TeleHealth Module

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The 10usd TeleHealth Module

  • This low cost, multifunction peripheral will provide a means through which the XO can relay valuable medical diagnostic data from the field to doctors many kilometers away.
  • It will compose of a three lead EKG providing valuable information about the heart's electrical status, enabling diagnosis of congenital defects and various arrhythmias.
  • It will also contain a multipurpose NIR diagnosis tool whose primary function is that of a pulse oximeter, providing information about the oxygen saturation of the blood.
    • See nirdiagnositics.com for other NIR functions

3 Electrode EKG

  • Uses
    • This is an excellent way to help children learn about the behavior of the heart.
    • Can be a way of prevent and diagnose diseases.
    • Can be a way to recognize congenital defects of the heart.
  • Key features
    • Safety
    • Low Cost
    • Simplicity of interface
    • Good documentation, possibly via svg/javascript animations.
  • How to do it
    • The first part is the actual hardware part. A circuit, possibly USB powered, using op-amps, would amplify the signal received by the sensor array(of three to twelve electrodes in contact with the skin, in proximity to the heart), to a level readable by the sound-card.
    • The second part is the safety part, when we are dealing with the heart there is a very real risk of causing serious problems via current leakage.
    • The third part is adapt Measure to increase functionality as a Telemedicine platform.
      • To increase interface functionality
      • To add software selections for pulse oximeter, EKG, to accommodate the difference in waveform type
      • To add diagnosis functionality
      • To add graphical depictions of biosign activity(heart-beat?)
  • Implementation
    • Multiple Op-Amps pick up, amplify, and filter electrical impulses picked up by near-heart electrodes.
      • Older EKGs used suction based reusable electrodes, an adaption of these may be best suited for the third world where replacements are scarce.
    • DyD/DyDisMe has schematics for an EKG using AD620A style op-amps.
      • 4.1044-7.3 usd
    • Ram Dhurjaty, a medical device professional who has had substantial experience with EKG amplifiers, has pointed suggested that there are better amplifiers than the AD620.
    • Dirakx(Rafael Ortiz) is currently in the prototyping phase of an EKG, to incorporate into the THM, as of Nov. 14th of 2007
    • Now we have an excellent way to do an ECG measurement, through Measure.
  • Extensions
    • EEG - Electroencephalography
    • EMG - Electromyography
    • EOG - Electro-oculography
    • SpO2 - Pulse-oximetry.

The long time consuming part

  • Get approval from the health organizations.


NIR Diagnosis Aid

  • Based on the principles of the differences in absorption of oxygenated and non oxygenated hemoglobin
  • 800-1000nm light from LEDs are often used in NIR tools
    • The most cited frequencies for IR Pulse Oximetery include 805nm, 910nm, and 940nm.
    • 940nm IR LED; 12.2c per unit
  • Red light is generated from similar LEDs.
    • 10-20c per unit
  • Light is picked up by photodiodes, converted to current.
  • This current is amplified and converted to voltage by a MAX4006 or equivalent chip
    • 1.275 usd

ADC/DAC

  • C8051F321 or equivalent chip
    • A/D 5x10b minimum
    • This specific chip provides A/D 13x10b
  • alternatively a USB micro-controller may communicate with dedicated ADC/DAC chips via PWM, to lower cost.
  • Honza Kovar(Jan), from the Czech republic, has acquired development board for the C8051F321 MCU, and will assist with programing and development.

THMDB

TeleHealth Database

Contributors

  • Ian Daniher
  • Honza Kovar
  • Ram Dhurjaty (Simple concept suggested elsewhere)
  • Rafael Ortiz
  • Steve Burns

Resources