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THE VEGETATIVE STATE: PRACTICAL GUIDELINES, MEDICAL DECISION MAKING, AND ETHICAL DILEMMAS
James L. Bernat, MD Dartmouth-Hitchcock Medical Center Lebanon, NH The vegetative state (VS), a disorder of consciousness characterized by wakefulness without awareness, is a tragic and ironic artifact of modern medical technology. Patients reach VS after suffering a pathological process that has producedwidespread damage to cerebral cortical neurons, thalamic neurons, or the white matter connections between the cortex and thalamus, but that largely spares brain stem and hypothalamic neurons. Common etiologies of acute VS are traumatic brain injury, stroke, and neuronal hypoxia and ischemia suffered during cardiopulmonary arrest.1 VS may be a transient stage in recovery from a diffuse brain insultor a chronic, stable condition that has been called the persistent vegetative state (PVS). The ethical issues in managing the VS patient arise from the meaninglessness of a chronically noncognitive existence and the desire of families and other surrogates to make medical decisions about continued life support that respect the patient and are in accord with those the patient would have made.2History In 1972, Bryan Jennett and Fred Plum coined the name persistent vegetative state and defined its essential clinical features.3 Jennett and Plum observed that many patients rendered comatose from head trauma and other brain injuries progressed from a typical eyes-closed comatose state after several weeks to an eyesopen unresponsive and unaware state. Although their sleep-wake cycles returned,these patients appeared to be entirely unaware of themselves and their environment, despite their wakefulness. To the fullest extent determinable, PVS patients appeared incapable of thinking, remembering, feeling, or experiencing. With adequate medical and nursing care, they could remain in this state for many months or years. The diagnosis and prognosis of PVS have reached public attention throughseveral landmark high court rulings involving surrogate’s refusal of life-sustaining treatment, notably the cases of Karen Ann Quinlan in the 1970s, Nancy Beth Cruzan in 1990,4 and the recent highly publicized case of Terri Schiavo.5 To address medical questions about the PVS patient, the Multi-Society Task Force on PVS was impaneled in 1991, comprised of representatives from the American Academyof Neurology, the American Neurological Association, the American Association of Neurological Surgeons, the American Academy of Pediatrics, and the Child Neurology Society. Their report in a two-part article in the New England Journal of Medicine in 1994 contained the most authoritative medical facts on PVS up to that time.6 The American Academy of Neurology drafted a practice parameter on PVSbased on this document.7 In 1996, the British Medical Association published guidelines on diagnostic criteria for PVS that were similar to those of the Task Force.8 The Royal College of Physicians published their revised guidelines on PVS in 2003.9 The subjects of VS and PVS have been reviewed recently in journal articles1,10-13 a book chapter,2 and in a book.14 Definition and Criteria TheMulti-Society Task Force on PVS operationally defined the vegetative state as "a condition of complete unawareness of the self and the environment accompanied by sleep-wake cycles with either complete or partial preservation of brain stem and hypothalamic autonomic, functions." A vegetative state may be a transient stage in the spontaneous recovery from a diffuse brain insult or may be a chronic condition.The Task Force defined the persistent vegetative state as a vegetative state lasting longer than a month.6 Some authorities have coined an additional term permanent vegetative state to refer to a PVS that will not improve. Because this condition also has been abbreviated PVS it has led to confusion. Today, most writers believe it is preferable to simply use the term vegetative state (VS) without...