Randy test 2 quizzes

Which lung volume cannot be measured directly by spirometry?

Functional residual capacity

Total lung capacity (TLC) is calculated by combining which measurements?

FRC + IC

Why may helium dilution underestimate lung volumes in obstructive lung disease?

Trapped gas does not communicate with the circuit.

Which gas dilution technique requires the patient to breathe 100% oxygen?

Nitrogen washout

Nitrogen washout testing may be prolonged in patients with:

Severe airflow obstruction.

During body plethysmography, what maneuver does the patient perform against a closed shutter?

Panting at FRC.

Which lung volume is calculated once FRC is known?

Residual volume.

Diffusing capacity primarily reflects the lung’s ability to:

Transfer gas across the alveolar–capillary membrane.

Why is carbon monoxide (CO) used to assess diffusing capacity rather than oxygen?

CO has a much higher affinity for hemoglobin.

An acceptable breath-hold time for the single-breath DLCO maneuver is:

8–12 seconds.

Which of the following would invalidate a DLCO maneuver?

Exhalation time of 6 seconds.

Which condition would most likely result in a decreased DLCO?

Emphysema.

Daily calibration of a flow-measuring device requires syringe injections at:

Three different flow ranges.

Acceptable calibration volume for a 3-L syringe using a flow device is:

2.90–3.10 L.

Poor spirometry technique can result in all EXCEPT:

Improved clinical decision-making.

Spirometry can identify all of the following EXCEPT:

Restrictive lung disease.

Which lung capacity is calculated as ERV + RV?

Functional residual capacity.

Which value represents the amount of air exhaled in the first second of a forced vital capacity maneuver?

FEV₁.

According to ATS/ERS standards, an acceptable adult FVC maneuver must include:

≥6 seconds of exhalation OR a volume-time plateau.

Spirometry testing should be terminated when:

The patient becomes excessively dyspneic or uncooperative.

During daily calibration, a 3-L syringe is discharged into a spirometer. The measured volume is 2.4 L. What should the RT do NEXT?

Recalibrate and remove the device from service if the error persists.

A patient becomes light-headed and markedly dyspneic after six FVC attempts. Acceptable and repeatable criteria have not been met. What is the MOST appropriate action?

Stop testing and document the reason.