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Updated: Aug 23, 2026

Expired CO2 Measurement in Intubated or Spontaneously Breathing Patients from the Emergency Department
Published on: January 29, 2011
Carbon dioxide monitoring and evidence-based practice - now you see it, now you don't
David Gattas1, Raj Ayer, Ganesh Suntharalingam
1Intensive Care Services, Royal Prince Alfred Hospital, Sydney, Australia. david.gattas@email.cs.nsw.gov.au
Abstract:
Carbon dioxide has been monitored in the body using a variety of technologies with a multitude of applications. The monitoring of this common physiologic variable in medicine is an illustrative example of the different levels of evidence that are required before any new health technology should establish itself in clinical practice. End-tidal capnography and sublingual capnometry are two examples of carbon dioxide monitoring that require very different levels of evidence before being disseminated widely. The former deserves its status as a basic standard based on observational data. The latter should be considered investigational until prospective controlled data supporting its use become available. Other applications of carbon dioxide monitoring are also discussed.
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