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Updated: Sep 9, 2026

Expired CO2 Measurement in Intubated or Spontaneously Breathing Patients from the Emergency Department
Published on: January 30, 2011
The history of pH and blood gas analysis
1Department of Anesthesia, Northwestern University Medical School, Chicago, Illinois, USA.
Abstract:
It is difficult for today's clinician to appreciate the rapid evolution of technology relevant to pH and blood gas measurements. Discovery of the scientific foundations took three centuries, whereas development of practical methods for clinical application took only three decades from the realization of their potential clinical importance. All indications are that advancement will continue at the same pace for the next several decades.
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