What appears to be the role of NPPV for the long-term support of patients with severe stable COPD? ...

(Answer to Q. 1)  ANS: B (page 372)
Cognitive Level: Recall
A. Incorrect response: See explanation B.
B. Correct response: The long-term application of NPPV among severe stable COPD patients has been somewhat controversial. The substantial differences in baseline characteristics among patients entering these trials may explain the conflicting results. Patients who respond favorably had greater hypercapnia and more nocturnal O2 desaturation despite having less severe airway obstruction than patients responding unfavorably to NPPV. These data support the hypothesis that the subgroup of patients most likely to benefit from NPPV is that with substantial daytime CO2 retention (Paco2 >50 to 55 mm Hg) and nocturnal O2 desaturations.
C. Incorrect response: See explanation B.
D. Incorrect response: See explanation B.

(Answer to Q. 2)  ANS: C

(Answer to Q. 3)  ANS: A (page 372)
Cognitive Level: Recall
A. Correct response: Long-term follow-up studies on several hundred patients using NPPV for 3 to 5 years have demonstrated favorable results among patients with postpolio syndrome, various myopathies, and kyphoscoliosis. Survival among patients with amyotrophic lateral sclerosis (ALS) was less favorable because the ALS (underlying disease) progresses more rapidly than with the other pathologies.
B. Incorrect response: See explanation A.
C. Incorrect response: See explanation A.
D. Incorrect response: See explanation A.

(Answer to Q. 4)  ANS: B (page 369)
Cognitive Level: Recall
A. Incorrect response: See explanation B.
B. Correct response: Hypoxemic respiratory failure is characterized by severe hypoxemia (Pao2/Fio2 <200), respiratory distress, tachypnea (>30 breaths/minute), tachycardia, and a non-COPD cause (e.g., ARDS), acute pneumonia, trauma, and acute pulmonary edema.
C. Incorrect response: See explanation B.
D. Incorrect response: See explanation B.

(Answer to Q. 5)  ANS: A (page 371)
Cognitive Level: Recall
A. Correct response: Selection of appropriate patients for NPPV is critical for optimizing success rates and deriving benefits. The following factors are predictors of success of NPPV used for the treatment of acute respiratory failure:
  Cooperative patient
  Intact neurologic function
  Synchrony with the ventilator
  APACHE II score <29
  pH >7.25
  Intact dentition
  Well-controlled air leaking
  Able to control secretions
  Within first 2 hours of using NPPV
 o Reduced respiratory rate (>30 breaths/min)
 o Reduced accessory muscle use
 o Improved gas exchange (increasing Pao2/Fio2 )
B. Incorrect response: See explanation A.
C. Incorrect response: See explanation A.
D. Incorrect response: See explanation A.

Thank you very much!!!