Patent Application
20210085903
Not applicable
The present invention relates generally to systems for diagnosing chronic obstructive pulmonary disease (COPD) and other lung diseases using the forced oscillation technique (FOT) and other lung function tests and, more particularly, to a patient mouthpiece especially designed to enhance the patient interface of the system and cheek supports that are designed for optional use with the mouthpiece.
COPD is currently the fourth-most frequent cause of death in humans. The spirometry test is typically used to evaluate respiratory obstruction in COPD. Although considered the gold standard test, spirometry has the disadvantage of requiring great effort and great cooperation from patients, which can result in variation in the quality of test results and performing the test on some patients can be difficult, especially with infants.
In U.S. Pat. No. 5,318,038 to Jackson et al, there is described an infant respiratory impedance measuring apparatus in which the power amplifier is used to drive a loud speaker to superimpose a pulsatile variation in the pressure of air being breathed by a patient. The expiratory flow and pressure signals from transducers are amplified, filtered and applied to a program computer for analysis.
In the Jackson '038 patent to interface the hardware components to the patient, a mask covering the nose and mouth of the patient is employed.
It has been found that masks of the type described may lead to inaccuracies in the computation of lung impedance due to its excessive dead space. As is recognized in the prior art, a mouthpiece should be shaped so as to allow a patient to maintain a relatively airtight seal between the lips and the exterior thereof and that it could include a disposable filter to inhibit cross-contamination between patients of bacterial or viral infections. It is also important that the patient not obstruct the airflow with their tongue or clenched teeth.
It is accordingly a principle object of the present invention to provide an improved mouthpiece for use with equipment for measuring the respiratory impedance of a patient's lungs.
It has also been found that distortion of a subject's cheeks due to the pressure impulses imparted by the audio speaker and superimposed on the patient's airflow can adversely impact the accuracy of the impedance measurement in that the oral cavity will function as a shunt of the pressure and alter the results.
In the system illustrated, the speaker produces pressure waves which become superimposed with the air flows as the patient inhales and exhales. Pressure and flow transducers measure changes in response to the pressure waves introduced into the respiratory airflow, as well as changes in the flow rate of airflow. From this, the mechanical impedance (Z) of the patient's lung can be computed as the ratio of pressure (P) to flow (V) or Z=P/V. The speaker can be driven at various frequencies during the test and the computation of the impedance is made for each.
The foregoing advantages over the prior art are achieved by providing an improved patient mouthpiece consisting of an integrally molded, silicone or elastomer rubber device having a round tubular portion that is designed to fit over a tubular or oval input/output member of a respiratory antibacterial filter device. Projecting out from the exterior wall of the tubular portion is a pair of wedge-shaped protuberances to which is attached proximally to a pair of laterally spaced, generally rectangular bite blocks. Completing the device and joined to the bite blocks by downwardly, and inwardly slanted bridge members is a generally rectangular tongue depressor.
The design is such that when the bite blocks are placed between a persons teeth on his or her upper and lower jaw, it prevents the teeth from closing in front of the lumen of the tubular portion and, the tongue depressor resides atop the person's tongue, preventing it also from partially occluding the lumen of the tubular portion of the mouthpiece and thereby altering the airway resistance. At the same time, the wedge members serve to create a seal with the natural shape of the subject's lips.
An attachment is provided for the mouthpiece that serves to stabilize the subject's cheeks. A cheek stabilizer is found to be important when conducting the FOT test procedure. The attachment comprises a toroidal ring designed to fit about and be supported on the tubular portion of the mouthpiece and provides support to a pair of cheek-engaging members that are releasably coupled to the toroidal ring at diametrically located positions. Cheek-engaging members can be joined to the ring at a plurality of locations so as to afford a selection of spacings between the cheek-engaging members, thereby accommodating a variety of patient's face dimensions.
The foregoing features, objects and advantages of the invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, especially when considered in conjunction with the accompanying drawings in which like numerals in the several views refer to corresponding parts:
This description of the preferred embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description of this invention. In the description, relative terms such as “lower”, “upper”, “horizontal”, “vertical”, “above”, “below”, “up”, “down”, “top” and “bottom” as well as derivatives thereof (e.g., “horizontally”, “downwardly”, “upwardly”, etc.) should be construed to refer to the orientation as then described or as shown in the drawings under discussion. These relative terms are for convenience of description and do not require that the apparatus be constructed or operated in a particular orientation. Terms such as “connected”, “connecting”, “attached”, “attaching”, “join” and “joining” are used interchangeably and refer to one structure or surface being secured to another structure or surface or integrally fabricated in one piece, unless expressively described otherwise.
In
Mouthpiece 10 is seen to comprise a molded plastic member, preferably, but not necessarily, of a silicone rubber and having a tubular portion 14 with a circular cross section whose ID is sized to receive a tubular member 16 of the filter 12 therein. Tubular member 12 is integrally molded with a case 18 containing an anti-bacterial filter media specifically designed to permit gas flow therethrough while capturing any particulate matter that may be present in the air stream being inhaled and exhaled by a person undergoing FOT test.
Integrally molded with and extending laterally outward from an outer wall of the tubular portion 14 is a pair of wedge-shaped projections 20. The shape of the wedge-shaped projections 20 can best be seen in the detailed drawing of
The wedge-shaped projections 20 are integrally joined with a corresponding pair of cylindrical block segments as at 22 and 24. Block segments 22 and 24 are of a predetermined height and thickness dimension as seen in
Suspended from the blocks 22 and 24 by flexible bridge segments 26 and 28 (
With continued reference to
The wedge-shaped projections 20 on the mouthpiece function to help seal the subject's lips at the corners of the subject's mouth when the subject has clamped the bite blocks 22 and 24 between his or her jaws.
Turning next to
Without limitation, the annular ring 31 and the cheek-engaging members 44 and 46 are preferably a rigid plastic, such as a polycarbonate. The polycarbonate may be sandwiched between layers of neoprene pads for affording greater comfort to the user.
In use, the ring 31 with its cheek-engaging members 44 and 46 is mounted on the mouthpiece assembly of
The mouthpiece of the present invention is adapted to be coupled to a FOT measuring instrument, such as a Resmon™ PRO Full device to measure the mechanical properties of a subject's lung using FOT. This device is available from MGC Diagnostics, Inc. of Vadnais Heights, Minn.
This invention has been described herein in considerable detail in order to comply with the patent statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use embodiments of the example as required. However, it is to be understood that the invention can be carried out by specifically different devices and that various modifications can be accomplished without departing from the scope of the invention itself.
This application is a non-provisional application of Application No. 62/905,801, filed Sep. 25, 2019, and claims priority from that application which is also deemed incorporated by reference in its entirety in this application.
| Number | Date | Country | |
|---|---|---|---|
| 62905801 | Sep 2019 | US |
