9
How Does
the Activ8rlives
Pulse Oximeter3 Work?
The
Activ8rlives
Pulse Oximeter3
is a non
-
invasive wireless method allowing the monitoring of the saturation of
oxygen of the haemoglobin in your blood.
A sensor is placed on a thin part of your body, such as your fingertip. Light of two wavelengths is passed through
the finger to a photodetector. The changing absorbance at each of the two wavelengths (red 660nm and infrared
905nm) is measured, allowing it to determine the absorbances due to the pulsing arterial blood alone (the blood
flowing from the heart and lungs), and excludes venous blood (the blood returning to the heart and lungs), skin,
bone, muscle, fat, and fingernails.
A blood
-
oxygen monitor displays the percentage of arterial haemoglobin (Hb) in the oxyhaemoglobin (HbO
2
).
Acceptable normal range from 95
-
99 percent (%). In those with a respiratory condition, they would expect values
between 88
-
94%. For a patient breathing room air at sea level, an estimate of arterial oxygen saturation levels
(pO
2
) can be made from the blood
-
oxygen monitor SpO
2
reading.
The monitored signal fluctuates in time with the heart beat because the arterial blood vessels expand and
contract with each heart beat. By examining only the varying part of the absorption spectrum (essentially
subtracting minimum absorption from peak absorption), a monitor can ignore other tissues or nail polish (though
black nail polish or false fingernails tend to distort readings) and discern only the absorption caused by arterial
blood. Detecting a pulse is therefore essential to the operation of the
Activ8rlives
Pulse Oximeter3
and it will not
function if there isn
’
t one. See
Page 19
for instructions on obtaining accurate and consistent readings.
Your
Activ8rlives
Pulse Oximeter3
will give you two important pieces of information: your oxygen saturation
levels (SpO
2
) and your pulse rate in beats per minute (bpm).
If in doubt about your health, please consult your medical team first and follow their advice closely.
