Preserved brain morphology after controlled automated reperfusion of the whole body following normothermic circulatory arrest time of up to 20 minutes

OBJECTIVES: Clinical outcomes following cardiac arrest (CA) and resuscitation remain a cause for concern. The use of Controlled Automated Reperfusion of the whoLe body (CARL) confers superior neurological outcome even after extended periods of CA. We aimed at investigating clinical outcome and brain morphology preservation when employing CARL following CA periods of 20 min. METHODS: Twenty-eight pigs were allocated to four extracorporeal circulation treatment strategies; seven others served as magnetic resonance imaging (MRI) controls. In prompt cardiopulmonary resuscitation (CPR; n = 6), induced circulatory arrest was followed immediately by open cardiac massage of 15 min, thereafter by CARL for 60 min. In delayed CPR (n = 6), induced CA was maintained for 15 min, after that open cardiac massage of 10 min duration was performed prior to extracorporeal CPR (ECPR) of 60 min. Induced CA times of 15 min in the ECPR 15' group (n = 6) and CA of 20 min in the CARL 20' group (n = 10) were followed by ECPR of 60 min and CARL of 60 min, respectively, without prior CPR. Daily neurological deficit scoring (NDS) up to the seventh day, markers of cellular injury alanine transaminase (ALT), aspartate transaminase (AST) and neuron-specific enolase (NSE) and brain MRI were performed. RESULTS: /s (58); U = 9; P = 0.0164] in the CARL 20' group showed higher signal intensities compared with controls. In delayed CPR, corresponding regions of interest on early apparent diffusion coefficient images showed a restricted diffusion. CONCLUSIONS: In our experimental animal model of CA, CARL results in satisfactory survival at CA periods of 20 min despite detected enzyme and morphological changes. These changes did not translate to clinical neurological deficits.