Sleep Disordered Breathing

Question 1

NREM

Answer 1

Non-rapid eye movement sleep

Dependence on metabolic control

Loss ov voluntary control

Permissive of resp periodicity

Alveolar hypoventilation

Increased UA resistance

Question 2

REM sleep

Answer 2

Rapid eye movement sleep

Decreased/absent metabolic response

Inhibition/paralysis of postural muscles including UA and accessory breathing muscles

Irregular, shallow respiration/apnea

May result in severe hypoventilation/hypoxemia

Question 3

What are the 3 major categories of sleep related breathing disorders?

Answer 3

Central sleep apnea syndromes

Obstructive sleep apnea syndromes

Sleep related hypoventilation/hypoxemic syndromes (including COPD, central hypoventilation, obseity hypoventilation, neuromuscular/chest wall disorders)

Question 4

What can cause central sleep apnea syndromes?

Answer 4

Primary central sleep apnea (can be of infancy)

Cheyne-Stokes breathing

High altitude periodic breathing

Medical conditions (not CSB)

Drug or substance

Question 5

What are the obstructive sleep apnea syndromes?

Answer 5

Adult obstructive sleep apnea

Pediatric obstructive sleep apnea syndrome

Question 6

What are the sleep related hypoventilation/hypoxemia syndromes?

Answer 6

• *Alveolar hypoventilation syndromes**
• Non-obstructive alveolar hypoventilation, idiopathic
• Congenital central alveolar hypoventilation syndrome
• *Sleep related hypoventilation/hypoxemia due to:**
• medical condition
• pulm parenchymal or vascular pathology
• lower airway obstruction
• neuromuscular/chest wall disorders

Question 7

Apnea v. hypopnea

Answer 7

Apnea = cessation of airlow for >10 seconds

Hypopnea = reduction in airflow & respiratory effort

Question 8

What are the 3 types of apneas you can get?

Answer 8

Obstructive: apnea with ventilatory effort; associated with upper airway obstruction

Central: apnea without ventilatory effort

Mixed: begins with central apnea, ends as obstructive apnea

Question 9

Acute consequences of obstructive apneas

Answer 9

Abrupt arousal from sleep

O2 desat

Systemic BP swings

Decreased CO

Increased RV and LV afterload

Increased pulmonary arterial pressure

Increased MVO2, decreased coronary blood flow

Increased arterial stiffness

Vagal increase; sympathetic surges

Question 10

What are the clinical manifestations of obstructive sleep apnea?

Answer 10

Snoring, with periods of silence

Daytime sleepiness

Poor sleep quality/insomnia

Awaking wtih sensation of choking

Morning HA/dry mouth/poor memory/conc

Question 11

What are the cardio/cerebrovascular associations with OSA?

Answer 11

Systemic htn

Decreased LV function

First stroke & recurrent stroke

If OSA, sudden death occurs nocturnally

If OSA, incident stroke occurs in sleep 48% of time

Increased risk for all cause and coronary related mortality

Question 12

Management of OSAS

Answer 12

weight loss

sleep position- avoid supine

alcohol/sedative avoidance

oral devices

surgery

CPAP

Question 13

What is Cheyne-Stokes breathing wtih central sleep apnea?

Answer 13

Associated with heart failure; if you have CSB & HF, increased mortality risk

Asphyxia

Arousal

Disrupted sympathovagal balance

Acute systemic and pulmonary pressor responses

Increased complex ventricular arrhythmias

Question 14

How do you treat CSB/CSA?

Answer 14

Treat CSF: diuretics, ACEI, beta blockers, transplant

O2 alone: to prevent SaO2 decrease

Positive airway pressure

Question 15

What is central hypoventilation syndrome?

Answer 15

“Ondine’s curse”

Awake hypoxemia & hypoventilation

Congenital or acquired: the below are options

Infarct/reduced respiratory afferent input to dorsal respiratory group of medullary neurons, nucleus tractus solitarius

preBotzinger complex neurons of ventolateral medulla: ALS, multiple systems atrophy, Parkinson’s, aging

Treatment: ventilation 24/7 with tracheostomy

Question 16

Biot’s breathing = Cluster breathing

Answer 16

Irregular breathing: quick, shallow inspirations followed by regular or irregular periods of apnea

Associated with opoids, also brain damage from stroke, trauma, increased ICP

Poor prognosis

Question 17

COPD and sleep

Answer 17

Worse outcomes if you have O2 desat during sleep, even if your awake stat’s are ok

Question 18

What disorders can you associate with NREM sleep?

Answer 18

• *Congenital & acquired sleep apnea & hypoventilation syndromes, drug related abnormal breathing**
• because you lose voluntary control
• *Cheyne-Stokes breathing, obstructive sleep apnea**
• dysfunctino of normal respiratory periodicity &, for OSA, you have increased upper airway resistance during NREM sleep
• *Sleep related hypoventilation/ hypoxemic syndromes including obseity hypoventilation syndrome, COPD, neuromuscular/chest wall disorders, metabolic syndrome**
• Exacerbation of normal hypoventilation because you have hypoventilation during NREM sleep

Question 19

What disorders can you associate with REM sleep?

Answer 19

Central Apneas
- due to decreased metabolic response & irregular, shallow respiration

OSA, hypoventilation syndromes (OHS, COPD, NM weakness)
- secondary to the paralysis during REM sleep

Central alveolar respiration
- secondary to irregular, shallow respiration