Role of end-tidal $CO_2$ monitoring in patients intubated and resuscitated in the emergency department

Abstract

We examined the reliability of end-tidal $CO_2$ ($ETCO_2$ ) level in predicting mortality after endotracheal intubation in emergency situations. Methods: In this prospective study, the reliability of $ETCO_2$ monitoring in the emergency setting as a useful predictor of outcome was investigated in 36 adult patients with pending cardiopulmonary collapse. The cardiopulmonary resuscitation (CPR) procedure was performed as usual and the cardiac rhythm, arterial $O_2$ saturation, non- invasive blood pressure and $ETCO_2$ levels were continuously monitored in all the patients. Results: Patients with an $ETCO_2$ concentration below 0.5% had significantly lower rates of survival. The sensitivity and specificity values of end-tidal $CO_2$ levels equal to or greater than 0.5% in predicting survival were 100% and 42.8%, respectively. None of the 8 patients with levels below 0.5% survived. An end-tidal $CO_2$ concentration level of 0.5% served to discriminate between survivors and non-survivors. Conclusions: These results suggest that the initial $ETCO_2$ concentration can be an important predictor of outcome, especially with regard to mortality in patients undergoing endotracheal intubation.