Related Experiment Video
Updated: Aug 29, 2026

Expired CO2 Measurement in Intubated or Spontaneously Breathing Patients from the Emergency Department
Published on: January 29, 2011
End-tidal CO2 as a function of tidal volume in mechanically ventilated infants
Karen J Greer1, Winslade A Bowen, Alfred N Krauss
1Perinatology Center, Department of Pediatrics, New York Presbyterian Hospital-Weill Medical College of Cornell University, New York, New York 10021, USA.
Objective:
To test the hypothesis that end-tidal CO(2) (PETCO(2)) varies with tidal volume (Vt) in preterm infants.
Design:
Intervention study, nonrandomized trial.
Setting:
Neonatal ICU, regional referral center.
Subjects:
29 preterm infants 790 to 2135 g in weight requiring mechanical ventilation studied on 73 occasions.
Intervention:
Measurement of PETCO(2) during variations of Vt.
Measurement:
Statistical correlation of PETCO(2) to Vt.
Result:
PETCO(2) is minimal when Vt is either too low or too high.
Conclusion:
Vt, through its effect on dead space/Vt (Vd/Vt) ratios and arterial-alveolar CO(2) differences, has a significant effect on PETCO(2). Observation of PETCO(2) across a range of Vt can be used to select an appropriate Vt for preterm infants requiring mechanical ventilation.
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