Vegetative state
A vegetative state (VS) or post-coma unresponsiveness (PCU)[1] is a disorder of consciousness in which patients with severe brain damage are in a state of partial arousal rather than true awareness. After four weeks in a vegetative state, the patient is classified as being in a persistent vegetative state (PVS). This diagnosis is classified as a permanent vegetative state some months (three in the US and six in the UK) after a non-traumatic brain injury or one year after a traumatic injury. The term unresponsive wakefulness syndrome may be alternatively used,[2] as "vegetative state" has some negative connotations among the public.[3]
Vegetative state
There are three main causes of PVS (persistent vegetative state):
Potential causes of PVS are:[20]
In addition, these authors claim that doctors sometimes use the mnemonic device AEIOU-TIPS to recall portions of the differential diagnosis: Alcohol ingestion and acidosis, epilepsy and encephalopathy, infection, opiates, uremia, trauma, insulin overdose or inflammatory disorders, poisoning and psychogenic causes, and shock.
Epidemiology[edit]
In the United States, it is estimated that there may be between 15,000 and 40,000 patients who are in a persistent vegetative state, but due to poor nursing home records exact figures are hard to determine.[39]
History[edit]
The syndrome was first described in 1940 by Ernst Kretschmer who called it apallic syndrome.[40] The term persistent vegetative state was coined in 1972 by Scottish spinal surgeon Bryan Jennett and American neurologist Fred Plum to describe a syndrome that seemed to have been made possible by medicine's increased capacities to keep patients' bodies alive.[9][41]
Society and culture[edit]
Ethics and policy[edit]
An ongoing debate exists as to how much care, if any, patients in a persistent vegetative state should receive in health systems plagued by limited resources. In a case before the New Jersey Superior Court, Betancourt v. Trinitas Hospital, a community hospital sought a ruling that dialysis and CPR for such a patient constitutes futile care. An American bioethicist, Jacob M. Appel, argued that any money spent treating PVS patients would be better spent on other patients with a higher likelihood of recovery.[42]
The patient died naturally prior to a decision in the case, resulting in the court finding the issue moot.
In 2010, British and Belgian researchers reported in an article in the New England Journal of Medicine that some patients in persistent vegetative states actually had enough consciousness to "answer" yes or no questions on fMRI scans.[33] However, it is unclear whether the fact that portions of the patients' brains light up on fMRI will help these patient assume their own medical decision making.[33] Professor Geraint Rees, Director of the Institute of Cognitive Neuroscience at University College London, responded to the study by observing that, "As a clinician, it would be important to satisfy oneself that the individual that you are communicating with is competent to make those decisions. At the moment it is premature to conclude that the individual able to answer 5 out of 6 yes/no questions is fully conscious like you or I."[33] In contrast, Jacob M. Appel of the Mount Sinai Hospital told the Telegraph that this development could be a welcome step toward clarifying the wishes of such patients. Appel stated: "I see no reason why, if we are truly convinced such patients are communicating, society should not honour their wishes. In fact, as a physician, I think a compelling case can be made that doctors have an ethical obligation to assist such patients by removing treatment. I suspect that, if such individuals are indeed trapped in their bodies, they may be living in great torment and will request to have their care terminated or even active euthanasia."[33]