1 / 30

Blood pressure

Blood pressure. Outline for today’s class. Question on Blood Pressure – review constants Cuff-with variety of methods to detect blood flow Errors in measurements- Bernoulli Tonography Solid state sensors Other pressure sensors 2 nd order model of catheter Statham / Millar transducers.

DoraAna
Download Presentation

Blood pressure

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Blood pressure

  2. Outline for today’s class • Question on Blood Pressure – review constants • Cuff-with variety of methods to detect blood flow • Errors in measurements- Bernoulli • Tonography • Solid state sensors • Other pressure sensors • 2nd order model of catheter • Statham / Millar transducers

  3. Blood Pressure Basics • Definition Pressure = Force/Area • At 0 deg C and standard gravity 981 cm/sec2 • Corrected for atmospheric changes • Units 1 torr =1 mm Hg =1328 dynes/cm2 =13.6 mm H20 =13.1 mm saline =12.9 mm blood

  4. Blood pressure questions • Where is the highest blood pressure in the body? • Where is the lowest blood pressure? • What is the minimum pressure needed to survive? • Why is your heart located in the chest? • How does a giraffe pump blood to it’s head? • What is your blood pressure in Denver compared to sea level? • Where are the pressure sensors in your body?

  5. Blood Pressure questions cont • How is blood pressure regulated? • What is the relationship between heart rate and body size? • What is the relationship between heart rate and respiration? • How do you measure blood pressure in the capillaries? • What is your blood pressure in Denver compared to sea level? • Does blood pressure have to be pulsitile? • Does the pulse reach all the body at once? • What is origin of Korotkoff sounds?

  6. Sources of Error-velocity effect Total Energy= Pressure energy + velocity energy + height energy E = Ps + Mgh +(1/2)mv2 Where: Ps = Static Pressure M= mass g=gravitational accelleration V=velocity

  7. Bernoulli effect In this example of a fluid flowing initially in a large cylinder and then flowing in a small cylinder before returning to the large cylinder, note that the velocity in the middle must increase. Since the Total Energy must be the same, the increased velocity means more kinetic energy, the resulting static pressure must be less

  8. Velocity/pressure errors in body

  9. Average Blood Pressure

  10. Drug store meter

  11. Ultrasound methods

  12. Tonometry

  13. Tonometer system blocks

  14. Catheter properties

  15. Model of catheter segment

  16. Frequency –Bode plot

  17. Differential equation

  18. Frequency response

  19. Other 2nd order systems Mechanical systems Body motion Fluid systems Transducer sensors Oxygen diffusion models Feedback model elements

  20. Simple pressure transducers - Bourdon tube- Bellows

  21. Millar pressure sensor

  22. Indirect capillary pressure measurements

  23. Optical pressure catheter sensor

  24. Statham Transducer Dangers of Air Bubble -loss of frequency fidelity -air bubble entering blood -Possible stokes or ministrokes

  25. Pressure sensor for Eye Pressures

  26. Project Suggestions • OR Open heart equipment – pumps • Anesthesia console • Pacemakers • Cardiac defribulators • Ventilator – artificial respirators • New born cribs • Smart beds • Sound level monitors • Audiology testing machines • Kidney dialysis equipment

  27. Project suggestions • Blood testing devices • Blood gas measurement devices • Robots used in surgery • Telemedicine • Devices in Emergency Vehicles • Devices in helicopters • Drug administration devices • Hospital computer systems • OR monitors • Blood pressure measurement instruments

  28. Project suggestions • Liver dialysis devices • Emergency Room devices • Stethoscopes – electronic and plain • Imaging devices – MRI, SPECT, CT, PET • Ultrasound devices • Implantable joints, bones, teeth • Artificial hearts, muscles • Devices for the blind, deaf, dumb, no smell, etc • Scooters, wheelchairs • Medical equipment on the space shuttle

  29. Project suggestions • Biomedical devices for animals • Biomedical transmitters • Eye diagnostics devices • Neuro-implants – EEG analysis • Devices used or needed in poor countries • Ancient biomedical devices • Acupuncture, electrical stimulators • Artificial skin, blood, tendons • Diabetes devices – meters, auto infusion • Lie detectors • Software to assist diagnosis and treatment

  30. Project suggestions • Exercise machine and their efficacy • Glues used in the body and teeth • Electronic nose • Devices used in delivery rooms • New baby respiration monitors • Artificial implantable lenses for the eye • Retinal and brain implants for artificial vision • Heart valves, artificial arteries, stents • Medical records – voice input • DNA testing, decoding devices

More Related