End-tidal carbon dioxide concentration during cardiopulmonary resuscitation in patients with pre-hospital cardiac arrest

: This study was done to clarify whether end-tidal carbon dioxide (ETCO2) concentration is an effective monitor as an indicator of survival and prognosis of patients who arrived with cardiac arrest. We measured ETCO2 concentration in 30 patients with pre-hospital cardiac arrest during cardiopulmonary resuscitation (CPR). Six patients were resuscitated successfully and the others were not. The values of ETCO2 of the resuscitated patients, at the time of starting advanced life support were varied from 0 to 4.5% (mean 1.4%), which were not different from the values in patients who were not resuscitated (mean 0.87%). In 13 patients who were not resuscitated, the initial values of ETCO2 during CPR were below 1.0%, whereas the other 11 patients showed high ETCO2 values (above 1.5%), which were dependent on the degree of chest compression. This suggests that ETCO2 monitoring during cardiopulmonary resuscitation is a good non-invasive indicator to evaluate the efficacy of chest compression itself, but its initial values during CPR are not correlated with success of resuscitation in patients with pre-hospital cardiac arrest.