One comprehensive clinical neurologic examination is sufficient to declare brain death

Objective: To fill the evidence gap on the value of a single (SBD) or dual brain death (DBD) exam by providing data on irreversibility of brain function, organ donation consent and transplantation  

Methods: 12-year tertiary hospital and organ procurement organization data on brain death (BD) were combined and outcomes, including consent rate for organ donation and organs recovered and transplanted after SBD and DBD were compared after multiple adjustments for co-variates 

Results: two-hundred sixty-six patients were declared BD, 122 after SBD and 144 after DBD. Time from event to BD declaration was longer by an average of 20.9 hours after DBD (p=0.003). Seventy-five (73%) families of patients with SBD and 86 (72%) with DBD consented for organ donation (p=0.79). The number of BD exams was not a predictor for consent. No patient regained brain function during the periods following BD. Patients with SBD were more likely to have at least one lung transplanted (p = 0.033). The number of organs transplanted was associated with the number of exams [beta coefficient, (95% CI) -0.5 (-0.97 to -0.02), p=0.044], along with age (for 5 year increase, -0.36 (-0.43 to -0.29), p<0.001) and PaO2 level (for 10 mmHg increase, 0.026 (0.008 to 0.044), p=0.005) and decreased as the elapsed time to BD declaration increased (p=0.019). 

Conclusions:  A single neurologic examination to determine brain death is sufficient in patients with non-anoxic catastrophic brain injuries. A second examination is without additional yield in this group and its delay reduces the number of organs transplanted.