Lecture 2 Flashcards
Quick overview of patient SM
Male
Sleepy from teens, developed cataplexy at 18
Was diagnosed with narcolepsy when discharged from the army in 1990
Currently takes Zyrem for cataplexy, dexandrine for narcolepsy
What is the nature of narcolepsy?
Literally seized by somnolence
Monsieur G was the first case
What are some of the symptoms of narcolepsy?
REM dysregulation Sleepiness Cataplexy Sleep attacks Sleep paralysis Hallucinations
What is cataplexy?
Jelly episodes
Loss of muscle tone usually starting in the face
Lasts a few seconds
Absent reflexes during episodes
Strong (usually positive) emotions are triggers
What are the four stages of sleep?
Stage 1- drowsy, alpha/theta waves, rolling eyes
Stage 2- light sleep, theta waves, diminished EEG
Stage 3- deep sleep, delta waves, no eye movement, even further diminished EEG
REM- waves look like awake, atonia, and aptly rapid eye movement
Multiple sleep latency test
Given 20 mins to fall asleep five times
Fall asleep in less than five mins= hypersomnia
Fall asleep in more than fifteen mins= Normal
Narcoleptics fall asleep in roughly 2 mins
What is the most important brain area involved in sleepiness?
Ventrolateral preoptic area (VLPO)
It is a sleep area that releases GABA to inhibit wakeful areas
What is the most important brain area involved in wakefulness?
Tuberothamillary nucleus
It is stimulated by hypocretin and works alongside the dorsal raphe and locus correlus
What three things does hypocretin/orexin do?
Promotes wakefulness
Maintains muscle tone when awake
Stabilises the sleep wake switch
Treatments for narcolepsy
Lifestyle changes
Modafinil- wake promoting
Dexamphetamines- last resort wake promoting
Antidepressants- sometimes for cataplexy
Xyrem or sodium oxybate- gold standard for cataplexy and sleep fragmentation treatments