Deferred consent in emergency intensive care research: what if the patient dies early? Use the data or not?

Respect for individual autonomy, expressed in the concept of informed consent, is the basic ethical principle in research with humans. Many ICU patients are unable to give consent as a consequence of mental incapacity, and this can be further complicated in emergency situations, in which treatment needs to be initiated without delay. Various approaches are used as surrogate to subject consent: waiver of consent, consent by an independent physician and deferred consent. Deferred consent involves randomization at the investigator's discretion according to criteria that have been explicit during ethical review of the protocol, followed by the request for patient's (deferred subject consent) or representative's (deferred proxy consent) informed consent in a later phase. Several emergency trials have used deferred consent [ 1 , 2 , 3 , 4 ].