The persistent Vegetative State; Determination of death and Brain Death

Idara C. E.

Persistent Vegetative StatePatients in a PVS have no cortical

function, but have preserved brainstem function.

They are unconscious, with no awareness of their environment. They show no purposeful activity and cannot obey verbal commands.

The neurological basis for this lack of consciousness or awareness is extensive damage to the cerebral cortex, thalami or the connections between areas of the brain.

Determination of Death and Braindeath

Two methods of defining death are:• Cardiopulmonary criteria: Cessation of heartbeat and breathing • Brain Death:Irreversible loss of functioning in the

entire brain, both the cortex and brainstem.

Problems with Cardiopulmonary criteria for death

Before the development of intensive care, patients were declared dead when breathing and circulation stopped.

After cessation of heartbeat and breathing, brain function ceases within minutes unless artificial life support is instituted.

With the development of the ICU, circulation and breathing can be sustained for months after the brain has irreversibly ceased to function.

Some defendants in murder trials have contended that the victims death was caused by removal of vital organs, not their actions.

LEGALLY ACCEPTED CRITERIA FOR BRAIN DEATH

Brain death is a loss of brainstem reflexes such as:

Pupillary light reflexCorneal reflexesDoll’s eyes (oculocephalic) reflexesCaloric responses to iced water

stimulation of the tympanic membraneAbsence of spontaneous respirationIt is an irreversible loss of functioning in

the entire brain, both cortex and brainstem.

• Brain death should only be determined to be present if you have excluded other causes of markedly decreased brainstem and respiratory function.

• You must be certain that the patient is not suffering from

• A. an overdose of barbiturates• B. is hypothermic• C. is hypotensive• D. or the use of neuromuscular blocking

agents• They can all stimulate brain death.

Brain death does not specifically require determination by a neurologist if the physician managing the patient is comfortable with the criteria described and how to verify them.

If a patient is brain dead, then they are dead. The physician does not need a court order or a relative’s permission to remove life support.

USMLE would want you to “discuss with the family”, “explain your findings” or “build consensus” and explain what brain death means to the patient’s family rather than just turning off the ventilator.

Harvesting organs from a person that is brain dead

You can harvest organs from a brain-dead person if the family consents.

You do not have to wait for the person’s heart to stop.

It is better to remove the organ while the heart is still beating.