End-tidal carbon dioxide monitoring in the prehospital setting.

End-tidal carbon dioxide (ETCO2) monitoring is an exciting technology and has the potential to become a very useful tool in the prehospital setting. It can be useful in verifying endotracheal tube position and during cardiopulmonary resuscitation in the field. Recent reports of misplaced endotracheal tubes in the prehospital setting make it important to ensure that paramedics learn correct techniques of endotracheal intubation, and that they verify tube placement with an ETCO2 monitor. The new American Heart Association guidelines require secondary confirmation of proper tube placement in all patients by exhaled CO2 immediately after intubation and during transport. This article covers the terminology, the basic physiology, the technology (both colorimetric detectors and infrared capnometers), and the clinical applications of ETCO2 monitoring with special reference to the pediatric patient.