Toward the end of a nitrogen washout test for functional residual capacity, the expired concentration of N₂ begins rising. What does this probably indicate? A) The patient is trying too hard. B) There is a leak in the system. C) The test is nearing completion. D) N₂ is being trapped in the lungs.

Question

Quizplus · Accepted Answer

The test must occur in a leak proof circuit because the presence of any air increases the measured nitrogen percentages and results in grossly elevated measurements of lung volume.

Toward the End of a Nitrogen Washout Test for Functional