Disorders of Ventilation

Question 1

Four factors that influence ventilation

Answer 1

Arterial Pco2, Arterial pH, Arterial Po2, Brainstem tissue pH

Question 2

What is primary alveolar hypoventilation (Ondine’s Curse)?

Answer 2

Inadequate alveolar ventilation with normal neurologic function, airways, lungs, chest wall and ventilatory muscles.

Question 3

Physical exam findings of primary alveolar hypoventilation (Ondine’s Curse)

Answer 3

non-obese males in 30s-40s. No dyspnea but positive for cyanosis and pulmonary HTN

Question 4

What are treatment options for primary alveolar hypoventilation (Ondine’s Curse)?

Answer 4

O2, positive pressure ventilation at night. Respiratory stimulants (medroxyprogesterone, acetazolamide, theophylline). Diaphragm pacing

Question 5

T/F Pickwickian Syndrome is a decreased respiratory drive and increased load on chest secondary to obesity

Answer 5

True

Question 6

Of the following, which are treatment options for Pickwickian Syndrome: weight gain, Bipap/CPAP, and respiratory stimulants (theophylline, acetazolmide)?

Answer 6

All are treatments except weight gain. Weight loss will actually help an individual with Pickwickian

Question 7

T/F. Prevalence of sleep apnea in Asia is similar to the US despite lower rates of obesity

Answer 7

True

Question 8

What occurs as a result of recurrent collapse of the pharyngeal airway observed with sleep apnea?

Answer 8

Cessation of airflow, Disturbances in gas exchange, Poor sleep quality (reduced REM sleep)

Question 9

What anatomical features are associated with the presence of obstructive sleep apnea?

Answer 9

Neck circumference > 43 cm (17 in) in men and 37 cm (15 in) in women. Narrowing of the lateral airway walls in men. Enlarged (ie, “kissing”) tonsils (3+ to 4+)

Question 10

How is excessive daytime somnolence that occurs with sleep apnea assessed using the Epworth Sleepiness Scale (ESS)?

Answer 10

determine how frequently the patient is likely to doze off in 8 frequently encountered situations. the ESS score should decrease with effective treatment

Question 11

What diagnostic tests are done for sleep apnea?

Answer 11

TSH, RBC, Polysomnography, Home overnight oximetry

Question 12

Define hypopnea

Answer 12

Decreased airflow with a drop in O2 saturation of at least 4%

Question 13

Define apnea

Answer 13

Breath cessation for at least 10 seconds with decrease in O2 saturation

Question 14

What are the values of the respiratory disturbance index (RDI) for each stage of sleep apnea?

Answer 14

Mild sleep apnea: 5-14/hr. Moderate sleep apnea: 15-29/hr. Severe sleep apnea: ≥ 30/hr

Question 15

What is the main treatment of sleep apnea?

Answer 15

CPAP

Question 16

What is the difference between a BiPAP and a CPAP?

Answer 16

CPAP is a continuous positive airway pressure whereas as a BiPAP has lower pressure for exhalation and higher pressure for inhalation

Question 17

What are indications for a BiPAP?

Answer 17

mixed (obstructive and central) sleep apnea and also for impending respiratory failure

Question 18

What is central sleep apnea?

Answer 18

Brain forgets to tell the body to breathe. Seen in premature infants, mixed obstructive sleep apnea, post stroke/traumatic brain injury/CHF