Abstract:
An improved incentive spirometer having a modular goal recording counter (GRC) releasably attached thereto for enabling a patient to view the number of times a predetermined respiratory therapy inhalation exercise has been properly performed. The GRC also includes a coaching lamp to facilitate the patient&#39;s maintaining the desired flow rate of inspiratory air for a predetermined time period. The GRC is operational in one mode to initiate a count of the number of successful exercise completions beginning with “0”, and in another operational mode to retain and recall the count of the number of successful exercises previously completed. The operation of the GRC is controlled by a microcontroller which controls the operation of the GRC and the electrical circuit connected thereto is designed to minimize the power requirements of the components when the GRC is placed in the retain and recall mode of operation.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates in general to respiratory therapy devices and, in particular, to an improved incentive spirometer including a goal recording counter (GRC) which monitors the number of times a patient has completed a particular usage of the spirometer. 
     More specifically, but without restriction to the particular embodiment and/or use which is shown and described herein for purposes of illustration, this invention relates to an incentive spirometer having a detachable GRC which when applied to the spirometer records the number of times a user has successfully completed a particular breathing exercise. The spirometer also includes an oxygen inlet to facilitate the introduction of oxygen into the device without the oxygen effecting the monitoring of a patient&#39;s use of the device, and an integral information display receptacle to enable written information to be displayed while the spirometer is in use. 
     2. Description of Related Art 
     The use of incentive spirometers for respiratory care and treatment is well known. However, one of the desirable features for inclusion with such spirometers would be the incorporation of a counter to monitor the number of times that a user or patient has successfully completed a particular breathing exercise that has been prescribed for the patient&#39;s therapy or treatment. While certain spirometers have been designed to monitor functional operations, such equipment incorporates the monitoring function as an integral component of the spirometer or device with which the counter is used, or are actuable by the action of the user or patient when using the spirometer, thereby effecting the accuracy of the manner in which a patient is using the device. Accordingly, it would be desirable that such a monitor or counter be capable of accurately recording the number of times a patient or user has completed a particular exercise, but not interfere with or utilize the air stream between the patient and the breathing device. Incentive spirometers are utilized to monitor a patient&#39;s breathing, and to provide a controlled exercise for a patient&#39;s lungs and associated breathing apparatus. While the use of a counting device to record the number of times a patient has successfully completed a prescribed exercise is very advantageous when using an incentive spirometers, the interference with the air stream between the patient and the device can effect the calibration of the incentive spirometer, and gives the patient false feedback readings by which a patient monitors their proper use of the device. The present invention includes a removable Goal Recording Counter which is not an integral part of the spirometer and does not interfere with the calibration of the device or the patient&#39;s use of the spirometer. 
     SUMMARY OF THE INVENTION 
     It is an object of this invention to improve incentive spirometers. 
     Another object of this invention is to provide a spirometer which includes a GRC for monitoring or recording the number of times a patient has successfully completed a prescribed breathing exercise without interfering with the normal operation of the spirometer. 
     A further object of this invention is to provide a spirometer which includes a GRC for monitoring or recording the number of times a patient has successfully completed a prescribed breathing exercise without interfering with the calibration of the spirometer. 
     Still another object of this invention is to provide a spirometer which includes a GRC for monitoring or recording the number of times a patient has successfully completed a prescribed breathing exercise which is not an integral component of the spirometer, but can be removed therefrom for use with a separate device. 
     Yet another object of this invention is to provide a spirometer which includes a GRC for monitoring or recording the number of times a patient has successfully completed a prescribed breathing exercise and informing a patient that the exercise has been properly performed. 
     These and other objects are attained in accordance with the present invention wherein there is provided an improved incentive spirometer including a selectively removable Goal Recording Counter adapted to be positioned on the spirometer without interfering with the fluid communication between a patient and the spirometer to record the number of occurrences of a proper breathing exercise performed by a patient and to inform the patient when a predetermined exercise has been properly performed. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     Further objects of this invention, together with additional features contributing thereto and advantages accruing therefrom, will be apparent from the following description of a preferred embodiment of the present invention which is shown in the accompanying drawings with like reference numerals indicating corresponding parts throughout and which is to be read in conjunction with the following drawings, wherein: 
     FIG. 1 is a frontal perspective view of the improved incentive spirometer with a GRC supported thereon in a position to record the occurrence of a properly performed exercise and to inform the patient when the exercise has been properly performed; 
     FIG. 2 is a frontal elevational view of the improved incentive spirometer illustrated in FIG. 1 with portions broken away to better illustrate the internal construction thereof; 
     FIG. 3 is a rear elevational view of the improved incentive spirometer illustrated in FIG. 1 with portions broken away to better illustrate the internal construction thereof; 
     FIG. 4 is a top elevational view of the improved incentive spirometer illustrated in FIG. 1 with portions broken away to better illustrate the internal construction thereof; 
     FIG. 5 is a front elevational view of the Goal Recording Counter illustrated in FIG. 1 to better illustrate the features thereof; 
     FIG. 6 is a left side elevational view of the Goal Recording Counter illustrated in FIG. 5 to better illustrate the mechanism for connection to the spirometer body; 
     FIG. 7 is a right side elevational view of the Goal Recording Counter illustrated in FIG. 5 to better illustrate the mechanism for connection to the spirometer body; 
     FIG. 8 is a top elevational view of the Goal Recording Counter illustrated in FIG. 5 to better illustrate the mechanism for connection to the spirometer body; 
     FIG. 9 is a partial rear view of the Goal Recording Counter illustrated in FIG. 5 taken along line  9 — 9  to better illustrate the features thereof; 
     FIG. 10 is a logic block diagram or flow chart to better illustrate the manner in which the Goal Recording Counter will record the occurrence of a properly executed breathing exercise and to display to the user when the breathing exercise has been properly performed; and 
     FIG. 11 is an electrical schematic of the microcontroller and circuit incorporated into the GRC for recording and displaying the occurrence of a properly executed breathing exercise and to display to the user when the breathing exercise has been properly performed. 
    
    
     These and additional embodiments of the invention may now be better understood by referring to the following detailed description of the invention wherein the illustrated embodiments are described. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Throughout this description, the preferred embodiment and examples shown should be considered as exemplars, rather than limitations on the apparatus and methods of the present invention. 
     Referring now to the drawings, there is shown an incentive spirometer  100 , having a handle portion  20 , a base portion  30 , a volume chamber portion  50 , a goal recording counter (GRC)  60  and a monitoring portion  80 . The handle portion  20  provides a convenient manner for holding and carrying the device, and for attaching the device to a bed, for example, where it can be readily accessible. The base portion  30  provides a platform upon which the device rests, and an integral information display receptacle for containing information such as the written instructions for use of the device which can be conveniently observed by a patient from the top or the bottom of the device when the device is in use. The volume chamber portion  50  provides a predetermined volume against which a patient&#39;s respiratory system is exercised for a determinable volumetric capacity to obtain the benefits of this therapy. The GRC  60  provides a readily attachable and removable display to inform a patient of the number of times a predetermined breathing exercise has been properly performed and a display to inform the patient when a predetermined breathing exercise has been properly performed. The monitoring portion  80  provides a visual display for a patient to determine the correct flow of inspiratory air to be applied by the patient&#39;s respiratory system during therapy, and in cooperation with the GRC  60  and volume chamber portion  50 , permits the patient to determine the quantity of inspiratory air which has been drawn into the patient&#39;s lungs at the correct flow rate. 
     As best illustrated in FIGS. 1,  2 ,  3  and  8 , the monitoring portion  80  includes an inlet port  81  formed as an opening in a front wall  83  of the monitoring portion through which a patient draws inspiratory air by means of a mouthpiece (not shown) connected to a flexible Popple tube  93 . The tube  93  is sized to be securely positioned over the connecting port in which is carried a one-way valve  82  to permit a patient to draw inspiratory air through the mouthpiece  91 , but which blocks the passage of expiratory air from passing back into the device. The monitoring portion  80  permits the patient to monitor the inspiratory air flow rate being applied by the patient&#39;s respiratory system during therapy, and in cooperation with the GRC  60  and volume chamber portion  50 , to monitor the volume or quantity of air being inhaled. 
     To this end, the monitoring portion  80  includes an indicator  85  of a predetermined weight, preferably approximately 0.5 grams, which is vertically moveable between two parallel guide rails  86  (best shown in FIG. 3) which are formed between the front wall  83  and a back wall  84  of the monitoring portion  80  defining an indicator channel  75 . The channel  75  in which the indicator  85  is vertically moveable, formed between the front and back walls  83 ,  84  and the guide rails  86 , is in fluid communication with the inspiratory air inlet port  81  so that as a patient draws inspiratory air from the mouthpiece  91 , the flow of air will cause the indicator  85  to rise in the channel so formed. A pair of air channels  72  and  78  are formed in the monitoring portion  80  to provide fluid communication, respectively, between the inlet port  81  and the indicator channel  75 , and the inlet port  81  and the volume chamber portion  50 , for a purpose to be hereinafter described in detail. A pair of indicator stops  85   a  are positioned to extend across the channel  75  to define the upper and lower limits of travel of the indicator  85  within the channel. 
     In the preferred embodiment, a window  88  or other suitable indicia such as target or demarcation lines are formed on the front wall  83  to delineate a positional range within which a patient is to keep the indicator  85  when inhaling. In this manner, a patient can monitor the proper rate of flow of the inspiratory air which is to be drawn into the respiratory system, by keeping the indicator  85  within the target area  88  of the indicator. Alternatively, when the GRC  60  is attached to the spirometer adjacent to the volume chamber portion  50 , a count is maintained and an indicator lamp is illuminated for a predetermined time period when the proper rate of flow of inspiratory air is drawn into the respiratory system, and “coaches” patients to hold their breath for a particular desired period of time so that the exercise is properly performed. 
     On the back wall  84 , a connecting oxygen inlet port  94  is formed to receive a connection from a source of oxygen. The oxygen inlet port  94  extends from the rear of the back wall  84 , through the back and front walls  84  and  83  of the monitoring portion  80 , and terminates at an oxygen discharge outlet  97  positioned adjacent to the inlet  81  through which a patient draws inspiratory air. The oxygen discharge outlet  97  is positioned such that the flow of oxygen is directed across an inlet  87  through which air is drawn into the device when the patient inhales through the mouthpiece  91 , and not directed into the inlet  87 . In this manner, the oxygen being supplied will not effect the patient created air flow applied to the device when in use. A cowling  98  partially surrounds the air inlet  87  to facilitate oxygen being drawn into the inlet  87  during use by a patient, without the flow of oxygen effecting a patient&#39;s use of the device or the monitoring of the rate of inspiratory air flow applied by a patient when using the device. 
     The volume chamber portion  50  includes a chamber  51  of a predetermined volume carrying a piston  53  there within. The air channel  78  forms a fluid connection between the inspiratory air inlet port  81  and the top  52  of the volume chamber  51 . In this manner, when inspiratory air is drawn through the mouthpiece  91 , the piston  53  will be drawn upwardly. If a patient is drawing inspiratory air at the desired target flow rate as shown by the indicator  85 , the volume of air drawn into the patient&#39;s respiratory system can be determined by observing the calibrations  56  marked on the chamber  51 . In one manner of operation, a slidable indicator  57  is carried on the chamber  51  and may be movably positioned by the patient to a preselected volume calibration mark  56  to facilitate convenient use of the device. Outlet ports  59  are formed in the bottom portion of the chamber  51  to facilitate the piston  53  returning to the bottom of the chamber  51  when the negative pressure from the patient&#39;s inspiration of air is terminated. 
     In another manner of operation, the slidable indicator  57  is moved to its lowermost position, as illustrated in the drawings, and the GRC  60  is attached to that portion of the chamber  51  upon which the indicator  57  is carried by means of a removable mounting bracket  61  which releasably connects the GRC  60  to the chamber  51 . An indicator  62 , formed on the mounting bracket  61 , is positioned at a preselected one of the volume calibration marks  56  which corresponds to the volume of air which is desired to be drawn into the patient&#39;s lungs when using the device. A count of the number of occasions upon which a patient draws the desired volume of air into the lungs is visually displayed  63  on the GRC, and when the patient inhales a sufficient volume of air to actuate the GRC, a lamp or light emitting diode (LED)  65  is flashed for a predetermined period of time “coaching” the patient to hold the inspiration of air during the time that the LED  65  is illuminated. The manner in which the GRC  60  is actuated to record the number of occurrences in which a patient has successfully performed the desired breathing exercise, and the manner in which the LED  65  is flashed to coach the patient in the proper performance of the exercise is described in detail hereinafter with reference more particularly to FIGS. 10 and 11. 
     To adjust the time in which a desired quantity of inspiratory air has been inhaled by a patient at the desired rate of flow, a venturi plate  79  is positioned across the air channel  78  to provide an orifice of a predetermined size. In this manner, a standard sized air channel  78  can be utilized in manufacturing the device, with adjustments in the calibration of the flow rate required to be applied in order to attain the target rate, being determined by the size of the orifice  79   a  in the venturi plate  79 , and one or more tuning openings  77  which may be formed in the front wall  83 . 
     To use the same basic spirometer construction for both adult and child patient groupings, for example, a venturi plate  79  having a different sized air-flow-restricting orifice  79   a  can be utilized in the air channel  78  to accommodate different volumes of air being drawn at the desired flow rate, depending upon whether the spirometer is intended to be used by children or adults. For example an orifice  79   a  having an opening of approximately 0.1 by 0.05 inches has been found suitable for adults, while the same spirometer structure with a venturi plate  79  having an opening of approximately 0.1 by 0.07 inches has been found suitable for children. 
     As best shown in FIG. 1, the venturi plate  79  comprises two portions, one portion being attached to each of the front and back walls  83  and  84 , respectively, with a part of each portion being removed to form the orifice  79   a . For manufacturing purposes, it has been found that one of the portions forming the venturi plate  79  is best formed with the size of the part removed to form the orifice  79   a  remaining constant, while the other portion forming the venturi plate  79  may be formed with the part removed varying to change the size of the orifice  79   a  in response to the desired volume of air to be withdrawn by the user of the device. In this manner manufacturing the dimensional changes in the opening is more easily facilitated. 
     After the desired size of the orifice  79   a  has been determined, based upon the patients with whom the spirometer is to be used, the individual spirometers are then tested for correct calibration. The tuning openings or ports  77  are all initially open, and are selectively closed for any particular spirometer in order to more precisely control the rate of flow that must be inspired by the patient in order to attain the desired volumetric goals when in use. 
     In order to permit the patient to conveniently observe the instructions for use of the device, and to maintain those instructions in an accessible fashion, the base portion  30  is formed of a transparent material with an opening  31  in a skirt portion  32  of the base, best illustrated in FIG.  3 . The opening  31  is formed between the top of the base and base pads  35  upon which the device stands. In this manner documentary materials, such as the instructions  36  for the use of the device, can be inserted into the base through the opening  31 , and will be supported by the base pads  35  above the surface upon which the device is placed. Because the base is preferably formed of a transparent material, the instructions may be folded in a manner so that they are observable through the top and the bottom of the base to facilitate a patient&#39;s reference to them while the device is in use. 
     The handle portion  20  is joined at its lowermost end to the base portion  30 , and at its uppermost end to the volume chamber portion  50 . A closed portion is formed between a handle  21  and the chamber  51  enabling a patient to grasp and carry the device. An open hook projection  23  is formed by the uppermost part of the handle  21  enabling the device to be conveniently hung over a rail or a portion of a bed for convenient access by patients that are so confined. 
     Referring again to the use of the spirometer  100  with the GRC  60 , as previously disclosed, the slidable indicator  57  is moved to its lowermost position and the GRC  60  is attached to the volume chamber  51  by means of the releasable bracket  61 . The bracket  61 , formed of a resilient plastic material, has an engaging portion  61  a which slidably engages and is secured to a vertically extending post  51  a of the volume chamber  51 . The bracket  61  has an inner portion  61   b  which, along with the engaging portion  61  a, is shaped to conform to the outer cylindrical surface of the volume chamber  51  against which the back of the GRC  60  is held when the bracket  61  is attached to the chamber post  51  a. A shroud portion  6  Ic of the bracket  61  forms a  3 -sided shroud about an infra-red emitter/detector  67 , comprising an IR emitter  67   a  and an IR detector  67   b , such as a Sharp Model No. GP2S40, which is carried at the back side of the GRC  60 , to sense the presence of the piston  53  at the set position in the volume chamber  51 . In a manner hereinafter described in detail, the infra-red emitter/detector  67  will record only the movement of piston  53  within the volume chamber  51  when the spirometer  100  is sitting on its base  30 , without being falsely triggered by other occurrences. 
     As a patient withdraws inspiratory air from the volume chamber  51 , the piston  53  carried within will rise. The GRC  60  is positioned on the chamber post  51   a  with the indicator  62  formed on the bracket  61  positioned at the desired volumetric reading  56  which it is desired that the patient obtain. When the patient has withdrawn a sufficient amount of inspiratory air to raise the piston  53  to the desired level, marked by the indicator  62 , the piston  53  will reflect the infra-red signal from the emitter portion  67   a  into the detector portion  67   b  of the infra-red emitter/detector  67  whereby, upon verification of the presence of the piston  53 , the electrical circuit, illustrated in FIG. 11, will cause the display  63  to be stepped incrementally to show that the desired goal has been obtained by the patient. At the same time, the coaching lamp or LED  65  will be flashed intermittently for a predetermined time period, preferably 6 seconds, to “coach” the patient to hold their breath until the light is extinguished. In this manner the patient is informed that the desired goal has been obtained and maintained for the correct period of time. 
     Referring now to the logic block diagram or flow chart of FIG. 10, the operation of the GRC will be described in more detail. A preferred embodiment of an electrical circuit for effecting this operation is illustrated in FIG.  11 . Initially, a power source, such as a three-volt coin type battery  201 , such as a commonly available CR2032, is connected to a high-performance, four-bit microcontroller  200 , such as Model W741C250, available from Winbond Electronics Corporation America, 2727 N. 1st Street, San Jose, Calif. 95134. The power supplied to the microcontroller  200  remains on at all times until the battery  201  has been exhausted and must be replaced. When an on/reset button  64  on the GRC is depressed, power is supplied to the microprocessor  200  and also the infra-red detector circuit  67 , a liquid crystal display (LCD) array  210  through which a number appears on the display  63  of the GRC and to the light emitting diode (LED) indicator circuit  205  which includes the coaching LED  65  on the GRC. 
     When power is supplied to the GRC  60  by depressing the on/reset button  64 , the GRC will have been in either a “sleep” mode, wherein the GRC has retained the count of the previously completed exercises, or in an initial state wherein the GRC will record the number of successfully completed exercises beginning from “0”. Depression of the on/reset button  64  will actuate a keypress counter or reset shutdown timer circuit within the microprocessor  200  to energize a timing circuit so that after a time period the GRC will again be placed in a “sleep” mode in the event that the piston  53  is not elevated by a patient into the predetermined position within the time period set by this shutdown counter/timer. 
     If the on/reset button  64  is depressed for more than three seconds, the input to the LCD array  210  will display a “0” to indicate that the GRC is in condition to record a new cycle of operation beginning with the numeral “0” appearing in the window  63 . 
     If the on/reset button  64  is depressed for less than three seconds, the LCD array is energized to display in the window  63  the retained count of how many times a patient has successfully completed an exercise since the last resetting of the GRC to “0”. 
     Whether the GRC has been awakened from the “sleep” mode, wherein the previous count has been retained, or is placed in a mode to begin a new count from “0”, the microcontroller  200  places the GRC into a condition for recording the patient&#39;s next successful completion of a breathing exercise. To this end, the emitter portion  67   a  of the infrared emitter/detector  67  begins emitting a modulated I-R radiation transmission to detect the presence of the piston  53 , generating an event signal, if the piston is present in a manner hereinafter described in more detail, to eliminate any false triggering of the detector due to background noise or DC flooding of the emitter signal. 
     To prevent background noise or DC flooding from falsely triggering the infrared emitter/detector  67 , the microcomputer  200  couples a clock signal of a predetermined pulse rate to the infrared emitter/detector  67 , and compares the signal received by the detector  67   b  from the emitter  67   a , with the transmitted clock signal from the microprocessor  200  to detect the occurrence of an event signal, the presence of the piston  53 , to establish that the signal being received by the detector  67   b  is from the presence of the piston  53 , rather than the occurrence of a spurious signal such as might be caused by a person passing nearby casting a shadow across the detector  67   b  when the GRC is in one of the operational modes to receive a signal from the emitter  67   a.    
     In order to determine the occurrence of a proper event signal, the clock signal produced by the microprocessor  200  is coupled to the emitted  67   a  at a predetermined frequency, preferably 1000 Hertz. The microprocessor  200  at the same time also energizes an internal IR verification timer which is coupled to its IR detector  67   b  to establish a time “window”, preferably 50 milliseconds, for counting the number of signal pulses, IR reflections, detected within the time period defined by the timer to verify the occurrence of an event. The microprocessor IR verification timer functions to determine if a proper number of IR signals, e.g. 20, have been received by the detector  67   b  within the time period or “window” established by the microprocessor  200 . 
     If a proper event signal is received by the detector, the LED indicator circuit  205  will be energized flashing the coaching LED  65  and activating an increment counter  63  so that the patient may maintain the desired inhalation rate for a predetermined time period, preferably 6 seconds, during which the LED will remain flashing. At this time, the infrared detector  67   b  will be disabled. If the number of IR signals detected by detector  67   b  is less than its predetermined number, 20, within the time “window”, no proper event has occurred and, therefore, no proper event signal is generated. 
     At the same time as the microprocessor emits the clock signal and the IR verification timer is energized, a shutdown timer also is energized. The shut down timer will place the GRC in the sleep mode unless a proper event signal is received to reset the shutdown or sleep timer. If the shutdown timer expires, the microprocessor  200  will shut off, and the GRC will be placed in the “sleep” mode. When a proper event signal has been received, and the LED  65  flashes for the predetermined 6 sec. time period indicative of the desired time for the patient to hold their breath, the shutdown timer will be reset. If another event signal is not received before the time set for the reset shutdown timer has expired, the microprocessor  200  will shut down, and the GRC will be placed in the “sleep” mode. 
     After being placed in the “sleep” mode, if the on/reset button  64  is depressed for less than 3 seconds, the GRC will “awaken” and display the retained count of the number of exercises the patient has properly performed since the last reset of the GRC to “0” to enable a patient to continue to perform and count the number of properly performed exercises. If the on/reset button  64  is depressed for 3 seconds or longer, the GRC will be reset to “0” to begin another cycle of counting properly performed exercises. When either of these events occur, the shutdown timer will be reset, and will place the GRC in the “sleep” mode if an event signal is not received by the detector from the emitter before the shutdown timer counts out. If, however, during the time period in which the reset shutdown timer is counting a patient activates the detector by inhaling at a sufficient rate to raise the piston  53  to reflect back the IR transmission from the emitter  67   a , thereby generating an event signal, the process of recording a properly performed exercise begins and continues until such time as the therapy is completed and the GRC permitted to be placed in the “sleep ” mode. 
     While this invention has been described in the specification and illustrated in the drawings with reference to preferred embodiments, the structures of which have been disclosed herein, it will be understood by those skilled in the art to which this invention pertains that various changes may be made, and equivalents may be substituted for elements of the invention without departing from the scope of the claims. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed in the specification and shown in the drawings as the best mode presently known by the inventors for carrying out this invention, nor confined to the details set forth, but that the invention will include all embodiments, modifications and changes as may come within the scope of the following claims: