BeneVision N22/N19 Patient Monitor Operator’s Manual 22 - 3
22.2 CO
2
Safety Information
• Remove the airway sample line from the patient’s airway while nebulized medications are being
delivered.
• Leakage in the breathing or sampling system may cause the displayed EtCO
2
values to be
significantly low. Always make sure that all components are securely connected.
• EtCO
2
values measured from the CO
2
module may differ from those of from the blood gas analysis.
• Route all tubing away from the patient’s throat to avoid strangulation.
• Inspect the airway adapter for a tight connection and proper operation before attaching it to the
patient.
• Squeezing or bending the sample line during the sidestream or microstream CO
2
measurement may
cause inaccurate CO
2
reading or no reading.
• Avoid mechanical shock to the sidestream CO
2
module configuring the paramagnetic oxygen
sensor.
22.3 CO
2
Measurement Limitations
The following factors may influence the measurement accuracy:
â– Leaks or internal venting of sampled gas
â– Mechanical shock
â– Cyclic pressure up to 10 kPa (100 cmH
2
O)
â– Other sources of interference, if any
Measurement accuracy may be affected by the breath rate and inspiration/expiration (I/E) ratio as follow:
â– EtCO
2
value is within specification for breath rate ≤ 60 rpm and I/E ratio ≤ 1:1;
â– EtCO
2
value is within specification for breath rate ≤ 30 rpm and I/E ratio ≤ 2:1.
Measurement accuracy is unspecified for breath rate larger than 60 bpm.
22.4 CO
2
Display
The CO
2
numeric and waveform area provide FiCO
2
measurement, EtCO
2
measurement, awRR measurement,
and a CO
2
waveform.
If your sidestream CO
2
module configures the oxygen sensor, O
2
waveform and paramters can be displayed as
follows:
(1) CO
2
waveform (2) Fraction of inspired CO
2
(FiCO
2
)
(3) End tidal CO
2
value (EtCO
2
) (4) Airway respiration rate (awRR)