JP7816973B2 - Monitoring system - Google Patents

Description

This disclosure relates to a monitoring system that can be installed in a nurse call system and monitors patients.

Technology has been developed in hospitals, nursing homes, and other facilities to monitor patients' movements by installing cameras around beds. For example, Patent Document 1 introduces a nurse call system that constantly films patients, analyzes the footage, and accurately detects when the patient gets out of bed.

Japanese Patent Application Laid-Open No. 2019-063542

By the way, video footage of patients is stored on a nurse call server and remains in the database even after the patient has recovered and been discharged from the hospital. From the perspective of protecting the patient's privacy, it is preferable to automatically delete such footage at an appropriate time. However, simply deleting all footage poses a problem: if an accident were to occur, such as a patient falling or tipping out of bed, it would be impossible to determine the cause of the accident.

The purpose of this disclosure is to provide a monitoring system that can automatically delete unnecessary footage while retaining footage necessary for investigating the cause of an accident.

To solve the above problem, the monitoring system disclosed herein comprises a camera that captures images of the patient around the bed, a recording means for recording the camera's images, an image erasure means that automatically erases the images after a predetermined storage period has elapsed since they were captured, a condition detection means that detects a predetermined condition of the patient based on the recorded images, and an accident determination means that determines whether an accident has occurred based on the condition and sets a predetermined period including the time the accident occurred as an erasure prohibition period, and the image erasure means is characterized in that it does not erase images captured during the erasure prohibition period.

The monitoring system disclosed herein sets a specific period of time, including the time the accident occurred, as a deletion prohibition period, during which other video footage is deleted. This has the effect of preserving the video necessary to investigate the cause of the accident while automatically deleting other video footage, thereby protecting the patient's privacy.

1 is a system diagram of a nurse call system illustrating one embodiment of the present disclosure. FIG. 1 is a block diagram showing the configuration of a nurse call system. FIG. 10 is a schematic diagram showing the positional relationship between a camera and a bed. FIG. 10 is an explanatory diagram showing a storage period. FIG. 10 is an explanatory diagram showing variations of erasure prohibition periods. 10 is a flowchart showing a flow of setting an erasure prohibition period.

An embodiment of the monitoring system disclosed herein, embodied in a nurse call system, is described below with reference to the drawings. As shown in FIG. 1, the nurse call system 1 of this embodiment comprises a nurse call base unit 6 installed in a nurse's station, a mobile terminal 10 (such as a PHS or smartphone) carried by a nurse, a controller 7 installed in a management room or other location, a relay device 9 (such as an IP-PBX) installed in a server room or other location, base stations 8 located throughout the hospital, a hallway light 4 installed in a hallway, a nurse call handset 5 installed near a patient's bed 51, a camera 3 installed near the patient's bed 51, and a nurse call server 2 that provides information related to the nurse call system 1. The relay device 9, controller 7, hallway light 4, nurse call base unit 6, and nurse call server 2 are connected via a LAN line L1. The nurse call handset 51 is connected to the hallway light 4 via transmission line L2. The camera 3 is connected to the hallway light 4 via transmission line L3. Note that the relay device 9, base station 8, and mobile terminal 10 are omitted from Figure 2.

As shown in FIG. 2, the nurse call server 2 includes a CPU 21 that controls the nurse call server 2, a recording unit 22 that records the video 12 from the camera 3 (see FIG. 4), a video erasure unit 23 that automatically erases the video 12 after the retention period Pk has elapsed since capture, a status detection unit 24 that detects a predetermined state ST of the patient 52 based on the recorded video 12, an accident determination unit 25 that determines whether or not an accident has occurred based on the state ST and sets a predetermined period including the time Ta at which the accident occurred as the deletion prohibition period Pf, the video erasure unit 23 that automatically erases the video 12 after the retention period Pk has elapsed since capture, and a setting unit 26 that sets the unit time Pu for the deletion prohibition period Pf. The recording unit 22, status detection unit 24, accident determination unit 25, video erasure unit 23, and setting unit 26 can also be provided in each corridor light 4, nurse call master unit 6, etc., as appropriate.

As shown in Figure 3, the camera 3 constantly captures the patient 52 being monitored. The captured video 12 is transmitted to the nurse call server 2 via the transmission line L3 and LAN line L1 and stored in the recording unit 22. The state detection unit 24 analyzes the recorded video 12 and detects a predetermined state ST.

For video analysis, known video analysis techniques can be used, such as SIFT (Scale Invariant Feature Transform) and SURF (Speeded-Up Robust Features). Furthermore, the positional relationship between the bed 51 and the head of the patient 52 can be used in video analysis. For example, a bed-out state ST4 can be detected when the head of the patient 52 is not included in area A where the bed 51 is located, and a fall state ST7 can be detected when the height h of the patient 52's head is lower than the height of the bed 51. It is also possible to detect a fall state ST7 when the patient moves from a lying state ST1 to a bed-out state ST4 without passing through a sitting-up state ST2. Table 1 shows examples of states ST.

In Table 1, the recumbent state ST1 indicates a state in which the patient 52 is lying on the bed 51, the sitting state ST2 indicates a state in which the patient 52 is sitting upright on the bed 51, the edge-sitting state ST3 indicates a state in which the patient 52 is sitting on the edge of the bed 51, the out-of-bed state ST4 indicates a state in which the patient 52 has left the bed 51, the standing state ST5 indicates a state in which the patient 52 has stood up, the fallen state ST06 indicates a state in which the patient 52 is lying on the floor, and the falling state ST7 indicates a state in which the patient 52 has fallen off the bed 51.

The accident determination unit 25 determines that no accident has occurred (Off) in the cases of ST1 to ST5, and determines that an accident has occurred (On) in the cases of states ST6 and ST7. The accident determination unit 25 sets a predetermined period including the time when the state ST linked to the occurrence of the accident was detected (accident occurrence time Ta) as the erasure prohibition period Pf. As an example of setting the erasure prohibition period Pf, it is possible to select a method in which the recording unit 22 stores the erasure prohibition period Pf by linking it to the video 12 in which an accident has been determined.

As shown in Figure 4, the video erasure unit 23 erases video 12 recorded in the recording unit 22 for which the storage period Pk has elapsed since the shooting time Tp. The storage period Pk can be set arbitrarily, but is generally preferably about 30 days. When a deletion prohibition period Pf is associated with video 12 for which the storage period Pk has expired, the video erasure unit 23 does not delete the video 12 shot during the deletion prohibition period Pf, but leaves it stored.

As shown in Figure 5(a), the erasure prohibition period Pf can have a start time Pf1 of the time when the out-of-bed state ST4 is detected and an end time Pf2 of the accident occurrence time Ta. Alternatively, as shown in Figure 5(b), the start time Pf1 can be the time when the edge-sitting state ST3 is detected and an end time Pf2 of the accident occurrence time Ta. Furthermore, if the accident is linked to a fall, the start time Pf1 can also be the time when the most recent recumbent state ST1 is detected. In this case, a predetermined additional period (not shown) can be set before the start time Pf1 and after the end time Pf2 to record more details about the accident.

As shown in Figure 5(c), the deletion prohibition period Pf can have an end Pf2 at the accident occurrence time Ta and a start Pf1 at an arbitrary unit time Pu retroactive to the end Pf2. The unit time Pu can be set in advance, for example, using the setting unit 26 of the nurse call server 2.

Next, the process for setting the deletion prohibition period Pf in the nurse call system 1 configured as described above will be explained with reference to Figure 6. First, when the camera 3 captures video 12 of the patient 52 (S1), the video 12 is sent to the nurse call server 2 and recorded by the recording unit 22 (S2). The state detection unit 24 analyzes the recorded video 12 (S3) and detects a predetermined state ST (S4). The accident determination unit 25 determines whether an accident has occurred based on the state ST (S5). If it is determined that no accident has occurred (S6: No), the process ends. If it is determined that an accident has occurred (S6: Yes), the deletion prohibition period Pf is set (S7), and the process ends.

The nurse call system 1 described above detects a predetermined state ST of the patient 52 based on the recorded video 12, determines whether an accident has occurred based on the state ST, and, if an accident occurs, sets the period including the time Ta of the accident as the deletion prohibition period Pf. While deleting video 12 after the retention period Pk has elapsed, the video is preserved without being deleted during the deletion prohibition period Pf. This protects the privacy of the patient 52 while preserving only the video 12 that contributes to the investigation of the cause of the accident. Furthermore, if the time when the state ST immediately prior to the accident (sitting on the edge of bed ST3, out of bed ST4) was detected is used as the start point Pf1 of the deletion prohibition period Pf, appropriate images for investigating the cause of the accident can be preserved. Furthermore, if a unit time Pu is set, the unit time Pu can be preserved retroactively from the time Ta of the accident, allowing for flexible setting of the deletion prohibition period Pf according to the patient 52's symptoms, etc.

Note that this disclosure is not limited to the above-described embodiment, and the configuration of each part can be modified as desired without departing from the spirit of this disclosure.

REFERENCE SIGNS LIST 1 Nurse call system 2 Nurse call server 3 Camera 4 Corridor light 5 Nurse call handset 6 Nurse call master 7 Controller 8 Base station 9 Relay device 10 Portable terminal 11 Monitoring system 12 Video 51 Bed 52 Patient 53 Patient's head 21 CPU
22 Recording unit 23 Video erasing unit 24 Status detection unit 25 Accident determination unit 26 Setting unit ST Status Pk Storage period Pf Erasure prohibition period (1: start, 2: end)
Pu Unit time Ta Accident occurrence time Ts State detection time L1 LAN line L2 Transmission line, transmission line

Claims (4)

a camera for photographing a patient around the bed; a recording means for recording the image of the camera; an image erasing means for automatically erasing the image after a predetermined storage period has elapsed since the image was taken; a state detecting means for detecting a predetermined state of the patient based on the recorded image; and an accident determining means for determining whether an accident has occurred based on the state and for setting a predetermined period including the time when the accident occurred as an erasure prohibition period;
the accident determination means determines the start of the erasure prohibition period to be a time when a state at least one state before the time when the accident occurred is detected,
The monitoring system is characterized in that the video erasing means does not erase the video captured during the erasure prohibition period. The state detection means detects whether the patient is out of bed,
The monitoring system according to claim 1 , wherein the erasure prohibition period is a period from the time when the bed leaving state is detected to the time when the accident occurs. The state detection means detects whether the patient is sitting on the edge of the seat,
The monitoring system according to claim 1 , wherein the erasure prohibition period is a period from the time when the sitting-on-the-edge state is detected to the time when the accident occurs. the state detection means detects a fall state when it detects a lying state of the patient and then detects a bed-getting state without detecting a sitting-up state;
The monitoring system according to claim 1 , wherein the accident determination means, when determining that an accident has occurred based on a fall state, determines that the erasure prohibition period begins when the lying state is detected.