Operator's Manual

Table Of Contents
Radical-7 Chapter 1: Technology Overview
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1. Oxyhemoglobin (oxygenated blood) and deoxyhemoglobin (non-
oxygenated blood) differ in their absorption of red and infrared
light (spectrophotometry).
2. The amount of arterial blood in tissue changes with your pulse
(photoplethysmography). Therefore, the amount of light
absorbed by the varying quantities of arterial blood changes as
well.
Successful Monitoring for SpO2, PR, and PI
Stability of the SpO
2
readings may be a good indicator of signal validity.
Although stability is a relative term, experience will provide a good
feeling for changes that are artifactual or physiological and the speed,
timing, and behavior of each.
The stability of the readings over time is affected by the averaging mode
being used. The longer the averaging time, the more stable the readings
tend to become. This is due to a dampened response as the signal is
averaged over a longer period of time than during shorter averaging
times. However, longer averaging times delay the response of the
oximeter and reduce the measured variations of SpO
2
and pulse rate.
Functional Oxygen Saturation (SpO2)
The Radical-7 is calibrated to measure and display functional oxygen
saturation (SpO2): the amount of oxyhemoglobin expressed as a
percentage of the hemoglobin that is available to transport oxygen.
Note: Dyshemoglobins are not capable of transporting oxygen, but are
recognized as oxygenated hemoglobins by conventional pulse oximetry.