User's Manual

Ultraview Care Network
22-10
Operation
CO
2
, N
2
O, and anesthetic agents are measured by drawing a sample gas stream
into the measuring chamber. The absorption of different infrared light wavelengths
is measured here. These measurements are compared to a zero concentration
light level to calculate the different gas concentrations.
Oxygen concentration is measured using the micro-fuel cell sensing technology.
During the sensing process, the oxygen molecules in the sampled gas diffuse
through the sensing membrane and become reduced at the sensing electrode,
creating a current signal. The current signal is proportional to the oxygen partial
pressure in the sampled gas. The fast response of the oxygen measurement is
achieved by combining a unique design of the pneumatic sampling system, fast
sensing membrane, and state-of-the-art signal processing electronics. Because
this method of measurement has a fast response time, inspired and expired
values of O
2
can be reported. This method of O
2
measurement requires periodic
replacement of the sensor. The user must perform routine calibration checks to
determine when replacement is needed. Refer to Initiating a Calibration on page
22-19 for further details.
The analyzer uses a side-stream sampling technique to acquire respiratory gases
from an endotracheal tube, nasal cannula, or mask. A constant-flow vacuum
system maintains the flow rate through the sample line.
The analyzer is equipped with an external water trap to prevent humidity, water
drops, and patient secretions from contaminating the unit or affecting the accuracy
of the gas measurements. The water trap collects water drops that condense in
the sample line. A “Water Trap Full” indicator warns you that the water trap should
be replaced. The analyzer is also equipped with a filter as a second line of
defense in case the water trap overflows or nebulized drugs are accidently drawn
into the sample line. After the gas sample passes through the water trap and filter,
it passes through a Nafion tube that is inside the analyzer. This helps to equalize
the humidity of the gas sample so that it is close to the humidity of ambient air.
WARNING:
• If any halogenated anesthetic agent other than halothane,
enflurane, isoflurane, sevoflurane, or desflurane is present,
it will be misidentified and/or will interfere with the reported
anesthetic agent concentrations.
CAUTION:
• When administering anesthetic agents, incorrect agent
identification may occur when a mixture of two or more
anesthetic agents occurs in the sample circuit.
• Always verify your anesthetic vaporizer setting when
administering anesthetic agents.