RU2251386C2 - Device for automatic measurement of blood pressure - Google Patents

Abstract

FIELD: medicinal equipment.

SUBSTANCE: the present innovation deals with devices for measuring patient's blood pressure. The suggested device contains inflatable gasket designed with possibility to be fixed around patient's shoulder or wrist. The device is supplied with either electric or electronic pressure pickup unit and is being a manual device containing a bulb indicated for inflating a gasket and a body which, in its turn contains a unit to control and depict information. Blood pressure is automatically detected based upon oscillometric technique. The suggested device enables to simply and accurately measure patient's blood pressure, moreover, it has got low power supply, provides better comfort for a patient to measure blood pressure and provides increased reliability of the device to control blood pressure.

EFFECT: higher efficiency of blood pressure measurement.

6 cl, 3 dwg

Description

FIELD OF THE INVENTION

The present invention relates to a device for measuring blood pressure of a patient.

State of the art

A known method of measuring the blood pressure of a patient, in which an inflatable cuff is located around the shoulder of the patient. The cuff pressure is displayed on a mechanical or mercury pressure gauge. A stethoscope is located between the patient’s shoulder and the inflated cuff. The pressure values shown by the pressure gauge when Korotkov sounds appear and disappears during the release of air from the cuff are systolic and diastolic blood pressure values. Doctors highly appreciate this method of measuring blood pressure due to its relatively high accuracy, which is achieved by simple means and because of the possibility of additional diagnostic steps when using a stethoscope.

Fully electronic methods for measuring blood pressure are also known, for example, based on the oscillometric method. Depending on the pressure inside the cuff, measured according to some algorithm, systolic and diastolic blood pressure values are calculated and displayed on a digital display.

Such automatic blood pressure monitoring devices typically include an electric pump for pumping air into the cuff. Such pumps have several drawbacks: the operation of an electric pump leads to high energy consumption. Thus, frequent battery changes become necessary. In addition, the rate of air injection is limited by the power of the electric pump. And that means you can’t pump up air faster if necessary for some patients. In addition to the above, some patients are afraid of automatic air injection.

Also known are the so-called semi-automatic devices for monitoring blood pressure, which are equipped with a bulb for manually pumping the cuff. The pear connects to the cuff using a tube. These well-known devices also have some drawbacks: using three separate devices (cuff / pear / measuring unit and displaying the results) is not very convenient.

The proper use of such devices can be difficult and especially for older and disabled people. The tubes needed to connect the information display unit and the cuff and the connection of the pear and cuff make these blood pressure monitoring devices more vulnerable to mechanical damage. Moreover, for this type of device, a table or some other surface is always required in order to place an information display unit on it during measurements. This feature is a big disadvantage, especially when used in a hospital, where it is common to use the device when moving or use the device directly on the patient’s bed.

SUMMARY OF THE INVENTION

The aim of the present invention is to overcome the disadvantages of existing devices and more specifically: to provide a device for automatic measurement of blood pressure, which allows simple and accurate measurement of blood pressure values, while this device should have a relatively low power consumption and be easy to use. Another objective of the present invention is to improve the convenience of the patient and increase the reliability of the device for monitoring blood pressure.

These and other objectives are achieved in accordance with the present invention using a device for measuring blood pressure, which corresponds to the distinctive part of the independent claim.

The blood pressure measuring device of the present invention is used to measure the blood pressure of a patient, for example, on the shoulder, using an oscillometric method. The device includes an inflatable cuff, which is located around the wrist or shoulder of the patient. In addition, the device for measuring blood pressure contains a control unit and display information that is connected or can be connected to the cuff using a tube.

The control and information display unit is equipped with at least one electric or electronic pressure sensor for measuring pressure inside the cuff. In addition, the control and information display unit includes a digital display and a calculation unit. The calculation unit is programmed to calculate systolic and diastolic blood pressure values based on cuff pressure pulsations, which are measured by the sensor. The calculations are carried out in a known manner, for example, by means of the oscillometric method.

In accordance with the present invention, the control and information display unit is provided with a bulb for manually pumping air into the cuff.

The pear is attached directly to the housing containing the control unit and display information. According to the invention, a hand-made device for monitoring blood pressure, which automatically determines the values of blood pressure using the oscillometric method, and a hand-held pear for pumping are proposed in one piece. The pear is mounted in a housing containing a control unit and display information. Therefore, the body can simply be held with one hand, while the pear can be pressed with the fingers of the same hand.

It is advisable that the housing contains a pressure sensor, a calculation unit, pressure control valves, a display and a bulb for pumping. Pressure control valves include an exhaust valve to reduce pressure during the measurement and a valve to relieve pressure after the measurement. Both valves can be either mechanical or automatic / electrical. Essentially, a device for monitoring blood pressure consists of two parts: a body with a control unit and display information and cuffs that are connected to each other with only one tube.

If an automatic exhaust valve is used, it can also be used as a pressure relief valve. During measurements, this valve slowly relieves the pressure in the cuff and acts as an exhaust valve. After taking measurements, the valve quickly reduces pressure and acts as a pressure relief valve.

The blood pressure monitoring device of this invention has several advantages. Since the device consists of only two parts, it is easy to work with and there is no need for an electric pump. Power consumption is significantly reduced, and batteries can last for quite a while. In addition, those who use the device can choose the inflation speed of the cuff as they wish.

It is advisable to equip the calculation unit with a switch. The switch can be set to the “on” position when the pear is first compressed. As soon as the user of the device starts to inflate the cuff, the switch is turned to the “on” position and the calculation unit is turned on. This device can also be equipped with a timer that would turn off the calculation unit after a certain period of time. Thus, it is possible to make a device for monitoring blood pressure without an external switch. This design simplifies the use of the device, since the user does not have to turn on the device before starting measurements. In addition, the device will be cheaper in production, because it is possible to do without additional manual switches. Automatic shutdown will help to conserve battery power.

In addition, with a preferred implementation of the device, the calculation unit is programmed to display the moment when the cuff pressure has reached the desired set value. This moment will show the user when he can stop pumping the cuff. You can also show that the pressure in the cuff has not yet reached the set value and it is necessary to continue pumping air. Further, it is possible to make the measurement of blood pressure begin automatically as soon as the set pressure value in the cuff is reached and the pressure begins to decrease. Measurement cannot begin while the pump is running, as the pressure will continue to increase.

The control unit and the information display can be equipped with an automatic valve for depressurizing, designed to automatically depressurize the cuff after measurements, that is, after determining the value of diastolic blood pressure. This property, on the one hand, provides great convenience for the person who takes measurements, but, on the other hand, at least one “off” button is required in order to manually initiate a valve to relieve pressure if the patient is uncomfortable if the cuff is still under pressure.

Further, the device can be equipped with an active controllable exhaust valve, which has the following advantage: the calculation unit can control it, while the optimal pressure reduction rate can be selected for each specific condition (for example, high or low heart rate).

In another implementation, the exhaust valve is a passive, self-adjusting valve. Similar valves are known. The valve operates in such a way that the pressure reduction inside the cuff is constantly within two to five millimeters of mercury (mmHg) per second, regardless of the pressure inside the cuff. Such a valve may remain open during inflation of the cuff, since the inflation rate is much greater than the rate of pressure reduction. Such a valve can be equipped with a button, when pressed, the pressure is quickly released. This allows you to achieve the most user-friendly design of a device for measuring blood pressure while at the same time very low cost of materials. To take the measurement, the user only needs to manually inflate the cuff with the pear. As soon as the required pressure value is reached, the user can stop pumping the cuff and the blood pressure measurement will continue to be carried out in fully automatic mode. After determining the diastolic pressure, the user can simply press the valve button to relieve the remaining cuff pressure.

The inflating bulb and manual exhaust valve, if any, are made so that they can be activated with one hand. This design will be ergonomic, as it allows the user to fully measure with one hand, while the other hand remains free.

The calculation unit may, in addition to the above, be programmed to calculate the pulse rate of the patient and to control the rate of decrease in pressure exerted by the exhaust valve.

This invention can be better understood with the help of explanatory drawings, which depict the following:

Figure 1 is a schematic illustration of a device for measuring blood pressure in accordance with this invention.

Figure 2 - image of a pear built into the device for measuring blood pressure.

Figure 3 - bitmap image of a device for measuring blood pressure, this figure shows the individual elements of the device.

Information confirming the possibility of carrying out the invention

A blood pressure measuring device 1 according to the invention is shown schematically in FIG. The device 1 includes a cuff 2 and a control unit and display information 3.

The cuff 2 is designed to be fastened around the wrist or shoulder of the patient.

The information control and display unit 3 is connected to the inflatable cuff 2 by means of a tube 4. The information control and display unit 3 includes a pressure sensor (not shown) for measuring pressure P inside the cuff. The information control and display unit 3 is mounted in a housing 9 made of plastic.

The device 1, in addition, is equipped with a bulb 8 for manually pumping the cuff 2 and, optionally, a composite valve 11 to reduce pressure during measurements and manually relieve pressure in the cuff 2 after measurements. The pear 8 is attached to the body so that it is possible with one hand to hold the body and squeeze the pear.

Based on the electrical signal generated by the electric or electronic pressure transducer, the blood pressure value is calculated using the oscillometric method.

The calculations are performed in the block of calculations 7, which is built into the block 3 of the control and display information. Computing unit 7 is a microprocessor, for example, one of the 3822 series of Mitsubishi. The signal of the pressure sensor falls into the calculation unit 7. The measurement of blood pressure is as follows. In one embodiment of the invention, a device for monitoring blood pressure is provided with an automatic on function. When the user first presses the pear 8 for pumping, the calculation unit 7 is turned on.

The microprocessor can in standby mode constantly check the pressure indicated by the sensor and turn on the display (and close the automatic valve to relieve pressure where applicable) after reaching a predetermined pressure, for example, above 20 mmHg. Another way, more energy-efficient is the way to include in the design of an additional pressure-sensitive microswitch.

If there is no such automatic turn-on function, then the device can be turned on manually before the user starts pumping, similar to what is done in the known manual pressure measuring devices.

Then the cuff is inflated to a certain pressure P by compressing the pear 8. The pressure P is, for example, 40 mm Hg. higher than presumed systolic blood pressure of the patient. If the pressure P in the inflated cuff is too low, the algorithm will determine this situation and display on the display that it is necessary to further inflate the cuff to a higher value. After inflation of the cuff, the pressure in the cuff 2 gradually decreases and the pressure values in the cuff 2 are measured.

In the first implementation, the pressure is automatically reduced using a passive, self-regulating valve 11. During the pressure reduction process, the pressure value P in the cuff 2 is constantly measured using the pressure sensor and calculation unit 7. After depressurizing the cuff, in the calculation block using the oscillometric method, values of systolic and diastolic blood pressure. The oscillometric method for determining blood pressure is known per se.

Based on the pressure measurements during the pressure reduction process, it is also possible to determine the pulse rate of the patient. To determine the heart rate in the calculation unit 7, the time difference between the maxima and / or minima of the pressure in the cuff 2 is determined. After the pressure relief process is completed, the digital display 6 displays the blood pressure and sometimes the heart rate.

In a subsequent implementation, instead of a passive valve to reduce pressure, an automatic exhaust valve, such as a solenoid valve, is mounted. In this case, the calculation unit controls the rate of pressure decrease.

After completing the measurement cycle (which ends with the display of blood pressure values and, sometimes, pulse rate and discharge of the pressure remaining in the cuff), the device for monitoring blood pressure automatically turns off if it is not used for a certain period of time, for example, after five minutes, except when there is a power button and it is not pressed after measurements.

Figure 2 shows a bit-wise image of some implementation of the block 3 corresponding to the invention.

The housing 9 of the device 1 for measuring blood pressure consists of a lower cover 32 and an upper cover 31. The lower and upper covers 32, 31 are made of plastic, for example, are made using injection molding. The top cover 31 is provided with a casing 34. The pear 8 is partially closed by a casing 34, which serves as a support for the pear 8. The pear 8 is attached to the top cover 31 using the pear holder 33. The information control and display unit 3 is made essentially between the pear 8, the upper a lid 31 and a lower lid 32, is connected to the cuff using a tube 4. Pear 8 is equipped with a manual valve 11, designed to quickly relieve pressure in the cuff. Pear 8 contains an automatic or passive valve 11 to reduce the pressure in the cuff during measurements and a check valve 10 for air inlet into the pear. A conventional pressure sensor 5, a printed circuit board 30 with a microprocessor, and a digital display 6 are located in the housing 9, which is formed by the upper and lower covers 31, 32. These parts are known to qualified specialists in this field. Additional parts for fastening elements, electrical connections, turning on and off, known to those skilled in the art, are also shown in FIG. 2.

The casing 34 contains an opening 35, which is the hole through which the check valve 11 is inserted. This helps to further fix the bulb 8 in the housing 34. To pump the cuff, the blood pressure measuring device can be held by the hood 34 with one hand. The bulb 8 can be pressed with the fingers of the same hand .

The measured blood pressure values are displayed on a digital display 6, which the user can look through the hole closed by glass 36 in the upper cover 31 of the housing 9. To quickly relieve pressure, the user can open the valve to release pressure 11 with the finger of the same hand.

Figure 3 shows a schematic illustration of a device 1 for measuring blood pressure. Here and in figure 1, the same numbers indicate the same parts of the device.

The pressure P in the cuff 2 is measured by an electronic or electric pressure sensor 5.

The pressure P in the cuff 2 is increased by means of the bulb 8 and can be reduced by means of the valve 11.

The electrical signal that the pressure sensor 5 generates is supplied to the oscillometric circuit 15. The pressure 5 is determined in the oscillometric circuit 15 based on the electrical signal. The output of the oscillometric circuit 15 is supplied to the microprocessor 7. The systolic and diastolic blood pressure values are calculated by the microprocessor 7 and displayed on the display 6. The device is powered by a battery 13 connected to the microprocessor 7, through a power amplifier 16, with a voltage regulator 17 and with an oscillometric circuit 15. The device is also equipped with a potentiometer 18 connected to a power amplifier 17 and a microprocessor 7.

In addition, there is an oscillator 19 necessary for the operation of the microprocessor 7. The microprocessor 7 determines, using the oscillometric method, the values of blood pressure based on pressure R.

Elements used in device 1 are known to those skilled in the art.

Claims (7)

1. A device for automatically measuring the blood pressure of a patient, comprising an inflatable cuff configured to be mounted around the patient’s shoulder or wrist, a housing comprising a control and information display unit that is configured to connect to the cuff using a tube, the control unit and the information display contains at least one electric or electronic pressure sensor for measuring pressure inside the cuff, a calculation unit for calculating using the oscillometric method, the values of blood pressure based on the pressure inside the cuff, and the associated display, characterized in that it is equipped with a bulb for manually pumping the cuff, while the bulb is connected to the body so that the patient can hold the body with one hand and squeezing pears. 2. The device according to claim 1, characterized in that the calculation unit is equipped with an on / off switch, configured to be switched on during the first compression of the bulb for manual pumping. 3. The device according to claim 1 or 2, characterized in that the control unit and information display includes a passive self-regulating exhaust valve. 4. The device according to any one of claims 1 to 3, characterized in that the calculation unit is programmed with the ability to display the pressure in the cuff, which has reached the required set value, or display the pressure in the cuff, which has not yet reached this set value. 5. The device according to claim 1 or 2, characterized in that it includes a manual or automatic valve to relieve pressure. 6. The device according to claim 5, characterized in that the pear for manual inflation and the manual valve for relieving pressure are made with the possibility of controlling them with one hand. 7. The device according to any one of claims 1 to 6, characterized in that the calculation unit is programmed with the ability to calculate the pulse rate of the patient and control the rate of release of air from the valve.

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