JP6603836B1 - Blood leak detection device - Google Patents

Abstract

The blood leak detection device of the present invention includes a light source, a light receiving element, and a control means connected to the light source, and the light source covers the lower surface of a cloth-like blood leak receiving member disposed below the blood leak location. The light receiving element is disposed at a position to illuminate, and the light receiving element is disposed at a position capable of receiving the reflected light emitted from the light source and reflected by the lower surface of the blood leakage receiving member. The control means includes a light receiving intensity of the reflected light at a predetermined first wavelength within a range of red light having a wavelength of 620 nm or more and 750 nm or less, which is a light reflection band of blood, among wavelengths of reflected light received by the light receiving element. , And the received light intensity of the reflected light at one or more other wavelengths less than 620 nm. Thereby, it can be detected from the back side of the drape whether the liquid adhering on the drape is blood. As a result, there are few malfunctions due to liquids other than blood.

Description

  The present invention relates to a blood leak detection apparatus that monitors whether or not blood leaks from a living body at a puncture site, a suture site, a drain site, or the like.

  For example, in an artificial kidney (dialyzer), an accident may occur in which blood leaks due to the indwelling needle on the side that returns blood passed through the artificial kidney to the patient. If such an accident is left unattended, it will endanger the dialysis patient's life due to blood loss.

  Also, even if it is not a large amount, a small amount of blood that does not affect life or treatment leaks from the indwelling needle and its surroundings during dialysis treatment, and the arm of the dialysis patient and the sheets laid under the arm, etc. Impermeable woven fabric, or impervious puncture or puncture sheet placed and placed in advance under the arm of a dialysis patient (blood leak location), or a water-repellent nonwoven fabric (both drapes) May form a blood (leakage) reservoir.

  Various blood leakage detectors or blood leakage sensors for detecting blood leakage outside this blood vessel or infusion tube are commercially available and proposed.

  For example, as a commercially available product, an electrically conductive type or a photoelectric type is known. As an electrical continuity type blood leak detector, it is used to detect and monitor changes in electrical continuity between electrodes placed on and around the indwelling needle, or to be placed in an absorption pad laid under the arm. There is one that monitors changes in electrical resistance between wires (electric wires) (see Patent Documents 1 and 2, etc.).

  As a photoelectric blood leakage detector, a light-emitting element such as an LED and a pair of light-receiving elements are used to transmit through a translucent or translucent blood absorption pad disposed on or around the indwelling needle. For detecting and monitoring the change in the transmittance of the transmitted light, and detecting the attenuation of light passing through the optical fiber disposed around the indwelling needle due to blood contact (see Patent Document 3, etc.) ).

Japanese Utility Model Publication No. 5-79468 JP 2006-110119 A JP 2010-523197 A

  The conventional blood leak detection device as described above can immediately and sensitively detect and detect blood leak occurring around the indwelling needle of the patient during dialysis. However, blood leak detection devices using these conventional detection modes cannot distinguish between leakage of blood and leakage of other liquids such as bodily fluids such as sweat and urine and infusions. There is a problem that there are many malfunctions due to leakage or adhesion of liquid.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a blood leakage detection device that is less likely to malfunction due to liquids other than blood.

The blood leakage detection device of the present invention includes a light source, a light receiving element, and a control means connected to the light source, and the light source is a lower surface of a cloth-shaped blood leakage receiving member disposed below the blood leakage location. Alternatively, the light receiving element is disposed at a position that illuminates the back surface, and the light receiving element is disposed at a position capable of receiving reflected light that is emitted from the light source and reflected by the lower surface or the back surface of the blood leak receiving member, The received light intensity of the reflected light at a predetermined first wavelength within the range of red light having a wavelength of 620 nm or more and 750 nm or less, which is a light reflection band of blood, among wavelengths of the reflected light received by the light receiving element, , wavelength of less than 620 nm, and a light-receiving intensity of the reflected light in one or more other wavelengths, Ru obtainable der.

And the control means of the blood leak detection device of the present invention comprises:
Recording means for recording the received light intensity value of the reflected light at the first wavelength and the received light intensity value of the reflected light at the other wavelength in time series measured by the light receiving element at the same timing. When,
Based on the difference between the amount of change in received light intensity at the first wavelength and the amount of change in received light intensity at the other wavelengths before and after the same time interval recorded in the recording means, the upper side of the blood leakage receiving member in indirectly determining blood leakage judging means whether a blood leakage occurs, the including.

Upper Symbol blood leakage determining means, the amount of change in the received light intensity of the first wavelength, when it falls below the amount of change in the received light intensity in the other wavelength, leakage to alarm toward an alarm of the blood leaking out A blood warning means may be included.

  Furthermore, in the blood leakage detection device of the present invention, as the other wavelength, a second wavelength within a range of green light having a wavelength of 500 nm to 560 nm and a blue light having a wavelength of 445 nm to 485 nm that is less than 620 nm. It is good also as a structure containing at least one wavelength among the 3rd wavelengths in the range.

  From the viewpoint of improving detection / detection sensitivity, a plurality of the light sources and the light receiving elements are distributed in the horizontal direction around the light leakage site and the periphery thereof. Is desirable.

  The blood leak detection device of the present invention eliminates the influence and malfunction caused by liquids other than blood, and is configured to receive blood leakage occurring around an indwelling needle placed on the arm of a dialysis patient in the form of a cloth-like blood leak such as a drape. It can be detected quickly and reliably from the lower surface side of the member.

(A) is a perspective view explaining the basic composition of the blood leak detection device of an embodiment, and (b) is a side view explaining arrangement of a light source and a light receiving element. (A), (b) is both the top views explaining the example of arrangement | positioning of the light source and light receiving element in the blood leak detection apparatus of embodiment. It is a graph which shows an example of the change of the light reception intensity | strength of three primary colors RGB of light measured in the blood leak detection apparatus, (a), (b) is a chart when blood adheres, (c) is other than blood The chart by liquid is shown. It is a graph which shows an example of the change of the light reception intensity | strength of three primary colors RGB of light measured in the blood leak detection apparatus, (a) is a chart when blood adheres, (b) is a chart by liquids other than blood. Show.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1A and FIG. 1B are diagrams illustrating the basic configuration of a blood leak detection device according to an embodiment.

  As shown in FIG. 1A, the blood leak detection device of the present embodiment is mainly composed of a light source L, a light receiving element P, and control means (controller C) connected thereto. In the figure, the light source may be displayed as LED and the light receiving element may be displayed as PD. In each figure, the components of the blood leakage detection device other than the light source L, the light receiving element P, and the control means, for example, storage means built in the control means, blood leakage warning means, blood leakage determination means, input means, Illustrations of a display device, a recording device, an alarm device for notifying the occurrence of blood leakage, a power source, wiring, a communication device, and the like are omitted.

  The blood leakage detection device according to the present embodiment is disposed at a position where the light source L illuminates the lower surface of a cloth-shaped blood leakage receiving member such as drape D, which is disposed below a portion where blood leakage is assumed to occur. The light receiving element P is disposed at a position where it can receive the reflected light emitted from the light source L and reflected by the lower surface or the back surface of the drape D or the like. Then, the controller C, which is a control means of the blood leakage detection device, including a computer or the like, among the wavelengths of reflected light received by the light receiving element P, has a wavelength of 620 nm or more and 750 nm or less (red light) that is a light reflection band of blood. The received light intensity of the reflected light at a predetermined first wavelength and the received light intensity of the reflected light at one or more other wavelengths less than 620 nm are obtained.

  An example of the arrangement of the light source L and the light receiving element P on the lower side of the blood leakage receiving member is shown in FIG. This figure is a side view of the portion of drape D, which is a cloth-like blood leakage receiving member laid under the arm of a dialysis patient or the like in FIG. A transparent plate E on which the drape D can be placed or placed is disposed below the drape D, and a plate-like member F for arranging the light source L and the light receiving element P is disposed below the transparent plate E. It is arranged.

  In addition, the drape D, the transparent plate E, the plate-like member F, etc. in this figure are drawn with emphasis on the thickness for explanation. The actual thickness is about 0.5 to 5.0 mm for drape D, about 0.5 to 2.0 mm for transparent plate E made of plastic, etc., wood, paper (corrugated cardboard), metal or plastic (sponge, polystyrene) The plate-like member F made of etc. has a thickness of about 5 to 30 mm. Further, the transparent plate E may be omitted without being provided.

  The plate-like member F for arranging the light source L and the light receiving element P is provided with a plurality of hollow cylindrical (circular in top view) recesses as shown in the figure, and the light sources L (LEDs) are respectively provided in the recesses. And the light receiving element P (PD) are arranged in pairs. With this configuration, as shown in the conceptual diagram of FIG. 1A, the reflected light on the lower surface of the cloth-like blood leakage receiving member such as drape D laid under the arm of the dialysis patient It can be measured evenly by position.

  Although a plurality of light sources L and a plurality of light receiving elements P are required, it is not always necessary to arrange each of them as a pair as shown in FIG. For example, as shown in the top view of FIG. 2A, when the planar (horizontal cross-sectional) shape of the plurality of recesses formed in the plate-like member F is a square shape, the light from one light source L (LED) May be cut out at the corners or corners where the four concave portions are common, and the light source L may be disposed at the cut-out portion.

  Also, for example, as shown in the top view of FIG. 2B, when the planar (horizontal cross-sectional) shape of the plurality of recesses formed in the plate-like member F is hexagonal, one light source L (LED) The light source L may be disposed at a portion where a corner or a corner common to the three recesses is cut out so that the light can be distributed into the three recesses. With these arrangements, the number of light sources L to be arranged can be reduced, and the initial cost of the blood leakage detection device can be reduced.

  The transparent plate E can be omitted as described above. However, if the transparent plate E is not omitted and is arranged as shown in the figure, a liquid such as blood enters each recess of the plate-like member F. Can be prevented. That is, even if blood or the like adheres to the drape D, it is sufficient to replace only the attached drape D, and the running cost of the whole blood leak detection can be reduced.

  The light source L used in the blood leakage detection device of the embodiment has at least one peak in a wavelength band including at least red light (wavelength of 620 nm or more and 750 nm or less), and can emit green light and blue light as uniformly as possible. A light source is desirable. For example, in addition to a normal halogen light source (lamp), a light bulb light source, and a fluorescent light source, a white LED or each color LED may be used in combination. In addition, as the performance of the light source L, it is desirable that the light source L can distribute light in all upper 360 ° directions (omnidirectional). Among these, white LEDs that do not emit heat rays and can be configured to be small and light are suitable. The light emission of the light source L is controlled by the controller C. The light emission may be either continuous light emission or intermittent (discontinuous) light emission.

  As the light receiving element P, a simple photodiode may be used alone or in combination, and a color sensor, a CCD, an image sensor, or the like in which charge elements are integrated may be used. In the blood leak detection device of this embodiment, it is desirable that light having a wavelength in the range of 620 nm to 750 nm (red light) and light of other wavelengths (out of range) can be received simultaneously. For this reason, a color sensor, an image sensor, or the like on which a plurality of color filters having these light wavelengths are simultaneously mounted is preferably used.

  Among them, the color sensor is red light (Red among the three primary colors of light), reflected light (first wavelength) having a wavelength of 620 nm or more and 750 nm or less, and green light (Green among the three primary colors of light). The received light intensity of reflected light (second wavelength) having a wavelength of 500 nm to 560 nm and reflected light (third wavelength) of wavelength 445 nm to 485 nm, which is blue light (Blue among the three primary colors of light). Since each color can be separated and measured simultaneously, it is preferably used in this embodiment.

  Since the actual light reception is performed in a wide wavelength band (region), the first, second, and third wavelengths described above are not only a single specific wavelength but also a light reception wavelength including the periphery thereof. It is displayed as the peak value (maximum value) of the range. For example, in the color sensor used in the following embodiments, the sensitivity peak frequency of the red (R) sensor is around 625 nm, the sensitivity peak frequency of the green (G) sensor is around 530 nm, and the sensitivity peak frequency of the blue (B) sensor. Is around 460 nm.

  The blood leakage detection device according to the embodiment has a light reception intensity of the reflected light (first wavelength) having a wavelength of 620 nm or more and 750 nm or less, that is, a light reception intensity (hereinafter referred to as “R value”) of red light (Red) in the color sensor. 2), there are two operation modes (operation modes) capable of detecting blood leakage occurring around the indwelling needle placed in the arm of the dialysis patient. Moreover, in these two operation modes, even if a liquid other than blood adheres to the upper side of the drape D, the liquid other than blood will not be mistakenly recognized as “blood”. “Malfunction” due to adhesion to the drape D is prevented.

  Detection of blood leakage and prevention of malfunction in the blood leakage detection device of the embodiment will be described.

The blood leak detection device of this embodiment has the following two types of usage. That is,
(A) Focusing on the fact that the reflectivity of red light increases when blood adheres to drapes, etc., comparing the “reflected light intensity (light receiving intensity)” of each color obtained in real time at that time From `` absolute reflection amount mode '' to detect the presence or absence of blood leakage directly without calculation etc.,
(B) Since blood reflects without absorbing red, paying attention to the fact that the decrease in reflectance of red light is less than that of other colors even when blood adheres, the current reflected light intensity (for each color) (Change amount) from the initial (initial) value or the past value stored in the storage means of the received light intensity) is obtained by calculation, and from the comparison of the "change amount" of each color, it adheres to the upper surface of the blood leakage receiving member “Relative reflectance mode” for determining / determining whether or not an object is blood.

  (A) In the case of the absolute reflection amount mode, the blood leak detection device of the present embodiment is configured such that the controller C described above measures the light reception intensity value of the reflected light in the red light (Red) measured by the light receiving element P (see above). Is the value of the received light intensity of the reflected light at other wavelengths (in the embodiment, both the “G value” for green light (Green) and the “B value” for blue light (Blue)). ) Is provided, a blood leakage warning means for issuing a warning of blood leakage to the outside when exceeding the above.

  In the case of the absolute reflection amount mode, the controller C of the blood leakage detection device performs initial reflection on the lower surface of the blood leakage receiving member such as installation in a new environment or replacement of a cloth-shaped blood leakage receiving member such as drape D. When the rate (blank or control) changes, by pressing a prepared calibration button or the like, the received light intensity of red light (Red), green light (Green), and blue light (Blue), that is, the R value, Each of the G value and the B value is set to be “0 (zero)” that is a light reception intensity reference when the button is pressed. As a result, the blood leak detection apparatus can calibrate errors due to environmental factors such as the above-described change of installation location, replacement of drape D, or replacement of dialysis patients.

  For example, as illustrated in FIG. 1A, a liquid having a red reflection color (appearance) such as blood leakage or blood adhered to the upper surface of a drape D or the like positioned above a light receiving element P such as a color sensor. In this case, the change in the intensity of the reflected light incident on the light receiving element P located on the lower side of the deposit is as shown in the chart of FIG. 3A or 3B.

  In these cases, when a red liquid such as blood adheres to the upper surface of the drape D or the like and the R value exceeds both the G value and the B value, the controller C of the blood leak detection device is determined in advance. A warning that blood leakage has been detected by light or sound from an alarm lamp or the like is transmitted (reported) to a staff member or a medical worker (blood leakage warning means). In addition to light and sound, the alarm may be simply displayed on a display device or the like. The connection between these means may be either wired or wireless.

  Here, when a liquid other than blood adheres to the upper surface of the drape D or the like, the intensity of light received by the color sensor or the like is as shown in the chart of FIG. As described above, when the attached substance is a liquid other than blood, the R value is lower than at least one of the G value and the B value, and therefore the controller C does not issue an alarm as described above. That is, the blood leak detection device of this embodiment is prevented from malfunctioning due to liquids other than these blood.

  In the case of the absolute reflection amount mode, the controller C causes the R value (red light received intensity) in these figures to inadvertently change the G value and the B value due to measurement errors and fluctuations in voltage, etc. The R value is set to a negative value slightly below 0 (zero) during the above-described calibration so as not to exceed.

  In addition to blood, examples of liquids that may adhere to this region include alcohol, disinfectant, physiological saline, and various infusions. Each of these is a substance having a light absorption band in the wavelength range of 620 nm or more and 750 nm or less, which is red light, or in the vicinity of 625 to 615 nm which is the sensitive peak frequency of the red (R) sensor of the color sensor.

  Next, also in the (B) relative reflectance mode, the controller C of the blood leakage detection device performs the same calibration so that the error due to the environmental factors described above can be eliminated. In the relative reflectance mode calibration, the R value (red light intensity) is not set to a negative value, and the blank (or control) values of the R value, G value, and B value are not necessarily set. It is not necessary to match all zeros.

  FIG. 4A is a chart showing changes in the intensity of reflected light when a red liquid such as blood adheres to the upper surface of the drape D or the like. FIG. 4B shows a chart when liquid other than blood adheres to the upper surface of the drape D or the like.

  In the case of the relative reflectance mode, the blood leak detection device of the present embodiment is configured such that the controller C described above measures the received light intensity (R value) of reflected light in red light (Red) measured by the light receiving element P, and It includes recording means for measuring the received light intensity values of reflected light at other wavelengths (in the embodiment, G value and B value) at the same timing and recording them in time series. Further, the controller C has a cloth-like shape such as a drape D based on the difference between the change amount of the R value and the change amounts of the G value and B value before and after the same time interval recorded in the recording means. A blood leakage determining means for determining whether or not the liquid attached to the upper side of the blood leakage receiving member is blood is provided.

  As in the case of the absolute reflection mode described above, the blood leak determination means provides a warning that a blood leak has been detected with a predetermined light or sound from an alarm lamp, etc. There may be provided a blood leak warning means for transmitting (reporting).

  For example, when a liquid having a red reflection color such as blood adheres to the upper surface of a drape D or the like positioned above the light receiving element P such as a color sensor, the liquid enters the light receiving element P positioned below the deposit. The change in the intensity of the reflected light is as shown in the chart in FIG.

  As described above, when a liquid having a reflection color of red, that is, a liquid having a large light absorption such as green or blue other than red adheres, the R value decreases, but the decrease width (change amount or change rate) is It becomes smaller than the change amount of G value and B value. Thereby, it can be determined that a red liquid such as blood or blood leakage has adhered to the upper surface of the drape D or the like (blood leakage determination means).

  Further, when a liquid other than blood or the like adheres to the upper surface of the drape D or the like, as shown in FIG. 4B, since the red light absorption is large, the change amount of the R value is the G value and the B value. Exceeds at least one of the changes. Thereby, the controller C determines that the attached liquid is not blood. And the alarm as mentioned above is not issued. That is, the blood leak detection device of this embodiment is prevented from malfunctioning due to liquids other than these blood.

  In any of the two modes described in detail above, the blood leak detection device of the present embodiment is provided with an indwelling needle placed on the arm of a dialysis patient from the lower surface side of a cloth-like blood leak receiving member such as drape. Blood leakage occurring in the surroundings can be detected quickly and reliably without malfunctioning due to adhesion of liquids other than blood.

  The present invention and the disclosure thereof can be implemented in various other forms without departing from the spirit or main features thereof. Therefore, the above-described embodiment is merely an example in all points, and the scope of the present invention is shown in the scope of claims, and is not restricted by the text of the specification. Further, all modifications and changes belonging to the claims are within the scope of the present invention.

  For example, the reflected light reflected from the back surface (in this case, the top surface or the side surface) of the blood leakage receiving member such as gauze or the blood leakage absorbing member member placed on or around the puncture portion of the indwelling needle is received. You may arrange | position in the position which can be, and may comprise so that the blood which oozed in this gauze etc. or oozed out from gauze may be detected.

  The blood leak detection device of the present invention is used for monitoring whether or not there is a blood leak around a person's arm where an indwelling needle is placed in a blood vessel during artificial dialysis or during dialysis. . Moreover, it can be used not only to detect blood exuding from a drape laid on the arm but also to detect gauze placed on the puncture part or blood exuding from the gauze. In addition, the present invention can be used for monitoring blood leakage in any place where a conventional blood leakage detector or blood leakage sensor is used and where blood may leak from the living body.

C controller D drape E transparent plate F plate member L light source P light receiving element

Claims (4)

A light source, a light receiving element, and a control means connected to these,
The light source is disposed at a position that illuminates the lower surface of the blood leakage receiving member disposed below the blood leakage location,
The light receiving element is disposed at a position capable of receiving reflected light emitted from the light source and reflected by the lower surface of the blood leakage receiving member,
The control means receives light intensity of the reflected light at a predetermined first wavelength within a wavelength range of 620 nm to 750 nm, which is a light reflection band of blood, among wavelengths of the reflected light received by the light receiving element. When, less than the wavelength 620 nm, and a light-receiving intensity of the reflected light in one or more other wavelengths, Ri obtainable der,
The control means includes
A recording means for recording the received light intensity value of the reflected light at the first wavelength and the received light intensity value of the reflected light at the other wavelength, measured by the light receiving element, in time series;
Based on the difference between the change amount of the received light intensity at the first wavelength and the change amount of the received light intensity at the other wavelength before and after the same time interval recorded in the recording means, the upper side of the blood leakage receiving member And a blood leakage determining means for determining the presence or absence of blood leakage occurring in the blood leakage detecting device. The other wavelengths, the second wavelength in a range of less than a wavelength of 500 nm 560 nm, and, among the third wavelength in the range of less than the wavelength 445 nm 485 nm, comprising at least one wavelength, according to claim 1 Blood leak detection device. A plurality of the light sources, each light source has at its periphery to the base point position immediately below the blood leakage locations, are distributed in the horizontal direction, the blood leak detector according to claim 1 or 2 . A plurality of said light receiving element, the light receiving element has on its periphery to the base point position immediately below the blood leakage locations, are distributed in the horizontal direction, any one of claims 1 3 The blood leakage detection device according to 1.

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