End-Tidal Carbon Dioxide Impacts Brain and Kidney Injury in Experimental Extracorporeal Cardiopulmonary Resuscitation ECPR

PURPOSE:Extracorporeal membrane oxygenation assisted cardiopulmonary resuscitation (ECPR) is proposed for cardiac resuscitation in selected cases. End-tidal carbon dioxide (ETCO2) is easily obtained during conventional cardiopulmonary resuscitation (CPR). We hypothesized that the level of ETCO2 during CPR would reflect the degree of brain and kidney damage following ECPR in experimental refractory cardiac arrest. METHODS:Ventricular fibrillation was induced in 10 pigs, followed by mechanical CPR for 45 minutes and thereafter ECPR for 180 minutes. Blood- and urine-samples, physiologic parameters, and histopathology of brain and kidney were analysed. Animals were divided into Group High (GHigh) and Group Low (GLow) according to value of ETCO2 (10mmHg) at end of CPR. RESULTS:Carotid blood pressure and blood flow declined over time in both groups during CPR but was higher in GHigh. Coefficient of determination for ETCO2 and carotid blood flow was substantial (r = 0.62). The oxygen delivery index (DO2I) was higher for GHigh 444 (396–485) l/min/m as compared to GLow at 343 (327–384) l/min/m (p = 0.02) at the end of ECPR. Also, P-S100B were lower in GHigh, (p