GE Marquette Responder 3000, Руководство оператора

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Capnometry (etCO
2
)
227 490 02-C Marquette Responder® 3000 55
Safety Information
Warning
Observe the following information to prevent
erroneous CO
2
measurements. Inappropriate
therapeutic measures based on erroneous readings
may cause severe damage or the patient's death.
-
etCO
2
measurement is not suitable for patients
under 3 years of age or patients weighing less
than 10 kg.
-
The sensor may give inaccurate readings
when used on patients with a respiration rate
greater than or equal to 60 breaths per min-
ute.
-
etCO
2
measurement is not suitable for quan-
titative measurement during intraoperative
anesthesia or in the ICU environment.
-
etCO
2
readings should be considered as addi-
tional parameters in the assessment of a pa-
tient's condition. They should always be seen
in the context of other clinical signs and
symptoms.
-
Do not use the sensor on patients with small
tidal volumes because the dead space volume
of the airway adapter is about 5 cc. This could
affect the ventilation. If the tidal volume is too
low, the sensor may not be able to detect the
patient's inspiration and expiration.
-
Do not touch or wipe the window of the airway
adapter to avoid damage. If the window is
damaged, water droplets may adhere to the
surface which could affect the performance
and accuracy of the sensor.
-
The airway adapter can be continuously used
for about 24 hours under normal operating
conditions. If blood, sputum or phlegm has
entered the airway adapter, discard the airway
adapter and use a new one.
-
Do not measure the etCO
2
concentration on a
patient undergoing an MRI examination. This
could cause the sensor to give inaccurate
readings.
-
High concentrations of nitrous oxide (N
2
O) or
halogenated anesthetic agents can cause the
sensor to give inaccurate readings.
-
The sensor may give lower readings when
used in a low pressure environment (do not
use in airplane).
-
Do not allow condensation to develop in the
sensor, condensation can attenuate the signal,
resulting in degraded performance.
-
The sensor may give erroneous readings when
exposed to rapid temperature changes.
-
The readings may be inaccurate when CO
2
is
present in the airway adapter during inspira-
tion. The displayed etCO
2
values are based on
the assumption that the inspired air is free of
CO
2
.
The readings obtained during mouth-to-
mouth resuscitation may therefore be inaccu-
rate. The same is true if Jackson-Rees and
Mapleson-D ventilators are used.
-
The readings may be inaccurate in patients
with high or irregular respiration rate (indi-
cator in sensor goes briefly off).
-
The measurement accuracy depends on the
altitude of the measurement site. It decreases
with increasing altitude (Figure 10-6).
Note
In most cases the endtidal CO
2
value (etCO
2
) is
below the arterial CO
2
partial pressure (paCO
2
)
determined by blood-gas analysis (see Literature).
Possible clinical causes are:
- dead-space ventilation, ventilation/perfusion
mismatch
- decreased cardiac output
- alveolar shunts
- incomplete emptying of the alveoli.