The present invention relates to a vital-sign detection device for detecting vital signs such as blood pressure, ECG, bio-impedance or oxygen saturation. The vital-sign detection device includes a cuff on the inside of which a bladder made at least partly from a stretchable sheet material is provided to fit onto a body part such as a finger or toe or another limb, and at least one sensor to be placed onto the body part by means of the cuff.
Monitoring of physiological parameters such as blood pressure, oxygen saturation, heart rate, respiratory rate, temperature or ECGs has become an important part of modern health care. Traditionally, such physiological parameters have been measured by rather bulky and expensive instruments at a hospital or a medical doctor's office. In order to allow for a comfortable monitoring at home and during travel, or over long periods of times such as repeatedly measuring blood pressure at intervals over an entire day, small-sized, easy wearable detection devices have been developed to allow for comfortable, but still precise monitoring of relevant vital signs.
Such portable detection devices may include ring- or sleeve-shaped attachments that can be slipped or put on someone's finger to monitor at least one of the aforementioned vital signs or physiological parameters at the finger. In a similar way, such attachments may be put onto a toe, whereas other attachments can be put onto a wrist, an ankle or another limb of the human body, wherein it is also possible to attach the device to a body portion or a limb of an animal body.
Depending on the vital-sign parameter to be detected and the technology for detecting such parameter, the vital-sign detector may include at least one sensor that needs contact with the skin or the body part's surface, whereas sometimes it may be allowed to position the sensing component onto the fabric of a shirt's sleeve or more generally, over the fabric of clothing or a plastic, hygienic layer of rubber gloves, for example, covering the skin. Irrespective of the type of contact, i.e. direct or indirect contact, it is usually helpful to press the sensor against the body part's surface to assure full contact and close fitting of the sensor to the body part. For example, an inflatable bladder may be used for pressing the sensor against the limb's surface, wherein such bladders or balloons are basically known from blood pressure measuring devices including a cuff that can be wrapped around a patient's arm and adjusted to a size matching the patient's arm, wherein the bladder in the cuff may be pumped up so the bladder expands and the inside of the cuff is pressed against the arm's surface.
A blood pressure monitoring device configured as a ring to be slipped onto a finger of a patient and having an inflatable bladder is known from document WO 2018/140207 A1, wherein such known detection device includes a rigid cuff in terms of a plastic or metal ring which may be adjusted in size to fit different finger sizes. In one ring sector of the cuff, a tactile sensor array is arranged on the inside of the ring-shaped cuff, wherein an opposite sector of the cuff is provided with an inflatable bladder arranged on the inside of the cuff so as to expand towards the center of the ring, thereby press-fitting the tactile sensor array on the opposite side to the finger surface.
Depending on the rotatory position of the cuff on the finger, however, the signals provided by the sensing components may be weak. In particular, when unexperienced users or dithering fingers attach the cuff, the signal quality may be bad or no signal at all may be provided, as the sensor array may not be appropriately allocated to the artery running through the finger.
Furthermore, prior art document US 2011/0251470 A1 discloses a device for peripheral impedance plethysmography which includes a stretchable electrode. The stretchable electrode comprises an uninsulated stainless steel wire woven in the form of a tube that can be elongated, wherein the stretchable electrode is attached to a neoprene wrist band to be wrapped around an arm. Wrapping such neoprene wrist band around an arm or a leg of a human being works quite well, however, wrapping such wrist band around a finger is rather difficult due to the small size of a finger and the lack of space due to the neighboring fingers.
In view of the above, it is an object of the present invention to provide for an improved vital-sign detection device which avoids at least some of the aforementioned restrictions and disadvantages of the prior art and further develops the prior art in an advantageous manner. In particular, it is desired to provide for a vital-sign detection device which is easy to be mounted to a human body portion such as a limb, but nevertheless ensures reliable and sufficient contact to the limb's or body part's surface.
Furthermore, it is another objective of the present invention to provide for a vital-sign detection device allowing for cozy wearing and comfortable monitoring of the physiologic parameter even over longer terms.
A still further object may be precise detection of the relevant physiologic parameter even for unskilled, unexperienced users or elder people having dithering fingers.
A still further object is a miniaturized vital-sign detection device allowing precise monitoring of various vital parameters.
So as to achieve at least one of the aforementioned objectives, a vital-sign detection device is suggested which includes an electronic element fitted onto the body part by a bladder. More particularly, at least one sensor of the vital sign detection device includes an electronic element arranged on the stretchable sheet material of the bladder so as to be pressed onto the body part by deformation of the bladder.
Arranging the electronic element on the stretchable sheet material of the bladder allows for adaption of the electronic element to the body part contour and thus, full contact and close fitting of the electronic element to the body part surface. Furthermore, positioning of the electronic element is not restricted to a limited sector of the cuff left open by the bladder.
More particularly, due to positioning the electronic element on the bladder material, it becomes possible to choose different circumferential positions for the electronic element and/or more than one electronic element can be positioned at various positions since the electronic element position is no longer restricted to a ring sector not covered by the bladder as is the case with the prior art. Due to such freedom in positioning the electronic element, it becomes easier to bring the electronic element into a position allowing the sensor to receive good signals from the body part to which the device is attached.
So as to make the cuff closely fit onto the respective body part, an interior space of the bladder may be filled with, for example, pressurized air or gas, or a pressurized fluid to pump up the bladder. When the interior space of the bladder expands due to the inflow of air, gas and/or fluid, the stretchable sheet material is deformed to snuggly fit onto the contour of the body part. At the same time, the electronic element gets into well-set or close fitting contact to the body part.
According to an advantageous aspect, at least a portion of the electronic element may be stretchable. More particularly, the electronic element may include a stretchable portion which is arranged on and/or in the stretchable material of the bladder, wherein it is also possible that the entire electronic element is stretchable.
When the electronic element itself is stretchable or deformable, it may compensate the deformation of the bladder and the changes in shape thereof.
Thus, the bladder may not only effect close fit of the cuff and the sensor onto the body part, but at the same time the bladder may be part of the electronic element(s) of the sensor and vice versa. More particularly, the electronic element may be sort of integrated into the bladder. Such electronic element may basically include various electronics such as a wiring or electrode which is usually formed on a printed circuit board and various electronic components or connections therebetween. For example, the electronic element may include photodiodes, LEDs, piezo elements, capacitors, microchips or other electronic components useful for sensing vital signs.
Generally, the electronic element may include at least one sensing component that senses the parameter or vital sign of interest and provides a signal representing a characteristic thereof. Depending on the vital sign to be detected, different types of sensing components may be provided, wherein such different types of sensing components may be provided at the same time to allow the vital-sign detection device to detect different physiologic parameters and vital signs.
The at least one sensing component may be stretchable or may at least include a stretchable portion which may be arranged on the stretchable material of the bladder. However, in the alternative, the sensing component does not have to be stretchable.
For example, the sensing component may include one or more photodiodes cooperating with one or more LEDs or more generally, one or more light sensors cooperating with one or more light sources so as to allow, for example, plethysmograms and/or the determination of blood pressure and/or the determination of oxygen saturation and hemoglobin levels. In addition or in the alternative, the sensing component may include other types of sensing elements such as one or more pressure sensing components and/or one or more temperature sensing components and/or one or more magnetic field generators cooperating with one or more magnetic field sensors and/or one or more piezo based transmitters and receivers.
Basically, the sensing component could be arranged directly on either side of the electronic element what allows easy connection in terms of short wirings and signal transmission. For example, an array of sensor elements may be provided onto the electronic element to measure the body part's impedance.
In addition or in the alternative, at least one sensing component may be positioned separate and/or spaced apart from the electronic element, wherein according to a further aspect of the present disclosure the sensing component may be positioned on the stretchable sheet material of the bladder with circuitry connecting the sensing component to the electronic element being provided on and/or in the stretchable sheet material of the bladder. Positioning the sensing component spaced apart from the electronic element on the stretchable sheet material of the bladder allows for choosing the appropriate position for the sensing component irrespective of the position of the electronic element. For example, a photo sensor component such as a photodiode cooperating with a light source such as an LED may be arranged on bladder portions substantially opposite to each other, whereas the electronic element may be positioned on another portion of the bladder which may be positioned in between the bladder portion supporting the sensing components.
According to a further aspect, the electronic element and the at least one sensing component may be positioned on opposite sides of the stretchable sheet material of the bladder. More particularly, the electronic element may be positioned on the exterior or skin contact side of the stretchable sheet material of the bladder (which may form the inner side of the ring-shaped device to be attached onto the finger), whereas the at least one sensing component may be positioned on the interior or radially outer side of the stretchable sheet material of the bladder (which may form the interior wall side facing the expandable volume chamber of the bladder). Such arrangement of the sensing component in the inner chamber of the bladder or on the interior side of the stretchable sheet material of the bladder shelters efficiently uses the available space, thereby rendering the device very compact in size.
So as to connect the sensing component on one side of the stretchable sheet material to the electronic element on the other side of the bladder's stretchable sheet material, the circuitry may go through this stretchable material from one side to the other side. For example, the connecting circuitry may include some vias going through the stretchable sheet so as to connect the sensing component to the electronic element on opposite sides thereof. The conductive material of such vias may be embedded in the stretchable sheet material of the bladder at least partially. More particularly, the vias may penetrate the stretchable sheet material in a sealed manner to allow pressurizing and inflating the bladder by means of pressurized air, pressurized gas and/or pressurized fluids and/or pressurized liquids.
In addition or in the alternative to circuitry going through the stretchable sheet material of the bladder from one side to the other side thereof, it is also possible to connect the sensing component arranged on one side of the sheet material to the electronic element positioned on the other side of the material by means of circuitry extending along opposite sides or opposite surfaces of the sheet material to a portion of the bladder where the sheet material overlaps and/or a portion of the stretchable sheet material projecting from the inflatable portion of the bladder.
More particularly, like the strap of a wrist watch, the stretchable sheet material of the bladder may form a loop with end portions of the strip-like sheet material overlapping each other. At such overlapping section, the interior side of one end portion of the sheet material may face the exterior side of the other end portion of the sheet material, thus allowing to contact circuitry on the interior side to circuitry on the exterior side. Thus, the sensing component on the interior side of the stretchable sheet material may be connected to the electronic element on the exterior side of the stretchable sheet material without penetrating or perforating the stretchable sheet material.
For example, electronic elements on an interior side of the stretchable sheet material may extend to one end portion thereof, whereas electronic elements on the opposite side of the stretchable sheet material may extend to the other end portion thereof so, when forming the sheet-like material into a loop-like configuration, the electronic elements may contact each other at the end portions overlapping each other.
In addition or in the alternative of connecting the circuits on the opposite sides to each other at such overlapping loop portion, the circuits also may extend to a common end portion extending beyond and/or projecting from the bladder portion or loop portion so the circuits may be connected at such common end portion outside the bladder where the stretchable material is not subject to expansion.
At an outer side of the bladder, the cuff may include an outer ring element made from a non-stretchable material, for example a fiber reinforced plastic material or fabric or made from a rigid plastic and/or metal material. Despite being non-stretchable, the material may flex or bend but not expand or contract as it is the case with a sheet of paper or a fiberglass strip. In the alternative, a rigid material like metal may form such outer ring element.
Such non-stretchable outer ring element may support the bladder at an outer peripheral side and/or against radial expansion and/or radial deflection so the bladder may apply the desired pressure onto the body part on which the ring-shaped device is positioned. The bladder may extend along the entire inner side of the outer ring element to form a 360° inner ring element. It is preferable since the pressure then presses the stretchable sheet material to the whole circumference of the body part and more accurate measurement or detection of the vital-sign can be achieved. However, this is not necessary, but the bladder may cover only a portion of the inner surface of the outer ring element and/or extend along less than 360° such as for example 270°.
The outer ring element made from non-stretchable material may form a substantially flat ring having a substantially rectangular or flattened cross-section. The bladder may form a ring-shaped tube the outer side of which may contact the inner side of the outer ring.
However, in the alternative, the outer ring element made from non-stretchable material may have a substantially U-shaped cross-section and/or may have a concave inner ring side contour forming a sort of chute or channel extending along the inner side of the outer ring element. When using the aforementioned tube-like bladder, the outer side of the bladder may nestle into such concave inner ring side to give support not only in the radial direction but also in the axial direction to some extent.
However, according to a further aspect, the bladder does not need to have a tube-like configuration. More particularly, the stretchable sheet material of the bladder does not need to have a tube-like configuration with a ring-shaped cross-section, but the stretchable sheet material of the bladder may form an inner shell cooperating with the outer ring element made from non-stretchable material forming the outer shell. The stretchable sheet material forming the inner shell may be connected to or fixed to the outer ring element along side edges of the strip-like, stretchable sheet material.
More particularly, the outer ring element may have a substantially U-shaped cross-section or a concave, chute-like inner ring side with a pair of webs or flange-like rims extending towards the center of the ring-shaped device and/or substantially radially inwards. The stretchable sheet-material of the bladder may be fixed to the webs or rims of the non-stretchable outer ring element so the expandable volume of the bladder may be defined in part by the stretchable sheet material and in part by the non-stretchable outer ring element. Due to the inwardly extending side rims of the outer ring element, a chamber is formed even when the stretchable sheet material is not bulging or otherwise expanded or substantially flat, thereby giving space for accommodating the aforementioned sensing components such as LEDs, photodiodes, pressure sensing elements or other sensing components.
Furthermore, due to the inwardly extending side rims of the substantially rigid outer ring element, a dead space left between the stretchable sheet material and the outer ring body which facilitates uniform inflation of the bladder along the circumference of the body part and in particular over the full circumference of a finger when the bladder forms a closed 360° ring.
In the alternative, it also would be possible to attach the stretchable sheet material with some slack or some excess in material to a substantially flat outer ring element so the stretchable material, already in its non-expanded state, may form a substantially U-shaped cross-section to define a dead space between the outer ring element and the bulging stretchable sheet material.
So as to expand the bladder to achieve pressure onto the body part surface, the detection device may include a pump for pumping pressurized gas or air into the inner bladder chamber, wherein such pump may be positioned outside the inner bladder chamber and more particularly, on an outer side of the outer ring element made from non-stretchable material. For example, the pump may be arranged on the outer circumferential side of the outer ring element, wherein a pressurizing gas channel communicating the pump with the inner bladder chamber may extend through the outer ring element.
The pump may include a micro-blower. Such micro-blower may supply sufficient air flow and pressure and achieves a very compact design. The micro-blower may be integrated into the outer ring element of the cuff.
The signals and/or values collected by the sensing component and/or the electronic element may be processed and/or analyzed in different ways and/or at different locations. For example, the portable device itself may include a signal processor and/or a data analysis unit so as to determine the desired vital sign and/or physiologic parameter from the sensing signals. The signal analysis unit may be integrated into the cuff device. Furthermore, a display unit may be provided at the wearable device to display the relevant information relating to the desired vital sign. For example, similar to traffic lights, there may be red, green and yellow lights in terms of LEDs for example, to indicate the determined vital signs are okay, not okay or still okay, but close to not okay. In addition or in the alternative, more sophisticated display units may be provided such as a display screen indicating precise values of the respective vital sign such as blood pressure values or oxygen saturation values. Other display units such as acoustic output may be provided.
In addition or in the alternative to such data analysis and/or information display at the cuff device itself, the signals collected by the sensing component and/or partially preprocessed signals may be transmitted to an external analysis and/or display system which may include, for example, a data server or a computing unit at a hospital or a doctor's office. So as to allow for such data and/or signal transmission, the detection device to be attached to a body part may include a data transmission component which may include a wired transmitter, a Bluetooth transmitter, a radio transmitter and/or other mobile data communication components. Such data transmission device may be incorporated into the ring-shaped cuff or, in the alternative or in addition, a data transmission component may be releasably connected to the cuff or another element of the detection device which may include a data interface.
Further details and optional embodiments of the invention will become apparent from the following description of examples of the invention and the drawings corresponding thereto. In the drawings show:
As can be seen from
The cuff 2 including the bladder 3 on the inside thereof, however, also may be configured to snuggly fit onto other limbs such as a toe, the wrist of an arm or the ankle of a leg or other body portions at which a vital sign can be measured. Due to the cuff having a deformable bladder on the inside, the detection device may be miniaturized to fit onto small body portions such as a small finger, and also allows an invasive use, wherein, for example, the cuff may be mounted around an artery.
The cuff 2 may include an outer ring element 4 which may be made from a non-stretchable material such as a fiber reinforced plastic material or a rigid plastic and/or metal material.
Along the inner circumferential side of the ring element 4, the bladder 3 is provided which itself may form a closed ring in terms of a 360° ring covering substantially the entire inner peripheral surface of the outer ring element 4. However, as mentioned before, the bladder 3 may extend along only a portion of the inner peripheral side and may have a C-shape or extend, for example, along about 180° to 270° or another portion of a circle.
The bladder 3 may have a tubular configuration with a radially outer side contacting the inner peripheral side of the outer ring element 4. The tubular bladder 3 may define an interior inflation chamber or bladder chamber which may be filled with air or a gas or another fluid or liquid so as to expand the bladder 3.
The bladder 3 may be formed from a stretchable sheet material 5 which may form the aforementioned tube having a closed, substantially ring-shaped cross-section.
Advantageously, the stretchable sheet material may be an elastic material which is elastically deformable. For example, the stretchable sheet material may be rubber or a rubber-like plastic material.
As it is shown by
The outer crosswise extending portion 7 may form the outer peripheral side of the ring element 4.
On the other hand, the stretchable sheet material 5 bridges the distance between the rims 6 and forms the inner peripheral side of the cuff 2. Due to the U-shaped cross-section of the outer ring element 4, a dead space is defined between the stretchable sheet material 5 and the outer crosswise extending portion 7, the dead space forming the interior bladder chamber 8 into which pressurized air or gas may be supplied to inflate or expand the bladder 3, more particularly, the stretchable sheet material 5 may bow or bulge or belly inwardly towards the center of the ring when the interior chamber 8 of the bladder 3 is filled with pressurized gas, air or liquid.
As can be seen from
As can be seen from
So as to inflate and expand the bladder 3, a pump 10 may be provided which may be a micro blower. The pump 10 may be arranged at and/or attached to the outer peripheral side of the cuff 2, wherein a communication channel 11 may extend through the outer ring element 4 to fill air or gas into the interior bladder chamber 8, cf.
The pump 10 may be controlled by a control unit 12 which may include electronics such as a processing unit and a storage, wherein such control unit 12 may be part of the detection device 1.
So as to detect relevant vital signs such as blood pressure, oxygen saturation or ECG, at least one sensor 13 may be provided so as to placed onto the finger or another body part of the human body by means of the cuff 2.
More particularly, the sensor 13 may include at least one electronic element 14 which is positioned on the stretchable sheet material 5 of the bladder 3. More particularly, the electronic element 14 may be positioned on and/or fixed to the inner peripheral side of the bladder 3 which is formed by the exterior surface of the stretchable sheet material 5, i.e. the surface of the sheet material 5 facing away from the interior chamber 8 and towards the center of the ring. Due to its position on the inner side of the stretchable sheet material 5, the electronic element 14 achieves good electric contact to the anatomical surface of the body part. The electronic element 14 may fully contact the surface of the body part and snuggly fit onto the contour thereof.
The electronic element 14 may include a tactile sensor array formed from, for example, a plurality of individual capacitive sensors, and/or an array of different type of sensors forming such sensor array. More generally, the electronic element 14 may include integrated circuits which are usually formed in a printed circuit board, electronic components or other elements, wherein the electronic element 14 may be part of the bladder 3 in terms of taking part in deformations of the bladder and compensating changes in shapes thereof.
Irrespective of the sensor function of the electronic element 14, the sensor 13 may further include sensing components 15 positioned spaced-apart and/or separate from the electronic element 14. Such sensing components 15 may include a photodiode and a light source such as an LED 16 cooperating therewith, wherein other sensing components such as temperature detectors or pressure detectors may be provided.
As can be seen from
To allow the sensing components 15 visual contact to the body part, the stretchable sheet material 5 may be transparent for the transmitter and sensing elements. In addition or in the alternative, the stretchable sheet material 5 may include a transparent window portion through which the transmitting and sensing components 15 may look onto the body part.
So as to electrically connect the sensing components 15 to the electronic element 14 and/or to allow signal transmission between the sensing components 15 and the electronic element 14, circuitry may be provided on and/or in the stretchable sheet material 5. For example, the circuitry may include vias penetrating the sheet material 5 and connecting the sensors 15 on the one side of the sheet material 5 to the electronic element 14 on the other side thereof.
In addition or in the alternative to such vias penetrating the sheet material 5, the circuitry may include conductive circuits 17 and/or electronic elements and/or transmitting elements extending along the outer side of the stretchable sheet material on the one hand and along the inner side thereof on the other hand, wherein such circuit 17 may extend to opposite end portions 5a and 5b of the stretchable sheet material 5, as can be seen from
When forming a loop with the stretchable sheet material 5 so that the end portions 5a and 5b overlap each other, cf.
Another example of connecting electronic components on one side of the stretchable sheet material 5 and the electronic element 14 on the other side of the stretchable sheet material 5 without perforating the stretchable sheet material 5 is shown by
As can be seen from
Furthermore, the processor 25 may communicate with a driver 20 for driving and operating the pump 10 to expand the bladder 3.
The processor 25 may analyze the signals of the sensing component to determine the desired physiologic parameters or vital signs and/or may transmit the signals and/or the analyzed information to other data processing units 21 such as servers and computers at a hospital, a doctor's office or a home. As can be seen from
As can be further seen from
Number | Date | Country | Kind |
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21160245.3 | Mar 2021 | EP | regional |
The present application is a continuation of International application No. PCT/EP2022/051256, filed Jan. 20, 2022, which claims priority to European Patent Application No. 21160245.3, filed Mar. 2, 2021, the entire contents of each of which are incorporated herein by reference.
Number | Date | Country | |
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Parent | PCT/EP22/51256 | Jan 2022 | US |
Child | 18455785 | US |