Primary brainstem death: a clinico-pathological study.

Abstract

SUMMARY A case of primary brainstem death in a man with surgically treated cerebellar haemorrhage is reported. Necropsy revealed extensive necrosis confined to the brainstem and cerebellum. The absence of diabetes insipidus and the persistence of electroencephalographic activity were the characteristic clinical features of the case. This differentiates the condition from so-called "whole brain death". Analysis of three further cases with acute vascular lesions of the brainstem or cerebellum, shown at necropsy, revealed that primary brainstem death with prolonged somatic survival can occur in specific circumstances after surgical intervension Brainstem death, as encountered in clinical practice, is nearly always a secondary phenomenon. It is the infratentorial repercussion of supratentorial events and has been described as the "physiological core" of "whole brain death" and as the main determinant of its clinical features and cardiac prognosis.' Lesions to the upper and lower brainstem which deprive it of its function may however produce the neurological entity of primary brainstem death.2 Judicial hanging (which ruptures the brainstem between pons and medulla without causing primary injury to the cerebral hemispheres) is the commonest cause of such a situation. There have been very few reports of "brain death" with prolonged somatic survival caused by lesions confined to the brainstem.3 4 We here report a necropsied case of cerebellar haemorrhage reproducing the clinical features of brainstem death and with somatic survival lasting 27 days. The pathological examination revealed necrosis confined to the brainstem and cerebellum.To determine the clinico-pathological characteristics of primary brainstem death in patients with infratentorial vascular lesions, necropsied cases with acute vascular lesions of the brainstem or cerebellum were then analysed. Case report A 47 year old hypertensive man was found lying on the floor. In 10 minutes, he became unresponsive. The blood pressure measured in a nearby hospital was 270/140 mmHg. Within an hour, he was intubated because spontaneous respiration ceased. The blood pressure fell at one stage to 80/52 mmHg. Three hours after the onset, he was transferred to the National Cardiovascular Center.On admission, he was deeply comatose. Pupillary light reactions were absent. The blood pressure was 146/106 mmHg. The extremities were flaccid. Routine laboratory examination was normal. Computed tomography (CT) of the brain revealed a massive haematoma (measuring 6 cm x 4 5 cm in its maximum diameters) involving the left cerebellar hemisphere and vermis with ventricular rupture. Dopamine and corticosteroid were administered for cardiovascular support. An emergency suboccipital craniotomy was performed 4 hours after the onset; the dura over the cerebellar hemispheres was so tense that the cerebellar tissue spouted out from the dural incision. Evacuation of the haematoma and extensive decompressive craniectomy were performed with opening of the foramen magnum and laminectomy of the fir...

Controversies in defining and determining death in critical care

“…11 The whole-brain and brainstem criteria of death are essentially identical, diverging only in the exceedingly rare instance of a massive brainstem infarct or haemorrhage that destroys the midbrain, pons and medulla but spares the cerebral hemispheres. 39,40 In such cases, a patient would be diagnosed as dead according to the brainstem criterion but might not be declared dead under the whole-brain criterion. In a modification of this formulation, Machado emphasized the brainstem basis for brain death as the irreversible loss of both dimensions of human consciousness: wakefulness and awareness.…”