Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
  • A61M16/021—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes operated by electrical means
  • A61M16/022—Control means therefor
  • A61M16/024—Control means therefor including calculation means, e.g. using a processor
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
  • A61M16/06—Respiratory or anaesthetic masks
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
  • A61M16/0003—Accessories therefor, e.g. sensors, vibrators, negative pressure
  • A61M2016/003—Accessories therefor, e.g. sensors, vibrators, negative pressure with a flowmeter
  • A61M2016/0033—Accessories therefor, e.g. sensors, vibrators, negative pressure with a flowmeter electrical
  • A61M2016/0039—Accessories therefor, e.g. sensors, vibrators, negative pressure with a flowmeter electrical in the inspiratory circuit
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M2205/00—General characteristics of the apparatus
  • A61M2205/33—Controlling, regulating or measuring
  • A61M2205/3331—Pressure; Flow
  • A61M2205/3344—Measuring or controlling pressure at the body treatment site

Definitions

• the invention relates to a method for controlling an apparatus for supplying air pressure to a patient suffering from sleep disorders.
• the invention also relates to an apparatus for supplying air pressure to a patient suffering from sleep disorders.
• US-A-5,458,137 describes a method and device for controlling breathing in sleep disorders, which use multiple and variable pressure levels.
• a pressure source supplies compressed respiratory gas at a relatively low pressure to the user's airways.
• Pressure sensors monitor pressures and convert them into electrical signals.
• Electrical signals are filtered and processed to extract specific characteristics such as duration and energy levels.
• the microprocessor If these characteristics exceed selected thresholds of duration and energy level beyond a minimum period of time, the microprocessor indicates the presence of a respiratory sleep disorder. If a selected number of these events appear for a selected period of time, the microprocessor adjusts the pressure supplied by the source.
• Document US-A-5 490 502 describes a method and an apparatus for optimizing the positive pressure controlled in order to minimize the air flow coming from a generator while ensuring that the limitation of flow in the patient's airways does not not produce.
• the system determines an action to be carried out for adjusting the positive pressure commanded.
• the pressure is increased, decreased or maintained depending on whether the flow limitation has been detected and depending on the previous actions implemented by the system.
• the invention aims to improve the methods and devices of the state of the art, to automatically and continuously adapt the pressure delivered to the state of the patient and to prevent and prevent the appearance of disorders.
• a first object of the invention is a method of controlling an apparatus for supplying air pressure to a patient suffering from sleep disorders such as apneas.
• a second object of the invention is an apparatus for supplying air pressure to a patient suffering from sleep disorders such as apnea, implementing the method of supply.
• the patient wears a mask through which pressurized air is supplied to his upper airways by the device.
• a control algorithm using a device output rate signal for the detection of apnea, hypopnea, rate limitation events, leaks, and using the analysis.
• pressure information to determine the presence of snoring, also called acoustic vibrations.
• the pressure supplied to the patient's upper airway by the device can be kept constant, increased or decreased depending on the determination of the event that was performed by the control algorithm.
• This predetermined minimum apnea detection time is for example equal to a time constant, for example 10 s, added to a proportionality factor multiplied by the calculated average breathing time, this factor being for example equal to 5/8.
• the output flow signal is amplified and filtered to determine the presence or absence of heart oscillations.
• cardiac oscillations were detected during the last elapsed time interval, for example equal to 5 s, then the apnea is classified as central and no command occurs in the algorithm.
• the apnea is classified as obstructive, and the pressure is increased by a predetermined value once and, during the same apnea, twice more regularly, by example every 15 s.
• the control algorithm compares variations in peak-to-peak flow during the patient's last breath compared to a predetermined number of previous breaths, for example equal to 8.
• a classification is made into: - normal breathing, if the last peak-to-peak flow value is within a determined range compared to the average value over the previous 8 breaths, for example from 40% to 150% or 140% of these;
• a hypopnea determination is carried out if the detection of hypopneic respiration has occurred for at least a determined time, for example 10 s, and ends after a determined number of normal or hyperpneic breaths, for example equal to 2.
• hypopnea leads to a determined increase in pressure, for example of 1 cm H2O first, then, during the same hypopnea, to an increase in pressure of another determined value and this regularly, for example of 0, 5 cm H2O every two hypopneic breaths.
• the control algorithm analyzes and compares, breath by breath, the waveform of the respiratory flow with a sinusoidal waveform of the same period and the same slope.
• each breath is first classified as normal, intermediate or limited flow.
• a final classification based on the combination of the classification of flow and the occurrence of snoring changes the classification of breaths from normal to intermediate, respectively from intermediate to limited flow breathing.
• a treatment is decided when a certain number, for example 2, successive breaths at a limited rate or a certain number, for example 5, of successive intermediate breaths take place after for example two normal breaths.
• This treatment causes a determined increase in pressure, repeated regularly a certain number of times, for example 0.3 cm H2O three times every two breaths. For each breath, the pressure signal is amplified and filtered to detect the presence or absence of acoustic vibrations or snoring.
• a valid snoring determination is made by the control algorithm, if the detected acoustic vibration has occurred at least for a certain time, for example 7% of the average duration of the last three breaths, and with a shorter period to a factor proportional to this average time, for example 120% of it.
• the algorithm increases the pressure by a determined value, for example by 1 cm H2O, if the last command due to a snoring occurred for more than a determined time, for example 1 minute.
• An average leak is determined to be equal to the average flow during breathing.
• the control algorithm continuously compares the current leak to a leak limit, which limit can be adjusted from the pressure.
• the algorithm After detecting an apnea or a snoring event or a hypopnea command or a treatment decision, the algorithm will decrease the pressure by a determined value, for example by 0.5 cm H2O, in a first step after a determined time, for example 5 minutes, and regularly for the following decreases, for example every minute.
• a determined holding pressure for example 8 cm H2O is supplied by the device if no breath has been detected for a determined time, for example two minutes, or if the pressure supplied has been greater than or equal to a value determined for a determined time, for example at 17 cm H2O for 10 or 30 minutes.
• An advantage of the method is an automatic adaptation of the detection criteria to the respiratory characteristics of the patient.
• any modification of the respiratory rhythm is taken into account by the algorithm to carry out the detection.
• Figure 1 is a diagram showing the apparatus for supplying air pressure to the patient.
• FIG. 2 represents a decision-making algorithm for a first pressure increase command.
• FIG. 3 represents an algorithm for indicating the appearance of disorders.
• Figure 4 shows a breathing qualification algorithm
• FIG. 5 represents an algorithm for detecting central and obstructive apnea and for controlling pressure as a function of the result of these detections, as well as an algorithm for reducing pressure according to the previous appearance or not of events representative of disorders of the sleep.
• FIG. 6 represents an algorithm for qualifying a normal ventilation cycle, hyperventilation or hypoventilation.
• FIG. 7 represents an algorithm for detecting hypopneic respiration.
• FIG. 8 represents an algorithm for detecting hyperpneic respiration.
• Figure 9 shows a normal breathing detection algorithm.
• Figure 10 shows a high pressure detection algorithm
• FIG. 11 represents an algorithm for detecting mask leakage.
• FIG. 12 represents an algorithm for detecting acoustic vibrations.
• FIG. 13 represents an algorithm for reducing pressure in the event of detection of acoustic vibrations.
• the apparatus for supplying air pressure to a patient comprises a central pressure treatment and control unit U, a controlled MPD module for supplying pressure, an MVA mask for the patient's upper airways , a CF duct for supplying air pressure from the MPD module to the MVA mask.
• the air flow supplied to the patient and the air pressure prevailing in the MVA mask are measured by a CDAF sensor of the supplied air flow, connected to the central unit U and by a CPM pressure sensor in the mask.
• MVA connected to the central unit U.
• a BLN indicator of disturbance appearance is placed in a first ON state of appearance of disorders, if the appearance of one or more of the events representative of sleep disorders is determined.
• the BLN indicator is put in a second OFF state of absence of disorders, if the appearance of the events representative of sleep disorders is not determined.
• command C1 commands a first determined increase in the supplied air pressure, when, at the same time:
• the first CCAR number is greater than a first predetermined whole RP number; • the second number CCON corresponds to another or more second predetermined whole numbers N;
• the third RC number is greater than or equal to a third predetermined integer X.
• the first CCAR number is greater than a first predetermined whole RP number
• the third RC number is greater than or equal to a third predetermined integer X.
• the second integers N are between 1 and 300. In another embodiment, the second integers N are the first three multiples of a determined integer No.
• the second integers N are 2, 4 and 6 respectively, No being equal to 2.
• the first predetermined integer RP is between 1 and 255.
• the first predetermined integer RP is equal to 10.
• the third predetermined integer X is between 1 and 100.
• the third predetermined integer X is equal to 1.
• the first determined command C1 for increasing the pressure is less than + 10 mbar.
• the first determined command C1 to increase pressure is substantially equal to + 0.3 mbar.
• the first and third CCAR numbers are reset to 0; CR of valid respiratory cycles counted and passages counted, after the second count CCON counted of valid cycles has reached the greater of the second predetermined integers N.
• the second number counted CCON is reset to 0 when the BLN indicator goes from the second OFF state to the first ON state.
• the predetermined valid respiratory cycle corresponds to a maximum respiratory flow greater than a predetermined flow value such as 50 ml / s, to a inspiratory volume greater than a predetermined volume value such as 0.05 I and an absence of saturation during flow detection.
• an ER state variable is initialized when the device is switched on to a third state d absence of NIR processing and the BLN indicator in the second OFF state.
• the respiratory cycles are qualified as belonging to different categories such as limited flow cycle, intermediate cycle, normal cycle and invalid cycle, each corresponding respectively to weightings RSV0, REVO; RSV1, REV1; RSV2, REV2; 0, 0;
• weights of the category of the cycle currently qualified are assigned to first and second SV accumulators; Weighting EV;
• the ER state variable is returned to the third NIR state and the BLN indicator to the second OFF state and a first FLC counter is initialized to a predetermined value.
• the state of the state variable ER corresponds to the fourth state PR and • if the value of the first accumulator SV is less than its first comparative value, the first counter FLC is reset to its predetermined value, the variable d 'is reset ER state and the BLN indicator respectively in the third and second NIR states; OFF; • if the value of the first accumulator SV is substantially equal to its first comparative value, action is dispensed with and one passes to the next test;
• the first FLC counter is made to take its previous value added with the value of the first accumulator SV and if then the value of the first FLC counter is greater than or equal to a stop high predetermined RMS:
• the second counter NC is made to take its previous value added to the value of the second EV accumulator and
• the second counter NC • if then the value of the second counter NC is greater than or equal to a lower stop RME, it resets the state variable ER and the indicator BLN to the third and second NIR states respectively; OFF and the first and second FLC counters are reset; NC to their respective predetermined values;
• the BLN indicator is set to its first ON state
• the weightings RSV2, REV2; RSV1, REV1; RSVO, REVO; 0, 0 corresponding to the normal cycle, intermediate cycle, limited flow cycle and invalid cycle are respectively substantially equal to -1; 1; 5 and 0 for the first SV accumulator and are respectively substantially equal to 1; -1; -1 and 0 for the second EV accumulator.
• the first and second comparative values and the predetermined initialization values of the first and second FLC counters; NC are each substantially equal to 0.
• RMS high and low stops; RME are respectively substantially equal to 10 and 2.
• the predetermined valid respiratory cycle corresponds to a maximum inspiratory flow greater than a predetermined flow value such as 50 ml / s, to an inspiratory volume greater than a predetermined volume value such as 0.05 I, to a lack of saturation during flow detection, at a measured inspiratory time comprised in a predetermined interval such as from 0.5 s to 6 s and at a measured duration of respiratory cycles comprised in another predetermined interval such as from 1.5 s to 20 s .
• a surface area criterion CS is calculated proportional to the ratio of the area delimited by the inspiratory curve to the area delimited by the equivalent sinusoidal curve, each taken over the same time interval, included in the inspiratory phase of the measured respiratory cycle ;
• a correlation criterion CC is calculated between the inspiratory curve of the measured inspiratory cycle and the equivalent sinusoidal curve
• the measured respiratory cycle is qualified as normal and otherwise, it is called a limited flow cycle.
• the measured respiratory cycle has been qualified as a limited flow cycle, • if the calculated surface criterion CS is greater than a third predetermined expert LE limit, the measured respiratory cycle is normalized, • or otherwise, If the surface area criterion CS calculated is greater than a fourth predetermined limit LD of flow rate, the measured respiratory cycle of intermediate is requalified,
• the second area limit LS, the fourth rate limit LD and the third expert limit LE being predetermined in ascending order.
• the predetermined characteristics of the equivalent sinusoidal curve include a half-period substantially equal to the inspiratory time measured and a slope at the origin substantially equal to that of the inspiratory curve when it reaches substantially one third of its maximum amplitude.
• the calculated surface criterion CS is substantially equal to a hundred times the ratio of the areas taken each from substantially a quarter to three quarter of the duration of the inspiratory phase of the respiratory cycle measured.
• the calculated correlation criterion CC is substantially equal to the maximum of a hundred times the correlation coefficients between the inspiratory curve and the equivalent sinusoidal curve taken respectively on the second half of the inspiratory phase and on the whole of the latter.
• the first, second, fourth and third LN limits; LS; LD; LE being respectively between 45 and 100; 0 and 100; 0 and 100; 0 and 100 and being for example substantially equal to 87; 40; 60 and 90 respectively.
• the algorithm represented in FIG. 5 is carried out during each of several (NINT) consecutive predetermined time intervals TACG ' ).
• the predetermined consecutive TACG time intervals are those included in a predetermined apnea detection PDAC period.
• the oscillations of the measured flow curve are detected, which are of frequencies included in a frequency range P2.
• the second threshold SQAC for qualification of central apnea is between 0 and 50, and is for example substantially equal to 10.
• the predetermined consecutive TACG) time intervals correspond to ten (NINT) consecutive time intervals of each substantially 100 ms, the PDAC apnea detection period corresponding substantially to 1 s.
• the second C2 pressure increase command is between 1 and 10 mbar and is for example substantially equal to + 1 mbar.
• the number (D + 1) of PDAC apnea detection periods, over which the CAC (i) numbers counted for central apnea detection are calculated is substantially equal to 5.
• the second range P2 of oscillation frequency is between substantially 2.5 and 47 Hz.
• the CAC (i) counted numbers of central apnea detections are reset to 0 when the device is switched on.
• FIG. 5 There is also shown in FIG. 5 an algorithm for reducing pressure according to the previous appearance or not of events representative of sleep disorders.
• the pressure P measured is compared with a predetermined pressure value MPL.
• the fourth pressure reduction command C4 is such that it causes a greater pressure reduction per unit of time than that caused by the third pressure command C3.
• the fourth command C4 for pressure reduction is substantially -0.5 mbar / 1 minute and the third command C3 for pressure reduction is substantially -0.5 mbar / 5 minutes, the comparative MPL value of pressure is between 4 and 19 mbar and is for example substantially equal to 17 mbar.
• This pressure reduction algorithm as a function of the appearance or not of events is implemented after that of detection of central and obstructive apneas as represented in FIG. 5 but is also implemented, in embodiments not shown, after other algorithms such as:
• the respiratory cycles are qualified as hyperventilated, hypoventilated or cycles with normal ventilation and pressure commands are generated according to the qualifications performed.
• the average amplitude AM is calculated over a fourth predetermined number Y4 of previous respiratory cycles.
• C6 commands a sixth predetermined increase in pressure; • after the end of a sixth predetermined number Y6 of respiratory cycles, greater than the fifth number Y5, according to the fifth command C5 of increase in pressure, a seventh increase in pressure is commanded by a command C7.
• the CTHO hypopnea time counter is initialized to 0 when the device is switched on.
• the fourth determined number Y4 of respiratory cycles for calculating average amplitude is substantially equal to 8.
• the first predetermined factor FHO for hypopnea is between 1 and 100% and is for example substantially equal to 40%.
• the minimum TMHO hypopnea time is between 1 s and 25 s and is for example substantially equal to 10 s.
• the fifth and sixth predetermined numbers Y5; Y6 of respiratory cycles are substantially equal to 2 and 4 respectively.
• the fifth predetermined pressure increase C5 is between 0.1 mbar and 10 mbar and is for example substantially equal to + 1 mbar.
• the sixth and seventh increases C6; C7 predetermined pressure are each less than the fifth command C5 and are for example each substantially equal to half of the fifth increase C5 pressure.
• the TCM time of average respiratory cycles is calculated over a seventh predetermined number Y7 of previous cycles.
• the measured duration TC of the last cycle is greater than an eighth predetermined number Y8 multiplied by the average respiratory cycle time calculated TCM, the measured duration TC of the last cycle, multiplied by a second factor F2, is added to the time counter in hypopnea CTHO hypopnea.
• the measured amplitude of the last respiratory cycle measured is greater than a third factor F3 of hyperventilation, greater than the first factor FHO of hypopnea, multiplied by the calculated average amplitude AM, we qualify the last hyperventilated cycle, we increment by one a counter of hyperventilated cycles CCH, we reset to 0 a CCN counter of cycles with normal ventilation and
• the second factor F2 multiplied by the duration of the last respiratory cycle TC is added to the CTHO counter for time in hypopnee, " and if not, the CTHO counter in hypopnea is reset to 0; then a counter CCHO of hypoventilated cycles is reset to 0 and the mean amplitude AM of respiratory cycle is calculated on the predetermined number Y4 of previous respiratory cycles.
• the CCH counter for hyperventilated cycles is reset to 0 and increments the CCN counter of cycles with normal ventilation by one, and • if the value of the CCN counter of cycles with normal ventilation is greater than or equal to a tenth predetermined number Y10,
• the second factor F2 multiplied by the duration of the last TC cycle is assigned to the CTHO counter in time in hypopnee and reset at 0 the CCN cycle counter with normal ventilation
• the CTHO counter in hypopnea is reset to 0; then the CCHO counter of hypoventilated cycles is reset to 0 and the average amplitude of the respiratory cycle is calculated on the predetermined number Y4 of respiratory cycles.
• the second factor F2 is substantially equal to 5/8.
• the third hyperventilation factor F3 is between 100% and 200% and is for example substantially equal to 140%.
• the seventh, eighth, ninth and tenth predetermined numbers Y7; Y8; Y9; Y10 are respectively substantially equal to 3; 2; 2; and 2.
• a time counter in high pressure TPH is reset to 0.
• the high pressure value PH is between 10 mbar and 25 mbar and is for example substantially equal to 17 mbar.
• the maximum high pressure time TMPH is between 1 and 100 minutes and is for example substantially equal to 10 minutes or 30 minutes.
• the PSEC safety pressure value is approximately 8 mbar.
• an air leak is measured, substantially equal to the average flow during the patient's breathing. If the measured air leakage is greater than a predetermined NFM leakage level, the pressure increase commands are invalidated.
• NFM A x Pfiltrée + B.
• the predetermined level of leakage NFM is substantially equal to a coefficient of leakage multiplied by a filtered air pressure in the mask, added to a coefficient B additive of leakage, the coefficient A of leakage being between 0 and 10 l / minute.mbar and for example being substantially equal to 2.5 l / minute.mbar.
• the additive leakage coefficient B is between 0 and 100 l / min and is for example substantially equal to 50 l / min.
• This detection is carried out for example by hardware means such as analog or digital filters.
• the time RF1 of presence of oscillations detected between two successive absences of detected oscillations is measured and the time RF0 of absence of oscillations detected between two successive presences of detected oscillations;
• C8 commands an eighth predetermined increase in pressure and resets the elapsed time counter CTAR to 0.
• the acoustic vibration detection and control algorithms in the event of acoustic vibrations are implemented at prescribed time intervals, in particular regularly and for example every 100 ms.
• this counter of the time interval is incremented (INC CTAR) prescribed mentioned above.
• each of the measured times of absence and presence of oscillations detected RFO is reset to 0; RF1.
• each of the measured absence and presence times of 0 is reset to 0 oscillations detected RFO; RF1.
• the predetermined maximum time TCMax is substantially equal to twice the time TCM of average respiratory cycle over the last three measured cycles.
• the prescribed BIP time range; BSP is substantially between 10% and 120% of the calculated average cycle time TCM.
• the minimum oscillation time TMRH is substantially equal to 7% of the calculated average cycle time TCM.
• the prescribed waiting time TAR is between 1 and 30 minutes and is for example substantially equal to 1 minute.
• the eighth command C8 for increasing the pressure is between 0.1 mbar and 10 mbar and is for example substantially equal to 1 mbar.
• the range P1 of oscillation detection frequency is between substantially 30 and 300 Hz.
• the chronology of the detected events is memorized and the memorized chronology is noted, for example after one night.
• the central unit U of the device includes a memory, not shown, which can be written and read with the chronology of the events detected.
• This chronology can be viewed for example on a monitor by reading the contents of the memory, via a computer not shown.

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• Health & Medical Sciences (AREA)
• Emergency Medicine (AREA)
• Pulmonology (AREA)
• Engineering & Computer Science (AREA)
• Anesthesiology (AREA)
• Biomedical Technology (AREA)
• Heart & Thoracic Surgery (AREA)
• Hematology (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Measurement Of The Respiration, Hearing Ability, Form, And Blood Characteristics Of Living Organisms (AREA)

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• 1999
  • 1999-05-21 FR FR9906515A patent/FR2789593B1/fr not_active Expired - Fee Related
• 2000
  • 2000-02-10 US US09/913,237 patent/US6814074B1/en not_active Expired - Lifetime
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  • 2000-02-10 WO PCT/FR2000/000334 patent/WO2000047262A1/fr active Application Filing
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