Jianchu Yao

A wearable point-of-care system for home use that incorporates plug-and-play and wireless standards

A point-of-care system for continuous health monitoring should be wearable, easy to use, and affordable to promote patient independence and facilitate acceptance of new home healthcare technology. Reconfigurability, interoperability, and scalability are important. Standardization supports these requirements, and encourages an open market where lower product prices result from vendor competition. This paper first discusses candidate standards for wireless communication, plug-and-play device interoperability, and medical information exchange in point-of-care systems. It then addresses the design and implementation of a wearable, plug-and-play system for home care which adopts the IEEE 1073 Medical Information Bus (MIB) standards, and uses Bluetooth as the wireless communication protocol. This standards-based system maximizes user mobility by incorporating a three-level architecture populated by base stations, wearable data loggers, and wearable sensors. Design issues include the implementation of the MIB standards on microcontroller-driven embedded devices, low power consumption, wireless data exchange, and data storage and transmission in a reconfigurable body-area network.

Applying the ISO/IEEE 11073 Standards to Wearable Home Health Monitoring Systems

Objective. The goal of this effort was to investigate the feasibility of applying the ISO/IEEE 11073 (a.k.a. X73) standards, originally intended for bedside monitoring in hospital environments, to wearable, multi-sensor monitoring systems designed for home healthcare. Methods. The X73 upper-layer sub-standards (i.e., nomenclature specification, domain information model, application profiles, and vital sign device descriptions) were adopted and implemented on microcontroller-based sensor hardware to provide plug-and-play medical components. Three types of system elements (base stations, data loggers, and sensor units) perform the functionality required in this standards-based home health monitoring system and communicate using Bluetooth wireless modules. The base station incorporates a LabVIEW interface running on a personal computer. Each data logger and sensor unit is implemented on a microcontroller-driven embedded platform. Sensor units include wearable sensors (e.g., electrocardiograph, pulse oximeter) and nearby sensors (e.g., weight scale, ambient environment sensors). Results. The standards-based prototype system with an open architecture achieves plug-and-play performance suitable for a home environment. Each wireless element in the body/home area network can automatically detect other nearby devices, associate with them, and exchange data with them as appropriate. Conclusions. With minor modifications, the X73 standards can be successfully applied to wearable, wireless, point-of-care systems in the home.

Wearable sensors and component-based design for home health care

Recent technology trends indicate that truly cost-effective home health care systems of the future will be constructed from distributed, plug-and-play, commodity components assembled on-the-fly to match the needs of a given patient. This paper describes early efforts in the Medical Component Design Laboratory: a research and teaching laboratory where component technologies developed for research will support student projects in closely related engineering courses. Two component-based prototypes are presented in this paper: a Bluetooth-enabled personal monitoring system and a plug-and-play pulse oximeter.

Design of a plug-and-play pulse oximeter

Presents the design of a plug-and-play pulse oximeter that communicates with a LabVIEW virtual instrument. The sensor module samples plethysmographic data and sends them to a personal computer via an RS-232 serial link. The system configuration is described, and the response of the system is discussed when either the computer, sensor, or RS-232 connection breaks down. The oximeter is suitable for home use and can reliably collect pulsatile data from multiple body locations (e.g. finger, forehead, palm, etc.).

A novel algorithm to separate motion artifacts from photoplethysmographic signals obtained with a reflectance pulse oximeter

Pulse oximeters are mainstays for acquiring blood oxygen saturation in static environments such as hospital rooms. However, motion artifacts prevent their broad in wearable, ambulatory environments. To this end, we present a novel algorithm to separate the motion artifacts from plethysmographic data gathered by pulse oximeters. This algorithm, based on the Beer-Lambert law, requires photoplethysmographic data acquired at three excitation wavelengths. The algorithm can calculate venous blood oxygen saturation (S/sub v/O/sub 2/) as well as arterial blood oxygen saturation (SaO/sub 2/). Preliminary results indicate that the extraction of the venous signal, which is assumed to be most affected by motions, is successful with data acquired from a reflectance-mode sensor.

Implementation of a standards-based pulse oximeter on a wearable, embedded platform

This paper addresses software design considerations in implementing the medical information bus (MIB) standard on a wearable pulse oximeter. Underlying hardware constraints greatly influence software operation and performance. This design uses a PIC18 microcontroller with software written in C. A modified version of an MIB software implementation by Alaris medical systems will run on this hardware/software configuration. A hardware prototype has been created, and the underlying software is currently in development.

A distributed infrastructure for veterinary telemedicine

The livestock industry can benefit tremendously from systems that continuously monitor cattle state-of-health, allowing the industry to maintain high meat quality, react to the presence of disease, and predict its spread. Requirements for these monitoring systems are similar to requirements that drive human ambulatory monitoring systems based on wearable sensors and wireless data communication. This paper presents early results from an effort to develop a veterinary telemedicine infrastructure based upon wearable monitoring technology originally developed for home health care. The functional layout of the infrastructure is described, and initial hardware and physiological measurements are presented.

Reconfigurable Point-of-Care Systems Designed with Interoperability Standards

Interoperability standards, if properly applied to medical system design, have the potential to decrease the cost of point-of-care monitoring systems while better matching systems to patient needs. This paper presents a brief editorial overview of future monitoring environments, followed by a short listing of smart-home and wearable-device efforts. This is followed by a summary of recent efforts in the Medical Component Design Laboratory at Kansas State University to address interoperability issues in point-of-care systems by incorporating the Bluetooth Host Controller Interface, the IEEE 1073 Medical Information Bus, and Health Level 7 (HL7) into a monitoring system that hosts wearable or nearby wireless devices. This wireless demonstration system includes a wearable electrocardiogram, wearable pulse oximeter, wearable data logger, weight scale, and LabVIEW base station. Data are exchanged between local and remote MySQL databases using the HL7 standard for medical information exchange.

Lessons Learned from Applying Interoperability and Information Exchange Standards to a Wearable Point-Of-Care System

Interoperability at the device and system levels has the potential to improve ease of use for point-of-care systems while lowering the cost of these systems. To this end, we developed a prototype wearable monitoring system based on interoperability standards that demonstrates plug-and-play wireless connectivity between the system components. The system utilizes both device-level (IEEE 11073, Bluetooth) and system-level (Health Level (HL7), CORBA) standards. The wearable monitoring system stores data in a local database, and these data are then sent to a remote database via HL7 messages. The remote data can be viewed and processed with a graphical user interface created in Java that employs the CORBAmed PIDS and COAS services as implemented by OpenEMed. The lessons learned from this endeavor are summarized in this paper

A wearable standards-based point-of-care system for home use

From a users point of view, a point-of-care system for home use should be wearable and easy to use in addition to satisfying requirements for medical devices. In this paper, we address mobility, power consumption, data storage, data transmission, and device synchronization for wearable home care devices that comply with the IEEE 1073 (medical information bus) standard. A wearable, standards-based, plug-and-play system for home care that utilizes IEEE 1073 and off-the-shelf components is presented. This work will result in proposed enhancements to IEEE 1073.