Signal Noise; Figure 2-3. Low Perfusion Waveform; Figure 2-4. Noisy Plethysmographic Waveform - GE TruTrak+ 3900 User Manual

CHECK SENSOR SITE

Figure 2-3. Low perfusion waveform

Signal noise

The following conditions can cause noisy waveforms:
•
Poor sensor placement.
•
Motion at the sensor site.
•
Electrical interference.

Figure 2-4. Noisy plethysmographic waveform

If three easily identifiable passes of a "typical" waveform do not occur,
•
Make sure the sensor's detector is flush with the sensor site (for sensor
application, see the instructions for the sensor you are using).
•
Make sure the light source and detector are directly opposite each other.
•
Select a site where the distance between the light source and the detector is less.
•
Make sure the patient site is stable; minimize movement of the sensor site.
•
Massage the sensor site with a 70% isopropyl alcohol pad or rubefacient cream
(10-30% methyl salicylate and 2-10% menthol) for 20-30 seconds. Strong
vasodilator creams, such as nitroglycerin paste, are not recommended.
•
If possible, remove electrical noise sources such as electrosurgery or
electrical/electronic devices (e.g., fans). If these solutions are not possible,
operate the oximeter on battery power, or try plugging the oximeter into a
different electrical outlet.
•
If artificial nails or excessive fingernail polish are present, select another site
or remove the polish/artificial nails.
2/Setup and Operations
2-9