Narcolepsy is a disturbance of the sleep-wake cycle. The condition is
characterized by irresistible sleep attacks, cataplexy, hallucinations
, sleep paralysis, twilight state and nocturnal sleep disorders. For t
he diagnosis, sleep attacks, cataplexy and pathological changes have t
o be revealed by the multiple sleep latency test (MSLT) and in the pol
ysomnographic recording. The aetiology of the disease is unknown. The
association between narcolepsy and HLA-DR2 and HLA-DQw1 in more than 9
0% of the sufferers suggests an autoimmune basis; to date, however, th
is has not yet been proven It is probable that narcolepsy is of signif
icance for anaesthesia, and appears in particular as a result of posto
perative disorders of vigilance. Sleep paralysis or twilight state mus
t be distinguished from metabolic, respiratory, and drug-induced distu
rbances and from a central anticholinergic syndrome. Cholinergic neuro
nes seem to play a particular role in disorders of vigilance. lpl the
presence of postoperative disorders of vigilance, narcolepsy should be
considered in the differential diagnosis.