Predicting the lack of ROSC during pre-hospital CPR: should an end-tidal CO2 of 1.3 kPa be used as a cut-off value?

AIM: The aim of this study was to investigate if an initial ETCO2 value at or below 1.3 kPa can be used as a cut-off value for whether return of spontaneous circulation during pre-hospital cardio-pulmonary resuscitation is achievable or not.

MATERIALS AND METHODS: We prospectively registered data according to the Utstein-style template for reporting data from pre-hospital advanced airway management from February 1st 2011 to October 31st 2012. Included were consecutive patients at all ages with pre-hospital cardiac arrest treated by eight anaesthesiologist-staffed pre-hospital critical care teams in the Central Denmark Region.

RESULTS: We registered data from 595 cardiac arrest patients; in 60.2% (n=358) of these cases the pre-hospital critical care teams performed pre-hospital advanced airway management beyond bag-mask ventilation. An initial end-tidal CO2 measurement following pre-hospital advanced airway management were available in 75.7% (n=271) of these 358 cases. We identified 22 patients, who had an initial end-tidal CO2 at or below 1.3 kPa. Four of these patients achieved return of spontaneous circulation.

CONCLUSION: Our results indicates that an initial end-tidal CO2 at or below 1.3 kPa during pre-hospital CPR should not be used as a cut-off value for the achievability of return of spontaneous circulation.