Remote Patient Monitoring
It is essential that data collection points be located as close to the patient as possible. It is widely anticipated that future health information systems (HIS) will need to move from “institution-based” models to those that rely on ‘near real time’ data integration close to the patient. This paradigm shift will need to allow a patient to lead a normal (mobile) lifestyle whilst at the same time collecting the data that permits pro-active monitoring of their condition. Constant monitoring of a medical situation allows complications to be detected sooner, thus providing opportunities for earlier intervention to manage the condition. Rigorous, system-based management of chronic conditions is essential to improve healthcare outcomes. Conventional models of healthcare provision lack the capacity to continuously monitor physiological data combined with life event ‘timelining’. In such an information system, healthcare can be provided in a ‘patient-centric’ model that optimises the use of healthcare resources.
To achieve ‘near real time’ data collection and integration close to the patient, the approach to remote patient monitoring described below has been used in Healthcare@Home.
A patient, for example, takes a blood pressure (BP) reading using a BP monitoring device. The reading is transmitted to a data ‘hub’ (a mobile phone in this example) via Bluetooth® wireless technology. A fingerprint device is used to authenticate the patient's identity for the reading. The Hub then transmits the reading to the Healthcare@Home servers for validation, storage and inspection / analysis. The hub can also assist collection of ad-hoc ‘diary entries’ pertaining to, for example, food consumed and exercise undertaken.
To make the above example possible, Healthcare@Home partners have developed and integrated several elements of technology that either did not exist before or that have not previously been made to work together. These are:
- A novel biomedical sensor device for non-invasive monitoring of blood glucose levels, developed by Smart Holograms;
- A biometric device for authenticating the identity of the patient for whom data readings are being collected, developed by Zarlink Semiconductor;
- A data hub for the collection and combining of data readings and authenticated identity information for onward transmission to Healthcare@Home servers, developed by IBM.
Biomedical sensor device
Sensor holograms, developed by partner Smart Holograms, are stimuli-responsive hydrogels with laser imprinted images. They can change image, wavelength, position or brightness in response to a programmed physical, chemical or biological stimulus. The degree of swelling or contraction of the hydrogel affects the optical properties of the embedded hologram and this can be correlated with the concentration of the body fluid analyte of interest (glucose in the case of diabetes).
The prototype hand-held device (photo) has a touch-screen user interface. The reader employs a bespoke spectrometer optical sub-assembly, combined with analogue to digital converters (ADCs). These ADCs are read by a microprocessor which provides a calibrated output of wavelength and the corresponding concentration of the analyte being measured. This is achieved by use of look up tables or calibrated polynomial curve fit data. Temporal data trends can be calculated on-device or data can be sent via Bluetooth® to the Healthcare@Home servers to enable downstream decision support.
Biometric authentication device
system requires technology options that are cost-effective, fast and accurate. Based on these criteria, we chose to use robust fingerprint recognition technology to meet our biometric authentication requirements. The Biometrics module developed by Zarlink Semiconductor
uses fingerprint recognition algorithms for detection and storage of up to 3000 fingerprints. Individual fingerprints are associated with a user identity code that can be transmitted via Bluetooth®
to another device, such as the home hub. For flexibility, the biometric device has been designed to be “loosely-coupled” with the biomedical sensor and the home hub modules. This permits different packaging options to be adopted and integration with new sensor types without incurring substantial additional engineering costs. The hub (see below) associates the identity sent from biometric authentication device with received sensor data in order to form an association between a patient identity and a data reading.
The function of the ‘home hub’, designed by IBM, is to collect and collate the data from sensor(s) and identity authentication device(s) and to co-transmit these via an appropriate communication channel to the remotely-located Healthcare@Home server. The home hub sits at the centre of the data collection and transmission capability of the system, where all devices - sensors, authentication module and server connect through common interfaces. Various physical realizations of the hub are possible. It can, for example, be a mobile device such as a standard mobile phone (we have demonstrated functionality on a Sony Ericsson P910 phone) that can provide near real-time data connectivity. The hub can also be deployed as a fixed ‘wired’ hub using, for example, Ethernet connectivity. In a clinical environment this also provides near real-time data connectivity. For home use, hubs can be configured to upload data periodically (e.g., once or twice a day) via home broadband connections. The hub has made use of IBM's Personal Care Connect toolkit for developing mobile health monitoring applications.