TeleHealth Module

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Revision as of 02:25, 16 November 2007 by Steveb07 (talk | contribs) (→‎ADC/DAC)
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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

  • 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

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.

THMDB

http://wiki.laptop.org/go/Telehealth_module_database

Contributors

  • Ian Daniher
  • Zdenek Broz
  • Ram Dhurjaty (Simple concept suggested elsewhere)
  • Rafael Ortiz

Resources