persistent vegetative state

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Related to Vegetative states: Persistent vegetative state

state

 [stāt]
condition or situation.
alpha state the state of relaxation and peaceful awakefulness associated with prominent alpha brain wave activity.
anxiety state the condition of experiencing undue anxiety, as in anxiety disorders.
excited state the condition of a nucleus, atom, or molecule produced by the addition of energy to the system as the result of absorption of photons or of inelastic collisions with other particles or systems.
ground state the condition of lowest energy of a nucleus, atom, or molecule.
persistent vegetative state a condition of profound nonresponsiveness in the wakeful state caused by brain damage at whatever level and characterized by a nonfunctioning cerebral cortex, the absence of any discernible adaptive response to the external environment, akinesia, mutism, and inability to signal; the electroencephalogram may be isoelectric or show abnormal activity. Vegetative states raise ethical questions regarding appropriate care, use of resources, and allowing a patient to die.
refractory state a condition of subnormal excitability of muscle and nerve following excitation.
resting state the physiologic condition achieved by complete bed rest for at least 1 hour.
steady state dynamic equilibrium.

persistent vegetative state (PVS),

vegetative state (q.v.) of prolonged duration (defined in different sources as duration of longer than 1 month, 1 year, or 2 years); usually permanent.
See also: vegetative.

persistent vegetative state

a state of wakefulness accompanied by an apparent complete lack of cognitive function, experienced by some patients in an irreversible coma. Vegetative functions and brainstem reflexes are intact, but the cortex is permanently damaged.

persistent vegetative state

Choice in dying A condition caused by injury, disease or illness in which a Pt has suffered a loss of consciousness, with no behavioral evidence of awareness of self or surroundings in a learned manner, other than reflex activity of muscles and nerves for low level conditioned response, and from which to a reasonable degree of medical probability, there can be no recovery; PVS is characterized by a prolonged loss of upper cortical function that may follow acute–eg, infections, toxins, trauma, or vascular events, or chronic–eg, degenerative events; in PVS, Pt is bed-ridden, nutritional support is completely passive, either parenteral or by NG tube; PVS Pts do not require respiratory support or circulatory assistance for survival and are in a state of chronic wakefulness which may be accompanied by spontaneous eye opening, grunts or screams, brief smiles, sporadic movement of facial muscles and limbs; while the eyes blink upon stimulation, they do not do so in response to visual threats; some Pts chew or clamp their teeth; urinary and fecal incontinence is universal; recovery occurs within the 1st month–if at all, recovery is rare beyond the 3rd month. See Advanced directives, DNR, Harvard criteria, Living will, Quinlan. Cf Procurement.
Persistent vegetative state–criteria
1.  No evidence of awareness of environment; inability to interact with others
.
2.  No evidence of sustained, reproducible, purposeful, or voluntary behavioral responses to visual, tactile, auditory, or noxious stimuli
.
3.  No evidence of language comprehension or expression
.
4.  Intermittent wakefulness manifested by the presence of sleep-wake cycles
.
5.  Sufficiently preserved hypothalamic and brain-stem autonomic functions to permit survival with medical and nursing care
.
6.  Bowel and bladder incontinence
.
7. Variably preserved cranial nerve reflexes (pupillary, oculocephalic, corneal, vestibulo-ocular, gag) and spinal reflexes
.

per·sis·tent ve·ge·ta·tive state

(PVS) (pĕr-sis'tĕnt vej'ĕ-tā-tiv stāt)
Vegetative state of prolonged duration (defined in different sources as duration of longer than 1 month, 1 year, or 2 years); usually permanent.
See also: vegetative

persistent vegetative state

A condition caused by diffuse lesions of the thalami, the cortical neurons or of the white matter tracts that connect them. The disorder has proved difficult to define because of uncertainties as to the real meaning of ‘consciousness’, ‘awareness’ and ‘wakefulness’. Patients in a persistent vegetative state can breathe without mechanical assistance. Heart, kidney and intestinal functions are normal and the bladder and bowels empty automatically. At times they appear to be awake. They will respond to painful stimuli by opening their eyes, moving their limbs, breathing more quickly, and occasionally grimacing. The type and degree of brain damage indicates, however, that they cannot perform any of the higher neurological or mental functions known to be essential for any mental processes or appreciation of their situation.

per·sis·tent ve·ge·ta·tive state

(pĕr-sis'tĕnt vej'ĕ-tā-tiv stāt)
Condition of a patient of prolonged duration (defined in different sources as duration of longer than 1 month, 1 year, or 2 years); usually permanent.
References in periodicals archive ?
Adrian Owen, a researcher at the University of Western Ontario who focuses on studying the neural activity of vegetative state patients using a type of brain scanning called functional magnetic resonance imaging (fMRI).
Owen then asked Scott a question he had been hoping to ask a vegetative state patient for a long time: "Are you in any pain?
Researchers at the Medical Research Council Cognition and Brain Sciences Unit and the University of Cambridge have found a patient in a vegetative state who could focus on words as well as a healthy individual.
These strong connections, along with evidence from vegetative state patients, make the thalamus a prime suspect in the hunt for the seat of consciousness.
Ms Englaro has been in a vegetative state since a car accident in 1992, when she was 20.
Colby is a lawyer who has worked with right to die issues primarily as they relate to the persistent vegetative state, the condition wherein a person's body is kept alive long after consciousness is gone.
Some people are concerned that patients with living wills who have requested no extraordinary life-prolonging medical treatments in the case of a vegetative state might not have their intentions respected.
Wood RL: Critical analysis of the concept of sensory stimulation for patients in vegetative states.
Some 10,000 to 25,000 adults and 6,000 to 10,000 children in the United States are diagnosed each year as being in persistent vegetative states.
For caregivers of patients whose vegetative states were deemed permanent, this research may offer hope and a way to reconnect with loved ones.
Panorama will examine how efforts are being made to help patients in vegetative states to communicate with the outside world.
Consequently," it states, "we typically overtreat the dying, we promiscuously employ expensive tests and treatments with low marginal utility, and we allocate few health care resources to preventive health care while we maintain thousands of persons for long periods of time in persistent vegetative states.