studies (Figs 1234) were obtained from a 60-year-old man with recurrent
pneumonias for the past 15 years. He has chronic
foul-smelling sputum, increasing shortness of breath, and increasing supplemental
He reports a 50–pack-year history of tobacco use,
but has not smoked for 12 years.
In addition to bilateral crackles and rhonchi posteriorly, he exhibits digital clubbing. His FEV1
is 1.52 L (48% of predicted); FVC, 2.4 L (61% of predicted); and
FEV1/FVC, 0.62. While he is receiving 5 L of oxygen by
nasal cannula, his arterial blood gas analysis reveals a
Po2 of 60 mm Hg, Pco2
of 41 mm Hg, and pH of 7.43. Sputum culture grows Pseudomonas species.
Which one of the following statements concerning this case is not true?