Medical WSNs

Challenges

• reliability
• privacy and security
• power management - not all devices are battery powered
• diversity - both a challenge and an opportunity
• fast deployment - disaster recovery scenarios

Medical devices

• ECG
• SpO2
• Blood pressure (CardGuard)
• Motion analysis board
  • for Parkinson's, to identify uncontrolled shaking and fine-tune dosage -- Code blue
  • for detecting falls -- UVA

Groups

• University of Virginia: Alarm-NET
• Intel Research Seattle
• University of Washington
• University of Rochester
• Harvard University
• John Hopkins: AID-N

Projects

Overview

Project	Domain	Network Architecture	Devices	Sensors	Provides
Code Blue	Patient Monitoring	Motes	Motes	SpO2, EKG, motion	Patient monitoring, Reliable Routing, Localization
csdcsd	cdscsd

CodeBlue

• AMDR Routing:
  • support for pub/sub
  • routing state proportional to the # of publishers (an entry in the table for each publisher)
  • route discovery initiated when a device requests to publish data, requires flooding
  • a subscriber that wants to receive data from a channel sends a route reply on the reverse path (handles asymmetric links)
  • routes are updated through periodic floods (every 15s)
  • negative results on mobility
  • path metric (PDR)
    • for each link, estimate LDR by mapping the measured LQI to a link delivery estimator. This model is determined empirically.
    • PDR is the product of all LDRs of the links along the path
  • see CodeBlue Technical Report

SMART (Scalable Medeical Alert Response Technology)

• Domain: disaster recovery, triage
• Network architecture: 802.11b
  • Two types of devices: patient monitoring and caregiver
• Devices: PDAs
• Sensors:
  • medical: SpO2, ECG from MIT
• Functions:
  • vital sign monitoring
  • vital sign analysis & alarms
  • localization

Notes:

Good background section.

References:

1. Curtis DW, Pino EJ, Bailey JM, Shih EI, Waterman J, Vinterbo SA, Stair TO, Guttag JV, Greenes RA, Ohno-Machado L, SMART An Integrated Wireless System for Monitoring Unattended Patients. J Am Med Inform Assoc 2008 January-February; 15(1):44-53.

AID-N (Advanced Health and Disaster Network)

• Domain: disaster recovery, triage
• Network architecture:
  • 802.11 -- one hop
  • 802.15.4 -- seems one hop
• Devices: motes, PDAs, PCs
• Sensors:
  • medical
  • non-medical: GPS
• Functions:
  • monitoring and alarm
  • vital sign analysis & alarms

References:

1. Tia Gao; D. Greenspan; M. Welsh; R.R. Juang; A. Alm, "Vital Signs Monitoring and Patient Tracking Over a Wireless Network," Engineering in Medicine and Biology Society, 2005. IEEE-EMBS 2005. 27th Annual International Conference of the , vol., no., pp.102-105, 2005

Alarm-NET

• Domain: assisted living, circadian activity rhythms (CAR)
• Network architecture:
  • Spans body networks, sensor networks and IP networks
  • Query service to collect data
  • Emphasis on dynamic security
  • Use CAR information for security and power management
• Devices: heterogeneous - motes, PDAs and PCs
• Sensors:
  • medical: pulse, blood oxygenaton
  • non-medical: temperature, light, infrared motion

References:

1. A. Wood, G. Virone, T. Doan, Q. Cao, L. Selavo, Y. Wu, L. Fang, Z. He, S. Lin, J. Stankovic, “ALARM-NET: Wireless Sensor Networks for Assisted-Living and Residential Monitoring,” Technical Report

News

Band-aids