Steady advances in wireless networking, medical sensors, and interoperability software create exciting possibilities for improving the way we provide emergency care. The Advanced Health and Disaster Aid Network (AID-N), being developed at The Johns Hopkins University Applied Physics Laboratory, explores and showcases how these advances in technology can be employed to assist victims and responders in times of emergency. The scope of this paper covers a subset of the technologies in AID-N.
We have developed a system that facilitates collaborative and time-critical patient care in the emergency response community. During a mass casualty disaster, one of the most urgent problems at the scene is the overwhelming number of patients that must be monitored and tracked by each first responder. The ability to automate these tasks could greatly relieve the workload for each responder, increase the quality and quantity of patient care, and more efficiently deliver patients to the hospital. Our system accomplishes this through the following technologies: • Wearable sensors to sense and record vital signs into an electronic patient record database. This dramatically improves the current time-consuming process of manually recording vital signs onto hardcopy pre-
Manuscript received July 22, 2005. This work was supported in part by the U.S. National Library of Medicine under Grant N01-LM-3-3516.
T. Gao is with the Johns Hopkins University Applied Physics Lab, Laurel, MD 20723 USA (phone: 240-228-3475; fax: 301-762-8230; e-mail: tia.gao@jhuapl.edu).
D. Greenspan is with the Johns Hopkins University Applied Physics Lab, Laurel, MD 20723 USA (e-mail: daniel.greenspan@jhuapl.edu).
M. Welsh is with the Division of Eng. and Applied Sciences, Harvard University, Cambridge, MA 02138 USA (e-mail: mdw@eecs.harvard.edu).
R. R. Juang is with the Johns Hopkins University Applied Physics Lab, Laurel, MD 20723 USA (e-mail: rayver@hkn.berkeley.edu).
A. Alm is with the Johns Hopkins University Applied Physics Lab, Laurel, MD 20723 USA (e-mail: alexander.alm@jhuapl.edu). hospital care reports and then converting the reports into electronic format. • Pre-hospital patient care software with algorithms to continuously monitor patients’ vital signs and alert the first responders of critical changes. • A secure web portal that allows authenticated users to collaborate and share real-time patient information.
II. METHODOLOGY
During health emergencies, when time is of the essence, there is little tolerance for system errors and poor usability designs. Through the use of standards-based software and best-of-breed hardware, our goal is to deliver a system which is scalable, reliable, and user-friendly.
Our patient monitoring and tracking system extends upon the CodeBlue project from Harvard University [1]. CodeBlue is a distributed wireless sensor network for sensing and transmitting vital signs and geolocation data. Figure 1 illustrates our current prototypes. A wearable computer attached to the patient’s wrist, commonly known as smart dust or a mote, forms an ad hoc wireless network with a portable tablet PC. We’ve integrated several peripheral devices with the mote, including location sensors for both indoor and outdoor use, a pulse oximeter, a blood pressure sensor, and an electronic triage tag. The electronic triage tag allows the medic to set the triage color (red/yellow/green) of the patient at the push of a button. It replaces the paper triage tags that are commonly used by medics today. The mote also has onboard memory for storing the patient medical record.
As in Fig. 1, the mote continuously transmits patient information to the first responder’s tablet device. The transmission uses the TinyOS Active Messages protocol, which is based on the IEEE 802.15.4 standard [2]. The mote was originally developed at the University of California Berkeley in the late 1990’s. Since then, it has gained significant interest from academia and industry for