persistent vegetative state

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 1^st month–if at all, recovery is rare beyond the 3^rd 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