Disorders of Ventilation

Question 1

Treatment of primary alveolar hypoventilation

Answer 1

Supplemental oxygen
Positive pressure ventilation
Respiratory stimulants: Medroxyprogesterone, Acetazolamide, Theophylline
Diaphragm pacing with phrenic nerve stimulation

Question 2

Pickwickian Syndrome

Answer 2

Blunted ventilatory drive and increased mechanical load imposed upon the chest by obesity
Voluntary hyperventilation returns the Pco2 and Po2 toward normal values
Most likely also have obstructive sleep apnea.

Question 3

Pickwickian Syndrome Tx.

Answer 3

Weight loss
NPPV (noninvasive positive pressure ventilation) (Bipap, CPAP)
Respiratory stimulants (not the primary treatment):
Theophylline
Acetazolmide

Question 4

The following features have been associated with the presence of OSAHS

Answer 4

Neck circumference: greater than 43 cm (17 in) in men and 37 cm (15 in) in women.
Narrowing of the lateral airway walls, which is an independent predictor of the presence of OSAHS in men but not women
Enlarged (ie, “kissing”) tonsils (3+ to 4+)

Question 5

Apnea

Answer 5

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

Question 6

Hypopnea

Answer 6

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

Question 7

Apnea-hypopnea index (AHI)

Answer 7

The number of combined events per hour

Question 8

Respiratory disturbance index (RDI)

Answer 8

The number of apneas, hypopneas and respiratory effort related arousals per hour of sleep
Mild sleep apnea: 5-14/hr
Moderate sleep apnea: 15-39/hr
Severe sleep apnea: ≥ 30/hr