Should ancillary brain blood flow analyses play a larger role in the neurological determination of death?

We present two patients who regained spontaneous respiration following clinical neurological determination of death (NDD) while ancillary radiological imaging demonstrated brain blood flow.

A 26-yr-old male with chronic otitis media presented with a Glasgow Coma Scale (GCS) score of 3 and fixed 7-mm pupils. Computed tomography demonstrated right-sided mastoiditis and a temporal lobe abscess associated with uncal herniation. The patient was diagnosed brain dead seven-hr later when motor responses and brainstem reflexes were absent and his apnea test was positive. Approximately 28-hr after NDD, during post-declaration organ resuscitation, the patient regained spontaneous respiration and magnetic resonance imaging revealed brain blood flow. Spontaneous respirations persisted for five-days before cardiovascular collapse occurred. In the second case, a 50-yr-old female presented with a GCS score of 3 and fixed 6-mm pupils following a traumatic brain injury and a five-minute cardiac arrest. The patient was deemed clinically brain dead six-hr later when physical examination revealed absent motor responses and brainstem reflexes and her apnea test was positive. As confirmation of brain death, a cerebral radionuclide angiogram was performed, which surprisingly revealed intracranial arterial flow. During organ resuscitation, 11-hr after NDD, the patient regained spontaneous respiration. She expired hours after family decision to withdraw treatment.

For both patients, several unrecognized confounding factors for NDD were present. These cases illustrate the difficulties encountered by experienced clinicians in determining brain death using clinical criteria alone, and they suggest that more routine use of ancillary brain blood flow analyses should be recommended.