Pulse Oximetry

The pulse oximeter is a small, clip-like device, and is a noninvasive test that measures the oxygen saturation level of your blood. It can rapidly detect even the smallest changes in oxygen levels in the body.

A pulse oximeter can be used on any finger but the National Health Service (NHS) recommends the middle or index finger for the best readings

A wireless pulse oximeter is like a fingertip oximeter that is helping to simplify the measurement of oxygen saturation, pulse and heart rate. It is lightweight and can make use of Bluetooth. A wired pulse oximeter makes use of wires and cables to function effectively, and once the probe wire becomes dislodged or gets entangled, it may require replacement

Pulse oximetry is useful in both inpatient and outpatient environments. 

These are the steps to take a reading with a pulse oximeter;

• Remove any jewellery or fingernail polish on your finger if you will be making use of finger
• Make sure your hand is warm, relaxed, and below heart level, for the finger, you will be attaching the device on
• Put the oximeter on your finger, earlobe, or toe.
• Keep it on for as long as it is needed to monitor your pulse and oxygen saturation.
• Then you can unplug the device once the test is over.
  
  The pulse oximetry process displays small beams of light which pass through the blood in your finger, measuring the amount of oxygen. This is a painless process. The pulse oximeter will therefore be able to tell you your oxygen saturation levels along with your heart rate."

Yes

Pediatric pulse oximeters are designed to be able to read oxygen and heart rate from primarily the toes or fingers of neonates (under 8 lbs.), infants (5 to 45 lbs.) and children (under 75 lbs.)

Yes it does

Pulse oximeters are triggered to alert nurses of a possible hypoxemic situation when SpO2 falls below a threshold for a pre-specified time

Blue, green, black, and brown nail polish appear to interfere or affect most with pulse oximeter readings.

Blue and green colours produced greater decreases than purple and red. While the black produced an intermediate decrease. Not all nail polishes can absorb light at the different wavelengths used by the pulse oximeter.