ISEKI Hiroshi    Department   Research Institutes and Facilities, Research Institutes and Facilities    Position
Article types	Original article
Language	Japanese
Peer review	Peer reviewed
Title	Usefulness of a Novel Flow-through Capnometer for Non-intubated Spontaneously Breathing Patients
Domestic / Foregin	Domestic
Volume, Issue, Page	pp.103-110
Publication date	2008/03
Summary	Capnometers are recently being applied to non-intubated, spontaneously breathing patients. Conventional sidestream capnometers use a cannula to aspirate sample gas so the expired gas gets diluted with ambient air during oral breathing and reduced ventilation. This causes inaccurate partial pressure of end-tidal carbon dioxide (etCO_2) measurement We developed a flow-through capnometer, cap-ONE^[○!R], for non-intubated patients which needs no aspiration. The accuracy of capnogram and etCO_2 was compared for the cap-ONE^[○!R] and conventional sidestream capnometers. In spontaneous breathing model experiments, capnograms of nasal and oral breathing in normal and reduced ventilation were compared to a reference capnogram. In these experiments, the capnograms and etCO_2 from the cap-ONE^[○!R] during normal and reduced ventilation coincided well with the reference capnogram but the sidestream capnometers showed distorted capnograms and inaccurate etCO_2 during reduced ventilation. In volunteer studies, a capnogram of nasal breathing was used as a reference. In these studies, capnograms with the cap-ONE^[○!R] during oral breathing were similar to those of nasal breathing, but capnograms with sidestream capnometer were distorted and etCO_2 was attenuated. The cap-ONE^[○!R] needed no aspiration so dilution of gas sample hardly occurred. We concluded that the cap-ONE^[○!R] could be useful for respiratory care of nonintubated patients.
Document No.	2008195951