Brain Stem Death - Prognosis and Management

Prognosis and Management

With due regard for the cause of the coma, and the rapidity of its onset, testing for the purpose of diagnosing death on brain stem death grounds may be delayed beyond the stage where brain stem reflexes may be absent only temporarily – because the cerebral blood flow is inadequate to support synaptic function although there is still sufficient blood flow to keep brain cells alive and capable of recovery. There has recently been renewed interest in the possibility of neuronal protection during this phase by use of moderate hypothermia and by correction of the neuroendocrine abnormalities commonly seen in this early stage.

Published studies of patients meeting the criteria for brain stem death or whole brain death – the American standard which includes brain stem death diagnosed by similar means – record that even if ventilation is continued after diagnosis, the heart stops beating within only a few hours or days. However, there have been some very long-term survivals and it is noteworthy that expert management can maintain the bodily functions of pregnant ‘brain dead’ women for long enough to bring them to term.

The management of patients pronounced dead on meeting the brain stem death criteria depends upon the reason for diagnosing death on that basis. If the intent is to take organs from the body for transplantation, the ventilator is reconnected and life-support measures are continued, perhaps intensified, with the addition of procedures designed to protect the wanted organs until they can be removed. Otherwise, the ventilator is left disconnected on confirmation of the lack of respiratory centre response (the last test). In the second case, the diagnostic procedure may be less rigorous, e.g. omission of the caloric test which could be intensely, and unnecessarily, distressing.