Sleep Medicine & Neuromuscular Disorder

Question 1

What is the most powerful zeitgeber entraining the sleep–wake rhythm?

Answer 1

Light

Question 2

What structure in the brain acts as the master circadian rhythm generator in mammals, and where is it located?

Answer 2

Suprachiasmatic nucleus; anterior hypothalamus

Question 3

Stimulants such as amphetamines and modafinil promote wakefulness by…?

Answer 3

increasing excitatory neurotransmitters (norepinephrine, dopamine, and hypocretin).

Question 4

Caffeine increases wakefulness by..?

Answer 4

blocking the receptors of adenosine, a CNS neurotransmitter.

Question 5

Which neurotransmitter is responsible for rapid eye movement sleep generation?

Answer 5

Acetylcholine

Question 6

When is melatonin secreted? What is its function?

Answer 6

Secreted at night; promotes sleep by causing drowsiness and lowering body temperature (think of melatonin as the darkness signal.)

Question 7

A 19-year-old woman sleeps from 3 am until 11 am daily. She starts college in 1 month and has 7 am classes. What circadian rhythm sleep disorder does she have? When would you give her melatonin?

Answer 7

She has a delayed sleep phase disorder; should receive melatonin early in the night to help her fall asleep earlier.

Question 8

A 76-year-old man sleeps from 7 pm until 4 am once a day. He wants to join his local Bingo group that meets at 8 pm, and he would like to stay up longer at night. What circadian rhythm sleep disorder does he have, and when would you give him melatonin to treat it?

Answer 8

He has advanced sleep phase disorder, and he should receive melatonin in the early morning, after being cautioned that melatonin can cause drowsiness

Question 9

Ghrelin stimulates appetite, and leptin inhibits appetite.
Ghrelin = Grow
Leptin = Lean

Question 10

What is/are the effect(s) of REM sleep compared to NREM sleep on the autonomic nervous system?

Answer 10

A transient increase in sympathetic activity during phasic REM sleep

Question 11

How are hormones ghrelin and leptin affected by sleep deprivation?

Answer 11

Ghrelin increases, and leptin decreases

Question 12

What characteristic EEG waveforms define sleep stage N2?

Answer 12

K-complex and sleep spindles

Question 13

What are two defining characteristics of narcolepsy on PSG with MSLT?

Answer 13

Decreased SOL and ≥ two SOREMPs on MSLT

Question 14

Sleep apnea is uncommon as the sole etiology for significant pulmonary hypertension; when present, other etiologies should be considered.

Question 15

Increased risk for cardiovascular disease in the context of OSA is tied more to degree of oxygen desaturation than to AHI.

Question 16

Which patients should not undergo a portable home sleep study?

Answer 16

Patients with cardiovascular disease, stroke, COPD, and hypoventilation syndromes

Question 17

What is the best historic predictor of OSA?

Answer 17

Witnessed apneas— daytime sleepiness is the most common symptom

Question 18

What is the #1 reason for residual daytime sleepiness in patients who are on CPAP therapy for SDB?

Answer 18

CPAP noncompliance

Question 19

Nocturia associated with OSA improves with CPAP use.

Question 20

Which outcome is the most likely to improve with use of CPAP in OSA?

Answer 20

Daytime sleepiness

Question 21

A 74-year-old man with heart failure (LVEF 20%) and atrial fibrillation is referred for frequent nocturnal desaturations noted during a recent hospitalization. What type of SDB would you be concerned about?

Answer 21

Cheyne-Stokes respiration

Question 22

Would a patient with Cheyne-Stokes respiration be hypercapnic, hypocapnic, or eucapnic on a daytime arterial blood gas?

Answer 22

Typically hypocapnic

Question 23

What is the first step in the management of CSRs in the setting of heart failure?

Answer 23

Optimize heart failure (i.e., ACE inhibitors)

Question 24

What is the most important determinant of sleep- related hypoxemia in COPD?

Answer 24

Hypoventilation

Question 25

The hallmark of narcolepsy is daytime sleepiness. If a patient is not sleepy, the diagnosis of narcolepsy is highly unlikely.

Question 26

Mnemonic
Sleep hallucinations—GO to sleep. POp awake.
HypnaGOgic HypnoPOmpic

Question 27

Mnemonic
Clinical features of narcolepsy—Some Patients Can Fall Hard

Sleepiness
Paralysis
Cataplexy Fragmentation of sleep Hallucinations

Question 28

An MSLT is suggestive of narcolepsy if the mean sleep latency is < 8 minutes and if there are at least two SOREMPs.

Question 29

What clinical feature is virtually pathognomonic for narcolepsy?

Answer 29

Cataplexy

Question 30

Clinical features of RLS—
URGE

Urge to move legs Rest precipitates
symptoms
Getting up and moving
alleviates symptoms Evening and nighttime
worsening of symptoms

Question 31

What is the treatment of choice for Idiopathic Hypersomnia?

Answer 31

Orexin (hypocretin)

Question 32

Decreased levels of which neurotransmitter is implicated in narcolepsy?

Answer 32

Modafinil or armodafinil

Question 33

Although RLS and periodic limb movement disorder are similar, they are two different conditions. RLS is a clinical diagnosis and does not require a PSG. However, if a PSG is performed, PLMs usually are found.

Question 34

RLS is related to low CNS iron stores, which disrupt dopamine synthesis. Dopamine agonists relieve RLS.

Question 35

Parasomnias typically occur during NREM sleep and thus are more often present during the first half of the night.

Question 36

Patients with RBD are at high risk of developing which condition?

Answer 36

Parkinson disease

Question 37

What inhibits melatonin production?

Answer 37

Light

Question 38

A 32-year-old woman reports sleeping only 3 hours per night for many years. She reports good sleep quality, denying any daytime impairment, sleepiness, or distress. Does this patient have insomnia?

Answer 38

No because the patient is not experiencing impairment or distress as a result of the short sleep duration.

Question 39

The gold standard treatment of insomnia of long duration is CBT.

Question 40

Nocturnal NIPPV is the cornerstone of respiratory management in patients with neuromuscular disorders.

Question 41

Features that distinguish GBS from other neuromuscular disorders include neuropathic pain, autonomic dysfunction, and diminished deep tendon reflexes on physical exam.

Question 42

What are the only disease- modifying treatment options for GBS?

Answer 42

Plasmapheresis or IVIG

Question 43

Signs of upper and lower motor neuron involvement are very characteristic of ALS. Spasticity, atrophy, and fasciculations will help distinguish ALS from other neuromuscular disorders.

Question 44

Classically, the muscle weakness of myasthenia gravis worsens as the day progresses.

Question 45

Lambert–Eaton syndrome is strongly associated with small cell lung cancer.

Answer 45

In contrast to myasthenia gravis, repetitive nerve stimulation results in increased amplitude of action potentials at Lambert Eaton

Question 46

Symptoms of organophosphate poisoning?

Answer 46

Mnemonic
SLUDGE—
Salivation Lacrimation Urination Defecation GI upset Emesis

Question 47

PFT findings in severe kyphoscoliosis are?

Answer 47

low TLC and VC, with preserved RV.
This results in an increased RV:TLC ratio.