Patients in a 'vegetative state' have suffered severe brain damage and have lost the ability to respond to external stimulation, a neurologist explained.
Physician Chin Kim-fai said such patients could breathe by themselves and have a normal heartbeat, but they cannot respond to the outside world. 'Patients may be able to hear sounds, but they do not know its source and cannot recognise anyone. Most have to be fed by tubes.'
Brain cells cannot recover once they are damaged. Such harm can be caused by accidents or diseases such as stroke, cardiac arrest or encephalitis. The cells start to die if starved of oxygen for between three and five minutes, Dr Chin said. When a person's brain stem is determined to be dead, the person is certified dead. But vegetative state is not recognised as death in any of the world's legal systems.
