Apparatus for detecting movement exiting a bed or a folding bed or the like . and system for detecting and indicating the exit from beds comprising said apparatus .

The present invention relates to an apparatus for detecting movement exiting a bed or a folding bed or the like comprising means for detecting patient exit movement and indicating means and at least a support surface, such as a mattress or the like.

Apparatuses of this type are known and widely used. While these apparatuses satisfactorily serve their function, they have some drawbacks.

Current apparatuses used for detecting the patient movement exiting a bed or a folding bed or the like, provides to use movement detection means around the perimeter of the support region of said bed. Said detection means are placed at such an height with respect to the support region to detect any movement of the patient exiting out of the perimeter of said support region or raising movements over a certain height from the support surface and particularly, also natural movements when sleeping. Thus the apparatus produces numerous false alarms detecting all patient movements, without distinguishing natural movements, for example with the patient sleeping, and movements caused by an exit attempt.

Such false alarms cause the apparatus not to be so much useful since the staff is obliged to make very frequent monitoring interventions thus making the work impracticable and impossible to carry on. In order to avoid numerous false alarms said detection means are placed at such an height with respect to the support region not to detect all natural patient movements. However, in this case, the patient exit cannot be noticed when the patient falls out of bed or folding bed without interfering with the detection beam of movement detection means and so without activating the alarm signal since movement detection means have detected no body passage.

To this aim an attempt to overcome this drawback has been made by providing various sensing elements associated to a logic interpreting signals received from such sensing elements.

Among other things a suggested solution provides to use different kind of sensing elements, such as for example light barriers associated to weight sensing elements placed at the bed support surface.

These solutions are complex, expensive and however they solve only partially the above problems, so they have not helped to allow the use of automatic apparatuses indicating the patient exit from a bed.

It is to be noted that such problem exists since both in the case of elderly patients or very young patients, namely children, and patients of any age subjected to an operation and so to a general anaesthesia, when they wake up a half-consciousness

state can occur leading the patient to try to move even when he cannot move or to move according to movements and paths known in the usual life domestic surroundings that do not correspond to the real situation he is in. Anyhow these situations are very dangerous for the patient safety and so they have to be avoided. The solution must consider the fact that the patient have to be respected to a certain extent and so drastic measures restricting the patient freedom cannot be taken deeply contributing to increase the awakening shock.

Aim of the present invention is to provide an apparatus for detecting movement exiting a bed or a folding bed or the like able to overcome in a simple and inexpensive way the drawbacks of known bed exit detection apparatuses, allowing to moderately indicate such an action and by a low impact of false alarms and by using inexpensive and simple apparatuses .

The invention achieves the above aims by providing an apparatus for detecting movement exiting a bed or a folding bed or the like comprising means for detecting the exit movement of a patient and indicating means and at least a support surface, for example a mattress or the like and wherein means defining a fixed path for exiting the bed or the folding bed are associated to the bed or folding bed detection means being placed or adjusted or oriented such to detect a body passage only along said fixed exit path or along at least a part thereof. A preferred example of means for defining a fixed

path is the fact that on at least one peripheral edge, preferably along at least the two longitudinal side edges especially around all the perimetral edge of said support surface, there are barrier preventing the normal exit movement defining an overpassing plane with a predetermined minimum height with respect to the support surface such that said preventing barriers force to make a movement overpassing them.

Advantageously the invention comprises a bed having around all the perimeter of the support surface barriers preventing the normal exit movement.

Said preventing barriers can be movable and have a predetermined minimum height that is adjusted such to force the patient to make a fixed exit path. Said fixed exit path is defined such that it requires a passage time higher than a predetermined time range, a relatively long time and higher than a casual passage time of a limb during a natural movement. Said predetermined time range is from 1 to 10 seconds, preferably lower than 10 seconds, particularly between 4 and 6 seconds .

Detection means are placed at a predetermined positioning height, said predetermined positioning height being adjusted such that patient natural movements are within and below a lower limit of the detection range of the detection means that is a function of said predetermined positioning height, while the passage of the body in the fixed path is defected said path being such that it reaches or comprises or passes through a level coinciding or

interefering with the detection range or with a part thereof and being higher than said lower minimum level delimiting the detection range.

Said detection means can be any type of sensing elements intended to detect the passage of a human body or a part thereof and particularly they are proximity sensing elemets and/or infrared sensing elements and/or ultrasound sensing elements. Said sensing elements comprise a receiving unit and a transmitting unit. According to a further characteristic the apparatus can comprise various different sensing elements that is intended to detect different conditions or different effects. An example provides the element covering the bed support surface, at the pillow, to have at least a weight sensing element under it such that the personal staff is aware of each time the patient rises the head.

With reference to means indicating the detected exit movement these can be of any type and for example they are of the acoustic and/or visual type.

Said indicating means can be local ones i.e. separately associated to each bed to which a corresponding apparatus is associated and controlled by the apparatus of the corresponding bed. When there are provided two or more beds each bed can be provided in combination with a dedicated apparatus for detecting and indicating the exit movement therefrom. In this case, said indicating means aaςe in common to two or more apparatuses of two or more beds.

A variant of the above condition provides said indicating means to be centralized and to be provided with a line communicating with a central indicating unit via cable and/or wireless. As an alternative or in combination said centralized indicating means and/or apparatuses are provided with means for communicating with one or more personal indication receivers such as mobile phones, transceivers via radio wave. Still with various apparatuses each one associated to a different bed, said apparatuses are provided with an identification code each, said identification code being joined to the indication command and said identification code being displayed and/or noticed to the hospital staff for identifying the bed from which it comes from.

In an advantageous embodiment said centralized indication unit comprises an interactive plan displayed on a screen where the bed corresponding to the identification code of the apparatus emitting the alarm is visually highlighted.

The present invention relates also to a system for detecting movement exiting one or more beds or a folding bed or more folding beds or the like, provided in an hospital room or in an hospital or a rest home for elderly people or the like. Said system comprises exit detection apparatus associated to each bed and a centralized unit emitting an alarm that is directly anjd/or indirectly connected to at least a part or all apparatuses .

Said apparatuses are connected to the centralized unit emitting the alarm by one or more collecting elements.

Said collecting elements are intermediate receiving and transmitting units receiving the signal from a subgroup of apparatuses and communicate with a centralized unit by a single line.

At least one of the elements among the apparatus, collecting elements, alarm emitting centralized unit houses a software and/or a firmware for processing acquired signals.

An embodiment of said system for detecting the exit movement is composed of an alarm emitting centralized unit comprising: • At least a processing unit

• At least a displaying means, for example a monitor or the like

• At least a data inputting means, for example a keyboard, touch screen or the like • At least an acoustic and/or visual indicating means and/or the like

• At least one or more data transmitting/receiving systems.

Said centralized unit processes signals coming from the exit detection apparatuses and makes them available to the user by said indicating means.

Said centralized unit silences and/or resets the occurred alarm by said data inputting means and/or said data transmitting/receiving means.

Further improvements of the invention are object of subclaims.

These and other characteristics of the present invention and advantages deriving therefrom will be more clear from the following description of some embodiments shown in annexed drawings wherein:

Fig.l is a side view taken longitudinally or from the longest side of an embodiment of the apparatus object of the present invention. Fig.2 is a side view taken from the transverse or shortest side of an embodiment of apparatus object the present invention.

Fig.3 is a perspective view of an embodiment of the apparatus object of the present invention wherein like previous figures 1 and 2, sensing elements cover a space volume extending over the supporting surface, that is the bed mattress for all the area thereof and between two height levels an upper one and a lower one the upper level being above or substantially coinciding with the level of peripherical barriers.

Fig.4 is a prespective view similar to figure 3 wherein sensing elements are provided only at space volume above the upper level defined by the longitudinal side barriers, while in the intermediate region no detection occurs.

Fig.5 is a side view like fig.l taken on the longitudinal side of an embodiment of the apparatus object of the present invention with the patient shown wejLght sensing elements being also provided and the patient being in a not completley lay down position

with his knees risen and his arms somewhat risen.

Pig.6 is the view of fig. 5 wherein there is provided also a block diagram of a variant embodiment of the invention. Pig.7 is a simplified block diagram of a system according to the present invention comprising various apparatuses according to previous figures each one associated to one or more beds of two rooms centralized monitoring and controlling means and indicating mobile means being provided.

In fig. 1 and 2 there is shown an embodiment of the apparatus object of the present invention by way of example and it is not a limitative one.

The apparatus aims at detecting movements or attempts exiting an hospital bed, indicating the hospital staff that such an action occurred or is occurring made by a patient and possibly indicating which patient and/or at which bed such action occurred or is occurring. The apparatus according to the present invention provides to associate to each bed means for defining a fixed exit path which path coincides with the range of at least a sensing element and which sensing element works exclusively in said range interfering with said exit path or with a part thereof.

Due to the above the fixed exit path can be selected such not to interfere with possible paths unintentionally followed by a patient when sleeping and wh^ch can be detected as exit attempts. In the shown embodiment the choice of means for

defining the fixed exit path are composed of exit preventing barriers 3 that are arranged or better shaped in a predetermined way as it will be described below in more details. Each bed 1 comprises a frame with a patient support surface 2 defined for example by the top of a mattress or the like. Along the perimetral edge of the bed and so around the support surface 2 and particularly along longitudinal edges, since the bed generally has two upward bedboards, there are provided barriers 3 preventing the normal exit movement. Said preventing barriers 3 in the form of side bars or rails prevent the normal exit movement and define an overpassing path running above an overpassing plane or level with a minimum predetermined height h that is higher than the level of the support surface 2. Thus preventing barriers 3 define a path for exiting the bed forcing the patient to make a movement overpassing them obligatorily passing above said rails. In order to detect the passage of a body or a part thereof along the path overpassing preventing barriers 3, detection means 4 are provided placed and/or adjusted and/or oriented such that the detection range thereof coincide only with said overpassing path or with a part thereof. Particularly said detection means are placed, oriented or adjusted such that their detection range has a lower limit that is said level h of rails above the support surface or a level higher thj.n it for a certain predetermined extent. According to said embodiment said detection means

are placed at a predetermined positioning height H; said predetermined positioning height H is determined such that the detection range extends to such a level/ above the bed support surface 2, that patient natural movements are below the lower limit of said detection range and/or of said predetermined positioning height H/ while as said above the detection range of said detection means coincide with the path overpassing barriers or with a part thereof. In one embodiment detection means 4 are placed along the two bedboards of the bed 10 applied directly to them or by means of brackets or other supporting means 110 particularly allowing to adjust the position and/or orientation, especially as regards the positioning height H and orientation of sensing elements.

Depending on the kind of sensing elements used these have a certain detection range that can be defined by an ideal detection volume such as indicated by broken lines by V and V , V ' in figures 3 and 4 that will be described below in more details.

The arrangement, and amount of detection sensing elements or means depends on the size and arrangement or position of the space volume within which the presence of a body or a part thereof is to be detected. So for example such as shown in figure 2, various sensing elements 10 are mounted side by side along an axis parallel to the support surface 2 and to bedboards 10 of the bed in order to cover a detection volume V substantially or approximately having the shape of a rectangular parallelepiped having a lower delimiting

plane provided above the support surface 2 flush with the upper limit of barriers 3 or also at a higher level .

Therefore, with reference to figure 3, the detection range is composed of a space volume V delimited on the lower side by the plane parallel to the support surface 2 and denoted by 204 and on the upper side by an upper plane parallel to the support surface 2 as well and it is denoted by 304. The width is substantially equal to or preferably slightly greater than the width of the support surface 2 or better to say than the transverse spacing between preventing barriers 3 along the two faced longitudinal sides of the bed. Detection sensing elements 4 having a predetermined emitting/receiving spread are placed at the predetermined positioning height H and have such an orientation that the shown detection range is determined by the combination of height H, orientation and transmitting/receiving spread. Obviously, the lower and/or upper and/or also side surfaces delimiting the detection range can be also not flat ones, so the space volume equivalent to the detection range can have an ideal shape also different with respect to the rectangular parallelepiped one and it can be also a completely uneven shape. The alignement plane of emission receiving and/or propagation axes of detection signals is denoted by 104. Obviously ideal boundaries of volume V are like a parallelepiped only as an indication since the particular shape will be a different one and it will substantially depend on the

spread cone of sensing elements and of detection means. However the use of a parallelpiped shape makes the concept more clear. The shape and position of the ideal surface delimiting the volume within which detection means 4 are operating in order to recognize and indicate the presence of a body or a part thereof depend on the arrangement of sensing elements 4, on the amount and characteristics thereof.

Thus for example if a detection of possible i passages of a body part also outside longitudinal sides of the bed it desired it is possible to provide detection means composed of an array of two or more sensing elements or only one sensing element even along bed sides. Particularly an embodiment is shown by broken lines in figure 2 wherein arrays 404 of various sensing elements 4 are provided outside the two longitudinal vertical sides of the bed 1, sensing elements 4 being placed side by side along a vertical axis. Figure 4 is a further variant for arranging detection means 4, whose advantages will be more clear from the following description. In this case each bedboard bears a pair of individual sensing elements 4 or arrays 404' , 404' ' of sensing elements 4 respectively provided at each corner region of the bed 1 and are connected at emitter/receiver pairs or however in such a way to generate two detection volumes V and V ' extending with their lower delimiting plane 2QJ flush with the height h of the upper edge of the barrier 3 composed of the lateral longitudinal rail or

at a higher height, the lower delimiting plane 204 being parallel to the support surface 2 and whose width extension, i.e. the extension in the transverse direction of the bed is such to be restricted to a thin peripherical inner and outer band that is directly- adjacent to the vertical plane subtended by the rail or barrier 3 or by the longitudinal side of the bed. In this case, therefore in the volume above the support surface 2 and intermediate between the two ideal detection volumes V , V ' the presence of a body or a part thereof is not detected, so possible patient movements for rising limbs cannot lead to a false alarm indication about an exit attempt.

Obvisouly shown width dimensions of detection volumes V , V ' are merely by way of example and are not limitative ones.

Fig.5 shows an embodiment of the apparatus with a patient P. Said patient P is lay down on the support surface 2 i.e. on the mattress with the head on a pillow 5 and with knees in the bent condition. Detection means 4 or arrays 404 of detection means are placed at a predetermined positioning height H adjusted such that natural movements of the patient P remain within and below the lower limit 204 of the detection range defined by the volume V within which detection means 4 are operating.

As it results from figure 5, the lower limit 204 of the volume within which detection means 4 are able tα_ detect the presence of a body or a part thereof of a patient P, is provided at a level Hl that is higher

than the level h of the overpassing barrier 3 to a predetermined extent. Therefore when a part of the body of the patient P is in the level band having a thickness dh and comprised between the upper level of the barrier 3 and the lower delimiting surface 204 of the space volume corresponding to the lower limit of the detection range of detection means, due to a natural movement when the patient is sleeping or half- sleeping that is a transitory movement not aiming at an aware or not aware attempt exiting the bed, so such condition does not lead to any indication, so the emission of an alarm signal is effectively avoided. Such condition is indicated in figure 5 by the fact that the patient P is in the state with his knees and arms raisen in a position higher than level h of the barrier 3 and lower than the lower delimiting plane 204 of the detection range.

Obviously the spacing dh can be changed by positioning and/or orienting detection means 4 and/or by changing the height position of the overpassing barrier 3.

However the thickness dh can be selected such that it is surely lower than the average thickness of a body when overpassing the barrier 3. Moreover, advantageously, the barrier 3 is provided with a maximum height h such that the patient is not obliged to make too dangerous movements when exiting and such that it is not considered a coercion means.

. _^ Considering these conditions, so the further improvement of the variant shown in figure 4 can be

understood. Under these conditions detection ranges composed of the two ideal volumes V and V ' are substantially restricted to the region of longitudinal barriers 3 and so the patient can essentially move in the height direction without any restrictions for a space portion coinciding with a substantial part of the volume or a space column having the support surface 2 as the base, the sensitiveness of detection means being limited to or can be limited to thin lateral bands. As an alternative or in combination with the above and as it is clear from figure 5, in combination with means 4 detecting the patient body or parts thereof along. at least a part of the fixed path overpassing the barriers 3 it is possible to provide presence sensing elements as in the form of weight sensing elements 40 for the patient or body parts thereof on the support surface 2. That further helps to verify a real dangerous situation with the patient exiting the bed. Considering the condition of figure 5 the patient P is still detected by all three shown weight sensing elements 40. If the sitting state of the patient is considered so however at least two of the three shown weight sensing elements 40 would detect the presence of the patient P. Under this condition it is possible to provide a double condition in order to begin the generation and emission of an alarm signal.

With reference to figure 6 there is shown the condition of figure 5 and by a block diagram a system generating alarm signals of the type dedicated to the single bed 1 or to a limited amount of beds one near

the other.

An interpreting logic 15 both in the form of a fixed circuit and of a small central processing unit wherein a logic interpreting software is loaded and can be executed collects signals from various sensing elements 4 and 40 and on the basis of signals received therefrom it generates or not an alarm signal.

Obviously the above is only a set of examples and it is not to be intended as limiting the inventive teaching.

With reference to above examples, each bed is provided with its own dedicated and separated apparatus and with its own dedicated and separated indicator 16. The indicator 16 that can be of any type such as an acoustic and/or light indicator can be associated to the bed. In the example of figure 6 the indicator 16 is controlled by the logic unit 15.

In combination or as an alternative/ each apparatus can comprise a transmitter 17 emitting an alarm call to a portable indication unit for example a receiver 18. The latter can be a unit dedicated and specifically made for the apparatus, or it can be a telephone unit, such as a mobile phone or a device known as beeper. A portable unit receiving the signal warning can be contemporaneously used for various detection apparatuses of various separated beds. In this case, therefore, it is important for each detection apparatus to _* , be provided with an identification code of the bed allowing to accurately find the location of the

apparatus and so the bed from which the warning indicating the patient exiting condition comes from.

For example such as shown in figure 6, the processing unit 15 can provide a memory 115 wherein an identification code can be stored that can be inserted by data input means 19, such a a keyboard or the like.

As it will be seen in the following description as an alternative the signal warning the patient exit emitted by each apparatus is sent to ta remote station that in turn provides to sort warnings to one of a plurality of hospital persons according to a list assigning patients to specific hospital persons and/or to reports made by hospital persons regarding their availibility condition or readiness in intervening. Figure 7 is an embodiment of a system object of the present invention and having a managing unit 20. The system comprises a plurality of beds 1 a detection and indicating apparatus is associated to each one of such beds as the one according to one or more different embodiment variants described above for the single bed. Particularly, in the example of figure 7 there is shown a connection of beds 1 that is of sensing elements associated thereto by lines via cable to the remote processing unit 20. However it is also possible for signals from sensing elements 4, 40 to be transmitted via radio or the like by providing a transmitting unit associated to sensing elements 4, 40 of each bed 1 or it is also possible for each bed or. subgroup of beds 1 tα_ provide a dedicated local station made according to what described with reference to figure 6, which

communicates with the remote unit 20 via cable or via radio. In this case the communication with a portable unit can occur directly from the local station or by the remot central station 20 or from both of them according to a concurrent starting protocol wherein a station is the hot spare of the other one. Therefore, with reference to the specific example shown, each bed 1 has at least a type of detection means 4 and one or more preventing barriers 3 according to what already described above and object of the present invention.

Outputs from indvidual sensing elements 4, 40 and of further possible detection means or of one local processing unit 15 are connected to the remote central unit 20 by collecting elements 9 and communication lines.

According to a preferred shown example the remote station 20 in addition to manage alarms and warnings by means of centralized means 16 or by means of the communication via radio to mobile units 18 by a transmitter 17, it can read the identification code of the bed 1 from which signals of detection means 4, 40 have generated an alarm condition and can display the location of said bed 1 in a shematic virtual plan displayed on a monitor 22. Due to the fact that it has a suitable small screen the image of the central monitor 22 can be sent for example as a multimedia message so called MMS to the mobile unit 18 and can be displayed on the screen 118 thereof. To this aim the central unit 20 comprises a CPU intended to execute a managing program allowing to receive signals of

detection means 4, 40 or from local units 15 of individual beds, to determine beds 1 to which received signals refere to and to associate a predetermined geographical location of the bed, to verify the presence of a signal that can be interpreted as an action exiting the bed and to generate an alarm signal as well as to send said signal to a portable remote unit and/or to emit it at indicating means directly associated to the central unit 20. An embodiment variant can advantageously provides the apparatus of each bed to be made as in figure 5 and to comprise a local intelligence part as a local processing unit 15 therefore providing signals already interpreted and identification codes about the station location to the central unit 20.

For the above functions, the central unit 20 comprises a memory wherein a managing program is loaded that for example generates a graphical representation of rooms and beds provided and it displays the bed whose position in the graphical representation corresponds to bed 1 whose apparatus has generated the warning. Moreover said central unit has a memory with a program managing the emission of warning signals via radio sent to a plurality of portable receiving remote units 18 and possible also a program verifying the availability or intervention readiness of the hospital person managing a portable unit .

In the example of figure 7, there are shown beds 1 provided in an hospital facility in two rooms Cl, C2 with .4 and 8 beds respectively. As said above, by means

of the identification code associated to signals of detection means 4, 40, the central unit determines the bed 1 and its geographical location with reference to a plan reproducing the geographical condition of rooms Cl and C ' and wherein beds in individual locations are shown. To each location corresponds an identification code and therefore on the monitor 22 an image of rooms comprising images of room ICl and IC2 and images of beds 1 is generated. When signals of detection means are read such that an alarm signal occurs, so the identification code sent together with said signals to the remote central processing unit 20 is read and the geographical location of the bed position emitting the alarm warning is determined. In the figure this location is highlighted in grey and the bed is denoted by 1' . In image ICl and IC2 therefore the location in the plan of the bed 1" from which the alarm comes from is highlighted with a color or a higher or different intensity and in figure 7 it is indicated as ICl' . Images of other beds are denoted as ICl.

When, as it is shown, there are provided portable units 18 provided with a screen images ICl and IC2 can be sent also to the unit 18 and can be displayed by it thus making the action of hospital staff more simple intuitive and fast.

Other functions can be implemented via software in the system according to the present invention that as this variant allow to manage the staff in a very simple and rational way and allow to better organize the work, as well as more rapid interventions and so a greater

safety of the patient.

It is to be noted that possibly the distance of the intervention site from the staff managing a local portable unit can be verified and so it is possible to send the warning to the hospital person closer to the bed where the emergency condition has occurred.

In this case the managing program can also provide a list of persons in charge of the monitoring operation and which must answer to the alarm and to which persons a list of identification codes about the locations of beds 1 in charge of the person can be assigned. Thus once the code of the bed location has been identified, the central unit 20 transmits a message only to the mobile unit 18 of the person in charge of the specific bed location that has generated the alarm. It is also possible to provide a list of persons that have to be automatically advised as a second choice if for example the person in charge of a bed location is temporarily idle or if is working with another patient and sends a signal about the non intervention to the central unit or if the central unit has just sent an alarm signal to the same person from another location.

Due to the above advantages of the system are clear allowing a management that is rational, inexpensive and easily to improve.