A 10 min “no-touch” time – is it enough in DCD? A DCD Animal Study

Summary Donation after cardiac death (DCD) is under investigation because of the lack of human donor organs. Required times of cardiac arrest vary between 75 s and 27 min until the declaration of the patients’ death worldwide. The aim of this study was to investigate brain death in pigs after different times of cardiac arrest with subsequent cardiopulmonary resuscitation (CPR) as a DCD paradigm. DCD was simulated in 20 pigs after direct electrical induction of ventricular fibrillation. The “no-touch” time varied from 2 min up to 10 min; then 30 min of CPR were performed. Brain death was determined by established clinical and electrophysiological criteria. In all animals with cardiac arrest of at least 6 min, a persistent loss of brainstem reflexes and no reappearance of bioelectric brain activity occurred. Reappearance of EEG activity was found until 4.5 min of cardiac arrest and subsequent CPR. Brainstem reflexes were detectable until 5 min of cardiac arrest and subsequent CPR. According to our experiments, the suggestion of 10 min of cardiac arrest being equivalent to brain death exceeds the minimum time after which clinical and electrophysiological criteria of brain death are fulfilled. Therefore shorter “no-touch” times might be ethically acceptable to reduce warm ischemia time.