12-17-2007, 08:26 AM
A 54-year-old male presents to your clinic complaining of dyspnea on exertion. The patient notes that he
previously was quite active despite having had poliomyelitis at age 14. He was left with no chronic motor
impairments, although he remembers being confined to an "iron lung" for 6 months. One year ago the
patient played tennis three time weekly and jogged 3 miles a day; now he cannot jog a mile. He also
notes that he is unable to sleep flat at night because of dyspnea. On physical examination, the patient
appears well developed and has no obvious difficulty with speech. When the patient lies flat, paradoxical
abdominal motion is seen. On chest examination there are no crackles, wheezes, or rhonchi. However,
usual thoracic expansion with inspiration is not seen and diaphragmatic excursion is not appreciated.
Which of the following statements about the patient's condition is true?
A. An elevation in the alveolar-arterial (A-a) gradient is expected.
B. The patient's baseline PaCO2 while awake is invariably elevated.
C. A cuirass is a form of positive-pressure ventilation that may be used to assist the patient with
nocturnal ventilation.
D. The patient's maximal voluntary ventilation is normal.
E. The presence of respiratory muscle dysfunction during the original presentation of polio increases the
likelihood that the patient will develop chronic respiratory difficulties with postpolio syndrome
previously was quite active despite having had poliomyelitis at age 14. He was left with no chronic motor
impairments, although he remembers being confined to an "iron lung" for 6 months. One year ago the
patient played tennis three time weekly and jogged 3 miles a day; now he cannot jog a mile. He also
notes that he is unable to sleep flat at night because of dyspnea. On physical examination, the patient
appears well developed and has no obvious difficulty with speech. When the patient lies flat, paradoxical
abdominal motion is seen. On chest examination there are no crackles, wheezes, or rhonchi. However,
usual thoracic expansion with inspiration is not seen and diaphragmatic excursion is not appreciated.
Which of the following statements about the patient's condition is true?
A. An elevation in the alveolar-arterial (A-a) gradient is expected.
B. The patient's baseline PaCO2 while awake is invariably elevated.
C. A cuirass is a form of positive-pressure ventilation that may be used to assist the patient with
nocturnal ventilation.
D. The patient's maximal voluntary ventilation is normal.
E. The presence of respiratory muscle dysfunction during the original presentation of polio increases the
likelihood that the patient will develop chronic respiratory difficulties with postpolio syndrome