Table 1.

Selection of knowledge gaps about determination of death by neurologic criteria

Medical and physiologic dimensions

1.1. What is the required time interval between injury or ROSC and DNC to ensure permanence of clinical findings?

1.2. What is the pattern of loss of brainstem reflexes? Is there a hierarchy among them in DNC?

1.3. How often does a second clinical exam differ from the first one in neonates and infants?

1.4. What is the time window for potential reversibility of clinical signs after decompressive craniectomy?

1.5. Does volumetric analysis by serial neuroimaging after decompressive craniectomy provide information that can impact the certainty of DNC?

1.6. What are the effects of drug confounders on DNC? What are their dose-dependent effects on DNC?

1.7. What are the sensitivity and specificity of quantitative pupillometry and traditional pupillary assessment?

1.8. What is the PaCO2 threshold generating respiratory drive depending on age, altitude, and baseline level?

1.9. Does exogenous CO2 administration during apnea testing increase the chance of completion?

1.10. Does the theoretical potential for hypercarbic cerebral vasodilatation related to the apnea test increase intracranial pressure?

1.11. What is the influence of applying positive pressure during apnea testing?

1.12. What are the characteristic differences between DNC patients with and without preserved hormonal function and temperature regulation?

Social and ethical dimensions

1.13. What are the family member perspectives of care in cases of DNC, their understanding of DNC, along with their bereavement needs and outcomes?

1.14. What are the impacts for relatives of witnessing the DNC assessment? Does it improve understanding and acceptance of DNC? Is it an additional source of psychological trauma?

DNC = determination of death by neurologic criteria; PaCO₂ = arterial partial pressure of carbon dioxide; ROSC = return of spontaneous circulation