Brain dead or not? CT angiogram yielding false-negative result on brain death confirmation

Abstract

We describe a case of severe traumatic brain injury with multiple facial and skull fractures where CT angiogram (CTA) failed to yield a definite result of brain death as an ancillary test. A 28-year-old man was admitted following a road traffic accident with a Glasgow Coma Score (GCS) of 3/15 and fixed pupils. CT brain revealed uncal herniation and diffuse cerebral oedema with associated multiple facial and skull fractures. 72 h later, his clinical condition remained the same with high intracranial pressure refractory to medical management. Clinical confirmation on brain death was not feasible owing to facial injuries. A CTA, performed to determine brain perfusion, yielded a ‘false-negative’ result. Skull fractures have possibly led to venous prominence in the cortical and deep venous drainage system. This point needs to be borne in mind while considering CTA as an ancillary test to confirm brain death.

Ancillary Testing in Brain Death

“…Skull defects or decompressive craniectomy may prevent complete cessation of intracranial blood flow, even when patients otherwise meet clinical criteria for brain death. 70,71 Two systematic reviews have assessed the diagnostic accuracy of CT angiography in the confirmation of brain death. 68,69 Taylor and colleagues identified 10 studies and reported a sensitivity of 84% in relation to the diagnosis of brain death by physical examination and apnea testing.…”

Avaliação Dos Critérios Exigidos Para a Realização Do Termo De Declaração De Morte Encefálica Em Pacientes Submetidos Ao Diagnóstico De Morte Encefálica E Caracterização Do Perfil Dos Potenciais Doadores Em Um Hospital Em São Paulo

“…19 Os exames complementares comprobatórios mais confiáveis e aceitos de morte encefálica, atualmente, são os que demonstram a total ausência de perfusão sanguínea encefálica, podendo ser demonstrada por angiografia, tomografia computadorizada por emissão de fóton único ou Doppler Transcraniano (DTC). 20 Apesar de poderem ser utilizados outros exames, como por exemplo, os que confirmem a perda da atividade elétrica (eletroencefalografia ou potenciais evocados somatossensoriais) 21 ou atividade metabólica cerebral (PET ou extração cerebral de oxigênio). 8 Neste estudo, o DTC foi utilizado com a mesma frequência que o Eletroencefalograma (EEG).…”

Acurácia da angiografia por tomografia computadorizada no diagnóstico de morte encefálica

“…However, it has been neglected by others because of controversial results 93,165,170,[182][183][184] .…”