Non-invasive capnography allows continuous estimation of global cardiopulmonary function during resuscitation. The end-tidal CO2 concentration (ETCO2) is dependent on pulmonary blood flow and therefore on cardiac output. ETCO2 is an indirect parameter of the hemodynamic effectiveness of cardiac massage which correlates significantly with the critical hemodynamic determinants of successful resuscitation. Onset of cardiac arrest and successful restoration of spontaneous circulation are rapidly and surely recognizable. Capnography data during experimental porcine cardiac arrest and subsequent cardiopulmonary resuscitation are reported.