RPFT RPFT Spirometry Technique & Maneuver Acceptability 2

Question 1

What patient instruction is most important immediately before performing a maximal inspiratory maneuver for MIP (PImax) testing?

Accepted Answer

Exhale completely to residual volume before inhaling maximally

Answer

MIP is measured from residual volume (RV) because lung mechanics at RV provide the greatest mechanical advantage for inspiratory muscles.

Question 2

A slow vital capacity (SVC) is larger than the FVC in a patient with COPD. What does this finding indicate?

Accepted Answer

Air trapping causes dynamic airway collapse during forced exhalation, reducing FVC

Answer

In obstructive disease, forced expiration causes dynamic collapse of airways, trapping air and yielding a lower FVC than the more slowly measured SVC.

Question 3

During a forced vital capacity maneuver, what does a 'notch' or dip on the descending limb of the flow-volume loop suggest?

Accepted Answer

Upper airway obstruction or glottic closure during exhalation

Answer

A mid-expiratory notch typically indicates variable upper airway obstruction, such as vocal cord dysfunction or tracheal lesion causing intermittent flow interruption.

Question 4

Which spirometric index is most sensitive for detecting early small airways disease?

Accepted Answer

FEF25-75% (mid-maximal expiratory flow)

Answer

FEF25-75% reflects flow in the effort-independent portion of exhalation driven by small airway recoil and is the earliest spirometric marker of peripheral airway disease.

Question 5

An FEV1/FVC ratio of 0.65 in a 68-year-old patient is below the predicted value of 0.74. What is the correct interpretation using ATS/ERS criteria?

Accepted Answer

Obstruction is present because the ratio is below the lower limit of normal (LLN)

Answer

ATS/ERS guidelines recommend using the LLN (5th percentile of predicted) rather than a fixed 0.70 cutoff to avoid over-diagnosing obstruction in the elderly.

RPFT - Registered Pulmonary Function Technologist Practice Test

RPFT - Registered Pulmonary Function Technologist Practice Test

RPFT RPFT Spirometry Technique & Maneuver Acceptability 2