Which of the following are necessary to ensure a valid single-breath diffusing capacity of the lungs (DLCO) test result?
I. Two or more acceptable tests should be averaged.
II. Breath-hold time should be between 3 and 5 seconds.
III. Corrections for hemoglobin (Hb) and COHb should be included.
IV. The maneuvers should be reproducible to within 10%.

Question

Which of the following are necessary to ensure a valid single-breath diffusing capacity of the lungs (DLCO) test result?
I.	Two or more acceptable tests should be averaged.
II.	Breath-hold time should be between 3 and 5 seconds.
III.	Corrections for hemoglobin (Hb) and COHb should be included.
IV.	The maneuvers should be reproducible to within 10%.

Quizplus · Accepted Answer

I is necessary to ensure the accuracy of the test result through averaging. II is necessary because it ensures that gas exchange between the alveoli and pulmonary capillaries is complete. III is necessary because it corrects for hemoglobin concentration in the blood, which affects oxygen diffusion. IV is necessary to ensure that the test results are consistent and reproducible over time. Therefore, choices I, III, and IV are necessary for a valid single-breath diffusing capacity of the lungs (DLCO) test result.

Which of the Following Are Necessary to Ensure a Valid