Inhalers or puffers may be used for delivering medication into the body via the lungs. They can be used, for example, in the treatment of asthma and chronic obstructive pulmonary disease (COPD). Types of inhalers may include metered dose inhalers (MDIs), dry powder inhalers (DPIs) and nebulizers.
A common problem faced in respiratory drug delivery is how to monitor patient adherence and compliance. Adherence deals with the patient following the prescription label, for example taking the prescribed number of doses per day. For example, if the prescription calls for two doses each day, and the patient is taking two doses a day, they are considered 100% adherent. If the patient is only taking one dose a day, they are only 50% adherent. In the latter case, the patient is not getting the treatment prescribed by their doctor.
Compliance, on the other hand, relates to how the patient uses their drug delivery device. If used in the manner recommended for effective treatment, they are 100% compliant. If not used properly however, they are less than 100% compliant. Use of a breath-actuated inhaler (e.g., a dry powder inhaler (DPI)) involves inhaling in a particular way; for example the inhalation may need to be long enough and hard enough to entrain a full dose of medicament. For some patients, for example children and the elderly, meeting the requirements for full compliance may be difficult. Failing to achieve 100% compliance can reduce the effectiveness of the prescribed medicament.
It is difficult for a patient to determine whether he or she inhaled the prescribed dose of medication and thus to verify compliance with the prescription. Especially for DPIs, a patient may not immediately notice that medication is being inhaled (e.g., because the particles are so small they may not be fell or tasted). A patient may learn of inhalation after seeing the medical effects and still may not know whether the amount of inhaled medication complies with the prescript ion.
The present disclosure generally relates to assisting patient compliance with medicament administration via an inhaler. For example, the disclosure may relate to the use of indicators to indicate when the inhaler is ready for releasing a dose and when the patient has inhaled sufficient to receive the recommended dose.
An inhaler may include a mouthpiece cover, a pressure sensor, a first indicator, and a second indicator. The first indicator may be a first light and the second indicator may be a second light. The first indicator may be a first state of a light and the second indicator may be a second state of the light. The first indicator may be configured to indicate based on a state of the mouthpiece cover. For example, the first indicator may be configured to illuminate based on an open state of the mouthpiece cover, where for example, medication may be ready for inhalation based on the open state of the mouthpiece cover. For example, medication may be transferred from a reservoir to a dosing cup based on the open state of the mouthpiece cover. The second indicator may be configured to indicate based on an output of the pressure sensor. For example, the second indicator may be configured to illuminate based on a pressure measurement in the mouthpiece or elsewhere in the inhaler exceeding a predetermined threshold. The predetermined threshold may be associated with administration of medication.
An inhaler may include a mouthpiece cover, a pressure sensor, and/or a light. The light may be configured to provide a first indication based on a state of the mouthpiece cover and a second indication based on an output of the pressure sensor. The first indication and the second indication may be different colors of the light. At least one of the first indication and the second indication may be a provided by flashing the light. The inhaler may include a dosing cup. A dose of medication may be released to the dosing cup based on a movement of the mouthpiece cover.
An inhaler may include a mouthpiece cover, a first light, and a second light. The first and second lights may be configured to indicate that the inhaler is ready for inhalation based on a state of the mouthpiece cover and to indicate inhalation. The first light may be configured to indicate that the inhaler is ready for inhalation based on the mouthpiece cover reaching an open state. The inhaler may include a dosing cup. A dose of medication may be released to the dosing cup based on a movement of the mouthpiece cover. The first light may indicate that the inhaler is ready for inhalation based on the inhaler being in an upright orientation.
The inhaler may include a sensor configured to provide an output based on air flow through a mouthpiece of the inhaler, which for example may be indicative of user inhalation. For example, the second light may be configured to indicate inhalation based on the sensor output. The second light may be configured to indicate inhalation based on a determination that an amount of inhaled medication has (e.g., and/or has not) reached a predetermined threshold (e.g., using the sensor). For example, the second light may be configured to flash to indicate that a sensor measurement has reached a first threshold (e.g., indicative of user inhalation) and to turn on based on a determination that a sensor measurement has reached a second predetermined threshold (e.g., indicative that an amount of inhaled medication has be delivered to the user).
The PCB 150, which may carry a processor and transmitter, may be incorporated into the top of the inhaler 100 body. A collar 197 around the PCB 150 may be clipped onto the top of the yoke (not shown) towards the end of manufacture of the inhaler 100. This may be done following sterilization of parts of the inhaler body. This may be advantageous since the sterilization process may damage the sensitive electronics on the PCB 150.
The yoke 190 may be configured to rise when the mouthpiece cover 180 is opened. This may push the horizontal top part of the yoke 190 up to close the tactile switch 195. When the switch 195 is closed, an electrical connect ion may be formed between the PCB 150 and a battery 155, such as a coin cell, so that the PCB 150 may be powered up when the mouthpiece cover 180 is open. In an example, the PCB 150 may always be connected to the battery 155, but closing of the switch 195 (e.g., or activation of some other switching means, e.g. an optical sensor, an accelerometer or a Hall effect sensor) may wake the PCB 150 from a power-conserving sleep node. For example, the PCB 150 may always be powered on and the circuit of the electronics module may be in standby, and opening of the mouthpiece cover 180 may wake up the circuitry of the electronics module (e.g., bring the electronics module out of sleep mode and into a full powered on state). Indicator light emitting diodes (LEDs) visible through (e.g., optionally colored) windows or light pipes shown on the exterior of the inhaler 100, for example, in a position visible to a user during dosing, may also be powered by battery 155 and may be controlled by a processor on the PCB. The indicator 152 may be used to provide information to a user and/or caregiver by indicating, for example with different color and flash combinations, that e.g. the mouthpiece cover is open (e.g., and therefore the inhaler is primed for dosing) and/or it is time to refill a prescription and/or that (e.g., according to processing of the pressure sensor readings) dosing is complete/has not been fully completed.
Based on the information received from the switch 495 and/or the sensor 410, the processor 457 may determine that the pressure reading (e.g., which may be indicative of medication inhaled by a user) reached a predetermined level. There may be a lookup table for the predetermined level with which the processor compares the pressure reading. When the predetermined level is reached, the processor 457 may send a signal to one or more indicator(s) 452 to indicate the state of the inhaler. The processor 457 may store in memory the pressure reading, a time stamp for the pressure reading, and/or information derived based on the pressure reading (e.g., medication dosed, medication administered to the user, medication administered in full to the user, air flow through the mouthpiece, etc.). For example, the processor 457 may access information (e.g., a lookup table for the predetermined level of medication) from, and store data in, any type of suitable memory, such as non-removable memory and/or removable memory. The non-removable memory may include random-access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. The processor may access information from, and store data in, memory that is not physically located within the inhaler, such as on a server.
The processor 457 may comprise a microcontroller, a programmable logic device (PLD), a microprocessor, an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or any suitable processing device, controller, or control circuit. The processor 457 may comprise an internal memory. The processor 457 may receive power from the power source 455, and may be configured to distribute and/or control the power to the other components in the inhaler 400. The power supply may be any suitable device for powering the inhaler. The switch 495 may not be connected to the processor 457, but the power source 455. The power source may be directly connected to one or more of the sensor 410, memory 445, the indicator(s) 452, and transceiver 460.
Indicators and an electronics module may be permanently attached to an inhaler. As shown in
Figure S illustrates how an electronics module 550 (e.g., compliance module) may be incorporated into the top of an inhaler (e.g., the inhaler 100) whether the indicators and electronics module are permanent or removable. The electronics module 550 may be an example of the electronics module 400 of
Example methods of using a sensor to detect inhalation are provided below. Although the examples below use a pressure sensor, specifically a barometric pressure sensor, an inhaler (e.g., the inhaler 100) may use other types of sensors to measure the inhalation.
A spirometer is an apparatus for measuring the volume of air inspired and expired by a patient's lungs. Spirometers measure ventilation, the movement of air into and out of the lungs. From the traces, known as spirograms, output by spirometers, it is possible to identify abnormal (e.g., obstructive or restrictive) ventilation patterns. Spirometers may use a variety of different measurement methods including pressure transducers, ultrasonic and water gauge.
In order to monitor the flows associated with breathing, a pressure sensor may be convenient because pressure information can be used to determine flow, which can then be used to determine volume.
Pressure sensors used for breath detection may measure the pressure difference across a section of the patient airway. This may be done using two connections, by tubing or other suitable conduit, to connect the sensor to the airway. It may also be possible to use a single connection to the airway, with the other port open to the atmosphere. A single port gauge type sensor can also be used if the pressure within the airway is measured both before and after flow is applied, the difference in readings representing the desired pressure drops across the air path resistance.
In addition to the differential (two port) type pressure sensors and the single port-gauge type sensors, with separate measurements made before and after use, absolute or barometric pressure sensors may be available. Barometric pressure sensors are referenced to vacuum. They are sometimes referred to as altimeters since altitude can be deduced from barometric pressure readings.
However, with miniaturization, including the introduction of MEMS and NEMS technologies, much improved sensors are now available. A MEMS barometric sensor may be capable of operation from 20 kPa to 110 kPa and can detect flow rates of less than 30 lpm (litres per minute) when pneumatically coupled to a flow path having a known flow resistance.
Using a barometric sensor may enable use of the barometric pressure as a baseline throughout the measurement cycle, and thus it may address the uncertainty of other single port approaches.
Also, having knowledge of the local barometric pressure may provide some insight into patient lung function. It is suspected that changes in atmospheric pressure, such as those associated with approaching storm fronts, may have an effect on patient breathing, possibly even related to asthma and COPD events.
Barometric pressure sensors may already be in stressed condition, having an integral reference port sealed within the device under vacuum. This means that they have low hysteresis in the region of interest.
Due to the extremely small size and mass of their sensing elements, MEMS sensors may be capable of reacting to extremely small pressure changes. Some are capable of resolving pressure changes as low as 1 Pa.
For example, the Freescale MPL3115A2 MEMS barometer/altimeter chip (pressure 20 sensor) is digital, using an I2C interface to communicate pressure information to a host micro-computer.
MEMS pressure sensors can be packaged in metal. This may provide RF shielding and good thermal conductivity for temperature compensation.
MEMS pressure sensors are also low cost, exhibit low power consumption and are very small. This makes them especially suitable for use in portable and/or disposable devices which may, for example, be powered by batteries such as coin cells.
The small size of MEMS pressure sensors may make it easy to incorporate them into existing designs of inhalers. It may be easier to incorporate them in or close to a mouthpiece to more accurately measure the pressure change caused by a patient's inhalation or exhalation.
A miniature barometric pressure sensor can be connected directly to the patient airway using only a small hole to the air path which does not require tubing of any kind. This may reduce the possibility of moisture condensation and potential bacterial growth associated with elastomeric tubing. An internal seal, for example a gel seal, can be included to protect the sensor element from contamination.
The miniature pressure sensor (e.g., the entire miniature pressure sensor) may be encapsulated within a chamber adjacent to the flow channel, for example, instead of positioning the seal 640 around the channel between opening 621 and sensor port 611. Pneumatic seal may be located outside of the sensor footprint and may extend all the way from the exterior of flow channel wall to the surface on which the sensor may be mounted (for example the component surface of a PCB).
MEMS sensors may be available with built-in temperature compensation. In an example, external thermal sensors may be used. In an example, external thermal sensors may not be used. Compensation may be provided right at the measurement site, increasing the accuracy of the compensation. A MEMS sensor with built-in temperature compensation may also act as a compact breath thermometer, providing further information to the patient and/or their caregiver. If the housing of the sensor is metal, then not only may the sensitive internal circuitry be isolated from RF fields, such as those associated with mobile phones or nearby disturbances, but the sensor may also rapidly equilibrate to the local temperature in order to provide optimum temperature compensation.
The addition of a miniature barometric pressure sensor anywhere in the airflow path through the inhaler or anywhere in fluid communication with the airflow path may enable compliance monitoring since such a miniature sensor may collect sufficient data to indicate whether or not the patient inhaled in an appropriate manner (e.g. hard enough and for long enough) to entrain a full dose of medicament. This information, combined with a signal originating from the dose metering system indicating that a bolus of medicament was made available to the flow channel through which the patient inhales prior to the inhalation, may be sufficient to confirm that a dose has been successfully administered.
It should be noted that due to their small size, MEMS pressure sensors can be used to monitor patient flow through, for example, nebulisers, DPIs or pMDIs, thus facilitating low cost compliance monitoring, in addition to/in place of adherence monitoring, which confirms device actuation. Said compliance monitoring could be implemented using an accessory device that couples to the dosing device through a small hole to the airway to be monitored, or in the dosing device itself. The small size, high performance and low cost of MEMS sensors may make them ideally suited to such applications where size and weight are major considerations for users who may have to carry their inhaler with them at all times.
If output from the miniature pressure sensor is digital, all low level signal processing can be done within the sensor, shielding it from outside interference. This makes it possible to work with signals of the order of tens of Pascals without much difficulty, something that traditional sensors with external circuitry would be challenged to do.
The sensor may, for example, be used in a breath actuated dry powder inhaler. These inhalers may be configured such that inhalation by the user through the mouthpiece results in an airflow through the device entraining dry powder medicament. The inhalation also may result in another airflow entering the inhaler from outside. The inhaler may comprise a swirl chamber in which the two airflows collide with one another and the chamber walls to break down aggregates of the dry powder medicament for more effective delivery.
For example, the sensor may be used in a breath actuated pressurized aerosol inhalers. These inhalers comprise a means for releasing a measured dose of medicament, the releasing means comprising a means for priming the device by applying a preload capable of actuating delivery means, a means for applying a resisting pneumatic force capable of preventing actuation of the delivery means and a release device capable of freeing the resisting pneumatic force to allow the preload to actuate the delivery means and dispense the medicament. The pneumatic resisting force can be established by mechanisms comprising, for example, a diaphragm, a piston cylinder, a bellows or a spring. Inhalation through a valve or past a vane mechanism allows the preload to actuate an aerosol valve to release medicament.
Adherence could be monitored for such inhalers by determining when the device is primed and/or when the aerosol valve opens. Again, the introduction of a MEMS barometric pressure sensor anywhere in the airflow path through the inhaler or anywhere in fluid communication with the airflow path, in combination with means for determining when the device has been primed and/or when the aerosol valve opens, may enable compliance monitoring.
Priming the device may result in both a preload being applied to the delivery means and a load being applied to an electronic switch. This switch may be connected to an input of the processor such that the processor receives an electronic pulse when the device is primed. Alternatively or additionally, an electronic switch may be arranged to be actuated by motion of the aerosol valve or of the valve or vane mechanism preceding the aerosol valve. This switch may be connected to an input of the processor such that the processor receives an electronic pulse when aerosol is released to the flow channel through which the patient inhales. The switch may be, for example, mechanical, optical, proximity based or an accelerometer.
It should be noted that because MEMS barometric pressure sensors respond to environmental barometric pressure, which can change over time, attention should be paid to the initial reading that any subsequent sensor output signal analysis is based upon. An automatic zero reading (e.g., tare) may be performed immediately prior to monitoring any inhalation signal. While it is possible for this value to change over time in response to changes in local environmental barometric pressure, it may not be expected to cause any issues if a treatment is completed within a few minutes. A second barometric chip may be used to keep track of barometric activity, allowing the primary chip to be used exclusively for breath detection.
The point at which dosing is complete (e.g., where lung volume peaks) may correspond to the point at which flow reverses direction. Thus, the processor may make a determination that dosing is complete when the data from the pressure sensor indicates that flow direction has reversed.
Not all processing needs to be done by the module. Any or all processing may be offloaded to an external data processing device. A wireless scheme (for example comprising a BLE module) may be used to transmit patient flow profiles to an app which could then calculate specific breathing parameters. The inhaler may thereby offload the processing required for such a task to, for example, a smart phone processor. This may facilitate the smallest form factors possible for the inhalers. A further advantage of this approach may be that software running on a smart phone may be changed more readily than software running on an inhaler.
The processor may provide the information gathered by the sensor and processed by the processor to a remote device through a transceiver. The transceiver is described in detail below. Although the examples below use wireless communication, an inhaler may communicate via other modes, including use of a wire.
The addition of transceiver may make it possible to monitor patient adherence and compliance and communicate such information, for example including patient flow profiles, to a user device, such as a smart phone, tablet, or computer. The information may be sent to a server, either directly from an inhaler or from a user device. From a user device data can be communicated to a caregiver's device, for example a doctor's personal computer (PC). This could be done using a wired connection, for example via a Universal Serial Bus (USB) port. Using wireless technology, it may be possible to communicate results to the outside world without interrupting the product housing in any significant way. Suitable wireless technologies could include, for example, WiFi technologies such as IEEE 802.11, Medical Body Area Network (MBAN) technologies such as IEEE 802.15, Near Field Communication (NFC) technologies, mobile technologies, such as 3G and 4G, and Bluetooth™ technologies, such as Bluetooth™ Low Energy (BLE). A wireless transceiver, for example in the form of a BLE chip, may be connected to the miniature sensor or integrated with it.
Such wireless connectivity may be used, for example, to report device actuation and/or sensed inhalation with date and time stamps in real time. This data may be processed externally and if the result of such processing is that it is determined that a prescription should be refilled, an alert may be sent to the patient and/or caregiver and/or pharmacist. Alerts may be provided via one or more user interfaces of the inhaler (for example an LED and/or a buzzer) or via text message or email. As an example, if no dosing report is received within a predetermined period following a scheduled dosing time, a reminder may be sent to the patient and/or caregiver. Alerts may also be generated for example if use frequency is exceeding a safe threshold.
The compliance module may communicate directly or indirectly with one or more of: a user device (such as a mobile phone e.g. a smartphone, a tablet, a laptop or a desktop computer) of a patient, or of a caregiver (such as a doctor, nurse, pharmacist, family member or carer), a server e.g. of a health service provider or inhaler or drug manufacturer or distributor or a cloud storage system. Such communication may be via a network such as the Internet and may involve a dedicated app, for example on the patient's smartphone.
Compliance monitoring means (such as one or more sensors, e.g. a device actuation sensor such as a mechanical switch to detect adherence and compliance reporting means, e.g. a miniature pressure sensor to detect sufficient flow for proper dose delivery) and compliance reporting means (such as a wireless transmitter or wired output port) may be included in a single module. This module may be sold as a separate inhaler accessory/upgrade for attachment to an existing or slightly modified design of inhaler. The compliance monitoring module may be incorporated into the inhaler during manufacture. The compliance monitoring module may be in a single physical unit. The compliance monitoring module may be in multiple units. In the case of an inhaler accessory version, the module may consist of one or more attachable units. In the case of a module incorporated into an inhaler, the individual components may be located in any suitable locations in or on the inhaler and need not be grouped together or connected any further than required for them to function.
When the inhaler detects that the pressure measurement of the inhaler exceeds a predetermined amount at 835 (e.g., which may be indicative of a full dose of medication being administered to the user), the indicators A and B may be in state A4 and B4 at 840. For example, the indicator A may illuminate in state A4 and the indicator B may illuminate in state B4. If the inhaler detects that the cover is closed at 845, then the indicators A and B may be in state A1 and B1 at 810. For example, the indicators A and B may be off in states A1 and B1. In one or more embodiments, 825 and 830 may be omitted such that the inhaler may proceed to 835 from 820.
Example state diagrams may include the states A1, B1, A2, B2, A3, B3, A4, and B4 of the indicators A and B being in any combination of an off state, an on state, and/or a flashing state. Moreover, if the indicator is a light, the on state and/or flashing state may be characterized by the light being illuminated in one or more of a plurality of colors. The indicator may use different patterns of flashing. For example, example state diagrams are provided in Table 1 below:
In example 1, indicator A is off in state A1 (e.g., when the cover is closed), on in state A2 (e.g., to indicate that a dose is ready), on in state A3 (e.g., while the user is inhaling), and on in state A4 (e.g., when the dose has been administered). In example 1, indicator B is off in states B1, B2, and B3, and on in state B4. In example 2, indicator A is off in state A1, and on in states A2, A3, and A4. In example 2, indicator B is off in state B1, flashing in states B2 and B3, and on in state B4. In example 3, indicator A is off in state A1, and on in states A2, A3, and A4. In example 3, indicator B is off in state B1, on in states B2 and B3, and off in state B4. In example 4, indicator A is off in state A1, and on in states A2, A3, and A4. In example 4, indicator B is off in state A1, flashing in state B2, on in state B3, and off in state B4. There may be other methods of indicating the states. For example, the indicators may include multi-light and/or multi-color configurations.
An inhaler (e.g., the inhaler 100) may have a single indicator, which for example, may be a light. The indicator light may have multiple colors and/or multiple modes of indication. For example, the indicator light may be on, off, flashing, and/or illuminate in multiple colors. The indicator light may use different patterns of flashing.
When the inhaler detects that the pressure measurement of the inhaler exceeds a predetermined amount at 935 (e.g., which may be indicative of a full dose of medication being administered to the user), the indicator may be in state 4 at 940. For example, the indicator may illuminate in state 4. If the inhaler detects that the cover is closed at 945, then the indicator may be in state 1 at 910. For example, the indicator may be offin state 1. In one or more embodiments, 925 and 930 may be omitted such that the inhaler may proceed to 935 from 920.
The indicator may be on, off, flash, and/or illuminate in different colors to indicate different states. For example, indicator may indicate state 2 with green and state 4 with blue.
Example state diagrams may include the states A1, B1, A2, B2, A3, B3, A4, and B4 of the indicator being in any combination of an off state, an on state, and/or a flashing state. Moreover, if the indicator is a light, the on state and/or flashing state may be characterized by the light being illuminated in one or more of a plurality of colors. The indicator may use different patterns of flashing. For example, example state diagrams are provided in Table 2 below:
In example 1, the indicator is off in state A1 (e.g., when the cover is closed), flashing in state 2 (e.g., to indicate that a dose is ready), flashing in state 3 (e.g., while the user is inhaling), and on in state 4 (e.g., when the dose has been administered). In example 2, the indicator is off in state 1, and on in states 2, 3, and off in state 4. In example 3, the indicator is off in state 1, on in a first color in states 2 and 3, and on in a second color in state 4. In example 4, the indicator is off in state A1, on in a first color in state 2, flashing in state 3, and on in a second color in state 4. In example 5, the indicator is off in states 1, 2, and 3, and on in state 4. In example 6, the indicator is off in state 1, on in a first color in state 2, on in a second color in state 3, and on in a third color in state 4. There may be other methods of indicating the states. For example, the indicators may include multi-light and/or multi-color configurations.
The inhaler (e.g., the inhaler 100) may determine that the reservoir is empty, for example, via a dose counter. The dose counter may be mechanical and/or electrical. For example, the electronics module of the inhaler may determine that the reservoir is empty. In an example, the dose counter may be configured to count down the number of available doses based on actuations of the cover, which for example, may correspond to dispensing of medication into a dosing cup. When the inhaler determines that the reservoir is empty and when the cover is subsequently opened, the inhaler may leave the indicator(s) in the off state. This, for example, may indicate to the user that the inhaler is not ready for inhalation because the inhaler is out of medication. The inhaler may indicate that the reservoir is empty using one or more of the indication techniques described herein (e.g., sold light, colored light, flashing light, one or more indicators, etc.).
Although not illustrated, the examples provided herein (e.g., with reference to
Although described primarily with reference to visual indicators (e.g., one or more lights and/or light states), one or more of the embodiments/examples described herein may comprise other indicators. For example, the indicators may comprise visual indicators (e.g., one or more lights and/or light states), audible indicators (e.g., one or more buzzers/speakers and/or sounds), and/or haptic feedback indicators (e.g., one or more haptic feedback devices and/or haptic feedback states/operations).
This application claims the benefit of U.S. Provisional Application No. 62/043,120, filed Aug. 28, 2014, the contents of which are incorporated by reference herein.
Number | Date | Country | |
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62043120 | Aug 2014 | US |
Number | Date | Country | |
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Parent | 15506171 | Feb 2017 | US |
Child | 16571587 | US |