis, Aaron J.
• Application Number:
  US08/845,802
• Time in Patent Office: 522 Days
• Field of Search: 128/200.14, 128/200.23, 128/204.23
• US Class Current: 128/200.14
• CPC Class Codes: A61J 7/0418 with electronic history memory
• CPC Class Codes: A61M 11/002 by flow deviation causing inertial separation of transported particles
• CPC Class Codes: A61M 15/00 Inhalators drug delivery in endotracheal tubes A61M16/04
• CPC Class Codes: A61M 15/0021 Mouthpieces therefor
• CPC Class Codes: A61M 15/0066 with means for varying the dose size
• CPC Class Codes: A61M 15/008 Electronic counters
• CPC Class Codes: A61M 15/009 using medicine packages with incorporated spraying means, e.g. aerosol cans pocket atomiser of the injector type A61M11/08
• CPC Class Codes: A61M 15/0091 mechanically breath-triggered
• CPC Class Codes: A61M 16/0858 Pressure sampling ports
• CPC Class Codes: A61M 16/202 electrically actuated
• CPC Class Codes: A61M 2016/0021 with a proportional output signal, e.g. from a thermistor
• CPC Class Codes: A61M 2016/0036 in the breathing tube and used in both inspiratory and expiratory phase
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 2205/60 with identification means
• CPC Class Codes: A61M 2205/6018 providing set-up signals for the apparatus configuration
• CPC Class Codes: A61M 2205/6027 Electric-conductive bridges closing detection circuits, with or without identifying elements, e.g. resistances, zener-diodes
• CPC Class Codes: A61M 2205/6036 characterised by physical shape, e.g. array of activating switches
• CPC Class Codes: A61M 2205/6045 having complementary physical shapes for indexing or registration purposes
• CPC Class Codes: A61M 2205/8206 battery-operated
• CPC Class Codes: A61M 2205/8212 : with means or measures taken for minimising energy consumption
• CPC Class Codes: B01F 23/2132 : using nozzles
• CPC Class Codes: B01F 35/711 : for feeding a mixture of components, i.e. solids in liquid, solids in a gas stream
• CPC Class Codes: B01F 35/7179 : using sprayers, nozzles or jets
• CPC Class Codes: F16H 35/00 : Gearings or mechanisms with other special functional features
• CPC Class Codes: G01F 1/363 : with electrical or electro-mechanical indication G01F1/37 and G01F1/38 take precedence
• CPC Class Codes: G01F 1/40 : Details of construction of the flow constriction devices
• CPC Class Codes: G01F 1/44 : Venturi tubes
• CPC Class Codes: G01F 1/50 : Correcting or compensating means
• CPC Class Codes: G01F 13/006 : measuring volume in function of time
• CPC Class Codes: G01F 15/002 : for gases
• CPC Class Codes: G01F 25/10 : of flowmeters
• CPC Class Codes: G01F 7/005 : by measuring pressure or differential pressure, created by the use of flow constriction

Abstract

Apparatus and methods for delivering an amount of aerosolized medicine for inspiration by a patient in response to the occurrence of appropriate delivery point or points in the patient'"'"'s detected breath flow. The aerosol medication may be administered as one or more pulses having a pulse width, shape, and frequency that will maximize the respirable fraction of the aerosolized compound being administered. The delivery point or points may be predetermined or determined from a prior inspiratory flow for depositing the selected medication at one or more desired locations in the patient'"'"'s airway. Determined delivery points are recursively lowered for each inspiratory flow that does not satisfy one of the predetermined and previously lowered threshold. Changes in the patient'"'"'s breath flow patterns during the course of an aerosolized medication inspiration therapy program may be detected and used to adjust the controlled amount of medication to be delivered in a given administration and/or to inform the patient of the patient'"'"'s condition or change in condition. The device also may contain a library of administration protocols or operating parameters for different medications and a means for identifying from the canister the medicinal contents of the canister for customizing operation of the apparatus.

Claims

1. A method for delivering an aerosol of insulin to a subject for inspiration, said method characterized by:

monitoring inspiratory flow;

calculating a firing threshold parameter based on the monitored inspiratory flow;

determining whether each detected inspiratory flow is one of a first flow detected following a reset flow event or a subsequent flow detected following a detected flow that is not followed by a reset flow event, the reset flow event being any of a release of an amount of insulin and initialization of operation of the apparatus;

selecting a delivery threshold corresponding to a point in the detected inspiratory flow at which an amount of an aerosol of insulin is to be released characterized by selecting a preselected delivery threshold in response to the detected inspiratory flow being a determined first flow and selecting a calculated delivery threshold that is calculated based on a sensed flow parameter of the preceding detected inspiratory flow in response to the detected inspiratory flow being a determined subsequent flow; and

determining whether or not the detected inspiratory flow satisfies the selected delivery threshold, and

(i) in response to the detected inspiratory flow satisfying the selected delivery threshold, releasing an amount of the narcotic to generate an aerosol of insulin; and

(ii) in response to determining that the detected inspiratory flow did not satisfy the selected delivery threshold, calculating a new delivery threshold based on the detected inspiratory flow so that the selected delivery threshold for the next detected inspiratory flow determined to be a subsequent flow is the last calculated delivery threshold.

2. A method for administering an aerosol of insulin, said method characterized by:

(a) monitoring inspiratory flow of a subject through an inspiratory flow path;

(b) automatically determining, based on a selected flow or volume parameter of a first monitored inspiratory flow, a delivery threshold for the release of an amount of an aerosol of insulin; and

(c) delivering in response to a second monitored inspiratory flow satisfying the determined delivery threshold an amount of aerosol of insulin for inspiration during the second monitored inspiratory flow, the second monitored inspiratory flow following the first monitored inspiratory flow.

3. A method for controlling inhalation therapy using an inhaler device for releasing an amount of an aerosol of insulin for inspiration by a patient in response to a sufficient inspiratory flow characterized by:

monitoring a patient'"'"'s breath flow including the inspiratory flow;

determining a pulmonary function based on a detected breath flow, the determined pulmonary function being selected from among the group consisting of forced expiratory volume, forced vital capacity, and peak expiratory flow rate;

comparing a first determined pulmonary function based on a first detected breath flow and a second determined pulmonary function based on a second detected breath flow;

determining relative changes in the determined pulmonary function; and

displaying a parameter corresponding to the determined relative changes in the first and second determined pulmonary functions.