Etablierung eines Modells zur Testung neurokognitiver Störungen nach kardiopulmonaler Reanimation bei Schweinen

OBJECTIVE: To test the feasibility of a neurocognitive test based on operant conditioning in a porcine model of cardiac arrest (CA) and cardiopulmonary resuscitation (CPR). Furthermore to characterize the influence of different durations of CA on cognitive performance and the accompanying neurohistopathological changes. METHODS: 17 male domestic pigs were included in this randomized controlled laboratory animal study. Animals were anesthetized and mechanically ventilated before arterial and pulmonary artery catheters were inserted. CA was induced electrically and after randomization of the animals in 2 groups (n=7/group) left untreated for either 5 or 8 mins CPR was performed with 100% oxygen and cardiac compressions at 100/min for 5 mins before defibrillation was attempted. 3 animals, treated identically with the exception that neither CA was induced nor CPR was performed, served as controls. MEASUREMENTS AND MAIN RESULTS: Hemodynamic variables as well as variables of gas exchange were measured at baseline and 10, 60, 120, 240 and 360 mins after CPR. Neurocognitive performance was evaluated using a test based on operant conditioning 5 days prior to and 4 days after CPR. On the fifth postoperative day animals were killed and the brains removed for histopathological evaluation of vulnerable brain regions. No noteworthy differences in hemodynamics or gas exchange were observed at baseline or after CPR. Animals exposed to 8 mins of untreated CA showed severe neurocognitive dysfunction being statistically significant on postoperative days 2 and 3 in comparison to animals exposed to 5 mins of CA or controls. Neurohistopathological evaluation revealed a significantly greater proportion of ischemically damaged neurons in the caudate nucleus and the putamen in subjected to 8 mins CA.CONCLUSION: Neurocognitive testing is feasible in this setting. Performance worsens with increasing ischemia time and is structurally associated with alterations in the caudate nucleus and the putamen