SIDS Detection Via Oximetry and Pulse

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SIDS DetectionVia Oximetry and Pulse

• Benjamin Cichy, Jonathan Wang
• bcichy_at_ucsd.edu,jwang_at_ucsd.edu

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Problem Statement

• Sudden Infant Death Syndrome
• Ubiquitous umbrella term
• Prevention and detection
• Physiologial benefits
• Mental trauma
• Problem definition not absolute
• Asphyxia
• Congenital causes
• Facts
• Highest number is at 2 to 4 months 91 occur
  between 1 to 6 months of age.
• Sleep Apnea related to sleeping position

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SIDS Rate and Sleep Position
Source National Institute of Child Health and
Human Development Household Survey Final Data
1999, National Center for Health Statistics,
Centers for Disease Control and Prevention
SIDS rates have decreased and percent of
back/side sleeping has increased since the
campaign began.
Yellow (19851991) Pre-AAP recommendation Blue
(19921994) Post-AAP recommendation Red
(19951999) Back to Sleep campaign
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Project description

• Project
• Definition by asphyxia
• Physical changes
• Model hypoxic subject
• Track changes rapidly
• Immediate(RT) computation
• Alert guardian/parent/staff
• Market
• Parents
• Child care providers
• Hospitals

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Technical Description
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Hardware Description -Board

• Board
• Accelent LRH board with StrongARM processor
• StrongARM processing

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Hardware Description -Oximeter

• Sensoring
• Oximeter flow sensor
• Measures oxygenation of blood
• Pulse
• Measures pulse rate in bps
• Serial output 9600, n, 8, 1
• Data rate 3Bps
• Specifications

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Glossary/Terminology

• Apnea
• Cessation of breathing
• Hypoxia
• Reduction of oxygen supply
• Hyperoxia
• Excess oxygenation
• Hypopnea
• Shallow breathing
• Hypoxemia
• Low oxygen content
• Hypercarbia
• Excess carbon dioxide

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Software Algorithm

• Thresholds
• Sp02
• Normal Range 95-99
• 80-94
• lt 94
• lt 80
• 88 gt 10 sec
• 88 gt 160bps
• Code example

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Normal Pulse Readings
Notereadings in bpm, beats per minute
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State Chart
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Sp02 Readings
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Analysis/Discussion
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Results/Conclusions

• None so far
• Only literature study so far
• Need proper asphyxia model using oximeter
• Need temperature data and curve fit to differing
  subjects
• Learning mode, same for oximeter
• Model dO2/dt, not

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Noted Events

• Artifacts
• Errors
• Timing errors with Oximeter
• Out of range
• Errors generate immediate alert
• Smoothing errors
• Pulse smoothing
• Need to control function
• Constraint real time analysis

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Future Work

• Temperature Sensor
• Infant temp variation
• CO2 Sensor
• Complement to Sp02 concentration
• Larger memory
• Trend tracking
• Personalized sensing
• Power Management
• FPGA or ASIC integration
• IEEE802.11
• Wireless monitoring

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References

• 1 Kim, J.M. Kim, S.H. Lee, D.J. Lim, H.S.
  Signal Processing Using Fourier Wavelet
  Transform for Pulse Oximetry, The 4th Pacific Rim
  Conference on Lasers and Electro-Optics, 2001
  (CLEO/Pacific Rim 2001), pp. II-310 II-311.
• 2 Rusch, T. Scharf, J. Sankar, R. Alternate
  Pulse Oximetry Algorithms for SpO2 Computation,
  Proc. 16th Annual International Conf. of the IEEE
  Engineering in Medicine and Biology Society,
  Baltimore, MD, November 1994, pp. 848-849.
• 3 Rusch, T. Scharf, J. Sankar, R. Signal
  Processing Methods for Pulse Oximetry, Computers
  in Biology Medicine, vol.26, no.2, Elsevier,
  UK, March 1996, pp.143-59.
• Sids
• 4 Filiano, J.J. and Kinney, H.C. "A Perspective
  on Neuropathologic Findings in Infants of the
  Sudden Infant Death Syndrome The Triple Risk
  Model." Biology of the Neonate 1994
  65(34)1947.
• 5 Corr, C.A., Fuller, H., Barnickol, C.A., and
  Corr, D.M. (Eds.). Sudden Infant Death Syndrome
  Who Can Help and How. New York Springer
  Publishing Co., 1991.
• 6 Bergmen, Abraham. B Beckwith, Bruce J.
  (Eds.) (1970). Sudden Infant Death Syndrome.
  Seattle University of Washington Press.
• 7 Hwang, Mi Young. (1998). Rock-a-bye Baby ...
  on Their Backs Dangers of Infants Sleeping on
  Their Stomachs and Sudden Infant Death Syndrome.
  The Journal of American Medicine. 280 ,396.
• 8 Kinney, Hannah. (2000). NICHD-Funded
  Researchers Uncover Abnormal Brain Pathways In
  SIDS
• 9Victims Journal of Neuropathology and
  Experimental Neurology 59, 5, 377-384.
• Parment, Sharon (2002). Sudden Infant Death
  Research The Journal of American Medicine, 288,
  21.
• 10 National SIDS/Infant Death Resource Center.
  http//www.sidscenter.org/ (April 2004).
• 11 SIS Alliance, http//www.sidsalliance.org/ind
  ex/default.asp (April 2004)
• 12 Sleep Review Magzine http//www.sleepreviewm
  ag.com/Articles.ASP?articleidS0311F02, 2002.
• 13 Respiratory Reviews http//www.respiratoryrev
  iews.com/jun01/rr_jun01_litmonsters.html
• 14 Kids Growth http//www.kidsgrowth.com/resourc
  es/articledetail.cfm?id882
• Hardware
• 15 Nonin Manual. Nonin Medical
  http//www.nonin.com/