Cardinal Health Alaris 8000 Series, Directions For Use Manual

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General Information
Alaris
®
System Directions for Use
SpO
2
Modules Section
NOTE:
€
Exposure to excessive illumination can be corrected by
covering the sensor with a dark or opaque material.
Measurement Accuracy (Continued)
The loss of a pulse signal can occur in any of the following
situations:
• Sensor is too tight.
• Exposure to excessive illumination; such as, a surgical
lamp (especially one with a xenon light source), bilirubin
lamp, fluorescent light, infrared heating lamp or direct
sunlight.
• Sensor placed on an extremity with a blood pressure cuff,
arterial catheter, intravascular line or other causes of
insufficient perfusion.
• Patient has hypotension, severe vasoconstriction, severe
anemia or hypothermia, is in cardiac arrest or is in shock.
• There is an arterial occlusion proximal to sensor.
• Placement is too close to electrosurgery equipment.
Principle of Operation
The operation of the
S
p
O
2
Module (
8210
Series) is based on
the principles of pulse oximetry. Oxyhemoglobin and
deoxyhemoglobin differ in their absorption of red and infrared
light (spectrophotometry). The volume of arterial blood in
tissue and the light absorbed by the blood changes during the
pulse (plethysmography). A pulse oximeter determines
S
p
O
2
by passing red and infrared light into an arteriolar bed and
measuring changes in light absorption during the pulsatile
cycle. Red and infrared low-voltage light-emitting diodes
(
LED
) in the oximetry sensor serve as light sources; a photo
diode serves as the photo detector.
Because oxyhemoglobin and deoxyhemoglobin differ in light
absorption, the amount of red and infrared light absorbed by
8210 Series
(8210)