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Updated: Sep 20, 2026

Expired CO2 Measurement in Intubated or Spontaneously Breathing Patients from the Emergency Department
Published on: January 29, 2011
Continuous end-tidal carbon dioxide monitoring during normofrequent jet-ventilation
L F Bach1, H Wanner-Olsen, B N Andersen
1Department of Anaesthesiology, Viborg Hospital, Denmark.
Background:
Continuous end-tidal carbon dioxide (ETCO2) monitoring during normofrequent jet-ventilation (NFJV) has not previously been successful and no correspondence between ETCO2 and arterial carbon dioxide (PaCO2) demonstrated.
Methods:
During NFJV jet-ventilation in 19 healthy volunteers, continuous ETCO2 was measured and compared to PaCO2 values. The original ETCO2 sampling line from our Datex CO2 measuring equipment was placed longitudinally against a suction catheter and both were wrapped with aluminium foil. They were placed 4-5 cm above the carina and the position was verified with a fiberoptic bronchoscope.
Results:
The correlation between methods gave a Pearson's product moment correlation (r value) of 0.836, significant at the P < 0.001 level, indicating a close correlation between methods. A difference against mean scatter diagram confirmed that ETCO2 and PaCO2 measurements are of equal value in monitoring healthy patients during NFJV.
Conclusion:
A valuable method of continuous ETCO2 monitoring during NFJV is presented.
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