How to Use an Ear Oximeter Probe

Using the ear clip pulse oximeter probe is not difficult, but tricky for some patients. A pulse oximeter works by shining two lights at different frequencies through the body tissue and then based on the amount of light absorbed by the body tissue. Light can be absorbed by the bone, nail or flesh and the absorption is constant. The other component is light absorbed by blood which varies as the heart pumps blood throughout the body. The calculation of SpO2 is based on the varying component of the signal. If any of these two components is too high or too low, the oximeter will not be able to give a proper reading.

Here are some of the conditions when an ear probe may not work.

  • Scar, cartilage, or other unusual skin condition may prevent light from going through.
  • The tissue at the spot is too "thin" and light just goes through with little absorption. This would result in finger out condition.
  • If the LED lights and detectors are not fully covered by the ear tissue, outside light would interfere with the detection.
  • If there is insufficient blood flow, the varying signal component would be too weak for proper detection.

If you encounter problem using the ear clip oximeter probe, try the following.

  • Try the clip on the finger to make sure that the clip produces a correct SpO2 reading.
  • Clean the LED lights and detectors according to manufacturer's instruction.
  • Position the clip at different parts of the ear, making sure that both the LED lights and detectors are fully covered by ear tissues. Avoid spots with unusual skin conditions.
  • Use an alcohol pad to massage the patient's ear gently for 15 to 20 seconds before taking a reading. This is to increase blood circulation.
  • Try different parts of the body. For example, position the probe on the cheek from outside to inside of the month. Make sure the probe is clean before trying.