Covidien Nellcor GR101704, Service Manual

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Patient Conditions
Service Manual 8-3
High ambient light sources such as surgical lights (especially those with a xenon
light source), bilirubin lamps, fluorescent lights, infrared heating lamps, and
direct sunlight can interfere with the performance of a recommended sensor.
To prevent interference from ambient light, ensure the recommended sensor
is properly applied, and cover the sensor with opaque material.
If patient movement presents a problem, try one or more of the following remedies
to correct the problem.
•
Verify the recommended sensor is properly and securely applied.
•
Move the sensor to a less active site.
•
Use an adhesive sensor that improves patient skin contact.
•
Use a new sensor with fresh adhesive backing.
•
Keep the patient still, if possible.
If poor perfusion affects performance, consider using the Nellcor™ forehead
SpO
2
sensor (Max-Fast), which provides superior detection in the presence of
vasoconstriction. Nellcor™ forehead SpO
2
sensors work particularly well on
supine patients and mechanically ventilated patients. During low perfusion con-
ditions, Nellcor™ forehead SpO
2
sensors reflect changes to SpO
2
values up to
60 seconds earlier than digit sensors.
8.3
Patient Conditions
Application issues and certain patient conditions can affect the measurements
of the monitoring system and cause the loss of the pulse signal.
•
Anemia — Anemia causes decreased arterial oxygen content. Although SpO
2
readings may appear normal, an anemic patient may be hypoxic. Correcting
anemia can improve arterial oxygen content. The monitoring system may fail to
provide an SpO
2
reading if hemoglobin levels fall below 5 gm/dl.
•
Dysfunctional hemoglobins — Dysfunctional hemoglobins such as carboxyhe-
moglobin, methemoglobin, and sulfhemoglobin are unable to carry oxygen. SpO
2
readings may appear normal; however, a patient may be hypoxic because less
hemoglobin is available to carry oxygen. Further assessment beyond pulse oxime-
try is recommended.
•
Additional possible patient conditions may also influence measurements.
–
Poor peripheral perfusion
–
Excessive patient movement