Related Experiment Video
Updated: Feb 13, 2026

Endotracheal Intubation Using a Flexible Intubation Endoscope as a Standardized Model for Safe Airway Management in Swine
Published on: August 25, 2022
Detection of exhaled carbon dioxide following intubation during resuscitation at delivery
Katie A Hunt1,2, Yosuke Yamada1,2, Vadivelam Murthy1,2
1MRC & Asthma UK Centre in Allergic Mechanisms in Asthma, King's College London, London, UK.
Objectives:
End tidal carbon dioxide (ETCO2) monitoring can facilitate identification of successful intubation. The aims of this study were to determine the time to detect ETCO2 following intubation during resuscitation of infants born prematurely and whether it differed according to maturity at birth or the Apgar scores (as a measure of the infant's condition after birth).
Design:
Analysis of recordings of respiratory function monitoring.
Setting:
Two tertiary perinatal centres.
Patients:
Sixty-four infants, with median gestational age of 27 (range 23-34)weeks.
Interventions:
Respiratory function monitoring during resuscitation in the delivery suite.
Main Outcome Measures:
The time following intubation for ETCO2 levels to be initially detected and to reach 4 mm Hg and 15 mm Hg.
Results:
The median time for initial detection of ETCO2 following intubation was 3.7 (range 0-44) s, which was significantly shorter than the median time for ETCO2 to reach 4 mm Hg (5.3 (range 0-727) s) and to reach 15 mm Hg (8.1 (range 0-827) s) (both P<0.001). There were significant correlations between the time for ETCO2 to reach 4 mm Hg (r=-0.44, P>0.001) and 15 mm Hg (r=-0.48, P<0.001) and gestational age but not with the Apgar scores.
Conclusions:
The time for ETCO2 to be detected following intubation in the delivery suite is variable emphasising the importance of using clinical indicators to assess correct endotracheal tube position in addition to ETCO2 monitoring. Capnography is likely to detect ETCO2 faster than colorimetric devices.
Related Concept Videos
Carbon-dioxide Fixation
Carbon Dioxide Transport in the Blood
Forms of CO2 Transport
1. Dissolved in plasma: A small percentage (7-10%) of CO2 is transported and dissolved directly in the plasma.
2. Carbaminohemoglobin: Just over 20% of CO2 is chemically bound to...
Pulmonary Cycle: Exhalation
The Carbon Cycle
Cardiopulmonary Resuscitation I: Adult
Carbon Skeletons

