Aim: To determine how long a period of having had no cardiopulmonary-resuscitation (CPR) (delay time) is considered to result in subsequent futile efforts at resuscitation., Methods: In 2007 a survey was mailed to all 77 paediatric intensivists in Canada. Three scenarios of witnessed cardiac arrest were presented: out-of-hospital, in-hospital, and in-hospital with extracorporeal-CPR (E-CPR). Each scenario asked what delay time would make attempts at resuscitation futile for survival to hospital discharge, and for survival to hospital discharge in a better than vegetative state. Comparisons of median [inter-quartile range] used Wilcoxon-signed-rank or Friedman tests with Bonferroni corrections., Results: The response rate was 49/77 (64%). The delay time was significantly different between rhythms within all scenarios (p<.001); and was significantly shorter for survival than for better than vegetative survival (p<.006) except when E-CPR was to be used. The delay time was not significantly different between the in-hospital and out-of-hospital scenario with the same rhythms (p>.01). The delay time was significantly shorter in scenarios with asystole versus pulseless electrical activity with (p=.010) or without (p<.001) an arterial line with absent pulsation. In out-of-hospital arrest, the delay time for survival varied from 15 [10-20]min for asystole to 20 [15-20]min for pulseless electrical activity. In in-hospital scenarios, the delay time for survival varied from 10 [10-20]min for asystole, to 15 [10-20]min for most other rhythms., Conclusion: A delay time of 15 [10-20] (range 5-30)min was considered futile for survival. This has implications for pronouncing death in donation after cardiac death.