Method and system for liquid balancing for a patient

Abstract

The invention relates to a method and a system for automatic liquid balancing for a patient. During a predetermined reference time period, the patient is at least temporarily located on the bed. Each article to be used is equipped with an identifier. And the bed scale is used for weighing the weight of the bed. The reading unit reads an identifier at the object. The camera unit generates images, wherein the images show at least a bed and objects near the bed. The signal processing unit determines a weight difference, which is a difference between the weight of the bed at the first point in time and the weight of the bed at the second point in time. The signal processing unit calculates a liquid balance for the patient, which is a total amount of liquid delivered to the patient within a reference period of time minus an amount of liquid exiting the patient within the reference period of time. To this end, the signal processing unit uses a weight difference, i.e. Which items are moved towards or away from the bed, and uses a respective amount of liquid that each moved item can contain.

Description

Technical Field

[0001] The present invention relates to a method and system for automatic fluid balancing for a patient. Background Art

[0002] The object of the present invention is to provide a method and a system which can be used when caring for a patient who is at least temporarily lying in bed and which are intended to reduce the risk of the patient suffering a health hazard. Summary of the invention

[0003] This object is achieved by a method having the features of claim 1 and by a system having the features of claim 12. Advantageous embodiments are described in the dependent claims. If this is appropriate, an advantageous embodiment of the method according to the invention is also an advantageous embodiment of the system according to the invention, and vice versa.

[0004] The method according to the invention and the system according to the invention are able to automatically carry out a fluid balance for a patient and thus provide a fluid balance for the patient. The method according to the invention is carried out using the system according to the invention.

[0005] A reference time period is pre-determined, which parameter time period has a length of 24 hours, for example. The liquid balance calculated according to the invention is the difference between the amount of liquid delivered to the patient in total within the pre-determined reference time period and the amount of liquid discharged from the patient in the reference time period. The amount is preferably specified as a mass. The liquid delivered to the patient in total during the reference time period also includes liquid that the patient actively eats, for example by drinking from a drinking vessel. The liquid discharged from the patient in total within the reference time period also includes liquid that the patient secretes or actively excretes outside the bed.

[0006] If the difference and therefore the fluid balance is greater than zero, the patient last consumed fluid within the reference period, otherwise last (per Saldo) consumed fluid.

[0007] During the reference time period, the patient lies in bed continuously or at least temporarily. In order to care for the patient, at least one movable object is used or can be used. Movable means that the object can be moved during the care of the patient and relative to the patient. The object used or can be used or at least one, preferably each object is respectively equipped with a machine-readable identifier. The identifier distinguishes the object from other objects used or each other object used, at least but from each other object. But at least each object used or usable that can accommodate and provide liquids is equipped with a machine-readable identifier.

[0008] The identifier of the object is stored, for example, in an NFC tag, wherein the NFC tag is, for example, in the form of an RFID tag. Or the identifier is in the form of a barcode or a QR code on the object. The identifier may also include an alphanumeric character sequence and / or at least one symbol. The identifier may also include a plurality of components. The contour and / or the color or at least one color of the object may also belong to the identifier.

[0009] A computer-evaluable object list is predefined. The object list is stored, for example, in a data memory of the system. The object list comprises an entry for each identified object used or available for use. The entry comprises information about the machine-readable identifier of the object and at least one of the following information:

[0010] - information about the weight of the object,

[0011] - Information about the amount of liquid the object can hold.

[0012] It is possible that the entry about an object having an identifier includes the information that the object cannot contain liquids.

[0013] The system according to the invention comprises a reading unit with at least one reading device and a camera unit with at least one camera. The or each reading device respectively has a reading area. The or each reading device is able to read a machine-readable identifier if the identifier is located in the reading area. The or each camera respectively has a field of view. Within a predetermined reference time period, the bed is located in the respective reading area of ​​each reading device and in the respective field of view of each camera. Preferably, neither the bed, the reading device nor the camera are moved within the reference time period, in particular not relative to each other.

[0014] The camera or each camera is capable of generating at least one image, preferably a sequence of images, respectively. These images show the bed, optionally the patient on the bed, and optionally the object or each object and the person or each person, insofar as the object and the person are located in the field of view of the camera. The camera is capable of generating a signal, wherein the signal comprises the generated image or the generated sequence of images. The reading device or each reading device is capable of reading the corresponding machine-readable identifier of the object in the reading area of ​​the reading device and generating a signal comprising the reading result.

[0015] The system according to the invention further comprises a bed scale. The bed scale is capable of measuring the current weight of the bed. If the patient is in bed at the time of measurement, the measured weight includes the weight of the patient in addition to the weight of the bed (including the weight of optional bedding). Based on the measured weight, it can be clearly determined whether the patient is in bed at the time of measurement or whether the bed is empty at the time of measurement.

[0016] The signal processing unit of the system can at least temporarily read access to the object list. The signal processing unit can be a component of a portable computer, such as a smartphone or tablet, or also a component of a stationary computer, such as a PC.

[0017] The corresponding signals of the or each reading device and of the or each camera are transmitted to a signal processing unit, preferably wirelessly via radio waves, alternatively by means of a data cable. The signal processing unit processes the received signals.

[0018] The method according to the invention comprises the following steps, and the system according to the invention is designed to perform the following steps:

[0019] The bed scale repeatedly measures the current weight of the bed within a reference time period. The signal processing unit determines a first time point and a subsequent second time point, wherein the bed scale has measured the current weight of the bed at both time points and the patient is lying on the bed at both time points. The first time point is preferably located in the first third, particularly preferably in the first eighth, of the reference time period, and the second time point is located in the last third, particularly preferably in the last eighth. The bed scale preferably measures the current weight at least three times within the reference time period, particularly preferably at a fixed sampling rate.

[0020] The signal processing unit derives at least one weight difference. The weight difference or weight difference is the difference between the weight of the patient at the second time point and the weight of the patient at the first time point - more generally: the difference between the weight at a later time point and the weight at an earlier time point. The weight difference does not depend on the weight of the bed, because the bed scale weighs the weight of the bed not only at the first time point but also at the second time point, and the patient is in the bed not only at the first time point but also at the second time point.

[0021] The reading unit reads the corresponding identifier of the object in the reading area of ​​the reading device. The camera unit generates at least one image, preferably a sequence of images, wherein the or each image shows at least the bed and furthermore each movable object and each person that is in the vicinity of the bed and therefore in the field of view of the camera of the camera unit.

[0022] The signal processing unit detects each object which has come into the vicinity of the patient and / or has been removed from the vicinity of the patient during the reference time period and is therefore in the reading area of ​​at least one reading device and / or in the field of view of at least one camera. For this detection, the signal processing unit uses the signal or each signal of the reading device and the signal or each signal of the camera.

[0023] It is possible that the signal processing unit recognizes and detects the object based not only on the signal of the reading unit but also on the signal of the camera. For example, the reading unit reads out a machine-readable identifier and recognizes an optically detectable identifier of the same object in the image of the camera by image processing.

[0024] The signal processing unit calculates the fluid balance for the patient. The term fluid balance has already been defined above. The fluid balance relates to a predefined reference time period. To calculate the fluid balance, the signal processing unit uses

[0025] - derived weight difference,

[0026] - information about which objects have arrived near the bed during a reference period,

[0027] - if so, information on which objects have been removed from the vicinity of the bed during a reference period, and

[0028] - Based on the list of items, the amount of liquid and / or weight of these items.

[0029] The signal processing unit determines based on the signals of the reading unit and / or based on the signals of the camera unit which objects have arrived in the vicinity of the bed and which objects have been removed again.

[0030] The object list includes, for each used or usable object and thus also for each detected object, information about the net weight of the object and / or about the amount of liquid that the object can accommodate.

[0031] The method according to the invention and the system according to the invention can be applied to a patient, more specifically, in particular when the patient is in a hospital, in a nursing institution or at home and when the patient is medically cared for and / or cared for. If the patient does not take enough liquid within a predetermined reference time period, the patient may suffer from health damage. The delivered liquid should at least replace the discharged liquid to a sufficient extent. If the liquid balance is negative and is less than a predetermined lower limit, there is a risk of the patient becoming dehydrated. Dehydration (dehydration disease) may cause the patient's water balance and electrolyte balance to be destroyed, and the patient suffers from health damage as a result. On the other hand, if the liquid balance is positive and greater than a predetermined upper limit, there is a risk of liquid being deposited in the patient's tissues and edema occurring, which is also undesirable.

[0032] The fluid balance for a patient within a predefined reference time period is influenced by various influencing variables. Since the system according to the invention comprises various sensors and object lists, and the method according to the invention processes the signals of these sensors and object lists, a large number of these various influences can be quantitatively determined in order to calculate the fluid balance.

[0033] The invention can be used in conjunction with the following steps, namely that the patient is weighed outside the bed, more precisely in particular immediately before and / or immediately after the reference time period. It is possible to determine the difference between the two patient weights. However, the invention eliminates the need to weigh the patient outside the bed. Precisely in clinical everyday life, there is often a lack of personnel and time for this. In addition, the invention makes it possible to install the components of the system according to the invention for the patient once and connect them to each other, and then repeatedly calculate the fluid balance for different time periods, also for different patients, without requiring human assistance for the calculation. In addition, if the patient is weighed only once before the reference time period and once after the reference time period, it is usually not sufficient to provide a reliable fluid balance.

[0034] According to the invention, a reading unit and a camera unit are used. As a result, the signal processing unit is able to identify in particular which objects have arrived in the vicinity of the bed and therefore in the vicinity of the patient on the bed and which objects have been removed from the bed and therefore from the patient again. The signal processing unit extracts information from the object list: which amount of liquid each object can respectively accommodate and is therefore delivered to the patient when the object arrives in the vicinity of the patient. In general, it can also be determined whether the object with liquid is actually directed to the patient's mouth. With the help of the object list, processes in which liquid is delivered to the patient can also be distinguished from processes in which objects are used in the vicinity of the patient without delivering liquid to the patient, such as tableware or books or medical instruments, or from processes in which a drinking vessel with liquid is moved to the patient, but the patient does not drink liquid from the drinking vessel.

[0035] In one embodiment, the bed scale measures the current weight of the bed more than twice within a reference time period, preferably at a predetermined sampling rate. A signal processing unit determines the time course of the weight of the bed, for which purpose the signal processing unit receives and processes the signal of the bed scale. The signal processing unit uses the time course of the bed weight in order to calculate a fluid balance for the patient. The time course relates at least to the time interval between the first time point and the second time point, and optionally to the entire reference time period.

[0036] With the aid of this design, the signal processing unit can in many cases determine with greater safety how much liquid the patient has taken in while he is lying in bed. By processing the signals of the reading unit and the camera unit, the signal processing unit detects an event in which an object is brought to the patient's body and then removed again, or determines that such an event has not occurred. By evaluating the object list, the signal processing unit identifies which amount of liquid the object can accommodate and / or how much the object weighs without liquid. The temporal course of the bed weight provides information on how the measured weight of the bed with the patient and thus the weight of the patient has changed. This information is always associated with the corresponding time point of the measurement or detection. From this information, the signal processing unit determines how much liquid the patient has actually taken in. With the aid of the signals of the reading unit and the camera unit, this situation can be distinguished from a situation in which the patient on the bed grabs an object or an object is brought to the bedside or to the bed, without the patient taking any liquid.

[0037] In a refinement of the design, the signal processing unit automatically searches for the departure time point, the subsequent return time point, and a third time point between the two time points. The signal processing unit performs the search so that the three time points cumulatively have the following characteristics:

[0038] - All three time points are within a pre-given reference time period.

[0039] - The respective current weight of the bed has been measured at all three time points.

[0040] - The patient was in bed not only at the departure time point but also at the return time point.

[0041] - At the third time point, the patient was outside of the bed.

[0042] In particular, the signal processing unit uses the first time point as the departure time point, and uses the second time point as the return time point.

[0043] As already mentioned, the signal processing unit infers from the measured values ​​of the bed scale whether the patient is in bed or outside of the bed at the measuring time. It is possible, but not necessary due to the bed scale, to use other sensors for this purpose.

[0044] If the signal processing unit has found three such time points, the signal processing unit performs the following steps:

[0045] - The signal processing unit calculates the difference between the measured weight of the bed at the departure time point and the measured weight of the bed at the return time point.

[0046] - The signal processing unit uses the calculated difference to calculate the fluid balance.

[0047] At a third time point, i.e., in the time interval between the departure time point and the return time point, the patient may have already released liquid outside the bed, for example, gone to the toilet to have a bowel movement, and on the other hand may have already consumed liquid outside the bed. The measured difference approximately indicates the difference between the release of liquid and the intake of liquid in the time interval between the departure time point and the return time point. This design can be implemented in conjunction with at least one weighing of the patient outside the bed. However, with this improvement, it is not necessary to weigh the patient outside the bed in this time interval.

[0048] In one embodiment, the system comprises at least one volume flow sensor. The volume flow sensor can measure the volume flow of the liquid through the fluid guiding unit, alternatively or additionally the mass flow of the liquid. More precisely: the volume flow sensor directly measures the volume flow or the mass flow or a variable related to the volume flow and / or the mass flow.

[0049] According to the design, during the period when the fluid guiding unit is connected to the patient's body, the volume flow sensor measures the volume flow or mass flow of the liquid passing through the fluid guiding unit. The liquid can flow into the patient's body through the fluid guiding unit or flow out of the patient's body through the fluid guiding unit. It is possible that the liquid flows into the patient's body through the fluid guiding unit, and the same or different liquid flows out of the patient's body and through another fluid guiding unit. For example, an infusion agent flows from a bag into the patient's body through the fluid guiding unit, and urine flows out of the body and into a urine bag. The fluid guiding unit is connected to the patient's body at least in the time interval between the first time point and the second time point. The volume flow or mass flow is measured at least in this time interval.

[0050] In one implementation, a fluid guiding unit is used so that the liquid flows through the fluid guiding unit in two opposite directions in sequence. In this case, the volume flow sensor preferably additionally determines the current flow direction. The signal processing unit receives the signal of the volume flow sensor and uses the measured volume flow to calculate the liquid balance.

[0051] This embodiment further improves the accuracy and reliability of the calculation of the liquid balance according to the invention.

[0052] Notes:

[0053] A fluid guiding unit is understood to be a component which can guide a fluid along a path, wherein the path is predetermined by the design and arrangement of the component. For example, a fluid guiding unit comprises a pipe or a hose.

[0054] - Volume flow is understood to be the volume flowing through the fluid guiding unit per unit time. Mass flow is correspondingly understood to be the mass flowing through the fluid guiding unit per unit time. The liquid taken in or discharged by the patient within the reference time period usually has a high proportion of water and therefore has a specific density approximately equal to the specific density of water. Therefore, the volume flow is approximately proportional to the mass flow.

[0055] In one embodiment, the system according to the invention comprises a urine bag scale. The urine bag is at least temporarily connected to a patient during a reference time period. The patient discharges urine into the urine bag by means of a hose and preferably by means of a catheter. The signal processing unit determines the time course of the weight of the urine bag and processes the signal of the urine bag scale for this purpose. The time course is measured at least in the time interval between a first time point and a second time point. The signal processing unit uses the time course to calculate the fluid balance.

[0056] According to this design, the signal processing unit processes the time course of the weight of the urine bag. As a result, the signal processing unit can determine the volume flow or mass flow into the urine bag. On the other hand, the signal processing unit can detect the event that the urine bag is replaced or emptied. This process usually leads to a sudden change in the measured weight of the urine bag.

[0057] In one embodiment, the system according to the invention comprises a table scale. The table scale is capable of measuring the weight of a table. During a reference time period, the table is at least temporarily located near a patient. The table can stand on the ground or can be connected to a bed. Objects used for caring for the patient or usable for this purpose can be stored on the table. Some of these objects may contain liquids, such as beverages or solid foods. A signal processing unit determines the time course of the weight of the table and processes the signal of the table scale for this purpose. The time course at least includes the time interval between a first time point and a second time point. The signal processing unit uses the determined time course to calculate the liquid balance.

[0058] With the aid of this embodiment, the signal processing unit can in particular determine the process in which a container with liquid is placed on the table, gradually emptied and then removed from the table again. The signal processing unit preferably additionally detects the container with the aid of signals from the reading unit and / or the camera unit. By reading access to the object list, the signal processing unit determines: how much the container weighs and / or how much liquid the container can accommodate. Since different information is combined with one another, the reliability of the calculation of the amount of liquid that the patient consumes from the container increases.

[0059] According to the invention, the reading unit comprises at least one reading device. The camera unit comprises at least one camera. In one design, the reading unit comprises at least two reading devices and / or the camera unit comprises at least two cameras. The viewing directions of the reading devices are preferably different from one another, and the viewing directions of the cameras are likewise different from one another. The signal processing unit determines the respective movement of each object relative to the bed within a reference time period and additionally identifies the object based on an identifier. In particular, the signal processing unit is thereby able to determine in many cases whether liquid is brought to the patient and / or liquid is removed from the patient and / or liquid is neither brought to the patient nor removed from the patient in the object. The signal processing unit uses each determined relative movement to calculate the liquid balance.

[0060] Typically, the patient drinks liquid from the container at least once within the reference time period. The container is designed to receive drinkable liquid and is directed to the patient's mouth. For example, the container is placed on a support surface of a patient table, and the patient picks up the container and drinks from it. Or the container is held in front of the patient's mouth. According to the invention, the container is also provided with a unique machine-readable identifier. The weight of the container and / or the amount of liquid that the container can receive is stored in the object list.

[0061] By means of the following design, the amount of liquid that the patient has consumed by drinking from the container within the reference period is taken into account in the liquid balance with relatively high reliability. The signal processing unit executes the following sequence at least once:

[0062] - A signal processing unit detects the event that the container is introduced to the patient's mouth.

[0063] - The signal processing unit determines how long the patient has been drinking from the container.

[0064] - The signal processing unit determines an approximation of the amount of liquid the patient has ingested from the container.

[0065] - The signal processing unit uses the approximation to calculate the fluid balance.

[0066] For the detection and for the determination, the signal processing unit uses at least one signal from the reading unit, at least one signal from the camera unit and the object list.

[0067] By means of the machine-readable marking and the camera unit, the movement of the object relative to the patient's bed can be well tracked. Thus, the signal processing unit can detect that an object in the shape of a container is directed to the patient's mouth. Furthermore, the signal processing unit can detect events in which liquid is poured out or that the patient directs the container to his mouth but does not drink.

[0068] The following design takes into account the possibility that while the patient is lying in bed, the patient excretes liquid and the liquid is collected by textiles, wherein these textiles are located on the bed and there between the patient and the bed or on the patient's body. In particular, the mattress or the patient's clothes are textiles. For example, the patient excretes liquid. Since this liquid remains on the bed, it does not cause a change in the weight measured by the bed scale or the optional table scale.

[0069] According to this design, the signal processing unit can detect that the used object is replaced by a new object, i.e., for example, the event that bedding and / or the patient's clothes are replaced. For this detection, the signal processing unit uses the signal of the reading unit and / or the signal of the camera unit.

[0070] Before the replacement, the object has received the moisture excreted by the patient in bed. Usually, the new object is of the same type as the replaced object, but is new and therefore dry. Therefore, the difference between the weight of the used object and the new object is approximately equal to the weight of the liquid released by the patient in the bed into the used and then replaced object. It is possible to measure the weight of the used object before the replacement and the weight of the new object. However, with the help of the following implementation, the necessity of having to measure the weight of the object separately is avoided.

[0071] According to this implementation, on the one hand, the weight of the bed is measured at a point in time before replacement, i.e., at a point in time when the old object, which may have contained liquid, is still located on the bed. On the other hand, the weight of the bed is measured after replacement, i.e., at a point in time when the new object, i.e., the object that has not yet contained liquid from the patient to a significant extent, is located on the bed. Either at these two points in time, the patient is located on the bed. For example, the first point in time is used as the point in time before replacement and the second point in time is used as the point in time after replacement. Or at these two points in time, the patient is located outside the bed. As already explained, the signal processing unit can clearly determine based on the weight that has been measured by the bed scale at the measurement time point: whether the patient is located on the bed or outside the bed at the measurement time point. The measured weight of the bed before replacement minus the measured weight of the bed after replacement approximately provides the weight of the liquid that the patient has released into the object before replacement.

[0072] Another implementation does not necessarily require that the object that contains or can contain the patient's fluid be replaced within a predetermined reference time period and that the replacement be detected. According to this other implementation, the signal processing unit detects two time points within a predetermined reference time period, at which the current weight of the bed has been measured and the patient is not on the bed. The signal processing unit calculates the difference between the weight of the bed at the later time point and the weight of the bed at the earlier time point. In many cases, this difference is sufficiently accurate to correspond to the amount of fluid that the patient has excreted on the bed between the earlier time point and the later time point. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] The present invention is described below based on embodiments. In this case,

[0074] Figure 1 Schematically shows a patient on a hospital bed, various items for caring for the patient, and a fluid balance system according to the present invention;

[0075] Figure 2 Schematically shown from different viewing directions Figure 1 patients and objects;

[0076] Figure 3 It is shown by way of example which signals and other information the signal processing unit processes in order to calculate the fluid balance. DETAILED DESCRIPTION

[0077] Figure 1 and Figure 2 A liquid balancing system 20 according to the invention is schematically shown. Identical reference numerals have the same meaning.

[0078] Application Examples

[0079] The liquid balance system 20 is used to determine the liquid balance for the patient 10. The liquid balance relates to a predetermined reference time period T and is the difference between the amount of liquid delivered to the patient 10 in total during the reference time period T and the amount of liquid that left the patient 10 in total during the reference time period T. The reference time period T has a length of 24 hours, for example.

[0080] The patient 10 lies continuously or at least temporarily in a bed during a reference period of time T, currently on a bed 30 located in a room 12 of a hospital. The bed 30 remains in its position during the reference period of time T. It is possible that the patient 10 temporarily leaves the bed 30. The bed can also be a conventional bed or a couch and can be located in a room of a residence or a nursing facility.

[0081] While the patient 10 is lying on the bed 30, the patient wears clothing 38. The patient 10 is covered with a bed linen 34 or lies on the bed linen 34, wherein for example a bed sheet and a pillow belong to the bed linen 34. In addition, a mattress 36 is located between the patient 10 and the bed 34.

[0082] Next to the bed 30 there is a patient table 40 on which objects can be stored. The patient table 40 comprises a storage surface, an articulated arm and a support leg. In addition, next to the patient table 30 there is a movable holding device 84 in the form of a movable coat rack, at which the infusion bag 82 is suspended. In the reference time period T, the hose 56 connects the infusion bag 82 to the body of the patient 10, more precisely continuously or at least temporarily. The liquid from the infusion bag 82 flows into the body of the patient 10 via the hose 56. The holding device 54 at the bed 50 holds the urine bag 50. The hose 58 connects the body of the patient 10 to the urine bag 50, more precisely continuously or at least temporarily.

[0083] Components of a fluid balance system

[0084] - Bed scale 32,

[0085] - Table scale 42,

[0086] - a urine bag scale 52, and

[0087] -Volume flow sensor 80

[0088] The liquid balancing system 20 belongs to this embodiment.

[0089] The bed scale 32 is capable of measuring the weight Gew(30) of the bed 30. In this embodiment, the bed 30 stands on the external bed scale 32. When the patient 10 lies on the bed 30, the bed scale 32 measures the sum of the weight of the bed 30 and the weight of the patient 10. When the patient 10 has left the bed 30, the bed scale 32 measures the weight of the empty bed 30 plus the weight of the bedding remaining in the bed 30.

[0090] The table scale 42 is able to measure the weight Gew(40) of the patient table 40. In this embodiment, the patient table 40 stands on the table scale 42. If at least one object is located on the storage surface of the patient table 40, the table scale 42 additionally measures the weight of the or each object on the storage surface.

[0091] The urine bag scale 52 can measure the weight Gew (50) of the urine bag 50. The volume flow sensor 80 measures the volume flow Vol' (56) or the mass flow from the infusion bag 82 through the hose 56. It is possible to deliver liquid from another container or device to the body of the patient 10, or to suck the liquid away or drain it in another way, and also measure the corresponding volume flow or mass flow. The corresponding sensor can be an integral part of the device. The sensors 32, 42, 52 and 80 preferably measure the corresponding physical variables repeatedly at a fixed sampling frequency.

[0092] In order to take care of the patient 10 while the patient 10 is lying on the hospital bed 30, a plurality of movable objects 60 are used. Exemplarily, a beverage bottle 64, a cup 66, bedding 34, a mattress 36, and clothes 38 of the patient 10 are shown as the movable objects 60.

[0093] At least one, preferably each object 60 is respectively provided with a machine-readable identifier 62, at least each object that can contain a liquid is provided with a machine-readable identifier. The identifier 62 distinguishes the object 60 from each other object or at least from each other object, which is used to care for the patient 10. Therefore, different copies of the same object 60 can also have the same identifier 62. The identifier 62 has, for example, the form of an RFID tag, a barcode, a QR code, a specific pattern or symbol, or an alphanumeric character sequence. The color and / or contour of the object 60 can also be used as an identifier 62 alone or as a color-contour combination. The identifier 62 is preferably applied to an object multiple times so that at least one identifier 62 can be read.

[0094] The liquid balancing system 20 comprises a reading unit 72 having at least one reading device 74, preferably a plurality of reading devices 74, and a camera unit 76 having at least one camera 78, preferably a plurality of cameras 78. The reading device 74 or each reading device 74 has a reading area. The camera or each camera 78 has a field of view with a central viewing direction (viewing axis). The fields of view are preferably different from each other, and at least two viewing directions are arranged tilted or skewed with respect to each other.

[0095] Each reading device 74 and each camera 78 is preferably fixedly mounted, for example at the ceiling or wall of the room 12 or at the patient table 40 or at the patient bed 30. Therefore, the reading device 74 and the camera 78 maintain their position relative to the patient bed 30 during the reference time period T. Therefore, during the reference time period T, the patient bed 30 is continuously located in the or each reading area and in the or each field of view.

[0096] The reading device or each reading device 74 is capable of reading or otherwise detecting a respective identifier 62 for each object in the reading area of ​​the reading device 74. Read(62) denotes the reading result of the reading device 74. The reading device 74 preferably samples the identifier 62 repeatedly at a sampling frequency. The camera or each camera 78 is capable of recording an image Abb(60), preferably a sequence of images having a sampling frequency. Each reading device 74 and each camera 78 generates a signal having a respective reading result Read(62) or a respective image Abb(60) or a sequence of images, respectively. The image Abb(60) of the camera 78 thus shows

[0097] - 30 beds,

[0098] - the patient 10 when the patient 10 is located on the bed 30, and

[0099] -Every person and object 60 near the bed 30.

[0100] The liquid balancing system 20 further comprises a signal processing unit 22 having a data memory 24 and a processor 26. The processor 26 can at least temporarily read access to the data memory 24 and execute stored programs. The signal processing unit 22 can be a component of a smartphone or a tablet or other portable computer.

[0101] How a Liquid Balance System Works

[0102] The signal just described is transmitted to the signal processing unit 22 preferably wirelessly via electromagnetic radio waves 90 . Figure 3 It is shown by way of example which signals and other information the signal processing unit 22 receives and processes.

[0103] The signal processing unit 22 receives signals from each reading device 74 and each camera 78, respectively, and processes the received signals. By evaluating the signals of the reading devices 74, the signal processing unit 22 detects and identifies each machine-readable identifier 62 in the reading area of ​​the reading device 74, and thereby detects and identifies the identified object 60. Optionally, the signal processing unit 22 determines from the variable field strength of the signal of the reading device 74: how the object 60 with a specific identifier 62 moves relative to the bed 30. The image processing unit of the signal processing unit 22 processes the signals of the camera 78, and thereby detects each person and each object in the field of view of the camera 78.

[0104] In one embodiment, the image processing unit uses a classifier. The classifier detects and classifies objects in the image Abb (60) of the camera 78. The classifier is preferably trained in advance using samples, for which purpose a machine learning method is used. For example, the classifier is implemented as a neural network. The embodiment with a classifier creates redundancy and increases the reliability of correctly detecting the movement of the object 60: the object 60 can be classified on the one hand according to its identifier 62 and on the other hand according to its contour.

[0105] Overall, the signal processing unit 22 determines the respective position and movement of each object 60 with an identifier 62 relative to the bed 30 and thus relative to the patient 10 by means of the classification. The signal processing unit 22 also determines whether the object 60 was located at the mouth of the patient 10 for a sufficient period of time. If the object 60 is a beverage bottle 64 or a cup 66, this detection is a sign that the patient 10 drank liquid from the object 60 or spilled liquid. This distinction cannot be made reliably by evaluating the signal of the scale alone.

[0106] Furthermore, the signal processing unit 22 preferably also wirelessly receives signals from the bed scale 32, the table scale 42, the urine bag scale 52 and the volume flow sensor 80, respectively, via radio waves 90. In this embodiment, the signal processing unit 22 determines the following time course in the reference time period T:

[0107] the time course of the weight of the bed 30 , wherein the measured weight includes the weight of the patient 10 if the patient 10 is lying on the bed 30 , and otherwise only includes the measured weight of the bed 30 (including bedding and mattress),

[0108] - a time course of the weight of the patient table 40 , wherein if at least one object 60 is located on the patient table 40 , the measured weight includes the weight of this object 60 ,

[0109] - the time course of the weight of the urine bag 50, and

[0110] The time course of the volume flow through the hose 56 .

[0111] The signal processing unit 22 preferably computationally compensates for short-term oscillations over time. Such oscillations are caused by short-term and small movements of the patient 10 or a caregiver or an external vibration source and do not significantly affect fluid balance. For example, the signal processing unit 22 applies a low-pass filter to the signals of the sensors 32, 42, 52, 80, respectively.

[0112] At least temporarily, the signal processing unit 22 has read access to a computer-evaluable object list 70. The object list 70 is stored, for example, in the data memory 24. The object list 70 contains an entry for each object 60 that can be detected based on the identifier 62 and / or by the optional classifier described above. The entry contains

[0113] - information about the identifier 62, and

[0114] - information about the weight of the object 60,

[0115] - and information about the mass and volume of liquid that the object 60 can accommodate.

[0116] In the case of a drinking vessel as object 60, the information includes, for example, information about the volume and / or net weight of the drinking vessel. Of course, it is possible that the object cannot contain liquids or is not used to contain liquids. If the object is a plate or a bowl and can contain food, the list includes information about the average amount of liquid contained in the contained solid food.

[0117] Calculation and Assessment of Fluid Balance

[0118] Signal processing unit 22 calculates a fluid balance for patient 10. In this embodiment, the fluid balance is the mass or volume of fluid that has been delivered to patient 10 in total during a reference time period T minus the mass or volume of fluid that has been removed from the patient in total during the reference time period T.

[0119] The calculated fluid balance can be positive or negative. If the fluid balance is positive, the patient 10 has consumed more fluid than the patient excreted during the reference time period T. Otherwise, the patient has excreted more fluid than the patient has consumed. In one design, a value range with an upper limit and optionally a lower limit is predefined. The upper limit is greater than zero and the lower limit is less than zero. The fluid balance for the patient 10 during the reference time period T should be within this value range. If the fluid balance is less than the lower limit, the patient 10 has consumed too little fluid during the reference time period T. There is then a risk that the patient 10 will become dehydrated. If the fluid balance is greater than the optional upper limit, there is a risk that fluid will be deposited in the tissues of the patient 10, which is also undesirable.

[0120] The signal processing unit 22 preferably checks whether the liquid balance is within a value range for a reference time period T or whether the liquid balance is less than a lower limit or greater than an upper limit. If the liquid balance is outside the value range, the signal processing unit 22 generates a corresponding message and causes the message to be output in at least one form perceptible to a person, more precisely preferably in a form perceptible to a recipient outside the room 12. The message preferably indicates that the patient has taken too much or too little liquid. In one embodiment, a corresponding notification is generated and output even if the liquid balance is within the value range. A liquid balance far outside the value range can also be a symbol for the following aspects: liquid intake is not detected or liquid intake or a device of the system is working incorrectly.

[0121] Patient 10 ingests liquids, in particular by:

[0122] The liquid is delivered from the infusion bag 82 and through the hose 56 to the patient 10. This supply causes a volume flow and a mass flow through the hose 56, and the volume flow sensor 80 measures this volume flow and this mass flow.

[0123] A drinking vessel, such as a beverage bottle 64 and / or a cup 66, is placed on the patient table 40 - more precisely: on the support surface of the patient table 40. The patient 10 grabs the drinking vessel 64, 66, drinks from the drinking vessel 64, 66 and places the completely or at least partially emptied drinking vessel 64, 66 back on the patient table 40. The drinking vessel 64, 66 on the patient table 40 contributes to the measured weight of the patient table 40. The table scale 42 continuously measures the weight of the patient table 40. If the patient 10 holds the drinking vessel 64, 66 in his hand, this weight contributes to the weight measured by the bed scale 32. The signal processing unit 22 preferably compares the time course of the weight of the hospital bed 30 with the time course of the weight of the patient table 40 in order to determine whether the patient 10 actually consumes liquid from the drinking vessel 64, 66 that was previously located on the patient table 40.

[0124] A caregiver (not shown) brings the drinking vessel 64, 66 to the mouth of the patient 10, and the patient 10 drinks from the drinking vessel 64, 66 without placing the drinking vessel 64, 66 on the patient table 40. The weight of the bed 30 increases due to the drinking.

[0125] In particular, the patient 10 releases the fluid by:

[0126] - Urine flows from the body of the patient 10 through the hose 58 into the urine bag 50. The urine bag scale 52 measures the weight of the urine bag 50, and the signal processing unit 22 determines the time course of the urine bag weight. If the measured weight suddenly decreases, the urine bag 50 has been replaced by a new empty urine bag, and the signal processing unit 22 takes this into account.

[0127] The patient 10 leaves the bed 30 and goes to the toilet to excrete fluid and / or defecate. Using the signal of the bed scale 32, the signal processing unit 22 determines the weight of the patient 10 before the patient 10 leaves the bed and determines the weight after the patient 10 gets back on the bed 30. The weight difference corresponds approximately to the amount of fluid excreted.

[0128] - For example, because the patient 10 secretes liquid, the patient 10 releases liquid onto the clothing 38 or the mattress 36. If the worn clothing 38 or the used mattress 36 is replaced with new clothing 38 or a new mattress 36, the amount of liquid released by the patient 10 in this way can be determined approximately. The difference in weight between the used clothing / mattress and the new clothing / mattress approximately indicates the amount of liquid released. This difference is derived, for example, from the difference: the weight of the bed 30 and the patient 10 before the replacement of the items minus the weight of the bed 30 and the patient 10 after the replacement of these items. In many cases, the image processing unit is able to detect the event that the clothing 38 and / or the mattress 36 are replaced.

[0129] The following events do not usually affect fluid balance:

[0130] - Cutlery or books or other objects not containing liquids are placed on or removed from the patient table 40 .

[0131] Note: Since the signal processing unit 22 determines the time profile and derives the difference therefrom, the weight of the empty hospital bed 30 or the weight of the empty patient table 40 is not necessarily required.

[0132] In this embodiment, the following possibility is considered: objects are placed on the patient table 40 and / or removed from the patient table 40 successively or simultaneously. Each object changes the weight of the patient table 40, and the table scale 42 weighs this weight. The weight of the objects on the patient table 40 thus influences the time course of the weight of the patient table 40, wherein the signal processing unit 22 thus determines this time course as described above. The signal processing unit 22 also identifies each object 60 placed on or removed from the patient table 40 based on the identifier 62, more precisely at least when the object 60 can accommodate liquid. By reading access to the object list 70, the signal processing unit 22 determines how much liquid the identified object 60 can accommodate. The signal processing unit 22 determines how much liquid the patient 10 has taken in total from the objects standing on the patient table 40 within the reference time period T. For this purpose, the signal processing unit 22 uses the determined time course of the weight of the patient table 40 and the amount of liquid that the identified objects 60 on the patient table 40 can hold according to the object list 70. In particular, the signal processing unit 22 determines objects that change the weight of the patient table 40 but do not hold liquid and therefore do not contribute to the liquid balance, such as cutlery or books. If the object 60 does not carry an identifier, it is preferably disregarded when calculating the liquid balance. In addition, the signal processing unit 22 optionally determines an event in which the patient 10 pours liquid out of the identified drinking vessel 60 and approximately takes this into account when calculating the liquid balance.

[0133] It is possible that a full drinking vessel, such as a beverage bottle 64 or a cup 66, has already been placed on the patient table 40 before drinking, and an empty drinking vessel is placed on the patient table 40 again after drinking. As a result, the measured weight of the patient table 40 changes. The following possibility is conceivable: the caregiver brings the drinking vessel 64, 66 to the mouth of the patient 10 and the patient 10 drinks from the drinking vessel 64, 66 without depositing the drinking vessel 64, 66 on the patient table 40. In this case, the drinking vessel 64, 66 does not change the measured weight of the patient table 40.

[0134] The image processing unit of the signal processing unit 22 detects events in which the drinking vessel 64, 66 is brought to the mouth of the patient 10 and events in which the drinking vessel 64, 66 is removed from the mouth of the patient 10 again. The signal processing unit 22 identifies the drinking vessel 64, 66 based on the identifier 62 and determines by image evaluation that the drinking vessel 62 is located in front of the mouth of the patient 10. The signal processing unit 22 determines how much liquid the drinking vessel can hold by reading access to the object list 70. The signal processing unit 22 preferably uses the assumption that the patient 10 consumes this amount of liquid while the drinking vessel 64, 66 is held in front of the mouth of the patient 10.

[0135] In one embodiment, the possibility is taken into account that the liquid from the drinking vessel 64 , 66 does not enter the body of the patient 10 but is poured out or dumped out. The image evaluation unit can also detect this event and determine approximately the amount of liquid poured out from the movement of the drinking vessel 64 , 66 .

[0136] Reference numerals list

[0137]

[0138]

[0139]

Claims

1. A method for automatically balancing fluids for a patient (10) using a system (20), wherein the system (20) comprises - bed scale (32), - a reading unit (72) having at least one reading device (74), - a camera unit (76) having at least one camera (78), - a list of objects (70) in a computer-evaluable form, and - a signal processing unit (22), wherein in order to care for the patient (10), - Use the bed (30), and - using or being able to use at least one movable object (60), wherein the used or usable object or at least one, preferably each used or usable object (60) is provided with a machine-readable identifier (62) which distinguishes the object (60) from the other used object or each other used object (60), Wherein for each object (60) used, the object list (70) includes - its identifier (62) and - information about the weight and / or about the amount of liquid that the object (60) can accommodate, where a reference time period is predetermined for the fluid balance, wherein the or each reading device (74) has a reading area and the bed (30) is located in the reading area at least during a reference time period, wherein the camera or each camera (78) has a field of view and the bed (30) is located in the field of view at least during a reference time period, The method is performed at least within a reference time period and comprises the following steps: a bed scale (32) measuring the respective current weight [Gew(30)] of the bed (30) at least at a first point in time and at a subsequent second point in time, wherein two time points are within the reference time period, and wherein the patient (10) is located on the bed (30) both at a first point in time and at a second point in time, - the signal processing unit (22) derives the weight difference using the signal of the bed scale (32), wherein the weight difference is the difference between the weight of the patient (10) at the second time point [Gew(30)] and the weight of the patient (10) at the first time point [Gew(30)], - the reading unit (72) reads a corresponding identifier (62) of at least one object (60), - the camera unit (76) generates at least one image [Abb (60)], preferably a sequence of images, - the signal processing unit (22) detects each object (60) that has come into the vicinity of the patient (10) and / or has been removed from the vicinity of the patient (10) within a reference time period, wherein the step of detecting the object or each object (60) is performed using at least one signal [Read(62)] of the reading unit (72) and / or using at least one signal [Abb(60)] of the camera unit (76), and - the signal processing unit (22) calculates the fluid balance of the patient (10), wherein the fluid balance is the difference between the amount of fluid that has been delivered to the patient (10) in total during a reference time period and the amount of fluid that has left the patient (10) in total during a reference time period, To calculate the fluid balance, use - the or each derived weight difference of the bed (30), - information about which objects (60) have arrived in the vicinity of the bed (30) and have been detected, - information on which objects (60) have been removed from the vicinity of the bed (30) and detected, and - Information about the weight and / or amount of liquid contained in the object list ( 70 ) for these objects ( 60 ).

2. The method according to claim 1, characterized in that: The method comprises the additional steps of: - the bed scale (32) measures the current weight [Gew(30)] of the bed (30) at least once, preferably repeatedly, within a time interval between a first point in time and a second point in time, and The signal processing unit (22) determines the time course of the weight of the bed (30) [Gew(30)] within the time interval and uses the time course when calculating the liquid balance.

3. The method according to claim 1 or claim 2, characterized in that: The method comprises the additional steps of: The bed scale (32) measures the current weight [Gew(30)] of the bed (30) at a third time point between the first time point and the second time point, The signal processing unit (22) checks whether the patient (10) is outside the bed (30) at a third point in time, and If the patient (10) is outside the bed (30) at a third time point, the signal processing unit (22) - using said first time point as a departure time point and using said second time point as a subsequent return time point, - determining the difference between the measured weight of the bed (30) at the return time and the measured weight of the bed (30) at the departure time as the difference between the amount of liquid that has been delivered to the patient (10) outside the bed (30) and the amount of liquid that has voluntarily left the patient (10) outside the bed (30), and The determined weight difference is used for calculating the liquid balance.

4. The method according to any one of the preceding claims, characterized in that The system (20) includes a volume flow sensor (80), and The method comprises the additional steps of: the volume flow sensor (80) measures the volume flow or mass flow of the liquid entering into the body of the patient (10) and / or exiting from the body of the patient (10) through the fluid guiding unit (56), and - the signal processing unit (22) uses the measured volume flow or mass flow when calculating the liquid balance, Two additional steps - at least within the time interval between the first point in time and the second point in time, and - is performed when the patient's body (10) is connected to the fluid guiding unit (56).

5. The method according to any one of the preceding claims, characterized in that The system (20) includes a urine bag scale (52), and The method comprises the additional steps of: - the urine bag scale (52) repeatedly weighs the weight of the urine bag (50) within a time interval between a first time point and a second time point, wherein the urine bag (50) is at least temporarily connected to the body of the patient (10) during the time interval, and The signal processing unit (22) determines the time profile of the measured weight of the urine bag (50) within the time interval and uses the determined time profile in calculating the fluid balance.

6. The method according to any one of the preceding claims, characterized in that The system (20) includes a table scale (42), and The method comprises the additional steps of: - the table scale (42) repeatedly weighs the weight of the table (40) within a time interval between a first time point and a second time point, wherein objects used or usable for caring for the patient (10) are stored or can be stored on the table (40), and The signal processing unit (22) determines the time course of the measured weight of the table (40) within the time interval and uses the time course when calculating the liquid balance.

7. The method according to any one of the preceding claims, characterized in that The reading unit (72) comprises at least two reading devices (74) and / or the camera unit (76) comprises at least two cameras (78), The step of detecting each object (60) by the signal processing unit (22) comprises the following steps: - the signal processing unit (22) determines the position and / or movement of the object (60) relative to the bed (30) at least once, preferably repeatedly, within a reference time period, For this purpose, the signal processing unit (22) uses the signal of the or each reading device (74) and / or the or each camera (78), respectively, and The signal processing unit (22) determines the time course of the position and / or the movement within the time interval and uses the time course to calculate the fluid balance.

8. The method according to any one of the preceding claims, characterized in that At least one object (64, 66) used or usable for caring for a patient (10) is a container designed to receive a drinkable liquid and to be directed to the mouth of the patient (10), The method further comprises the steps of: the signal processing unit (22) - detecting the event that the container (64, 66) is introduced to the mouth of the patient (10), - measuring how long the patient (10) drinks from the container (64, 66), - determining an approximate amount of liquid consumed by the patient (10) from the container (64, 66), and - using said approximation for calculating said fluid balance, The signal processing unit (22) uses at least one signal from the reading unit (72) and / or at least one signal from the camera unit (76) and the object list for detection and for determination.

9. The method according to any one of the preceding claims, characterized in that The articles (34, 36, 38) used for caring for the patient (10) are designed to - arranged at or under the body of the patient (10) at least when the patient (10) is lying on the bed (30), and - receiving fluids excreted by the patient (10), The method further comprises the steps of: the signal processing unit (22) - determining the weight of the bed (30) at an earlier point in time [Gew(30)] and the weight of the bed (30) at a later point in time [Gew(30)], Both time points are within a pre-given reference time period. wherein the patient (10) is either on the bed (30) at two points in time or outside the bed (30) at two points in time, and wherein the weight is determined using a signal from a bed scale (32), and - calculate the difference between these two weights, and - Using the calculated difference for calculating the fluid balance.

10. The method according to claim 9, characterized in that The method comprises the following further steps: the signal processing unit (22) - detecting an event in which an object (34, 36, 38) at or under the patient's body (10) is replaced, To this end, the signal processing unit (22) uses the reading device (74) or the signal of the reading device (74) [Read (62)] and / or the camera (78) or the signal of the camera (78) [Abb (60)], and - Using the time point before the object is replaced as the earlier time point, and using the time point after the replacement as the later time point.

11. The method according to claim 9 or claim 10, characterized in that The article used is designed to remain on the bed (30) even when the patient (10) is not located on the bed (30), and The signal processing unit (22) - using a time point at which the patient (10) was not in the bed (30) as an earlier time point, and - Using another time point at which the patient ( 10 ) is also not located on the bed ( 30 ) as a later time point.

12. A system for automatic fluid balancing for a patient (10), wherein the system (20) is designed to be used in a situation in which, for the care of the patient (10), - Use the bed (30), and - using or being able to use at least one movable object (60), wherein the used or usable object or at least one, preferably each used or usable object (60) is provided with a machine-readable identifier (62) which distinguishes the object (60) from the other used object or each other used object (60), The system (20) comprises - bed scale (32), - a reading unit (72) having at least one reading device (74), - a camera unit (76) having at least one camera (78), - a list of objects (70) in a computer-evaluable form, and - a signal processing unit (22), Wherein for each object (60) used, the object list (70) includes - its identifier (62) and - information about the weight and / or about the amount of liquid that the object (60) can accommodate, wherein a reference time period is predetermined for the fluid balance, wherein the or each reading device (74) has a reading area and the bed (30) is located in the reading area at least during a reference time period, wherein the camera or each camera (78) has a field of view and the bed (30) is located in the field of view at least during a reference time period, wherein the bed scale (32) is designed to measure the current weight [Gew (30)] of the bed (30) at least twice within a reference time period, wherein the reading unit (72) is designed to read a corresponding identifier (62) of the object (60), wherein the camera unit (76) is designed to generate at least one image [Abb (60)], preferably a sequence of images, The signal processing unit (22) is designed to detect a first time point and a second time point, The two time points are both within the reference time period, the bed scale (32) measures the current weight of the bed at the two time points respectively, and the patient (10) is already on the bed (30) at the two time points, wherein the signal processing unit (22) is designed to derive a weight difference using the signal of the bed scale (32), wherein the weight difference is the difference between the weight of the patient (10) at the second time point [Gew(30)] and the weight of the patient (10) at the first time point [Gew(30)], wherein the signal processing unit (22) is designed to detect each object (60) that arrives in the vicinity of the patient (10) and / or is removed from the vicinity of the patient (10) within a time interval from a first point in time to a second point in time, wherein the signal processing unit (22) is designed to perform the detection using at least one signal [Read (62)] of the reading unit (72) and using at least one signal [Abb (60)] of the camera unit (76), wherein the signal processing unit (22) is designed to calculate the fluid balance for the patient (10), and The signal processing unit (22) is designed to calculate the liquid balance using - the or each derived weight difference of the bed (30), - information about which objects (60) have arrived in the vicinity of the bed (30), - information about which objects (60) have been removed from the vicinity of the bed (30), and - Information about the weight and / or amount of liquid contained in the object list (70) for these objects.

13. The system according to claim 12, characterized in that The bed scale (32) is designed to measure the current weight [Gew(30)] of the bed (30) at a third time point, wherein the third time point is between the first time point and the second time point, and The signal processing unit (22) is designed to check whether the patient (10) is outside the bed (30) at a third point in time. The signal processing unit (22) is designed to, when the patient (10) is outside the bed (30) at a third time point, using the first time point as a departure time point and using the second time point as a subsequent return time point, determining the difference between the measured weight of the bed (30) at the return time and the measured weight of the bed (30) at the departure time as the difference between the amount of liquid that has been delivered to the patient (10) outside the bed (30) and the amount of liquid that has voluntarily left the patient (10) outside the bed (30), and The determined weight difference is used for calculating the liquid balance.

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