DE10251900A1 - Patient monitoring system has sensor connection unit for parameter monitoring sensor(s), processing unit and data communications unit for transmitting signals from processing unit for evaluation - Google Patents

Abstract

The portable, mobile system has at least one sensor connection unit to which at least one sensor (30-34) for monitoring a parameter can be connected and a processing unit with which the signals produced by the sensor connection unit can be processed for transmission by a data communications unit. The data communications unit transmits the signals produced by the processing unit for evaluation.

Description

The present invention relates to a patient monitoring system. The invention further relates to a method for monitoring a patient.

There are some in the prior art approaches for remote monitoring known from vital parameters of patients. However, these are on individual parameters limited and not universally applicable and expandable.

The invention is therefore the object to avoid the disadvantages of the prior art, and especially a patient monitoring system and a method of monitoring to create or specify a patient in which one if possible efficient and flexible monitoring for one Many parameters possible is.

The aim of the present invention or the project »Mobile Medical Monitoring (MMM) «consists of the prototypical realization of a comprehensive telemedical Monitoring solution:

• - Of A portable, mobile monitoring hardware can be used in parallel Vital parameters such as EKG, SpO2, blood pressure etc. of a freely movable Patients added. They are continuously measured, pre-processed and by means of standardized mobile radio procedures (GSM / GPRS etc.) transmitted to a central receiving and evaluation station.
• - The central receiving station (a server computer) is in one Clinical service center in which the medical Incoming data, saved and visualized. It finds one immediate evaluation of all incoming data instead of when intelligent alarm algorithms a delay-free detection of critical Situations becomes. The resulting database can also be used for retrospective analyzes the stored data to generate standardized treatment guidelines (evidence based medicine) and to conduct clinical studies.

The link between these two Components of the MMM architecture represent a radio interface, with which the data is transferred from the patient to the center.

This task is done in a process of the type mentioned at the outset in that the patient monitoring system has the following:

• - one Sensor connection unit to which at least one sensor for monitoring a parameter can be connected;
• - one Processing unit through which the sensor connection unit supplied signals for transmission can be processed by the data processing unit, and
• - one Remote data transmission unit through which the transmission the signals supplied by the processing unit for evaluation same transferable is.

Further preferred embodiments of the invention are in the dependent claims disclosed.

The invention and further features Goals, advantages and possible applications the same, will be based on a description of preferred embodiments with reference to the attached Drawings closer explained. In the drawings, the same reference numerals designate the same or corresponding elements. All described and / or depicted features for themselves or in any meaningful way Combination the subject of the present invention, namely independently of their summary in the claims or their relationship. The drawings show:

1 is a schematic representation of a front view of a first embodiment of a mobile patient monitoring system according to the present invention;

2 is a schematic representation of a rear view of the first embodiment of the mobile patient monitoring system according to the present invention;

3 a schematic block diagram of a processing unit and the remote data transmission unit of the first embodiment of the patient monitoring system according to the present invention;

4 a schematic block diagram of a variant of the processing unit according to the invention;

5 is a schematic representation of the remote data transmission unit according to the first inventions embodiment according to the invention;

6 a schematic representation for explaining the operation of a second embodiment of the present invention;

7 a schematic representation of two exemplary embodiments for bus topologies (star topology or "party line" topology) which can be used together with the present invention;

8th is a schematic representation showing a star topology in connection with the present invention in further detail; and

9 is a schematic representation showing a "Party Line" topology in connection with the present invention in more detail.

Based on 1 and 2 is the basic structure of a first embodiment of a patient monitoring system 1 according to the present invention explained in more detail. Basically, the patient monitoring system according to the invention 1 from a patient whose torso 2 schematically in the 1 and 2 is shown, portable or portable or portable. In the in the 1 and 2 The exemplary embodiment shown is the monitoring system according to the invention 1 in an outer garment, and in particular in a shirt or shirt, which is preferably worn directly on the skin. Of course, deviating from the selected representation, all or some of the parts of the patient monitoring system according to the invention can be designed to be portable or portable. For example, a corresponding belt, helmet, etc. can be used. In the exemplary embodiment shown is the patient monitoring system 1 in a shirt 3 integrated, which has a seam or longitudinal opening on its front 4 having. At the point of the seam 4 the shirt 3 can be opened to facilitate putting on. Buttons, zippers or Velcro fasteners or the like are particularly suitable as fastening means. Of course the shirt can 3 also have no seam, in which case it is over the torso 2 a patient is simply pulled over. A single sensor connector unit 5 is on the front of the shirt 3 integrated approximately at the waist. On the sensor connection unit 5 sensors (not shown) for monitoring a large number of parameters, in particular vital parameters, are connected.

The sensor connection unit 5 is designed so that a large number of commercially available sensors can be connected to it without further modification (see also 5 ). Furthermore, the sensor connection unit can also. a positioning sensor, such as a GPS or GALILEO receiver, can be connected to determine the location of the patient in the event of a critical or life-threatening situation or the data obtained in this way (e.g. height above sea level) when evaluating the medical data mitzuberücksichtigen. With regard to the types of position determination, the following options are particularly preferred in connection with the present invention.

• 1. Possibilities: Cell-ID, GPS, Assisted GPS, Differential GPS (D-GPS), E-OTD
• 2. Cell-ID: accuracy dependent of cell size, 500m up to 20 km (urban-rural)
• 3. E-OTD: with direction finding (requires> = 3 base stations within range), 100-500m I agree
• 4. GPS services:  Precise Pos. System PPS: only for US military personnel, up to 22m exactly  Standard Pos. System PLC: available for everyone, accurate to 100m  Assisted GPS: 5-50m accurate  Differential GPS (PLC mode): needs additional Software in the end device + Reference stations within range → accurate to 10m  Generally: HW receiver (+ antenna) necessary, but in combined radio modules available (e.g. TCG from Infineon)

Via a line 6 is the sensor connection unit 5 with a processing unit 7 connected. The processing unit 7 comes with a variety of snaps 8th detachable on the shirt 3 attached to the back. The processing unit 7 has a variety of functions, in particular the function of data acquisition, control and power supply. For further details regarding the processing unit 7 is to the following description, particularly in connection with the 3 and 4 directed. Via a line 9 is the processing unit 7 with one, an HF power splitter 10 and a variety of antennas 11 , which are preferably designed as slot antennas, having remote data transmission unit 12 connected. In the illustrated embodiment, the line runs 9 approximately along the patient's spine between the processing unit 7 and the HF power splitter 10 , The Powersplitter 10 stands over a multitude of lines 13 each with one of the multitude of antennas 11 in connection. In the illustrated embodiment there are four antennas 11 provided in the shoulder area of the patient, in each case two pairs opposite each other on the back or front shoulder area. The selected arrangement of the antennas 11 is particularly advantageous because it ensures optimal transmission and reception characteristics. The in the 1 and 2 components of the patient monitoring system according to the invention 1 are all except for the processing unit 7 firmly in the shirt 3 inte grated. The processing unit 7 is, in the embodiment by the push buttons 8th , in a simple way from the shirt 3 removable. In this way, a large number of patients can have their individual shirt 3 , in particular with regard to its (ready-made) size, are made permanently available, the expensive processing unit 7 is only made available in case of use. Furthermore, the processing unit can 7 easily removed, replaced, repaired or upgraded or modified in terms of software and hardware. The one in the shirt 3 integrated lines 6 are either conductive traces integrated into the clothing, for example plastic threads which are vapor-coated with silver / gold, which are woven directly into the garment or are woven onto carrier strips which are attached to the clothing, for example by sewing on. Furthermore, between the lines or the antennas 11 and shields may be provided to the patient's body. These shields can be made in particular from fabric sheets or patches and underlay the lines or antennas, the fabric sheets having metallic threads.

With reference to the 2 The structure of the processing unit is shown below 7 and the remote data transmission unit 12 explained in more detail. The block diagram of the 3 you can see that at the processing unit 7 connections 14 are provided to the sensor signals supplied by the sensor connection unit directly to a digital control unit 15 to lead. The digital control unit has, in particular (not shown) storage means for storing the data via the connections 14 save incoming signals at least temporarily. The digital control unit also has 15 Further functions, in particular, are stored in this software program, which enable an evaluation of the sensor signals. For example, alarm algorithms can be used for this. An example of such a method is disclosed in International Patent Publication No. WO99 / 67758, which is incorporated by reference in its entirety with the present disclosure. Furthermore, in the digital control unit 15 the data is also compressed and encrypted before being sent. The digital control unit 15 also serves to control the radio module. In practical terms, the digital control unit 15 realized by a low-power processor, which is capable of multitasking, for the simultaneous reception and processing of data from several simultaneously active sensors or other data. The digital control unit 15 is with a send / receive module 16 connected in which the essential functions of a cell phone or cell phone is integrated. The power supply of the digital control unit 15 and the send / receive module 16 takes place via batteries or accumulators 17 which has a power management processor 18 the control unit 15 and the send / receive module 16 supply with electricity. In the case of using accumulators there is a charge control device 19 in the processing unit 7 intended. A connection 20 is used to charge the batteries using a mains adapter. Alternative power sources can also be used 21 , for example solar cells or the like, for charging the batteries via a connection 22 be connected.

The one in the right part of the 3 shown remote data transmission unit 12 has an RF power splitter 10 on what about a connection 22 with the transmit / receive module 16 of the processing unit 7 communicates. The HF power splitter, which in a preferred exemplary embodiment of the present invention has an antenna diversity unit 24 which is connected via a connection 25 with the power management processor 18 the processing unit 7 is supplied with energy, controls four in the illustrated embodiment, as in the 1 and 2 arranged, planar antennas. Via the planar antennas 11 can send signals to the mobile patient monitoring system 1 sent and received by this. A transmission technology based on a radio telephone or mobile radio standard, for example GSM, GPRS or UMTS, is preferably used. About the antennas 11 all measured parameters and additional operating parameters of the system, e.g. battery level, software version, time, functionality of the connected sensors are ect. transferred to a service center (not shown) (DLZ). The antennas 11 are preferably flat and designed as slot antennas, the latter design having a particularly favorable radiation characteristic away from the patient.

On the digital control unit 15 the processing unit 7 is also a microphone 26 and a speaker 27 connected, for example in a headset system that can be worn by the patient or in a shirt 3 are integrated. In this way, the patient can use the processing unit 7 and the remote data transmission unit 12 especially exchange voice signals with the service center. For example, inquiries about the health status of a patient or behavioral measures can be transmitted by the service center. The patient can also transmit useful information to the service center using voice signals in addition to the sensor signals.

In 4 is the processing unit 7 shown in more detail in their design. In addition to the above description of the processing unit 7 based on 1 to 3 can he 4 are taken from that processing unit 7 via a connection 28 for connecting additional batteries, which are also attached to the shirt with press studs 3 are attachable. Furthermore, in 5 is the remote data transmission unit 12 shown in more detail, in particular in a preferred embodiment of the RF power splitter 10 is replaced by an HF power and diversity unit (see the description of the 3 ).

In 6 is another embodiment of a patient monitoring system 1 and further details of the data transmission to a service center (not shown). In the embodiment of the 6 are various sensors in the shirt that record vital signs 3 integrated. In detail, it is a pulse oximeter sensor 30 a non-invasive blood pressure sensor 31 , an ECG sensor 32 , a temperature sensor 33 and an actimeter or position sensor (accelerometer) 34 , The individual sensors 30 to 34 are via a star-shaped bus, which is described below with reference to the 7 and 9 is explained in further detail with the processing unit 7 connected, only the digital control unit in the drawing for simplification 15 is displayed. Also on the bus 35 is a microphone 26 and a speaker 27 , which together or individually can be referred to as a telecommunication device, in order to enable a communication connection, for example via voice, between the patient and the service center. Via the schematically displayed antenna 11 relevant information about the GSM, the GPRS or UMTS mobile radio standard or the like, possibly additionally encrypted, is sent to a PLMN provider (mobile radio network provider) 36 and then to a router, for example via a landline connection, in particular a dedicated line 37 transfer. From the router 37 the (encrypted) data transfer takes place to a server computer 38 , ie a central receiving station. The central receiving station is preferably located in a service center close to the clinic, in which the medical data are entered, stored and visualized. The incoming data is evaluated immediately, and intelligent alarm algorithms enable critical situations to be detected without delay. On the basis of the resulting data, retrospective analyzes of the stored data can also be carried out to generate standardized treatment guidelines (evidence-based medicine) and to conduct clinical studies. Via the schematically drawn radio connection 39 Both commands and other signals, in particular communication signals, can be transmitted from the service center to the patient and vice versa. The server computer 38 is connected to a database DB, in which the data of all patients involved are stored for further evaluation. Furthermore, the server computer 38 (, clinical CIS information _S ystem) to a clinic private network to the attending staff to provide the information optimally available. The server computer is optional 38 Connected to the Internet via a schematically illustrated firewall, preferably via an encrypted data connection, for example to enable the family doctor to provide protected access to the patient's data.

From a technical point of view it is the basis of transmission first to choose a suitable, already existing radio technology. There the complete Freedom of movement for the patient is a basic requirement of MMM on technologies for Short-range radio such as WLAN according to IEEE 802.11b, HomeRF or Bluetooth not resorted to become. Due to their short transmission range, they use one stationary Base station or an access point near the patient ahead.

It is therefore preferred to cover the entire area available and freely accessible Radio technology, namely the conventional Cellular radio or cell phone networks. such as. GSM / HSCSD or GPRS / UMTS. she is largely nationwide available and inexpensive realizable.

With regard to data transmission A distinction can be made between so-called CSD and PSD methods:

• - CSD (Circuit Switched Data): Before or after a data transfer a dedicated connection or disconnection is necessary and the Billing takes place based on time. GSM in the different variants (with 900/1800/1900 MHz) and HSCSD (High Speed Circuit Switched Data) are representatives of this transmission mode.
• - PSD (Packet Switched Data): After a one-time connection establishment the connection remains permanent (always-online), i.e. Data can can be sent if necessary without prior connection expansion and billing takes place after the transferred Data volume. GPRS (General Packet Radio Service) and the future UMTS (Universal Mobile Telecommunications System) are representatives of this newer transmission mode.

Another critical point is that Availability the radio connection, with the availability of the radio network in itself and availability a free radio channel is to be distinguished. While the influence on the first point when entering a radio hole e.g. in a tunnel only possible to a limited extent prioritize in the second point QoS mechanisms on the part of the network operator play an important role.

A big problem is the, compared with conventional wired network technologies such as LAN (Ethernet according to IEEE 802.3), low bandwidth of the radio networks listed above.

GSM has a gross data rate of only 9600 kbit / s. By bundling several GSM channels, HSCSD and GPRS achieve higher data rates, whereby the number of the maximum bundled channels is primarily limited by the hardware of the mobile station MS (cell phone, radio module). The number is different in the downlink or uplink (ie from the network provider to the MS or from the MS to the network provider) and is currently 3/1 or 2/2 for HSCSD and 4/2 channels for GPRS. The resulting larger downlink capacity is the result of the historical field of application, namely mobile internet surfing. With MMM, however, the capacity of the uplink is of crucial importance, since it is primarily about the transport of medical measurement data from the MS to the service center.

In addition, the gross data rate mitigated by necessary network and transport protocols such as TCP / IP. The one in reality achievable throughput depends Moreover of factors such as the network operator's network utilization, the antenna quality of the MS and their current environmental conditions (e.g. radio shading and user density in the current radio cell), so that the in Net data rates given in Table 1 are to be understood as mean values and are subject to strong fluctuations.

The currently realizable maximum Gross and net data rates of different cellular radio methods are listed in the following table.

Tabelle 1: Funktechnologien und Bandbreiten

Table 1: Radio technologies and bandwidths

Because of their wide distribution and easy integration into existing network structures TCP / IP is preferably selected as the network and transport protocol.

The requirements of what is based on it Application layer protocols essentially include:

• 1) the transfer both continuously and at intervals of vital data recorded of all kinds regarding Data format (byte, word etc.) and sampling rate.
• 2) the bidirectional transmission of operating parameters between MS and DLZ regarding a) Connection management: Phone number of the network provider, login password, IP address and certificates MedShirts and the receiving computer b) operating parameters of the MedShirts: battery level, time, etc. c) patient data d) Send mode: continuous send, push / poll mechanism e) medical sensors: device types the medical devices connected to the MedShirt and device-specific options such as e.g. Measuring intervals of an EKG device

When transferring e.g. continuous ECG raw data recorded can differentiate between the following approaches become:

• Continuous dispatch: none is found Data is stored in the MedShirt instead. This variant sets a permanently available Radio connection ahead and can be calculated with time-based tariffs (GSM, HSCSD) lead to high costs.
• - Data push at fixed intervals: the MedShirt stores the raw data and sends it at variable, but fixed time intervals; it can therefore be steplessly between a real-time transmission and an offline Mon monitoring (data transmission, for example, once a day) an appropriate operating mode can be set.
• - data pull through the receiving computer: as with the data push, only that the connection and the data transmission not through the Medshirt but through the DLZ is initiated.

Existing standards such as the in hospitals used HL7 that for the secure, confidential and asynchronous exchange of medical Data between doctors designed Healthcare Professionals Protocol or the transfer via XML are for other areas of application are designed and therefore only conditionally for this scenario suitable.

Because of the minor mentioned above Bandwidth of the radio link it is recommended the data in front of it Compress or reduce shipping. This leads to a reduction in transmission costs and the transmission time, what the response time in the case of a medically critical situation shorten can.

Tabelle 2: EKG-Datenraten und Datenaufkommen

Table 2: ECG data rates and data volume

Stand for lossless compression the well-known, widespread and freely available algorithms such as (adaptive) Huffman coding and Lempel-Ziv (LZ-77, LZ-88 / LZ-Welch) to disposal. To summarize tell yourself that the differences in compression methods in terms of the compression rate at relatively low Amounts of data far below 500 kByte per transmitted data packet, such as they occur at MMM, are hardly significant. Because of the often very limited Storage and computing capacities mobile devices are therefore simpler and therefore faster compression algorithms prefer.

Attention to data security aspects are particularly important in the medical environment. In particular in wireless transmission of data is the guarantee confidentiality due to an increased vulnerability of the radio link to eavesdropping attempts to consider.

In the GSM network and also on it establishing GPRS network is the data stream between the mobile station and the network components of the network operator by an A5 / 2 called Stream encryption method encrypted. While this already represents basic protection for some years now, doubts about the safety of this procedure. For example, by Adi Shamir already in the year 2000 a theoretical one Attacking a weaker Variant of AS / 2 called AS / 1 published. However, currently worked on the standardization of a new process called A5 / 3, which is based on the Kasumi algorithm, which will also be used in future UMTS networks are used and are considered to be very secure.

An extension is still an additional measure in the form of end-to-end encryption is desirable. This can e.g. based on existing solutions such as SSL (Secure Socket Layer) or IP-Sec VPNs (Virtual Private Networks) can be implemented, these protocols in turn being used for the transfer of medical Raw data available reduce the standing net bandwidth.

In 7 are two different implementations of the bus suitable for the present invention 35 shown schematically as a block diagram. The left part is the 7 a star configuration (point to point) is shown, in which a multiplicity of sensor connection units S are connected to corresponding connections of a measuring device M or the processing unit each directly via four (4) lines (two data lines and two power supply lines). In the right half of the 7 A so-called "party line" (multipoint) bus configuration is shown, in which all sensor connection units S or a single, structurally uniform sensor connection unit (not shown) are connected to the measurement device M via a common line (bus). The two bus configurations are in more detail in the 8th and 9 shown, the is in 8th star configuration shown in further detail is particularly preferred. In 8th and 9 the sensor is denoted by S. In 8th denotes a reference symbol 5 ' a sensor connection unit. In 9 are the sensor connection units with the reference symbol 5 ' referred to and can structurally also as a sensor connection unit 5 (see. 1 ) be formed together.

The invention has been described above of preferred embodiments closer to it explained. For one However, it is obvious to a person skilled in the art that different modifications and modifications can be made without departing from the invention deviate from underlying thoughts.

Claims (25)

Portable, mobile patient monitoring system, labeled by: - at least a sensor connection unit to which at least one sensor for monitoring of a parameter can be connected is; - one Processing unit through which the sensor connection unit supplied signals for transmission through the remote data transmission unit are processable, and - one Remote data transmission unit through which the transmission the signals supplied by the processing unit for evaluation same transferable is. Patient Monitoring System according to claim 1, characterized in that the at least one sensor one that describes or influences the condition of a patient Parameter senses. Patient Monitoring System according to one of the claims 1 or 2, characterized in that the sensor unit connectable Sensors record at least one of the following parameters: - ambient temperature - body temperature - EKG - EEG - CTG - EMG - EOG - blood oxygen saturation - blood pressure, especially non-invasive blood pressure - blood sugar - physical Activity. Patient Monitoring System according to one of the preceding claims, characterized in that a bus for connecting the sensors to the sensor connection unit is provided. Patient Monitoring System according to claim 4, characterized in that the bus is a star or has a party line configuration. Patient Monitoring System according to one of the preceding claims, characterized in that it into an outer garment is integrated. Patient Monitoring System according to claim 6, characterized in that the outer garment is a shirt or shirt or the like. Patient Monitoring System according to one of the preceding claims, characterized in that the remote data transmission unit has an RF power splitter and a variety of antennas. Patient Monitoring System according to claim 8, characterized in that at least one of the plurality of antennas is designed as slot antennas. Patient Monitoring System according to claim 8 or 9, characterized in that the antennas in Shoulder area of the outer garment are arranged. Patient Monitoring System according to one of the preceding claims, characterized in that the HF power splitter and the processing unit in the back area of the outer garment are. Patient Monitoring System according to one of the preceding claims, characterized in that the processing unit is detachable on the outer garment is appropriate. Patient Monitoring System according to one of the preceding claims, characterized in that the HF power splitter, the antennas, the sensor connection unit and the bus are integrated in the outer garment. Patient Monitoring System according to one of the preceding claims, characterized in that the processing unit that of the sensor connection unit data supplied for transmission via the Remote data transmission unit edited. Patient Monitoring System according to claim 14, characterized in that the preparation of the Data compression, encryption and caching having. Patient Monitoring System according to one of the preceding claims, characterized in that the mobile patient monitoring system further comprises a position determining device. Patient Monitoring System according to one of the preceding claims, characterized in that the mobile patient monitoring system furthermore has an authentication device. Patient Monitoring System according to one of the preceding claims, characterized in that the mobile patient monitoring system furthermore means for telecommunication of the patient with that for the evaluation competent Place, especially about Voice communication. Patient Monitoring System according to one of the preceding claims, characterized in that from the remote data transmission unit delivered signals operating parameters, e.g. Battery level, time, operability of the connected sensors, software version etc. Monitoring method of a patient, in particular with a patient monitoring system any of the preceding claims, being the transfer of data recorded by sensors from the patient to one Service center can be triggered manually, characterized in that that further in response to a transmitted to the patient monitoring system or from this command generated the transmission of by sensors recorded data from the patient to the service center triggered becomes. A method according to claim 20, characterized in that furthermore at predeterminable or adjustable times or time intervals a transfer of data recorded by sensors and / or of further operating parameters triggered by the patient to a service center. Method according to claim 20 or 21, characterized in that that the command is transmitted from the service center to the patient monitoring system becomes. Method according to one of claims 19 to 22, characterized in that that the command is provided by one in the patient monitoring system Processing unit in response to an evaluation of the sensor data is produced. Method according to one of claims 20 to 23, characterized in that that the sensor data is provided in a in the patient monitoring system Processing unit are temporarily stored, with a time delay and / or Times at which the transmission of the data to the Service center carried out becomes. A method according to claim 24, characterized in that the time delay and / or the times can be preset and also by a appropriate command from the processing unit or service center are adjustable.