CA1070816A - Apparatus for the automatic measurement of the arterial pressure of a patient - Google Patents
Apparatus for the automatic measurement of the arterial pressure of a patientInfo
- Publication number
- CA1070816A CA1070816A CA260,786A CA260786A CA1070816A CA 1070816 A CA1070816 A CA 1070816A CA 260786 A CA260786 A CA 260786A CA 1070816 A CA1070816 A CA 1070816A
- Authority
- CA
- Canada
- Prior art keywords
- wall
- pressure
- receiver
- emitter
- chamber
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired
Links
- 230000004872 arterial blood pressure Effects 0.000 title claims abstract description 8
- 238000005259 measurement Methods 0.000 title claims abstract description 8
- 230000000694 effects Effects 0.000 claims description 8
- 210000001367 artery Anatomy 0.000 claims description 7
- 230000035488 systolic blood pressure Effects 0.000 claims description 7
- 230000035487 diastolic blood pressure Effects 0.000 claims description 5
- 208000036366 Sensation of pressure Diseases 0.000 claims 1
- 238000004891 communication Methods 0.000 claims 1
- 230000006854 communication Effects 0.000 claims 1
- 238000000034 method Methods 0.000 description 10
- 239000012528 membrane Substances 0.000 description 4
- 230000010349 pulsation Effects 0.000 description 3
- 238000010009 beating Methods 0.000 description 2
- 206010020772 Hypertension Diseases 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 238000009530 blood pressure measurement Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000003205 diastolic effect Effects 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000001631 hypertensive effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 238000002559 palpation Methods 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 230000004873 systolic arterial blood pressure Effects 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
- A61B8/04—Measuring blood pressure
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/02—Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
- A61B5/021—Measuring pressure in heart or blood vessels
- A61B5/022—Measuring pressure in heart or blood vessels by applying pressure to close blood vessels, e.g. against the skin; Ophthalmodynamometers
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Medical Informatics (AREA)
- Veterinary Medicine (AREA)
- Molecular Biology (AREA)
- Physics & Mathematics (AREA)
- Vascular Medicine (AREA)
- Biophysics (AREA)
- Pathology (AREA)
- Engineering & Computer Science (AREA)
- Surgery (AREA)
- Heart & Thoracic Surgery (AREA)
- Cardiology (AREA)
- Public Health (AREA)
- Biomedical Technology (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Physiology (AREA)
- Hematology (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Radiology & Medical Imaging (AREA)
- Ophthalmology & Optometry (AREA)
- Measuring Pulse, Heart Rate, Blood Pressure Or Blood Flow (AREA)
- Ultra Sonic Daignosis Equipment (AREA)
Abstract
ABSTRACT
This invention relates to an automatic apparatus for the measurement of the arterial pressure which comprises, within a casing, an ultrasonic emitter-receiver as well as an ultrasonic pressure detector. This casing houses also a measuring chamber partly limited at least by a supple and deformable wall intended to enter in contact with the patient.
This invention relates to an automatic apparatus for the measurement of the arterial pressure which comprises, within a casing, an ultrasonic emitter-receiver as well as an ultrasonic pressure detector. This casing houses also a measuring chamber partly limited at least by a supple and deformable wall intended to enter in contact with the patient.
Description
~07V8~6 The present invention has for its ob~ect an apparaeus for the automatic measurement of the arterial pressure of a patient.
To measure this pressure by the palpation method, by the auscultative method or by the oscillometric method, one uses apparatuses which are called sphygmomano-meters.
The most recent methods are based always on the principal of the splyRmomanometry but have improved means to detect the pulsations or the arterial noises.
Among these methods~ the most used are the photoelectric pletis-mographie for the determination of the arterial pulsations and a system which amplifies the arterial noises.
Another detecting method for the arterial pulsations for the indirect measurement of the systolic and diastolic pressure is the use of ultrasonic waves.
The advantage of this method is its insensibility to the external noises and that it permits the measurement of the pressure even in the cases where the known methods which measure the arterial noises can not be used due to the low level of these noises (as it is the case by children or hypotensitives adults).
The method is based on the Doppler effect, the frenquency variation which is obtained is :
dF = 2f v/c where dF is the frequency of the incident ultrasonic waves v is the vibration speed of the arteria c is the propagation speed of the ultrasonic waves through the body tissues.
All these devices or methods to take the arterial pres-sure necessitate the use of a pneumatical inflatable bag which takes with it a non negligible manutention and thus a loss of time.
The aim of the present invention is to realize an auto-matic apparatus to measure the arterial pressure which does not use a pneumatical inflatable bag.
More specifically, the invention resides in an auto-matic apparatus for the measurement of arterial pressure, compri-sing a housing having a supple wall at one of its ends, said wall partly defining a measuring chamber within said housing, and in said housing a piezoelectric emitter of ultrasonic waves, a piezo-electric receiverof the Doppler effect, a piezoelectric pressure detector, said emitter and receiver and detector all being spaced from said wall, a measuring and display circuit electrically con-nected to said pressure detector to display pressure in said cham-ber, said receiver controlling said display circuit, whereby whensaid wall is applied against the artery of a patient, the ultra-sonic waves emitted by said piezoelectric emitter are reflected from said wall to said receiver and said display circuit displays the diastolic or systolic pressure of the artery to which said wall is applied, and means permitting a controlled leakage of air from said chamber.
The attached drawing shows schematically and by way of example one embodiment of the apparatus according to the invention.
Figure 1 is a schematic view of it.
!
~ 2 -, .
. .
10 70~3~6 Figure 2 shows at greatest scale the front portion of the apparatus.
Figure 3 is a block sheme of the apparatus.
Figure 4 shows electrical curves showing the working of the aparatus.
The apparatus comprises a casing 1 the wall 2 of which is constituated by a deformable supple material.
The front part of this casing comprises a measuring chamber 3 separated from the rest of the inside of the casing 1 by a wall 4. This wall 4 comprises a calibrated hole 5 as well as an aperture 6 the closing of which is controlled by a valve 7.
mis wall 4 carried further an ultrasonic waves transducer 8 the membrane of which separates the measuring chamber 3 from the rest 9 of the casing 1.
A support 10 placed within the chamber 3 and fixed to the casing 1, carries two ultrasonic waves transducers 11~ 12.
The transducer 11 is used as waves transducers transducer 12 is used as a detector for the ultrasonic waves which are reflected.
This support comprises a passageway 13 giving passage to the ultrasonic waves.
An emitter-receiver of ultrasonic waves 14, electrically connected to the transducers 11 and 12, emits at a power which is lower than 200 mW/cm2 in order to avoid the hemolyse effects which could be induced through the inter-mediary of the eransducer 11.
10708~L6 The transducer 8 is electrically connected to a measuring circuit controlling a display circuit 15.
This display appears however in 16 or 17 only when the presence of reflected ultrasonic waves is detected by the transducer 12. Finally a battery 19 delivers the electric power necessary to the working of the apparatusO
~ he resilient membrane 2 of the dome shown in full line in its rest position takes the position shown in dolted line when the operation of pressure measurement is in course, that is when this membrane 2 is applied against a member of the patient. The pressure inside the chamber 3 takes a maximum instantaneous value and diminishes slowly, due to the presence of the calibrated hole 5, the valve 7 being closed.
The transducer 11 emits an ultrasonic signal which is reflected in the presence of an arterial oscillation on the transducer 12. me two transducers 11, 12 are fixed on a support 10 which permits, through the apertures 13~ the penetration of the emitted ultrasonic waves up to the transducer 8 used as a pressure detector. This transducer 8 has its upper part in contact with the inside of the chamber 3 and its lower part in contact with the environemental aera When there is a pressure within the chamber 3, the upper part of the transducer is submitted to a mechanical stress which varies in function of the pressure~ At the end of 10708~L6 the measure and when the dome is taken away, the valve 7 is open and enables the wall 2 to take lts initial shape.
The membrane 2 of the dome deforms itself during the measurement of the pressure, and creates in the chamber 3 an instataneous pressure which is higher than the systolic pressures to be measured. This pressure diminishes slowly due to the hole 5 and corresponds successively to the diastolic and the systolic pressures to be measured.
Figure 3 shows an electrical diagram cf the system used. The emitter 20 is connected to the base of the emitting transducer 21; that base emits permanently on to the base of the transducer of the receiver 22 used as pressure detector The recelver 23 translates the pressure variations in electrical varlations. ~he base of the transducer for the reception 24 is submitted to the ultrasonic emission only in case of a vibration of the arteria In this case, the receiver 24 measures the Doppler signal obtained and actuates a memory 26 in coincidence with the first reception of the Doppler effect received. This blocks the displays 27, which receive permanently the pressure information which is inside the chamber 3, through the intermediary of the receiver 23. The maximum information is thus displayed in the first indicator 28.
During the second Doppler effect, the same cycle is reproduced, the me~ory 29 is selected and the minimum information is displayed in the-second indicator 30. The setting to zero is made by the switch 31.
10708~6 Figure 4 shows electric curves of the working of the system. Curve A shows the heart beats rythme (Ps being the systolic pressure and Pd the diastolic pressure The cure B shows the pressure within the dome before the measure and during the measure. The curve C shows the presence of Doppler effect signals in the receiver. These being defined in fuction of the pressure within the dome on the one hand and in function of the heart beat signal on the other side. The curves D and E determine the working moments thus the blocking of the displays.
When the pressure being in the chamber 3 is equal to the diastollc or systolic arterial pressure, the transducer 12 detects reflected ultrasonic waves modified by the beating of the artery. The signal which this transducer 12 delivers causes then the unlocking of the display circuit and the pressure being in the chamber 3, measured by this transducer 9~ is displayed to the indicating circuits 16~ 17 showing respectively the diastolic or systolic pressure.
The detection through Doppler effect of the beating of an artery is already used in medicine but only in combination with a pneumatic inflatable bag permitting to apply a pressure on the arm of the patient.
Used in combination with a pressure detector of the ultrasonic waves detector, which uses the same emitter 11~
this apparatus is self sufficient, and permits the direct digital reading of the arterial pressure. This apparatus is very easy and handy to use. It is to be noted that the pressure detector used is of the type of the one described in the Swiss Patent No. 598,587.
The sensibility of this apparatus enables to measure the arteri.al pressure of hypertensive individuals or o~ children.
. ,
To measure this pressure by the palpation method, by the auscultative method or by the oscillometric method, one uses apparatuses which are called sphygmomano-meters.
The most recent methods are based always on the principal of the splyRmomanometry but have improved means to detect the pulsations or the arterial noises.
Among these methods~ the most used are the photoelectric pletis-mographie for the determination of the arterial pulsations and a system which amplifies the arterial noises.
Another detecting method for the arterial pulsations for the indirect measurement of the systolic and diastolic pressure is the use of ultrasonic waves.
The advantage of this method is its insensibility to the external noises and that it permits the measurement of the pressure even in the cases where the known methods which measure the arterial noises can not be used due to the low level of these noises (as it is the case by children or hypotensitives adults).
The method is based on the Doppler effect, the frenquency variation which is obtained is :
dF = 2f v/c where dF is the frequency of the incident ultrasonic waves v is the vibration speed of the arteria c is the propagation speed of the ultrasonic waves through the body tissues.
All these devices or methods to take the arterial pres-sure necessitate the use of a pneumatical inflatable bag which takes with it a non negligible manutention and thus a loss of time.
The aim of the present invention is to realize an auto-matic apparatus to measure the arterial pressure which does not use a pneumatical inflatable bag.
More specifically, the invention resides in an auto-matic apparatus for the measurement of arterial pressure, compri-sing a housing having a supple wall at one of its ends, said wall partly defining a measuring chamber within said housing, and in said housing a piezoelectric emitter of ultrasonic waves, a piezo-electric receiverof the Doppler effect, a piezoelectric pressure detector, said emitter and receiver and detector all being spaced from said wall, a measuring and display circuit electrically con-nected to said pressure detector to display pressure in said cham-ber, said receiver controlling said display circuit, whereby whensaid wall is applied against the artery of a patient, the ultra-sonic waves emitted by said piezoelectric emitter are reflected from said wall to said receiver and said display circuit displays the diastolic or systolic pressure of the artery to which said wall is applied, and means permitting a controlled leakage of air from said chamber.
The attached drawing shows schematically and by way of example one embodiment of the apparatus according to the invention.
Figure 1 is a schematic view of it.
!
~ 2 -, .
. .
10 70~3~6 Figure 2 shows at greatest scale the front portion of the apparatus.
Figure 3 is a block sheme of the apparatus.
Figure 4 shows electrical curves showing the working of the aparatus.
The apparatus comprises a casing 1 the wall 2 of which is constituated by a deformable supple material.
The front part of this casing comprises a measuring chamber 3 separated from the rest of the inside of the casing 1 by a wall 4. This wall 4 comprises a calibrated hole 5 as well as an aperture 6 the closing of which is controlled by a valve 7.
mis wall 4 carried further an ultrasonic waves transducer 8 the membrane of which separates the measuring chamber 3 from the rest 9 of the casing 1.
A support 10 placed within the chamber 3 and fixed to the casing 1, carries two ultrasonic waves transducers 11~ 12.
The transducer 11 is used as waves transducers transducer 12 is used as a detector for the ultrasonic waves which are reflected.
This support comprises a passageway 13 giving passage to the ultrasonic waves.
An emitter-receiver of ultrasonic waves 14, electrically connected to the transducers 11 and 12, emits at a power which is lower than 200 mW/cm2 in order to avoid the hemolyse effects which could be induced through the inter-mediary of the eransducer 11.
10708~L6 The transducer 8 is electrically connected to a measuring circuit controlling a display circuit 15.
This display appears however in 16 or 17 only when the presence of reflected ultrasonic waves is detected by the transducer 12. Finally a battery 19 delivers the electric power necessary to the working of the apparatusO
~ he resilient membrane 2 of the dome shown in full line in its rest position takes the position shown in dolted line when the operation of pressure measurement is in course, that is when this membrane 2 is applied against a member of the patient. The pressure inside the chamber 3 takes a maximum instantaneous value and diminishes slowly, due to the presence of the calibrated hole 5, the valve 7 being closed.
The transducer 11 emits an ultrasonic signal which is reflected in the presence of an arterial oscillation on the transducer 12. me two transducers 11, 12 are fixed on a support 10 which permits, through the apertures 13~ the penetration of the emitted ultrasonic waves up to the transducer 8 used as a pressure detector. This transducer 8 has its upper part in contact with the inside of the chamber 3 and its lower part in contact with the environemental aera When there is a pressure within the chamber 3, the upper part of the transducer is submitted to a mechanical stress which varies in function of the pressure~ At the end of 10708~L6 the measure and when the dome is taken away, the valve 7 is open and enables the wall 2 to take lts initial shape.
The membrane 2 of the dome deforms itself during the measurement of the pressure, and creates in the chamber 3 an instataneous pressure which is higher than the systolic pressures to be measured. This pressure diminishes slowly due to the hole 5 and corresponds successively to the diastolic and the systolic pressures to be measured.
Figure 3 shows an electrical diagram cf the system used. The emitter 20 is connected to the base of the emitting transducer 21; that base emits permanently on to the base of the transducer of the receiver 22 used as pressure detector The recelver 23 translates the pressure variations in electrical varlations. ~he base of the transducer for the reception 24 is submitted to the ultrasonic emission only in case of a vibration of the arteria In this case, the receiver 24 measures the Doppler signal obtained and actuates a memory 26 in coincidence with the first reception of the Doppler effect received. This blocks the displays 27, which receive permanently the pressure information which is inside the chamber 3, through the intermediary of the receiver 23. The maximum information is thus displayed in the first indicator 28.
During the second Doppler effect, the same cycle is reproduced, the me~ory 29 is selected and the minimum information is displayed in the-second indicator 30. The setting to zero is made by the switch 31.
10708~6 Figure 4 shows electric curves of the working of the system. Curve A shows the heart beats rythme (Ps being the systolic pressure and Pd the diastolic pressure The cure B shows the pressure within the dome before the measure and during the measure. The curve C shows the presence of Doppler effect signals in the receiver. These being defined in fuction of the pressure within the dome on the one hand and in function of the heart beat signal on the other side. The curves D and E determine the working moments thus the blocking of the displays.
When the pressure being in the chamber 3 is equal to the diastollc or systolic arterial pressure, the transducer 12 detects reflected ultrasonic waves modified by the beating of the artery. The signal which this transducer 12 delivers causes then the unlocking of the display circuit and the pressure being in the chamber 3, measured by this transducer 9~ is displayed to the indicating circuits 16~ 17 showing respectively the diastolic or systolic pressure.
The detection through Doppler effect of the beating of an artery is already used in medicine but only in combination with a pneumatic inflatable bag permitting to apply a pressure on the arm of the patient.
Used in combination with a pressure detector of the ultrasonic waves detector, which uses the same emitter 11~
this apparatus is self sufficient, and permits the direct digital reading of the arterial pressure. This apparatus is very easy and handy to use. It is to be noted that the pressure detector used is of the type of the one described in the Swiss Patent No. 598,587.
The sensibility of this apparatus enables to measure the arteri.al pressure of hypertensive individuals or o~ children.
. ,
Claims (3)
1. Automatic apparatus for the measurement of arterial pressure, comprising a housing having a supple wall at one of its ends, said wall partly defining a measuring chamber within said housing, and in said housing a piezoelectric emitter of ultrasonic waves, a piezoelectric receiver of the Doppler effect, a piezo-electric pressure detector, said emitter and receiver and detector all being spaced from said wall, a measuring and display circuit electrically connected to said pressure detector to display pres-sure in said chamber, said receiver controlling said display cir-cuit, whereby when said wall is applied against the artery of a patient, the ultrasonic waves emitted by said piezoelectric emitter are reflected from said wall to said receiver and said display circuit displays the diastolic or systolic pressure of the artery to which said wall is applied, and means permitting a controlled leakage of air from said chamber.
2. Automatic apparatus as claimed in claim 1, and a further wall separating said housing into two portions one of which is said measuring chamber and the other of which contains said circuit, said emitter and detector being disposed in said measuring chamber, said pressure detector and said leakage means being carried by said further wall.
3. Automatic apparatus as claimed in claim 1, and a support within said chamber and fixed to said housing, said sup-port carrying said emitter and said receiver, said wall and said pressure detector being disposed on opposite sides of said support, and a passageway through said support that provides com-munication between said pressure detector and said wall.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH1168775A CH607746A5 (en) | 1975-09-09 | 1975-09-09 | Automatic apparatus for taking blood pressure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1070816A true CA1070816A (en) | 1980-01-29 |
Family
ID=4375890
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA260,786A Expired CA1070816A (en) | 1975-09-09 | 1976-09-08 | Apparatus for the automatic measurement of the arterial pressure of a patient |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPS5235488A (en) |
| CA (1) | CA1070816A (en) |
| CH (1) | CH607746A5 (en) |
| DE (1) | DE2640682A1 (en) |
| FR (1) | FR2323365A1 (en) |
| GB (1) | GB1562706A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56117432A (en) * | 1980-02-20 | 1981-09-14 | Nec Corp | Reception detecting circuit |
| JPS5741043A (en) * | 1980-08-25 | 1982-03-06 | Nec Corp | Frequency modulation radio receiver |
| FR2516781B1 (en) * | 1981-11-20 | 1986-05-30 | Cetehor | METHOD FOR THE RECORDING OF FETAL MOVEMENTS DURING PREGNANCY AND APPARATUS FOR IMPLEMENTING THE METHOD |
| JPH069616Y2 (en) * | 1989-02-28 | 1994-03-16 | 林電気株式会社 | Systolic blood pressure measuring device |
| US5094244A (en) * | 1989-08-25 | 1992-03-10 | Health Monitors, Inc. | Apparatus and process for determining systolic blood pressure, diastolic blood pressure, mean arterial blood pressure, pulse rate, pulse wave shape, respiratory pattern, and respiratory rate |
-
1975
- 1975-09-09 CH CH1168775A patent/CH607746A5/en not_active IP Right Cessation
-
1976
- 1976-09-02 GB GB3647776A patent/GB1562706A/en not_active Expired
- 1976-09-06 FR FR7626765A patent/FR2323365A1/en not_active Withdrawn
- 1976-09-08 CA CA260,786A patent/CA1070816A/en not_active Expired
- 1976-09-09 JP JP10838176A patent/JPS5235488A/en active Pending
- 1976-09-09 DE DE19762640682 patent/DE2640682A1/en not_active Withdrawn
Also Published As
| Publication number | Publication date |
|---|---|
| FR2323365A1 (en) | 1977-04-08 |
| GB1562706A (en) | 1980-03-12 |
| JPS5235488A (en) | 1977-03-18 |
| DE2640682A1 (en) | 1977-03-17 |
| CH607746A5 (en) | 1978-10-31 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |