WO2005096924A1 - Procede et dispositif non invasif permettant de detecter un effort inspiratoire - Google Patents

Procede et dispositif non invasif permettant de detecter un effort inspiratoire Download PDF

Info

Publication number
WO2005096924A1
WO2005096924A1 PCT/US2005/009492 US2005009492W WO2005096924A1 WO 2005096924 A1 WO2005096924 A1 WO 2005096924A1 US 2005009492 W US2005009492 W US 2005009492W WO 2005096924 A1 WO2005096924 A1 WO 2005096924A1
Authority
WO
WIPO (PCT)
Prior art keywords
signal
emg
ekg
gain
peak
Prior art date
Application number
PCT/US2005/009492
Other languages
English (en)
Inventor
Avram R. Gold
Igor Chernyavskiy
Charles Ward
Original Assignee
The Research Foundation Of State University Of New York
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by The Research Foundation Of State University Of New York filed Critical The Research Foundation Of State University Of New York
Priority to EP05730716A priority Critical patent/EP1729636A1/fr
Priority to AU2005231133A priority patent/AU2005231133A1/en
Priority to CA002559857A priority patent/CA2559857A1/fr
Publication of WO2005096924A1 publication Critical patent/WO2005096924A1/fr

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/316—Modalities, i.e. specific diagnostic methods
    • A61B5/389—Electromyography [EMG]
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/316—Modalities, i.e. specific diagnostic methods
    • A61B5/318—Heart-related electrical modalities, e.g. electrocardiography [ECG]
    • A61B5/346—Analysis of electrocardiograms
    • A61B5/349—Detecting specific parameters of the electrocardiograph cycle

Definitions

  • the invention relates generally to the diagnosis and treatment of breathing disorders in sleeping and waking subjects.
  • the invention relates to an electrical device for monitoring and processing an electromyogram (EMG) signal.
  • EMG electromyogram
  • the electrical device comprises non-invasive skin surface electrodes for the detection of EMG signals.
  • the electrical device comprises a system for monitoring and recording of data by a patient such that a breathing disorder may be diagnosed by a clinician.
  • UARS upper airway resistance syndrome
  • the invention relates generally to the diagnosis and treatment of breathing disorders in sleeping and waking subjects.
  • the invention relates to an electrical device for monitoring and processing an electromyogram (EMG) signal.
  • EMG electromyogram
  • the electrical device comprises non-invasive skin surface electrodes for the detection of EMG signals.
  • the electrical device comprises a system for monitoring and recording of data by a patient such that a breathing disorder may be diagnosed by a clinician.
  • One embodiment of the present invention contemplates a method, comprising: a) detecting an electrocardiogram signal within an electromyogram signal, said electrocardiogram signal comprising a QRS complex, said QRS complex having an amplitude; b) calculating an averaged amplitude of the QRS complex within said electrocardiogram signal; c) comparing said averaged amplitude with a trigger value and generating a blanking pulse wherein said averaged amplitude exceeds said trigger value, said blanking pulse causing a blanker device to remove said electrocardiogram signal from said electromyogram signal.
  • said electromyogram signal is generated from skin surface electrodes connected to a subject.
  • said calculating of step (b) is performed by a microcontroller connected to said electrodes.
  • One embodiment of the present invention contemplates a system, comprising: a) a plurality of skin surface electrodes connected to a subject under conditions such that a electromyogram signal is generated, said electromyogram signal comprising a contaminating electrocardiogram signal, said electrocardiogram signal comprising a QRS complex, said QRS complex having an amplitude; b) a microcontroller connected to said electrodes, said microcontroller capable of i) calculating an averaged amplitude of the QRS complex within said electrocardiogram signal, ii) comparing said averaged amplitude with a trigger value, and iii) generating a blanking pulse wherein said averaged amplitude exceeds said trigger value; and c) an EKG blanker configured to receive said blanking pulse, said EKG blanker capable of i) receiving said electromyogram signal comprising said electrocardiogram signal, and ii) removing said electrocardiogram signal from said electromyogram signal.
  • One embodiment of the present invention contemplates a system, comprising: a) a plurality of skin surface electrodes connected to a subject under conditions such that a contaminated electromyogram signal is generated, said contaminated electromyogram signal comprising a contaminating electrocardiogram signal, said electrocardiogram signal comprising a QRS complex, said QRS complex having an amplitude; b) first and second parallel filters configured for receiving said contaminated electromyogram signal; c) a microcontroller connected to said first filter so as to receive a filtered electrocardiogram signal, said microcontroller capable of i) calculating an averaged amplitude of the QRS complex within said filtered electrocardiogram signal, ii) comparing said averaged amplitude with a trigger value, and iii) generating a blanking pulse wherein said averaged amplitude exceeds said trigger value; and d) an EKG blanker connected to said second filter so as to receive a filtered electromyogram signal, said EKG blanker further configured to receive said blanking pulse, said E
  • One embodiment of the present invention contemplates a method for diagnosing a breathing disorder, comprising: a) providing; i) a subject suspected of having a breathing disorder; ii) a plurality of skin surface electrodes capable of contacting said subject, wherein said electrodes are configured to generate a composite electromyogram signal, wherein said composite electromyogram signal comprises an electrocardiogram artifact signal; iii) a microcontroller connected to said electrodes and configured to trigger a blanking pulse upon calculation of a threshold average QRS peak from within said electrocardiogram artifact signal; and iv) an EKG blanker configured to receive said blanking pulse, wherein said blanker device is reconfigured to receive a moving average electromyogram signal; b) calculating said average QRS value from said electrocardiogram artifact signal by said microcontroller, wherein said threshold average QRS value is detected; c) triggering said blanking pulse by said microcontroller upon detection of said threshold average QRS value; d) reconfiguring said EKG blanker by said blanking
  • the method further comprises the step of contacting said patient with said surface electrodes. In one embodiment, the method further comprises the step of filtering said electrocardiogram artifact signal into a channel to create an exaggerated electrocardiogram artifact signal. In one embodiment, the method further comprises the step of delaying said composite electromyogram signal. In one embodiment, said composite electromyogram signal comprises a diaphragmatic electromyogram signal. In one embodiment, said reconfiguring of said EKG blanker replaces said electrocardiogram artifact signal with said moving average electromyogram signal. In one embodiment, at least one of said surface electrodes is contacted with said patient at the anterior axillary line. In another embodiment, at least one of said surface electrodes is contacted with said patient at the mid-axillary line.
  • an EMG monitoring device for diagnosing a breathing order, comprising: a) an isolation amplifier comprising an input lead and an output lead, wherein said isolation amplifier input lead is connected to a plurality of skin surface electrodes; b) a first channel comprising a band-pass filter and an EKG gain amplifier, wherein said first channel is connected to said isolation amplifier output lead; c) a second channel comprising a high-pass band filter and a composite EMG gain amplifier wherein said second channel is connected to said isolation amplifier output lead; d) a first microcontroller comprising an EKG input lead and an EKG output lead connected to said EKG gain amplifier, an EMG input lead and an EMG output lead connected to said EMG gain amplifier and a blanking pulse output lead; e) a second microcontroller comprising an input lead and an output lead wherein said second microcontroller input lead is connected to said EMG gain amplifier output lead; f) an EKG blanker comprising an analog switch, a composite EMG input lead connected to said second
  • said second microcontroller further comprises a digital delay circuit.
  • the device further comprises a monitor connected to said output lead of said moving averager.
  • a system for diagnosing a breathing disorder comprising: a) a subject suspected of having a breathing disorder wherein said subject is contacted with a plurality of skin surface electrodes; b) a diagnostic device capable of activation by said subject and connected to said electrodes, wherein said diagnostic device comprises; i) an isolation amplifier capable of receiving a composite electromyogram signal from said electrodes; ii) a first channel capable of exaggerating an EKG artifact signal within said composite electromyogram signal; iii) a first microcontroller capable of triggering a blanking pulse upon detection of a threshold average QRS complex within said EKG artifact signal; iv) an EKG blanker comprising an analog switch, wherein said analog switch is reconfigured from receiving said composite EMG signal to receiving a moving averager output signal upon detecting said blanking
  • said surface electrodes are contacted with said patient by trained personnel.
  • said data recorder is further capable of storing said clean electromyogram signal, said electrocardiogram artifact signal and said composite electromyogram signal.
  • the system further comprises a computer reversibly connected to said data recorder, wherein said stored signals are downloaded for processing.
  • sleep disorder refers to any condition that disrupts a patient's ability to progress through the normal phases of sleep, as accepted in the art.
  • a sleep disorder may prevent a patient from reaching Stage IN (i.e., for example, rapid-eye- movement (REM)) wherein a patient engages in dreaming (the most restful stage of sleep) when caused by either obstructive sleep apnea or centrally-mediated sleep apnea.
  • Stage IN i.e., for example, rapid-eye- movement (REM)
  • REM rapid-eye- movement
  • a sleep disorder including, but not limited to, obstructive sleep apnea or upper airway resistance syndrome may modify the normally sinusoidal breathing pattern, such that paradoxical diaphragm and geniglossal muscle movement occur.
  • a sleep disorder based upon a centrally-mediated sleep apnea may simply be expressed as a cessation of breathing.
  • Other types of non-respiratory sleep disorders are contemplated by the present invention including, but not limited to, problems with staying and falling asleep, problems with staying awake, problems with adhering to a regular sleep schedule and sleep-disruptive behaviors.
  • the term "symptoms of a sleep disorder", as used herein,' refers to clinical manifestations consistent with a disruption of the normal phases of sleep.
  • Symptoms include, but are not limited to, altered ventilation states, restless leg movements, bruxing, daytime fatigue, excessive daytime sleepiness, irritability, high blood pressure, low blood oxygen content, cardiac ischemia, stroke, awakening in the night, difficulty falling asleep, loud snoring, episodes of stopped breathing, sleep attacks during the day, depressed mood, anxiety, difficulty concentrating, apathy or loss of memory.
  • the symptom expressed as an altered ventilation state comprises a paradoxical breathing pattern wherein the diaphragm contraction and geniglossal contraction are not properly synchronized.
  • patient refers to any living mammal, human or non- human.
  • EKG blanker refers to any electronic device having the capability to selectively remove any contaminating waveform that reduces the sensitivity and precision of an electromyogram (EMG).
  • a contaminating waveform may comprise an electrocardiogram (EKG) artifact signal.
  • EKG blanker device does not generate "flat spots” in a cleaned EMG that results in data loss in most currently used methods to remove EKG artifact.
  • flat spots refers to regions on a "clean EMG” that are at or near baseline (i.e., no activity) following a non-selective removal of a contaminating waveform.
  • clean EMG refers to an EMG signal from which contaminating waveforms have been removed (i.e., for example, by replacement with a moving average signal).
  • a clean EMG includes, but is not limited to, output from an EKG blanker to a moving averager as contemplated by the present invention.
  • electrocardiography refers to a test that generates an electric signal (i.e., an EKG signal) produced by the sequential depolarization of the heart chambers.
  • QRS complex refers to a portion of an EKG representing the actual successive atrial/ventricular contraction of the heart.
  • averaged QRS refers to an arithmetic average of the area-under-the-curve (i.e., integral) of the QRS portion of an EKG signal.
  • the calculation of averaged QRS may be performed using peak detection (i.e, for example, by using a software algorithm).
  • a peak detection algorithm may be based on a simple first difference approach by examining the variation between maximum QRS complex amplitude and baseline EKG signal amplitude (i.e., for example, occuring immediately prior the QRS complex).
  • the threshold used by the peak detection logic i.e., resulting the detection of a "threshold average QRS complex" is intially established during a patient initialization (i.e., for example, during electrode stabilization) process.
  • the threshold is a preset value (i.e, for example, a trigger value) wherein the present value is between approximately 50 - 90 % of the average QRS complex, preferably between 60 - 80 % of the average QRS complex and more preferably between .
  • the threshold is not a fixed quantity and dynamic, thereby changing during the recording procedure.
  • the threshold is determined from the overall amplitude of a pateint's typical QRS complex. This is done to allow for the variation in the QRS amplitude with respect to respiration, body posture etc. This is accomplished by computing the running average of QRS amplitudes and using the average amplitude to determine the threshold.
  • the present invention uses two different thresholds to detect QRS complexes. During the first pass over the data, a high threshold is used to detect only normal QRS complex amplitudes. Small QRS complex amplitudes, however, may be missed but are recoverable by using a subsequent low threshold detection pass.
  • One embodiment contemplates a QRS identification algorithm that identifies a lack of a QRS signal in a region of an EKG signal where a QRS signal is expected such that the low threshold detection pass is implemented.
  • electromyography refers to a test that generates an electric signal (i.e., an EMG signal) produced by the depolarization of muscle tissue.
  • an electromyogram will be detected by a set of skin surface electrodes resulting from any and all muscle depolarizations and thus may comprise an electrical signal or a visual representation of an electrical signal.
  • a surface EMG signal is detected by an empirical determination of the proper manner of placement and location of skin surface electrodes that minimizes the detection of inspiratory muscle electromyograms other than a diaphragmatic EMG (EMGdi).
  • One empirically derived electrode placement contemplated by the present invention comprises skin surface electrodes placed at the seventh and eighth intercostal space along the axillary and mid-axillary chest lines, respectively.
  • composite refers to a multiple waveform comprising at least two individual waveforms. Individual waveforms include, but are not limited to, electromyogram signals and electrocardiogram signals.
  • exaggerated refers to a composite waveform wherein one waveform predominates. The present invention contemplates the exaggeration of at least one waveform in relation to a composite waveform by using a combination of band pass filters.
  • the exaggeration process comprises a specific sequence of low-pass band filters and high-pass band filters (i.e., operating between approximately 14 - 4000 hertz and -12 dB/octave). Exaggerated waveforms may be independently manipulated to improve the gain and amplitude in preparation for triggering a blanking pulse.
  • surface electrode refers to any electrically conductive component, that when properly placed on the outside epidermal layer (i.e, skin) of a patient, detects physiological electrical activity (i.e, for example, an EMG).
  • physiological electrical activity i.e, for example, an EMG
  • microcontroller refers to any electronic device capable of receiving, processing and transmitting analog or digital signals (i.e., for example, a printed integrated circuit). For example, a microcontroller may be configured to use software programs to perform arithmetic calculations. Alternatively, a microcontroller may be configured to use software programs to route electronic signals to specific destinations.
  • input refers to any electrical signal that is received by an electrical component for reconfiguration and/or processing.
  • output refers to any electrical signal that is transmitted by an electrical component after reconfiguration and/or processing.
  • channel refers to any electrical pathway used to transmit an electrical signal within or between electronic devices.
  • a channel may include, but is not limited to, microchips comprising etched or photoresist electrically conductive pathways, shielded cables or metal alloy wires.
  • the term "connected”, as used herein, refers to any electrical circuit configured to transmit a signal from one component to another component. It is not intended to limit the configuration to adjacent components. The present invention specifically contemplates that non-adjacent components (i.e., those physically separated by intervening components) may be connected.
  • the term “reconfiguring” or “reconfigured”, as used herein, refers to any change in the routed pathway of an electrical signal within an electronic device. For example, reconfiguring may include, but is not limited to, an analog switch or a digital component (i.e., for example, a microchip).
  • delay refers to a transient interruption in a signal transmission through a microcontroller (i.e., for example, by use of a digital delay circuit). For example, a delay comprises approximately 50 milliseconds (msec).
  • transmission or “transmitting”, as used herein, refers to the movement of an electrical signal from one component to another component of an electrical circuit
  • moving averager refers to an electronic component that is capable of computing (i.e., for example, by being configured with an algorithm) iterative averages over specific time intervals of a continuous waveform based on the frequency and amplitude (i.e., for example, an EMGdi waveform).
  • displaying refers to any visual physical representation of an electrical signal (i.e., for example, an EKG or EMG).
  • physical representations may include, but are not limited to, digital monitors, liquid crystal displays, light emitting diode displays, strip chart recorders or computer hardcopy printouts.
  • intercostals refers to any area between two ribs.
  • the seventh intercostal space comprises the area between the seventh and eight rib and the eighth intercostal space comprises the area between the eighth and ninth ribs (on either the left or right side of a patient's body).
  • anterior axillary line refers to an imaginary straight vertical line continuing the line of the anterior axillary fold with the upper limb in the anatomical position.
  • mid-axillary line refers to an imaginary straight vertical line halfway between the anterior axillary line and the posterior axillary line, passing through the apex of the axilla.
  • EMG monitor refers to any electronic device that is capable of calculating a maEMGdi without EKG artifact signals by detecting a composite EMG with surface electrodes.
  • diagnostic device refers to an electronic device that may be operated by a patient and capable of monitoring, detecting and storing physiological data that enables a skilled clinician to diagnose a breathing disorder (i.e, for example, sleep apnea or upper airway resistance syndrome).
  • a diagnostic device i.e., for example, an EMG monitor
  • positive pressure ventilation device refers to the administration of a gas (i.e, for example, room air) to the lungs of a patient exhibiting at least one symptom of a breathing disorder (i.e., for example, a commercially available continuous positive airway pressure device; CPAP)).
  • Figure 1 illustrates an exemplary relationship between moving average diaphragmatic EMG ( ⁇ maEMGdi) measured with an esophageal electrode and esophageal pressure ( ⁇ Pes) during a hypercapnic challenge.
  • V inspiratory flow
  • P ga gastric pressure
  • Pdi transdiaphragmatic pressure.
  • Figure 2 demonstrates one embodiment of the relationship between maEMGdi and Pes.
  • Figure 3 shows an exemplary data tracing of an EMG signal that contains and EKG artifact signal. Top trace: rectified composite EMG. Bottom trace: moving average signal showing residual EKG artifact contamination.
  • Figure 4 shows an exemplary data tracing of an individual EKG artifact signal.
  • Figure 5 illustrates one example of surface electrode positioning for measuring ⁇ maEMGdi as contemplated in one embodiment of the present invention.
  • the anterior axillary line is defined by the lateral margin of the pectoralis (upper arrowheads) while the posterior axillary line is defined by the lateral border of the latissimus dorsi (lower arrowheads).
  • electrodes are shown placed in the lowest interspace intersecting the anterior axillary line and the next lower interspace in the mid-axillary line.
  • Figure 6 shows one embodiment of an EMG monitor.
  • Figure 7 illustrates one embodiment of an electronic schematic of an EMG monitor.
  • Figure 8 demonstrates one example of a polygraph recording of a subject breathing at increasing levels of nasal obstruction.
  • FIG. 9 illustrates exemplary correlations between ⁇ maEMGdi and ⁇ Pes for eight subjects.
  • Figure 9 A presents data for Subjects 1 - 4 and
  • Figure 9B presents data for Subjects 5 - 8.
  • Y-Axis ⁇ maEMGdi (millivolts).
  • X-Axis ⁇ Pes (cm H 2 0)
  • Figure 10 demonstrates one possible relationship between ⁇ maEMGdi and ⁇ Pes as 1 a function of body position as demonstrated in Subjects 3, 7 and 8.
  • Y-Axis ⁇ maEMGdi (millivolts).
  • X-Axis ⁇ Pes (cm H 2 0). Supine - ⁇ data point with a solid regression line; Right Side - o data point with a dashed regression line; Left Side - x data point with a dotted regression line.
  • Figures 11 A and 1 IB demonstrate one possible relationship between maEMGdi and Pes from four sleep disordered asleep subjects (A-D) undergoing positive pressure ventilation with a CPAP device.
  • Y-Axis ⁇ maEMGdi (millivolts).
  • X-Axis ⁇ Pes (cm H 2 0). o data point with a solid regression line.
  • Figure 12 presents representative data showing a diagnosis of upper respiratory airway syndrome (UARS).
  • This invention relates generally to the treatment of breathing disorders in sleeping and waking subjects.
  • the invention relates to an electrical device for monitoring and processing an electromyogram (EMG) signal.
  • the electrical device comprises non-invasive skin surface electrodes for the detection of EMG signals.
  • the electrical device comprises a system for monitoring and recording of data by a patient such that a sleep disorder may be diagnosed by a clinician.
  • This invention relates generally to the treatment of breathing disorders in sleeping and waking subjects. More particularly, the invention relates to the treatment of disorders emanating from upper airway obstruction and to methods and devices for detecting, evaluating, monitoring and ameliorating the adverse effects of such obstructions.
  • the invention relates to an electrical device (i.e., for example, an EMG monitor) for monitoring and processing a composite electromyogram (EMG) signal.
  • the electrical device comprises non-invasive skin surface electrodes.
  • One advantage of the device comprises an automatic replacement of an electrocardiogram (EKG) artifact signal (i.e., deemed as artifact in regards to the present invention) that one skilled in the art would consider rendering a composite EMG signal useless for quantitative analysis.
  • EKG electrocardiogram
  • Another advantage of the device is that it is useful for sleep studies or other applications where it is desirable to measure human diaphragm muscle activity.
  • Another advantage of the device is that may be operated by a patient.
  • thermocouples to measure inspiratory airflow and circumferential movement sensors to detect chest and abdominal movement to measure inspiratory effort.
  • thermocouples to measure inspiratory airflow and circumferential movement sensors to detect chest and abdominal movement to measure inspiratory effort.
  • thermocouples and movement sensors that are adequate for the diagnosis of OSA/H patients, however, fail to distinguish UARS patients from normals, because inspiratory airflow and effort are only slightly decreased in UARS patients.
  • the physiologic correlates of UARS include, but are not limited to, an inspiratory airflow plateau (demonstrable by pneumotachygraph) and an increased inspiratory effort (demonstrable by esophageal manometry).
  • Gold et al "Upper Airway Collapsibility During Sleep In Upper Airway Resistance Syndrome” Chest 121:1531-1540 (2002); and Guilleminault et al, "A Cause Of Excessive Daytime Sleepiness. The Upper Airway Resistance Syndrome" Chest 104(3):781-7 (1993).
  • One technological innovation has enabled effective UARS diagnosis by identifying mild levels of inspiratory airflow limitation during sleep that includes the use of a nasal cannula to make nasal/oral pressure measurements.
  • the measurements obtained from the cannula adequately demonstrate the plateau characteristic of a mild inspiratory airflow limitation.
  • Hosselet et al "Detection Of Flow Limitation With A Nasal CannulaPressure Transducer System” Am JRespir Crit Care Med 157(5 pt 1): 1461 -1467 (1998).
  • a disadvantage of this less invasive approach is that the sensitivity of inspiration effort measurements is not comparable to esophageal manometry.
  • a reliable surrogate for esophageal manometry is needed to improve the quality of diagnosis for mild breathing disorders.
  • the present invention contemplates the diagnosis of UARS by a method comprising the detection of EMGdi in a patient.
  • the patient may be placed on a therapy comprising a positive pressure ventilation device.
  • a positive pressure ventilation device comprising a positive pressure ventilation device.
  • Sackner et al teaches that the Graseby capsules measures abdominal wall movement rather than an overall abdominal or rib cage respiratory signal.
  • a significant improvement in the measurement of diaphragmatic EMG involved the use of surface electrodes. Skin surface EMGdi was detected with intercostal electrodes (placed in the 6th and 7th interspaces anteriorly) in quadriplegic patients having nerve lesions above the first thoracic vertebra (i.e., the intercostal muscles were paralyzed).
  • Gross et al "The Effect Of Training On Strength And Endurance Of The Diaphragm In Quadriplegia" Am J. Med 68:27-35 (1980).
  • Kumar et al "Analysis Of Sleep Apnea” United States Patent Application 2003/0139691, Filed: January 22, 2003. Published: July 24, 2003.
  • the mechanical aspects of thoracic and abdominal effort is detected by piezo/PDF belts or inductance/impedance measurements.
  • the signals are evaluated for separation of a calculated phase angle allowing either a diagnosis for sleep apnea or indicating a necessity for CPAP pressure adjustments.
  • This approach did not detect or disclose any relationship between EMGdi and Pes. Relative relationships between EMGdi and Pes were discussed in regards to a method and device that generates a signal to adjust ventilatory support units.
  • Sinderly et al "Method And Device Responsive To Myoelectrical Activity For Triggering Ventilatory Support", United States Patent No. 6,588,423, Filed: June 22, 2001. Issued: July 8, 2003.
  • Sinderly et al teaches that EMGdi is preferably measured by using an esophageal catheter which contains an number of electrodes. This catheter is intranasally passed and enters the diaphragm muscle in order to detect depolarization signals.
  • Diaphragm EMG is an indirect measurement of respiratory effort.
  • One embodiment of the present invention contemplates that the magnitude of a surface diaphragmatic moving average EMG change ( ⁇ maEMGdi) is positively correlated in relation to the magnitude of an inspiratory esophageal pressure change
  • ⁇ Pes in waking subjects with upper airway obstruction (i.e., for example, upon resistive loading of the nasal airway).
  • One embodiment contemplates a method of measuring a correlation between ⁇ maEMGdi and ⁇ Pes comprising: surface electrodes, placed intercostally (i.e., for example, within the seventh and eight interspaces), under conditions that detect diaphragmatic EMG from subjects with increased upper airway resistance that has a positive correlation with inspiratory effort measured by esophageal manometry.
  • the correlation is present at varying levels of obesity.
  • the correlation is present in recumbent individuals irrespective of whether the individual's body position is supine or recumbent on the left or right sides.
  • One embodiment of the present invention contemplates a method to reduce progressively increasing inspiratory effort during sleep apnea (i.e., for example, obstructive or central), upper airway resistive syndrome or other inspiratory flow limitation.
  • a progressive decrease in the magnitude and variability of inspiratory effort occurs by increasing pressure from a positive pressure ventilation device (i.e.
  • FIG. 2 For example, a nasal continuous positive airway pressure device; CPAP) to therapeutic levels.
  • therapeutic CPAP administration decreases a ⁇ maEMGdi value.
  • Figure 2 Another embodiment of the present invention contemplates a method to remove (i.e., for example, replace by blanking) electrical impulses from the heart (i.e., for example, EKG artifact signals) out of the surface EMGdi signal. It is known in the art of polysomnography that surface electrode EMG signals are contaminated by electrocardiogram (EKG) artifact signals.
  • the present invention contemplates a method of diagnosis and treatment of a patient exhibiting at least one symptom of a subtle respiratory disturbance (i.e., for example, a breathing disorder).
  • the disturbance comprises UARS.
  • the invention contemplates a degree of sensitivity, accuracy, reliability and automatic operability not currently available in the art.
  • the present invention is capable of performing diagnosis and changes in treatment parameters to patients either on an outpatient basis or at home.
  • one embodiment contemplates a diagnostic device (i.e., for example, an EMG monitor) comprising surface electrodes integrated into an electronic circuit.
  • the device comprises a setup software function that is capable of automatically adjusting gain to standardize the amplitude of composite EMG and EKG artifact signals.
  • the composite EMG signal comprises a diaphragmatic EMG (EMGdi) signal.
  • the diagnostic device After an appropriate stabilization period (i.e., for example, between 15 — 20 minutes), the diagnostic device would automatically begin recording data. It is further believed that this stabilization period accommodates a physiological adaptation of the skin cells to the presence of the active electrodes (i.e., for example, stabilization of cell membrane ion channels).
  • an associated recording device i.e., for example, a digital memory microchip
  • This diagnostic device is operated by the patient and is contemplated to provide data for the diagnosis of breathing disorders.
  • a diagnostic device operated by the patient is contemplated as a system comprising a positive pressure ventilation device such that a diagnostic device provides real-time adjustments in the delivered air pressure by the positive pressure ventilation device.
  • Another advantage of the present invention contemplates a method comprising: providing a subject and an EMG monitor having an electronic circuit (i.e., for example, an EKG blanker) capable of replacing an EKG artifact signal within a patient's composite EMG signal.
  • an EKG blanker capable of replacing an EKG artifact signal within a patient's composite EMG signal.
  • a patient's EKG artifact signal is detected by a threshold amplitude of an average QRS complex.
  • an electronic circuit replaces the detected EKG artifact signal within a delayed composite EMG signal (i.e., for example, a delay of approximately 50 milliseconds) with moving averager output data.
  • the present invention contemplates an EMG monitor comprising a highly sensitive and precise maEMGdi signal.
  • an EMG monitor comprises a channel having a composite electromyogram signal (i.e., for example, by filtering waveforms having a frequency of approximately between 50 - 3,000 Hz).
  • an EMG monitor comprises a channel having an exaggerated electrocardiogram signal (i.e., for example, by filtering waveforms having a frequency of approximately between 1 - 50 Hz).
  • an exaggerated electrocardiogram signal identifies 100% of EKG artifact signals within a composite EMG signal.
  • optimization of an individual EKG signal allows calculation of an average QRS amplitude having a predetermined threshold (i.e, for example, when 75% of any detected QRS complex meets or exceeds a 1.5 volt peak-to-peak average).
  • detection of a threshold average QRS complex triggers a blanking pulse that reconfigures an analog switch within an EKG blanker to receive moving averager output as an incoming signal.
  • this moving averager output "replaces" (i.e., blanks out) the EKG artifact signal within the incoming delayed composite EMG signal.
  • contamination of EMGdi signals with EKG artifact signals is a known problem in the art.
  • Another embodiment of the present invention replaces EKG artifact signal from composite EMGdi signals on a real-time basis.
  • Prior efforts have been limited to iterative processes that matches (by linear regression) existing EKG templates (residing in a database) with the contaminating EKG artifact signal found within the recording of an expiratory EMGdi signal. This process requires approximately twelve hours of comparison effort to process and clean 30 minutes of EMGdi signal.
  • the prototype Model SB-1 subtracted the EKG artifact signal from the EMG signal by: i) merely nulling-out the EMG signal during the blanking interval thereby creating nonsense "flat spots" or ii) substituting a portion of the undelayed EMG signal for the blanked signal.
  • prototype Model SB-1 was subject to interference from the inevitable switching transients and discontinuities produced when cutting and pasting high-frequency EMG signals.
  • the prototype Model SB-1 utilized highly complicated circuitry in the microcontroller for gain adjustment and EMG signal delays.
  • Certain embodiments of the present invention comprise printed integrated circuit microcontrollers comprising simplified circuitry configured with algorithms (i.e., software programs) that: i) automatically adjust EKG artifact signal gain and composite EMG signal gain independently; ii) digitally delay the composite EMG signal and iii) calculate an maEMGdi from a clean EMG signal.
  • algorithms i.e., software programs
  • i) automatically adjust EKG artifact signal gain and composite EMG signal gain independently ii) digitally delay the composite EMG signal and iii) calculate an maEMGdi from a clean EMG signal.
  • an EKG artifact signal is detected by a microprocessor (i.e., for example, by calculating a threshold average QRS complex)
  • the EKG blanker may be reconfigured (i.e., for example, by an analog switch) to receive moving average EMG output signals at the same time the delayed composite EMG signal is received by the EKG blanker.
  • Initial attempts to optimize this blanking process were unsuccessful.
  • the EKG artifact signal usually having a greater amplitude than the composite EMG signal, is sometimes reduced in size such that a ready discrimination between the EMG signal component and EKG artifact signal component by amplitude is not possible (See Figure 3). This situation causes erratic EKG-mediated triggering of blanking pulses and consequently poor EMG blanking performance.
  • a composite EMG signal channel comprises two band-pass filters, a programmable gain amplifier configured to interact with a microcontroller configured with a gain-adjusting algorithm to perform automatic gain adjustment.
  • an individual EKG signal path comprises one band-pass filter, a programmable gain amplifier configured to interact with a microcontroller configured with a gain-adjusting algorithm to perform automatic gain adjustment.
  • a microcontroller configured with a gain-adjusting algorithm interacts with an EKG artifact signal channel programmable gain amplifier and a composite EMG signal channel programmable gain amplifier, wherein the amplitude of the EKG artifact signal and the amplitude of the composite EMG signal are independently adjusted.
  • Figure 4 shows a tracing from a representative exaggerated EKG artifact signal subsequent to filtering into an individual channel and optimal gain adjustment.
  • the present invention also solves a problem known in the art regarding the validity of the surface diaphragmatic EMG due to contamination with EMG activity from other inspiratory muscles of the chest wall.
  • the present invention contemplates a method of measuring EMGdi comprising placing a plurality of surface electrodes at the seventh and eighth interspaces on the anterior axillary line and mid-axillary line, respectively.
  • the chest wall inspiratory muscles having the greatest potential to interfere with EMGdi are the parasternal internal intercostal muscles and the external intercostal muscles of the most rostral interspaces.
  • De Troyer A. "The Respiratory Muscles", In: The Lung: Scientific Foundations, pp. 1203-1215, 2nd Ed., Eds. Crystal et al, Lippincott - Raven, Philadelphia - New York (1997). It is also believed, therefore, that placement of the electrodes at the seventh and eighth interspaces is unlikely to detect contaminating EMG signals generated by the parasternal (internal or external) intercostal chest wall inspiratory muscles.
  • the present invention contemplates a method for detecting diaphragmatic electromyograms using a plurality of skin surface electrodes.
  • at least one electrode is placed along the anterior axillary line of the chest.
  • at least one electrode is placed along the mid-axillary line of the chest.
  • One advantage of the present invention contemplates an electrode placed in the seventh intercostal space.
  • Another advantage of the present invention contemplates an electrode placed in the eighth intercostal space.
  • An empirically derived method of electrode placement comprising a specific manner and location is necessary because the contribution of intercostal inspiratory muscles to esophageal pressure may vary between NREM and REM sleep.
  • an electrode location overlies an area of opposition between the diaphragm and the chest wall and minimizes the length of the conduction path between the diaphragm muscle and the electrodes. See Figure 5- showing that the diaphragm is sandwiched between the liver and the ribcage.
  • the invention is not limited, however, by the site at which the electrodes are secured to the chest wall.
  • inventions that comprise (as a non-limiting example) the placement of additional electrodes to acquire EMG signals from active non-diaphragm inspiratory muscles for use in decontaminating the diaphragmatic EMG signal by appropriate signal processing. It is also conceivable to use design-shaped surface electrodes that preferentially acquire diaphragmatic EMG signals. As described above, the present invention contemplates a device for detecting diaphragmatic EMG activity comprising an EMG monitor. It is not intended to limit the present invention by the following description of an EMG monitor device because one having skill in the art will recognize that many alternative designs are possible to facilitate similar signal processing.
  • the EMG monitor described below is intended only as an example and comprises the following functional parts: i) an isolation amplifier for safely amplifying the signal received from skin electrodes; ii) a variable gain amplifier adjusted by a microcontroller configured with an algorithm; iii) a digital EKG blanker to replace the EKG artifact signal within the composite EMG signal and, iv) a moving averager for creating an envelope around the EMG activity.
  • an isolation amplifier for safely amplifying the signal received from skin electrodes
  • a variable gain amplifier adjusted by a microcontroller configured with an algorithm
  • a digital EKG blanker to replace the EKG artifact signal within the composite EMG signal
  • iv) a moving averager for creating an envelope around the EMG activity.
  • the monitor comprises a medical grade isolation amplifier with direct electrode connections, a moving averager and a novel EKG artifact signal suppression function (i.e., for example, an EKG blanker connected to a digital delay circuit).
  • a medical grade isolation amplifier with direct electrode connections, a moving averager and a novel EKG artifact signal suppression function (i.e., for example, an EKG blanker connected to a digital delay circuit).
  • the EMG monitor operates within the following parameters: i) an isolation voltage of either approximately 1500 volts continuous or approximately 2000 volts @ approximately 10 second pulse intervals; ii) a leakage current of approximately 10 microamperes when receiving any input; iii) wideband noise (referred to input) of approximately ⁇ 7 microvolts peak-to-peak and approximately ⁇ 3 microvolts root-mean- square and iv) a common mode rejection of approximately > 100 dB @ approximately 60 hertz.
  • an EMG monitor contemplated by the present invention has several advantages over prior attempts in the art to replace EKG artifact signals within composite EMG signals: i) a setup mode where the gain of the isolation amplifier is automatically adjusted to produce standardized signal levels; ii) a liquid crystal display (LCD) window showing current settings and operator messages; iii) an integrated measurement of heart rate and respiratory rate; and iv) a digital delay circuit that delays the composite EMG signal (i.e., for example, by approximately 50 milliseconds) which allows a microcontroller to predict when a contaminating EKG artifact signal will be received by an EKG blanker thus allowing an effective replacement of the EKG artifact signal by a moving averager output signal.
  • a setup mode where the gain of the isolation amplifier is automatically adjusted to produce standardized signal levels
  • LCD liquid crystal display
  • iii) an integrated measurement of heart rate and respiratory rate iii)
  • a digital delay circuit that delays the composite EMG signal (i.e., for example, by
  • the EMG monitor comprises the dimensions of approximately 10 x 3.5 x 8 inches (i.e., width-height-depth) and a weight of approximately three pounds. See Figure 6.
  • the composite EMG signal delay is between approximately 30 - 80 milliseconds, preferably between approximately 40 - 70 milliseconds and more preferably between approximately 45 - 55 milliseconds.
  • Output signals from an EMG monitor 100 include, but are not limited to, AMP OUT 105 (a raw, amplified composite EMG signal having a range of approximately ⁇ 2 volts @ approximately 10 milliamperes); GATED EMG OUT 110 (a full- wave rectified clean EMG signal having a range between approximately 0 - 2 volts @ approximately 10 milliamperes, with nulls (i.e., for example, "flat spots") inserted where the EKG artifact blanking occurs by reconfiguration of analog switch 15); GATE PULSE 115 (an approximate 5 volt logic pulse that is TTL compatible coinciding with the blanking pulse interval that is synchronous with a detected EKG artifact signal); and M.A.
  • AMP OUT 105 a raw, amplified composite EMG signal having a range of approximately ⁇ 2 volts @ approximately 10 milliamperes
  • GATED EMG OUT 110 a full- wave rectified clean EMG signal having a range between approximately 0 -
  • OUT 120 (the moving average output signal having a range of approximately 0 - 2 volts @ approximately 10 milliamperes).
  • EMG monitor When the EMG monitor is first switched ON using the rear panel power switch (not shown), a sign-on message is shown with an LCD window 130. After a few seconds, the EMG monitor will begin operating.
  • Another embodiment of the present invention contemplates a method for performing an EMG monitor operational routine comprising: a) connecting the input cable leads to the EMG monitor; b) stabilizing the electrode signals, wherein said stabilization time period is at least fifteen minutes; c) performing a method comprising a setup routine, wherein said routine optimizes the EKG artifact signal gain.
  • EKG artifact signal gain is automatically optimized by selecting the SETUP SWITCH 135 to AUTO on an EMG monitor front panel.
  • the peak amplitudes of the EKG artifact signals are monitored during approximate 3.5 second epochs, wherein the gain is iteratively adjusted to increase or decrease the amplitude to provide an optimized EKG artifact signal.
  • an LCD window 130 shows the current EKG artifact signal status including, but not limited to: [HI] - indicating that the signal amplitude is too large for processing; [LO] - indicating that the signal amplitude is too small for processing or [OK] - indicating that the signal amplitude is within the target range for processing.
  • the EKG artifact signal amplitude is within target range for processing when the PWR/AUX light 140 is flashing rapidly.
  • the EKG artifact signal gain is manually optimized by selecting SETUP SWITCH 135 to MANUAL on the EMG monitor front panel and adjusting the gain setting by turning the ADJUST knob 145.
  • optimization of the EKG artifact signal is achieved when the signal at the AMP OUT jack 105 is between approximately 1.00 - 2.00 volts peak-to-peak, preferably between approximately 1.25 - 1.75 volts peak-to-peak and more preferably between approximately 1.45 - 1.55 volts peak-to-peak.
  • the duration of a blanking pulse comprises approximately between 100 - 140 milliseconds, preferably between approximately 110 - 130 milliseconds and more preferably between approximately 119 - 121 milliseconds.
  • a blanking pulse duration may be either increased or decreased by pressing and turning the ADJUST knob 145, wherein the selected blanking pulse duration automatically appears within an LCD window 130.
  • the blanking pulse duration is too short, some of the EKG artifact signal will "leak" into the clean EMG signal before transmission to the moving averager. It is further believed that this phenomenon will be indicated by bumps in the moving average output data.
  • a composite EMG signal is monitored by selecting the MONITOR switch 150 on the EMG monitor front panel, wherein a composite EMG signal is automatically processed to minimize or replace an EKG artifact signal.
  • an LCD window 130 shows a computed heart rate (HR) and a respiratory rate (RR), wherein an EKG light 155 blinks in synchrony with the heart rate.
  • HR computed heart rate
  • RR respiratory rate
  • the proper functioning of one embodiment of a contemplated EMG monitor device comprises the following areas of technical expertise: Input and Amplification: A medical-grade isolation amplifier (i.e., for example, having isolated, differential instrumentation) provides a safe interface for patient- connected electrodes. The composite EMG signal output of the isolation amplifier is high-pass band filtered to remove any direct current components of the recorded signal. The composite EMG signal is then amplified by a programmable-gain amplifier under microcontroller control that results in a standardized signal under a variety of recording situations.
  • the standardized composite EMG signal is then low-pass band filtered and transmitted through a notch filter that removes power line frequency components.
  • Digital Time Delay The standardized composite EMG signal generated according to the above paragraph is next processed by a digital time delay circuit that optimally delays the signal for approximately 50 msec.
  • the digital time delay circuit comprises an interconnected analog-to-digital converter, a microcontroller with an external memory buffer and a digital-to-analog converter.
  • the standardized composite EMG signal is, therefore, delayed within the microcontroller as a digital signal prior to reconstruction into an analog signal.
  • the signal may also be digitally full-wave rectified during the delay process.
  • EKG Blanker and Moving Averager The rectified and delayed composite EMG signal is then transmitted from the digital-to-analog converter to a moving averager circuit via an EKG blanker comprising a microcontroller-controlled analog switch.
  • This analog switch is normally configured to transmit the rectified composite EMG signal from the digital-to-analog converter directly into the moving averager circuit.
  • the analog switch is reconfigured to provide input to the moving averager circuit using the "last known" moving averager circuit output (i.e, the moving averager output is utilized as moving averager input during the blanking interval). This effectively clamps the moving average circuit output signal to the signal detected just prior to the blanking pulse (i.e., without any EKG artifact signal).
  • a microcontroller monitors the real-time signal and automatically generates a blanking pulse upon detection of a threshold average QRS complex.
  • a blanking pulse duration determines the length of time that the analog switch is reconfigured to accept moving averager output data.
  • a predetermined duration of the blanking pulse is selected to sufficiently "envelop" the EKG artifact signal within the delayed EMG signal interval.
  • a gated EMG signal is also provided as an output to verify that the proper interval is being blanked.
  • the EMG monitor device includes a liquid crystal display window to observe operational device conditions including, but not limited to, amplifier gain, amplitude of moving average, etc.
  • the LCD window also may present instructions to the user for setup and operation.
  • the LCD window may also comprise indicators providing visual monitoring of proper operation.
  • An EMG monitor device electronic schematic diagram is presented in Figure 7 and is not intended to limit the present invention but only to illustrate one embodiment of a breathing disorder diagnostic device.
  • a composite EMG signal is detected by skin surface electrodes 1 A - 1C and increased in signal strength by isolation amplifier 2.
  • the composite EMG signal is then processed by low-pass band filter 3 (i.e., having a frequency range of approximately 0.1 - 18 Hz) that preferentially filters the EKG artifact signal and a high-pass band filter 4 (i.e., having a frequency range of approximately 10 Hz) that preferentially filters the composite EMG signal.
  • low-pass band filter 3 i.e., having a frequency range of approximately 0.1 - 18 Hz
  • a high-pass band filter 4 i.e., having a frequency range of approximately 10 Hz
  • the gain of exaggerated EKG artifact signal and composite EMG signal may then be independently adjusted by programmable gain amplifier 5 and programmable gain amplifier 6 (i.e., having gain ranges of approximately 1 - 100X), respectively.
  • Each gain amplifier 5, 6 may receive input from printed integrated circuit microcontroller 7 (i.e., for example, model 16F877), either simultaneously or separately, to provide real-time monitoring and adjustment of their respective signal amplitudes.
  • Microcontroller 7 maintains feed-back loops with both the composite EMG signal and the exaggerated EKG artifact signal via their respective programmable gain amplifiers 5, 6.
  • Exaggerated EKG artifact signal input to microcontroller 7 is received directly from the programmable gain amplifier 5, while composite EMG input to microcontroller 7 is indirectly received from the programmable gain amplifier 6 after further processing by low-pass band filter 8 (i.e., having a frequency range of approximately 4000 Hz) and notch filter 9 (i.e., having a frequency range of approximately 60 Hz).
  • the digital time delay circuit receives input from notch filter 9 wherein the composite EMG signal is first converted into a digital signal by 12-bit A/D converter 10. This digital composite EMG signal is thereafter delayed approximately 50 milliseconds within printed integrated circuit microcontroller 11 (i.e., for example, model 16F877) and reconverted to an analog signal by 12-bit D/A converter 12.
  • the EKG blanker 13 receives the delayed composite EMG signal by analog switch 14.
  • Analog switch 14 is reconfigured to receive output from moving averager 16 (i.e., providing an averaged signal data point over approximately 200 milliseconds of signal duration) upon receipt, and duration, of a blanking pulse generated by microprocessor 7.
  • moving averager 16 i.e., providing an averaged signal data point over approximately 200 milliseconds of signal duration
  • the EKG blanker provides input to moving averager 16 as either: i) a delayed composite EMG signal (absence of blanking pulse) or ii) output from moving averager 16 (presence of blanking pulse).
  • Synchronicity between the blanking pulse and the composite EMG signal is verified by comparing signals received at gated composite EMG output 17 (mediated by analog switch 15 which is also reconfigured by the blanking pulse) with signals received directly from microcontroller 7 at gated blanking pulse output 18.
  • User input controls 20 allow manual gain control and/or alternative mode selection by a direct interface with microprocessor 7.
  • Microprocessor 7 thereby returns status information for user viewing on LCD window 21.
  • the 16F877 microcontroller in the above example has port assignment configurations as listed in Table I.
  • ERROR led dta var portc 4 pot data elk var portc 5 pot clock cl var portc 6 analog sw Cl, gated EMG c2 var portc 7 analog sw C2 , M.A.
  • EMG_gain var byte EMG amp gain value, 0 - 255
  • the present invention contemplates novel software programs for the following functions: Startup And Initialization (Table III); Main Program (Table IV); Auto Setup Mode (Table V); Auto Monitoring Mode (Table VI); Moving Average Peak Detection (Table VII); Respiratory Rate Measurement (Table VIII); Manual Gain Set (Table IX); Blank Pulse Duration Set (Table X); Subroutines (Table XI); Rotary Encoder (Table XII); Welcome Screen (Table XIII); Main Monitoring Screen (Table IVX); Auto Setup Screen (Table XV); Manual Setup Screen (Table XVI); Blank Pulse Duration Setup Screen (Table XVII); Interrupt Service Routine (Table XVIII); and Counter Updates & Test Bit Toggles (Table IXX).
  • TRISA %111111 configure ports
  • ADCON0 0 set porta & port e for digital I/O
  • EMG_gain EMG_gain min 252 adjust EMG channel gain
  • EMG_gain EMG_gain max 3 if peak_EMG ⁇ targe _EMG then lcdout I, 208, " ⁇ L0>”
  • EMG_gain ⁇ MG_gain + 2 else lcdout I, 208, " ⁇ HI>”
  • EMG_gain EMG_gain - 2 endif
  • ECG_gain ECG_gain min 252 adjust EMG channel gain
  • first bit is stack select bit (0) shiftout dta, elk, 1 , [pot_data ⁇ 16] composite 16 bit data for pot
  • Table XIII Welcome Screen gosub clear_lcd lcdout I, 128, " EMG-1 Monitor” lcdout I, 192, " Version “, # (version / 100) ,”.”,# (version // 100) lcdout I, 148, " .(c) CWE,INC.” pause 2000 ® bsf _led_pwr pause 250
  • Table XVIII Interrupt Service Routine movwf wsave Save the W register swapf STATUS , clrf STATUS Point to bank 0 movwf ssave Save STATUS with reversed nibbles movf PCLATH, W Save PCLATH movwf psave
  • Table IXX Counter Update And Test Bit Toggle mtserv interrupt service routine bcf PIR1, 0 clear tmrl int flag TMR1IF incf _timelb, f increment time count lo byte btfsc status, 2 zero set? N > 255?
  • incf etimehb f yes, increment hi byte incf ftimelb, f increment timer f btfsc status, zero set? N > 255? incf _ftimehb, f yes, increment hi byte incf _gtimelb, f increment timer g btfsc status, 2 zero set? N > 255?
  • EXAMPLE 1 Diaphragmatic Movements And Inspiratory Effort Correlations In Awake Subjects This example presents data showing the relationship between ⁇ maEMGdi and ⁇ Pes in awake subjects.
  • the study population of 8 subjects consisted of 7 health care professionals having no sleep disordered breathing and one sleep disordered breathing patient. Each subjects' anthropometric data is detailed in Table 1.
  • the study protocol was approved by the institutional review boards of the DVA Medical Center - Northport and Stony Brook University and informed consent was obtained from each subject.
  • Esophageal manometry was performed with a saline - filled catheter system and placed in the middle-third of the esophagus.
  • Baydur et al "A Simple Method For Assessing the Validity Of The Esophageal Balloon Technique” Am RevRespirDis 126:788-791 (1982).
  • An 8 French 42" infant feeding tube (Cat. # 85774, Malinckrodt Inc, St. Louis, MO) with lateral ports in the distal end (i.e., over the terminal 1 centimeter) was connected to a calibrated, disposable, arterial line pressure transducer (Model # 041576504A, Argon Medical, Athens, TX).
  • the infant feeding tube was passed transnasally and swallowed until the distal end was in the stomach (determined by a positive pressure deflection with a strong sniff).
  • the catheter was then gradually retracted until a strong sniff first resulted in a negative deflection (i.e., showing that the distal 1 cm of the catheter was at the level of the diaphragm). From that point, the catheter was retracted an additional 5 centimeters and fastened to the nose with surgical tape. Observation of left atrial pressure artifact in the catheter trace was used to validate the position of the catheter tip in the middle third of the esophagus.
  • the surface maEMGdi was monitored using 2 disposable electrodes (type SP-00- S, Medicotest A/S, Denmark) applied to the skin after very mild dermal abrasion with gauze. Positioning of the electrodes is illustrated in Figure 5. Specifically, the electrodes were positioned in the lowest right intercostal space intersecting the anterior axillary line (the 7th intercostal space) and the next inferior right intercostal space in the mid-axillary line (the 8th intercostal space).
  • the EMG signal was band-pass filtered (10-1000 Hz), amplified (Model 7P511 EEG amplifier, Grass Instrument Co, Quincy, MA), full- ave rectified and passed through a low-pass moving averager with a time constant of 200 msec (Model 821, CWE Inc, Ardmore, PA) to obtain the maEMGdi.
  • the EKG artifact in the maEMGdi was attenuated using a blanker device which senses the EKG signal and replaces the EKG artifact with an adjacent portion of the preceding moving average EMG signal (Model SB-1 EKG blanker, CWE Inc., Ardmore, PA).
  • each of the 8 subjects breathed through a nasal mask connected with a pneumotachygraph (Hans Rudolph, Kansas City, MO).
  • nasal airflow, esophageal pressure (Pes) and maEMGdi were recorded.
  • Figure 8 demonstrates a polygraph recording of the protocol for one subject.
  • Figure 9 plots ⁇ maEMGdi against ⁇ Pes for each of the 8 subjects and demonstrates that there is a linear relationship between ⁇ Pes and ⁇ maEMGdi for each subject. There are differences between subjects, however, in the slope of the relationship. For all 8 subjects, ⁇ Pes and ⁇ maEMGdi appear to be linearly related as shown in Table 3.
  • the slopes of the regression lines vary. On average, the y-intercept of the regression lines is near zero suggesting a proportional relationship (i.e., a positive correlation) between ⁇ Pes and ⁇ maEMGdi. In addition, for three of the subjects, the regression line departs modestly from the origin (i.e., the point '0,0'). The data illustrate that ⁇ Pes and ⁇ maEMGdi are positively correlated where increasing ⁇ maEMGdi correlates with increasing ⁇ Pes.
  • the high correlation coefficients between the two parameters mean that over a wide range of values for ⁇ Pes, the change of ⁇ maEMGdi for a given change in ⁇ Pes is fairly constant.
  • the above observation that the slope of the regression differs substantially between subjects prevents calculation of a population estimate of the value of ⁇ Pes from ⁇ maEMGdi measurements. Practically, this means that this method for measuring inspiratory effort based on ⁇ maEMGdi measurements is subject-specific.
  • Figure 10 plots ⁇ maEMGdi against ⁇ Pes for each of the 3 subjects who performed the protocol supine and recumbent upon the right and left sides. As discussed above, the slopes of the regression in all three positions were similar and the correlation coefficients of the regression were high. See Table 2.
  • the graphs of Subjects 7 and 8 demonstrate little change in the relationship with body position while the graph of Subject 3 demonstrates a deviation from the proportionality of the signal excursions in the supine position when compared to recumbent positions on the left or right sides.
  • changes in body position did not interfere with the correlation between ⁇ Pes and ⁇ maEMGdi.
  • the precise relationship between the two parameters may vary with body position.
  • this example demonstrates a high correlation and approximate proportionality between ⁇ maEMGdi and ⁇ Pes, it is suggested that ⁇ maEMGdi cannot be used to predict ⁇ Pes for any one subject. This observation is not surprising because of the nature of the relationship between diaphragmatic contraction and pleural pressure changes.
  • This example provides data on four sleeping subjects that have been diagnosed with a sleeping disorder during non-rapid eye movement (NREM) stages of sleep. Specifically, the data shows a positive correlation between esophageal pressure and maEMGdi.
  • the subjects were tested according to the procedure described in Example 1, with the exception that all subjects were administered positive pressure ventilation with a standard commercially available CPAP device.
  • FIG. 12 shows one sixty (60) second data tracing from data collected with an EMG-1 diagnostic device as contemplated by the present invention. Decreased maEMGdi, decreased Pes and decreased inspiratory flow were positively correlated. Specfically, an inspection of the timeframe between 12:11:35 AM and 12:11:50 AM clearly shows that a reduction in inspiratory flow (Flow tracing) positively correlated with a reduced maEMGdi (EMG averager tracing) and a reduced esophageal pressure (Pesoph tracing). These data allow the conclusion that the subject has an upper airway resistance.
  • Flow tracing a reduction in inspiratory flow
  • EMG averager tracing EMG averager tracing
  • Pesoph tracing reduced esophageal pressure

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Medical Informatics (AREA)
  • Biophysics (AREA)
  • Pathology (AREA)
  • Engineering & Computer Science (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Physics & Mathematics (AREA)
  • Molecular Biology (AREA)
  • Surgery (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Cardiology (AREA)
  • Measurement And Recording Of Electrical Phenomena And Electrical Characteristics Of The Living Body (AREA)
  • Measurement Of The Respiration, Hearing Ability, Form, And Blood Characteristics Of Living Organisms (AREA)

Abstract

L'invention concerne le diagnostic et le traitement de troubles respiratoires chez des sujets endormis ou éveillés. Un dispositif électrique peut être utilisé pour surveiller et traiter un signal d'électromyogramme diaphragmatique comme un indicateur d'un effort inspiratoire. Certains troubles du sommeil se manifestent par un effort inspiratoire accru. La présente invention constitue une amélioration par rapport à l'utilisation actuelle des signaux d'électromyogramme diaphragmatiques dans le diagnostic des troubles du sommeil en ceci qu'elle permet d'éliminer efficacement les signaux d'électrocardiogramme concomitants. Ledit dispositif électrique comprend également un système permettant de surveiller et d'enregistrer des données d'un patient (par exemple, à domicile), de sorte qu'un trouble respiratoire puisse être diagnostiqué ultérieurement par un clinicien.
PCT/US2005/009492 2004-03-29 2005-03-22 Procede et dispositif non invasif permettant de detecter un effort inspiratoire WO2005096924A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
EP05730716A EP1729636A1 (fr) 2004-03-29 2005-03-22 Procede et dispositif non invasif permettant de detecter un effort inspiratoire
AU2005231133A AU2005231133A1 (en) 2004-03-29 2005-03-22 Non-invasive method and device for detecting inspiratory effort
CA002559857A CA2559857A1 (fr) 2004-03-29 2005-03-22 Procede et dispositif non invasif permettant de detecter un effort inspiratoire

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US55732404P 2004-03-29 2004-03-29
US60/557,324 2004-03-29

Publications (1)

Publication Number Publication Date
WO2005096924A1 true WO2005096924A1 (fr) 2005-10-20

Family

ID=35124781

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2005/009492 WO2005096924A1 (fr) 2004-03-29 2005-03-22 Procede et dispositif non invasif permettant de detecter un effort inspiratoire

Country Status (4)

Country Link
EP (1) EP1729636A1 (fr)
AU (1) AU2005231133A1 (fr)
CA (1) CA2559857A1 (fr)
WO (1) WO2005096924A1 (fr)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102007031017B3 (de) * 2007-07-04 2009-02-12 Dräger Medical AG & Co. KG Verfahren zum Betreiben einer Anästhesie- oder Beatmungsvorrichtung mit Triggerfunktion und Vorrichtung hierzu
CN102949770A (zh) * 2012-11-09 2013-03-06 张红璇 一种体外膈肌起搏与呼吸机协同送气的方法及其装置
DE102012003509A1 (de) * 2012-02-22 2013-08-22 Dräger Medical GmbH Beatmungssystem
CN104939830A (zh) * 2014-03-27 2015-09-30 广州医科大学附属第一医院 采用表面电极反映上气道阻力
CN105916440A (zh) * 2013-12-18 2016-08-31 圣米高医院 用于验证病人的吸气肌活动的方法和系统、以及使用该方法和系统的机械通气系统
WO2016155876A1 (fr) * 2015-03-31 2016-10-06 Drägerwerk AG & Co. KGaA Amplificateur de signal de mesure et procédé d'alimentation électrique d'un amplificateur de signal de mesure
WO2017208204A1 (fr) * 2016-06-03 2017-12-07 Universidad Eia Procédé et appareil de détection de l'apnée
WO2018001929A1 (fr) 2016-06-30 2018-01-04 Koninklijke Philips N.V. Appareil de traitement destiné au traitement d'un signal physiologique
EP3381354A1 (fr) * 2017-03-31 2018-10-03 Koninklijke Philips N.V. Procédés et système de traitement de signal emg
WO2021063601A1 (fr) 2019-10-02 2021-04-08 Drägerwerk AG & Co. KGaA Procédé et dispositif pour déterminer un signal respiratoire et/ou cardiogénique
CN113967024A (zh) * 2021-12-22 2022-01-25 广州国家实验室 去心电信号的肌电信号处理方法和装置

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU2016418245B2 (en) * 2016-08-01 2020-07-16 Med-El Elektromedizinische Geraete Gmbh Respiratory triggered parasternal electromyographic recording in neurostimulators

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5524632A (en) * 1994-01-07 1996-06-11 Medtronic, Inc. Method for implanting electromyographic sensing electrodes

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5524632A (en) * 1994-01-07 1996-06-11 Medtronic, Inc. Method for implanting electromyographic sensing electrodes

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8201558B2 (en) 2007-07-04 2012-06-19 Draeger Medical Gmbh Method for operating an anesthesia or ventilation apparatus having a trigger function and device therefor
DE102007031017B3 (de) * 2007-07-04 2009-02-12 Dräger Medical AG & Co. KG Verfahren zum Betreiben einer Anästhesie- oder Beatmungsvorrichtung mit Triggerfunktion und Vorrichtung hierzu
US9968749B2 (en) 2012-02-22 2018-05-15 Drägerwerk AG & Co. KGaA Respiration system
DE102012003509A1 (de) * 2012-02-22 2013-08-22 Dräger Medical GmbH Beatmungssystem
FR2986971A1 (fr) * 2012-02-22 2013-08-23 Draeger Medical Gmbh Systeme de ventilation
CN103285478A (zh) * 2012-02-22 2013-09-11 德尔格医疗有限责任公司 呼吸系统
DE102012003509B4 (de) 2012-02-22 2020-06-10 Drägerwerk AG & Co. KGaA Beatmungssystem
CN102949770A (zh) * 2012-11-09 2013-03-06 张红璇 一种体外膈肌起搏与呼吸机协同送气的方法及其装置
US10517528B2 (en) * 2013-12-18 2019-12-31 St. Michael's Hospital Method and system for validating inspiratory muscle activity of a patient, and mechanical ventilation system using the same
US20160310069A1 (en) * 2013-12-18 2016-10-27 St. Michael's Hospital Method and system for validating inspiratory muscle activity of a patient, and mechanical ventilation system using the same
CN105916440A (zh) * 2013-12-18 2016-08-31 圣米高医院 用于验证病人的吸气肌活动的方法和系统、以及使用该方法和系统的机械通气系统
CN104939830A (zh) * 2014-03-27 2015-09-30 广州医科大学附属第一医院 采用表面电极反映上气道阻力
WO2016155876A1 (fr) * 2015-03-31 2016-10-06 Drägerwerk AG & Co. KGaA Amplificateur de signal de mesure et procédé d'alimentation électrique d'un amplificateur de signal de mesure
US11089986B2 (en) 2015-03-31 2021-08-17 Drägerwerk AG & Co. KGaA Measurement signal amplifier and a method for supplying energy to a measurement signal amplifier
WO2017208204A1 (fr) * 2016-06-03 2017-12-07 Universidad Eia Procédé et appareil de détection de l'apnée
WO2018001929A1 (fr) 2016-06-30 2018-01-04 Koninklijke Philips N.V. Appareil de traitement destiné au traitement d'un signal physiologique
US11083404B2 (en) 2016-06-30 2021-08-10 Koninklijke Philips N.V. Processing apparatus for processing a physiological signal
EP3381354A1 (fr) * 2017-03-31 2018-10-03 Koninklijke Philips N.V. Procédés et système de traitement de signal emg
WO2018178326A1 (fr) * 2017-03-31 2018-10-04 Koninklijke Philips N.V. Procédés et système de traitement d'un signal emg
US11596340B2 (en) 2017-03-31 2023-03-07 Koninklijke Philips N.V. Methods and system for processing an EMG signal
WO2021063601A1 (fr) 2019-10-02 2021-04-08 Drägerwerk AG & Co. KGaA Procédé et dispositif pour déterminer un signal respiratoire et/ou cardiogénique
CN113967024A (zh) * 2021-12-22 2022-01-25 广州国家实验室 去心电信号的肌电信号处理方法和装置

Also Published As

Publication number Publication date
AU2005231133A1 (en) 2005-10-20
CA2559857A1 (fr) 2005-10-20
EP1729636A1 (fr) 2006-12-13

Similar Documents

Publication Publication Date Title
WO2005096924A1 (fr) Procede et dispositif non invasif permettant de detecter un effort inspiratoire
KR100446133B1 (ko) 가스공급시스템
US6936011B2 (en) Analysis of sleep apnea
US9014819B2 (en) Autonomic arousal detection system and method
CN110035691B (zh) 用于测量睡眠呼吸暂停的方法和设备
DE112004001954B4 (de) Vorrichtung zur Steuerung der Atmung eines Patienten
US6363270B1 (en) Monitoring the occurrence of apneic and hypopneic arousals
US7283875B2 (en) Nerve stimulation device
EP1670547B1 (fr) Systeme de surveillance de patient
US8380296B2 (en) Automatic activation of medical processes
US6425861B1 (en) System and method for monitoring and controlling a plurality of polysomnographic devices
US20080139948A1 (en) Use of external respiratory therapy device to detect cardiac electrical activity
US20080319277A1 (en) Sleep disorder monitoring and diagnostic system
US20070282215A1 (en) Detection of disordered breathing
JP2001516253A (ja) 呼吸波形の神経と筋肉の呼吸との関りについて呼吸波形を分析する手段
JP5410970B2 (ja) 哺乳動物に対して使用される人工呼吸器の調節の不具合を検出するための装置
JP2009542391A5 (fr)
Sharp et al. Comparison of diaphragm EMG centroid frequencies: esophageal versus chest surface leads
CN108175406A (zh) 一种治疗中枢性睡眠呼吸暂停症的方法及装置
AU2021103840A4 (en) Development of a Screening tool for Sleep Apnea for experts in clinical setups
Grippo et al. Respiratory-related evoked potential and upper airway transmural pressure change by using the negative expiratory pressure (NEP) device
Chokroverty Check for Polysomnographic Recording Technique Sudhansu Chokroverty and Sushanth Bhat
Riha Methods of different sleep tests
Funsten et al. Evaluation of respiratory disorders during sleep
Chokroverty et al. Patient Preparation and Laboratory Environment

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SM SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): BW GH GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 2559857

Country of ref document: CA

WWE Wipo information: entry into national phase

Ref document number: 2005231133

Country of ref document: AU

NENP Non-entry into the national phase

Ref country code: DE

WWW Wipo information: withdrawn in national office

Country of ref document: DE

ENP Entry into the national phase

Ref document number: 2005231133

Country of ref document: AU

Date of ref document: 20050322

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 2005730716

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 2005231133

Country of ref document: AU

WWP Wipo information: published in national office

Ref document number: 2005730716

Country of ref document: EP