The wide spectrum of consciousness disorders

Medically speaking, the term consciousness is the state of the patient’s awareness of self and environment and his responsiveness to external stimulation and inner need. Temporary loss of consciousness may be caused by impaired cerebral perfusion (syncope, fainting), cerebral ischemia, migraine, epileptic seizures, metabolic disturbances, sudden increases in intracranial pressure, or sleep disorders. Chronic unconsciousness is a tragic and ironic failure of high-technology treatment to preserve or restore brain function, the primary aim of therapeutics. Management of a patient in a vegetative state or a minimally conscious state requires carefully reaching the correct diagnosis, pronouncing an evidence-based prognosis, and thoughtfully considering the medical, ethical, and legal elements of optimum treatment. This chapter is aimed at exploring the wide spectrum of consciousness disorders, with particular regards to those having a negative impact on quality of life of the patients and their care-givers, including epilepsy, parasomnias, coma and vegetative state.