End-tidal carbon dioxide monitoring in emergency medicine, Part 2: Clinical applications.

End-tidal carbon dioxide (PetCO2) monitoring is becoming more common in both the ED and the out-of-hospital setting. Its main use has been as an aid when confirming endotracheal intubation. Other uses in the ED include monitoring CPR efforts and monitoring the ventilatory and hemodynamic status of intubated and nonintubated patients. In addition, future uses may include using PetCO2 as an adjunct when monitoring the status of asthma treatment, when making the diagnosis of pulmonary embolism, and when measuring cardiac output noninvasively. This article reviews these specific uses of PetCO2 monitoring in emergency medicine.