RPFT Exam Question No 24:

Question No 24:

A patient will undergo bronchial provocation testing with methacholine chloride
(Provocholine). Baseline spirometry reveals the FVC is 4.00 L and FEV1is 3.00 L. The
provocative dose 20% (PD20) can be calculated when which of the following
measurements occur?

A. The FVC falls below 3.20 L, or the FEV1falls below 2.40 L.
B. The FEV, falls below 2.40 L, regardless of change in FVC.
C. The FVC falls below 3.20 L and the FEV1falls below 2.40 L.
D. The ratio FEV1/FVC falls below 0.8.

Answer: B