11.30: Sleep Apnea

Question 1

What is sleep disordered breathing and 3 types?

Answer 1

1. OSA: due to upper airway obstruction during sleep
2. Central sleep apnea: failure of brain to initiate respiration: CHF of CNS disease
3. Obesity-hypoventilation syndrome: almost all have OSA but hypoventilate even when awake

Question 2

Physiology of OSA?

Answer 2

• Fall asleep and tongue falls backwards against posterior nasopharynx causing apnea
• Chest/abdomen still moving trying to breathe creating negative pressure in trachea sucking tongue back
• Body will wake up with gasp / snore in which you sleep normal for a bit

Question 3

What is apnea?

Answer 3

• 10 second period of complete airflow cessation

Question 4

What is a polysomnogram?

Answer 4

• Test performed on ptn when you suspect OSA

Question 5

Difference on polysomnogram between OSA and central apnea?

Answer 5

• In central apnea there is NO thoracic effort during period of apnea

Question 6

Difference in treating types of apnea?

Answer 6

• All the same
• Give cPAP “Continuous positive airway pressure”
• Tell to lose weight

Question 7

What is hypopnea?

Answer 7

Partial reduction in airflow

Question 8

Metric in polysomnogram?

Answer 8

AHI: “Apnea-hypopnea index”

• Combined 10 second periods of the two
• 0 - 5 is normal

Question 9

Risk factors or OSA?

Answer 9

1. Obesity
2. Large neck > 17in
3. Htn
4. Older males
5. High mallampati classification

Question 10

What is mallampati classification?

Answer 10

• 1 to 4 scale of space between uvula and tongue

- Higher the scale, less the space

Question 11

Risk factors of central sleep apnea?

Answer 11

1. CHF

2. Central nervous disease

Question 12

Consequences of sleep apnea?

Answer 12

1. Terribly poor sleep from brain activation
   a. Daytime hypersomnolence
   b. Intellectual impairment
2. Repeated episodes of hypoxia
   a. Leads to pulm htn. from pulm vasoconstriction
   b. Polycythemia

Question 13

What is hypersomnolence?

Answer 13

• Falling asleep when you shouldn’t

- EG, fall asleep talking to someone

Question 14

Impact of OSA treatment on CHF?

Answer 14

• Decreases risk

Question 15

Sleep apnea weight loss?

Answer 15

1. Weight loss
2. AVOID sedatives
3. Treat nasal congestion
4. Avoid sleeping on back
5. CPAP, BiPAP

Question 16

How is paroxysmal nocturnal dyspnea different from OSA?

Answer 16

• These patients are actually waking up in the middle of the night short of breath

Question 17

What is leading cause of cancer death in men and women?

Answer 17

Lung cancer

Question 18

Screening rationale for catching lung cancer?

Answer 18

• Good to catch it early to increase survival synce stage I is asymptomatic
• However, Lung cancer will be around for long time before detectable on imaging with high chance of metastasizing during this time
• Screening has shown no impact on lung cancer mortality: just knew you had it for longer period of time

Question 19

What is lead time bias?

Answer 19

• Screening for cancer makes it appear as ptns. survive for longer periods of time
• In reality you are just discovering it earlier since it takes long time for ptn. to present with symptoms

Question 20

What is growth time bias?

Answer 20

• Screening is catching the slow growing cancers making it look like survival is longer
• In the control group without screening you are just detecting the fast growing tumors that present which in fact are the most deadly
• *It is not the screening that is increasing survival it is the rates of growth of the two different tumors you are detecting

Question 21

What does USPSTF recommend?

Answer 21

NOT to screen for lung cancer!!!

Question 22

Is calcified lesion worrisome in lungs?

Answer 22

• NO!
• We are worried about non calcified lesions in lung
• Is considered worrisome in breast

Question 23

What is LDCT?

Answer 23

• Low dose cat scan w/o contrast

Question 24

What does USPSTF recommend?

Answer 24

• Annual LDCT for ptn 55-80 w/ 30 pack year history smoking and have not quit in last 15 years