The present disclosure pertains to oscillometry measurements (a.k.a., forced oscillation technique (FOT)) and equipment as used in the assessment and monitoring of respiratory mechanics and pulmonary function for example in the context of asthma or chronic obstructive pulmonary disease (COPD).
Unlike conventional techniques to measure lung functions such as spirometry or peak flow, oscillometry does not rely on a voluntary effort by the user (meaning, in this context, the subject or patient to be measured, in contrast to a person overseeing the measurement) to perform a specific manoeuvre. Rather, oscillometry measurements are obtained during regular quiet breathing, making the technique natural for the user.
During an oscillometry measurement, a gentle oscillatory waveform generated by an oscillometry device is superimposed on the quiet breathing of the user. The frequencies of interest contained in the oscillatory waveform are situated above the power spectrum of the spontaneous breathing, so that the oscillatory and breathing components contained in the recordings can be separated using numerical techniques such as Fourier transforms and time-frequency analysis.
One constraint associated with oscillometry measurements is that the users, typically breathing through a mouthpiece, must support their cheeks and mouth floor with their hands to ensure that the oscillatory energy generated by the oscillometry device reaches the lungs and does not get lost in the softer, compliant tissues of the upper airways. Expressed in more technical terms, the hands must be used to increase the shunt impedance presented by the upper airway walls that would otherwise be too low and short-circuit the oscillation.
Because both of the user's hands are used to support the left and right cheeks, the user may not be able to simultaneously hold a handheld, portable oscillometry device. Therefore, oscillometry devices must be either mounted to a physical support such as a desktop or trolley, or if portable, an independent operator is required to hold the device during the measurement while the users support their cheeks.
Consequently, the existing portable devices may not lend themselves to self-assessment “anywhere”, i.e., in a manner adapted to the user's lifestyle, as is the case for example for blood pressure monitoring. Another person is often needed to hold and operate the device, therefore such measurements can no longer be considered self-assessment.
European Patent No. 2598026 describes plates of slightly concave substantially triangular shape which are positioned on the user's cheeks to exert a slight pressure, intrinsic of the plates, and hold them still. The plates are intended to replace manual cheek support, which means that they must exert a pressure onto the user's cheeks that is similar to the pressure that would be exerted by the user's hands during manual cheek support. These plates possess significant rigidity in a direction normal to the cheek skin surface. The weight of the plates is supported by their attachment to the device, which must in turn be supported by an appropriate structure or independent operator.
An aim of the present disclosure is to provide a self-use oscillometry device that addresses issues related to the prior art.
A further aim of the present disclosure is to provide a portable oscillometry device that may be physically supported by a user without compromising, or even while ensuring proper cheek support and device positioning.
In accordance with a first embodiment of the present disclosure, there is provided an oscillometry device comprising: a casing, a user portion forming a conduit entering into the casing, the conduit adapted to receive a breath of a user, an oscillometry measurement system operatively connected to the conduit in the casing and adapted to produce oscillometry measurement signals from the breath of the user, and a user support interface projecting from the casing in a common direction with the user portion, the user support interface vertically supporting the oscillometry device relative to a user when the user has his or her mouth on the user portion, the user support interface being made of a flexible deformable material.
Further in accordance with the first embodiment, for instance, the user support interface includes a pair of handles projecting from the casing.
Still further in accordance with the first embodiment, the handles are elongated strips of the flexible deformable material.
Still further in accordance with the first embodiment, the elongated strips form loops.
Still further in accordance with the first embodiment, the loops are sized to receive four fingers or a palm of a user.
Still further in accordance with the first embodiment, for instance, at least one finger loop is on at least one of the lateral surfaces of the elongated strips.
Still further in accordance with the first embodiment, for instance, at least one pressure sensor is on at least one of the handles producing a signal indicative of a pressure applied thereon.
Still further in accordance with the first embodiment, for instance, at least one inertial sensor on the casing produces a signal indicative of an orientation of the oscillometry device.
Still further in accordance with the first embodiment, for instance, the user support interface includes at least one head strap.
Still further in accordance with the first embodiment, for instance, the handles have a height of at most 4.0 cm in a face contacting end.
Still further in accordance with the first embodiment, for instance, a height to thickness ratio for the face contacting end of the handles is of at least 10.
In accordance with a second embodiment of the present disclosure, there is provided an oscillometry device comprising: a casing, a user portion projecting in a user direction and forming a conduit entering into the casing, the conduit adapted to receive a breath of a user, the user portion having a central axis, the central axis being normal to a reference plane of the user portion, the conduit plane being at an end of the user portion in the user direction, an oscillometry measurement system operatively connected to the conduit in the casing and adapted to produce oscillometry measurement signals from the breath of the user, and a user support interface projecting from the casing and having handles extending beyond the reference plane in the user direction, the user support interface vertically supporting the oscillometry device relative to a user when the user has his or her mouth on the user portion, the user support interface being made of a flexible deformable material, the handles being positioned laterally of the central axis and vertically located at least partially in a range of +5 cm to −5.0 cm of the central axis.
Further in accordance with the second embodiment, for instance, the handles are elongated strips of the flexible deformable material.
Still further in accordance with the second embodiment, for instance, the elongated strips form loops.
Still further in accordance with the second embodiment, for instance, the loops are sized to receive four fingers or a palm of a user.
Still further in accordance with the second embodiment, for instance, at least one finger loop is on the lateral surfaces of the elongated strips.
Still further in accordance with the second embodiment, for instance, at least one pressure sensor on the handles produces a signal indicative of a pressure applied thereon.
Still further in accordance with the second embodiment, for instance, at least one inertial sensor on the casing produces a signal indicative of an orientation of the oscillometry device.
Still further in accordance with the second embodiment, for instance, the handles are part of a head strap.
Still further in accordance with the second embodiment, for instance, the handles have a height of at most 4.0 cm in a face contacting end.
Still further in accordance with the second embodiment, for instance, a height to thickness ratio for the face contacting end of the handles is of at least 10.
Still further in accordance with the second embodiment, for instance, ends of the handle extend beyond the reference plane by at least 3.0 cm.
Still further in accordance with the second embodiment, for instance, ends of the handle extend are located at a distance from 3.0 cm to 12.0 cm beyond the reference plane.
Referring to the drawings and more particularly to
Referring to
The conduit 20 has a user port 40 at a free end. The user port 40 may or may not be releasably fitted with a suitable interface to the user's airway opening, such as a mouthpiece. A flow meter 50 is located between the oscillatory flow source 30 and the user port 40, and is in fluid communication with the conduit 20, to measure the airflow into and out of the user's airway opening. The fluid communication may be qualitied as operative connection, in that the airflow into the user port 40 and conduit 20 reaches the oscillometry measurement system, in operative connection. The flow meter 50 may include screen, honeycomb, ultrasonic, variable orifice or venturi pneumotachographs, just to name a few. Between the flow meter 50 and the user port 40 is a pressure meter 51 to measure the pressure proximal to the user's airway opening.
Respiratory system input impedance and other indices of respiratory mechanics and lung function may be calculated from the data recorded by the flow meter 50 and the pressure meter 51, and a dynamic characterization of the air passages between the user and the site of measurement, i.e. the user port 40 and the portion of the conduit 20 situated between the user port 40 and the flow meter 50, may be used to enhance the accuracy of the impedances and indices calculated.
The conduit 20 may further be in fluid communication with an atmosphere port 60 with a deterministic impedance to air flow that is sufficiently low to prevent undue loading of the user's breathing, but sufficiently high to prevent short-circuiting of the oscillatory waveform.
The device 10 may further include all required electronics 70, including at least one processing module 71 with one or more processors with memory for data storage, communication facilities etc., peripherals 72 such as A/D and D/A converters, signal amplifiers, filters and oscillator driver, and an energy source 73 such as a battery, i.e. all components that are needed to generate the oscillation, record the measurements, store the results and transmit them to another device such as a computer, tablet, smart phone, telemedicine server or central database, just to name a few. The processing module 71 may be in the form of a non-transitory computer-readable memory communicatively coupled to the processing unit and comprising computer-readable program instructions executable by the processing unit for performing and asses oscillometry measurements. In another embodiment, the device may communicate wirelessly with a computer or portable electronic device, and some of the processing or user interface functionality described above may be located on this portable electronic device.
All of the above components are physically firmly attached to each other in the compact and sufficiently lightweight enclosed casing 80, which is assembled for use but which may be configured to be disassembled for cleaning and maintenance. This may allow access to the oscillometry measuring system, i.e., the various components described above, including hardware, electronics and software, operation oscillometry measurements. Further attached to the casing 80 is a user support interface 90. According to an embodiment shown in
Due to the location of the user support interface 90 relative to the casing 80 and to the user port 40, the hands of the self-user are positioned face to face with his or her respective cheeks, for the hands to be ergonomically applied against the cheeks and mouth floor when the self-user's mouth and/or nose is connected to the user port 40 (e.g., directly on the port 40 or on the mouthpiece). In this arrangement, the grips 90 (or portions thereof) are sandwiched between the hands and the cheeks and/or mouth floor, so that the weight of the device 10 is supported by the grips 90 or like user support interface. The grips 90 may be sufficiently flexible, for example in elastic deformation, in the dimensions normal to the skin surface in order to adapt to the unique shape of each user's face. The grips 90 may also be made of a material with shape retention capacity, i.e., the grips 90 can retain the shape they are deformed to, with a range of deformation. The grips 90 may be sufficiently rigid in a vertical dimension to support the weight of the device 10 and offer a stable position to the casing 80 relative to the user's mouth when supported in the manner shown in
In accordance with an embodiment, the device 10 may be adequately supported by a single one of the grips 90. In accordance with another embodiment, the user support interface(s) 90 project in a same direction as the user port 40, and are vertically positioned on the casing 80 as a function of the position of the user port 40. For example, when the device 10 is in the orientation of
Accordingly, the user support interface 90, such as the grips of
In another way to describe the arrangement of the user support interface, the user port 40 has a central axis X, and a reference plane P at the end of the user port 40 closest to the user, the central axis X being normal to the reference plane P of the user port 40 (
Referring to an embodiment of the device 10 shown in
In the embodiment of the device shown in
In another embodiment, the user port 40 may include a concave space below the mouthpiece in which the user's tongue can comfortably be placed. Such a tongue space may be fitted with a sensor that can detect and confirm proper tongue placement, so that proper tongue placement may be used as a precondition or trigger to start a measurement. This feature may be in an oscillometry device or other lung function measuring device that is not necessarily self-use.
In another embodiment shown in
In another embodiment shown in
In another embodiment shown in
In another embodiment shown in
In accordance with an embodiment, the oscillometry device 10 has two or more of the items shown in
In another embodiment, a cradle provided with the oscillometry device 10 may be shaped such that when the oscillometry device 10 rests on the cradle, the user support interface 90 is(are) naturally positioned such that the device 10 can easily be picked up by the user support interface(s) 90. The cradle may include means to charge the oscillometry device 10, which may include means for inductive charging, among other options.
In another embodiment of the device, the user support interface may be replaced by a head interface with elastic bands that are placed around the user's head so that the oscillometry device 10 can be worn like a mask, permitting entirely hands-free operation, e.g. to measure users on a treadmill or stationary bicycle during exercise testing. This feature may be in an oscillometry device that is not necessarily self-use.
The present applications claims the priority of U.S. Patent Application No. 62/731,424, filed on Sep. 14, 2018, and incorporated herein by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/CA2019/051308 | 9/16/2019 | WO | 00 |
Number | Date | Country | |
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62731424 | Sep 2018 | US |