Case Studies, Insights

10 Things You Should Know About Oximetry

Since its original broadcast in November 2017, 10 Things You Should Know About Oximetry has been one of our most popular webinars. This casual yet fast-paced presentation features important points on pulse oximetry from Keith Wesley, MD, FACEP, FAEMS. Wesley is a recognized expert in emergency medicine, with volumes of valuable knowledge to share.


  1. The Basics of Pulse Oximetry: A procedure that noninvasively measures the amount of oxygen in the blood, frequently performed in an EMS setting.
  2. Pulse Oximetry Gives Clues to Perfusion and Oxygenation: Indicating how sick the patient is.
  3. Oximetry Can Guide Care: Too much, or too little oxygen can be harmful depending on the patient’s state. A reliable oximeter will show you the O2 level so you can administer oxygen accordingly.
  4. Use the Right Size Sensor for You Patient: Pediatric vs. adult patients need appropriately sized sensors to obtain accurate diagnostics.
  5. Indication for Use Are Vital to Your Success with an Oximeter: If it doesn’t say “indicated for poor perfused patients” or “intended for use in EMS environments,” it will likely fail to perform in those situations. Nonin’s Onyx Vantage 9590 is specifically indicated for use in EMS environments, and for patients with low perfusion.
  6. Testing an Oximeter on Yourself or on a Few Patients is Not Representative of Large Scale EMS Usage: Additionally, comparing a lower cost device against your clinically proven, more expensive device can be a mistake when assessing oximeters.
  7. Response Delay Times Vary Depending on Where You Place the Sensor: 
    1. Heart to Finger – 30 seconds
    2. Heart to Forehead – 10 seconds
    3. Heart to Toes – 90 seconds
  8. Cold Hands? Fresh Manicure? These are Some Possible Causes for Erroneous Readings: Cold extremities cause low regional perfusion which could result in a false reading if you do not have the right oximeter.
  9. Amazon: They sell everything, including pulse oximeters. But the indications for use specifically mention that they are not suited for medical use. Don’t make that mistake! Oximeters sold at drug stores and on Amazon simply do not compare to a clinically proven and tested medical device.
  10. Not All FDA Cleared Oximeters Perform Alike: Check out this study from Clinimark Laboratories showing the difference in FDA cleared oximeters. Nonin’s device performed above the rest, and is clearly the most reliable of the oximeters tested. To learn more, click here.