PFT Questions and Answers Latest
Update 2024/2025, 100% Verified
Introduction
This document provides a comprehensive set of questions and answers related to Pul-
monary Function Tests (PFTs) for the 2024/2025 academic year. It is designed to assist
students, healthcare professionals, and educators in understanding key concepts, proce-
dures, and interpretations associated with PFTs. The content focuses on essential topics,
eliminating unnecessary jargon, and includes 100 additional relevant questions to enhance
learning.
1 Spirometry Basics
1.1 What is the purpose of performing PFTs?
Answer: PFTs evaluate lung functions, volumes, ventilation, diffusing capacity, and
metabolic aspects to diagnose lung diseases, assess therapy, and quantify disease severity.
1.2 What is the American Thoracic Society standard for volu-
metric accuracy of spirometers?
Answer: ś3% error or within 50 mL of the reference value.[](https://www.stuvia.com/en-
us/doc/5989985/pft-final-exam-with-100-correct-answers-2024)
1.3 Which test is used as an indicator of ventilatory inspiratory
muscle strength?
Answer: Maximal Inspiratory Pressure (MIP).[](https://www.stuvia.com/en-us/doc/7125079/pft-
final-exam-questions-and-answers-latest-update-2025.docx)
1.4 What is the most important measurement for distinguishing
an obstructive impairment?
Answer: FEV1/VC ratio.[](https://www.stuvia.com/en-us/doc/7285347/pft-final-exam-
2025-100-correct-answers)
1.5 What are the indications for spirometry?
Answer: Diagnose lung disease, assess occupational/environmental exposure, evaluate
therapy, monitor disease progression, assess surgical risk, quantify disability, and support
1
,clinical research.[](https://www.stuvia.com/en-us/doc/8262839/pft-final-exam-updated-
actual-exam-questions-and-correct-answers)
1.6 What is the normal range for the FEV1/FVC ratio in healthy
adults?
Answer: Greater than 0.70.[](https://www.ncbi.nlm.nih.gov/books/NBK482339/)
1.7 What does a low FEV1/FVC ratio indicate?
Answer: An obstructive ventilatory defect.[](https://www.aafp.org/pubs/afp/issues/2014/0301/p359.h
1.8 How is spirometry performed?
Answer: The patient takes a maximal inspiration, followed by a forceful exhalation
(blast) and continues to exhale completely.[](https://www.ncbi.nlm.nih.gov/books/NBK482339/)
1.9 What are the three phases of spirometry?
Answer: Maximal inspiration, a blast of exhalation, and complete exhalation to the end
of the test.[](https://www.ncbi.nlm.nih.gov/books/NBK482339/)
1.10 What is the Forced Vital Capacity (FVC)?
Answer: The total volume of air exhaled during a forced maneuver.[](https://www.ncbi.nlm.nih.gov/bo
1.11 What is Forced Expiratory Volume in 1 second (FEV1)?
Answer: The volume of air exhaled in the first second of a forced maneuver.[](https://www.ncbi.nlm.nih
1.12 What is the significance of a slow vital capacity (VC)?
Answer: It measures the total volume of air exhaled slowly, often higher than FVC
in obstructive diseases due to less airway compression.[](https://www.stuvia.com/en-
us/doc/7285347/pft-final-exam-2025-100-correct-answers)
1.13 What is the Wright Respirometer used for in PFTs?
Answer: It measures Slow Vital Capacity.[](https://www.stuvia.com/en-us/doc/7125079/pft-
final-exam-questions-and-answers-latest-update-2025.docx)
1.14 What is the acceptable variability between spirometry tri-
als?
Answer: Results of the two best efforts should be within 0.2 L of each other.[](https://www.aafp.org/pub
2
, 1.15 What indicates a good quality spirometry test?
Answer: A volume-time curve reaching a plateau, expiration lasting at least six seconds,
and flow-volume loops free of artifacts.[](https://www.aafp.org/pubs/afp/issues/2014/0301/p359.html)
2 Lung Volume and Capacity
2.1 What is Respiratory Dead Space?
Answer: Lung volume that is ventilated but not perfused by pulmonary capillary blood
flow, including anatomical and alveolar dead space (physiological dead space).[](https://www.stuvia.com
us/doc/7125079/pft-final-exam-questions-and-answers-latest-update-2025.docx)
2.2 What is the calculation for Alveolar Ventilation?
Answer: (VCO2/PaCO2) Π0.863.[](https://www.stuvia.com/en-us/doc/7125079/pft-
final-exam-questions-and-answers-latest-update-2025.docx)
2.3 What is the normal minute ventilation?
Answer: 510 L/min.[](https://www.stuvia.com/en-us/doc/7125079/pft-final-exam-questions-
and-answers-latest-update-2025.docx)
2.4 What conditions cause a quick increase in dead space?
Answer: Pulmonary emboli, pulmonary hypertension, and conditions causing drastic
shortness of breath.[](https://www.stuvia.com/en-us/doc/7125079/pft-final-exam-questions-
and-answers-latest-update-2025.docx)
2.5 What is the indication for lung volume testing?
Answer: To diagnose restrictive lung disease, assess hyperinflation, differentiate obstruc-
tive vs. restrictive patterns, and standardize other lung function measures.[](https://www.stuvia.com/en
us/doc/8262839/pft-final-exam-updated-actual-exam-questions-and-correct-answers)
2.6 What is Total Lung Capacity (TLC)?
Answer: The total volume of air in the lungs after maximal inspiration.[](https://www.ncbi.nlm.nih.gov
2.7 What is Residual Volume (RV)?
Answer: The volume of air remaining in the lungs after maximal exhalation.[](https://www.ncbi.nlm.ni
2.8 What is Functional Residual Capacity (FRC)?
Answer: The volume of air in the lungs at the end of a normal exhalation.[](https://www.ncbi.nlm.nih.g
3
Update 2024/2025, 100% Verified
Introduction
This document provides a comprehensive set of questions and answers related to Pul-
monary Function Tests (PFTs) for the 2024/2025 academic year. It is designed to assist
students, healthcare professionals, and educators in understanding key concepts, proce-
dures, and interpretations associated with PFTs. The content focuses on essential topics,
eliminating unnecessary jargon, and includes 100 additional relevant questions to enhance
learning.
1 Spirometry Basics
1.1 What is the purpose of performing PFTs?
Answer: PFTs evaluate lung functions, volumes, ventilation, diffusing capacity, and
metabolic aspects to diagnose lung diseases, assess therapy, and quantify disease severity.
1.2 What is the American Thoracic Society standard for volu-
metric accuracy of spirometers?
Answer: ś3% error or within 50 mL of the reference value.[](https://www.stuvia.com/en-
us/doc/5989985/pft-final-exam-with-100-correct-answers-2024)
1.3 Which test is used as an indicator of ventilatory inspiratory
muscle strength?
Answer: Maximal Inspiratory Pressure (MIP).[](https://www.stuvia.com/en-us/doc/7125079/pft-
final-exam-questions-and-answers-latest-update-2025.docx)
1.4 What is the most important measurement for distinguishing
an obstructive impairment?
Answer: FEV1/VC ratio.[](https://www.stuvia.com/en-us/doc/7285347/pft-final-exam-
2025-100-correct-answers)
1.5 What are the indications for spirometry?
Answer: Diagnose lung disease, assess occupational/environmental exposure, evaluate
therapy, monitor disease progression, assess surgical risk, quantify disability, and support
1
,clinical research.[](https://www.stuvia.com/en-us/doc/8262839/pft-final-exam-updated-
actual-exam-questions-and-correct-answers)
1.6 What is the normal range for the FEV1/FVC ratio in healthy
adults?
Answer: Greater than 0.70.[](https://www.ncbi.nlm.nih.gov/books/NBK482339/)
1.7 What does a low FEV1/FVC ratio indicate?
Answer: An obstructive ventilatory defect.[](https://www.aafp.org/pubs/afp/issues/2014/0301/p359.h
1.8 How is spirometry performed?
Answer: The patient takes a maximal inspiration, followed by a forceful exhalation
(blast) and continues to exhale completely.[](https://www.ncbi.nlm.nih.gov/books/NBK482339/)
1.9 What are the three phases of spirometry?
Answer: Maximal inspiration, a blast of exhalation, and complete exhalation to the end
of the test.[](https://www.ncbi.nlm.nih.gov/books/NBK482339/)
1.10 What is the Forced Vital Capacity (FVC)?
Answer: The total volume of air exhaled during a forced maneuver.[](https://www.ncbi.nlm.nih.gov/bo
1.11 What is Forced Expiratory Volume in 1 second (FEV1)?
Answer: The volume of air exhaled in the first second of a forced maneuver.[](https://www.ncbi.nlm.nih
1.12 What is the significance of a slow vital capacity (VC)?
Answer: It measures the total volume of air exhaled slowly, often higher than FVC
in obstructive diseases due to less airway compression.[](https://www.stuvia.com/en-
us/doc/7285347/pft-final-exam-2025-100-correct-answers)
1.13 What is the Wright Respirometer used for in PFTs?
Answer: It measures Slow Vital Capacity.[](https://www.stuvia.com/en-us/doc/7125079/pft-
final-exam-questions-and-answers-latest-update-2025.docx)
1.14 What is the acceptable variability between spirometry tri-
als?
Answer: Results of the two best efforts should be within 0.2 L of each other.[](https://www.aafp.org/pub
2
, 1.15 What indicates a good quality spirometry test?
Answer: A volume-time curve reaching a plateau, expiration lasting at least six seconds,
and flow-volume loops free of artifacts.[](https://www.aafp.org/pubs/afp/issues/2014/0301/p359.html)
2 Lung Volume and Capacity
2.1 What is Respiratory Dead Space?
Answer: Lung volume that is ventilated but not perfused by pulmonary capillary blood
flow, including anatomical and alveolar dead space (physiological dead space).[](https://www.stuvia.com
us/doc/7125079/pft-final-exam-questions-and-answers-latest-update-2025.docx)
2.2 What is the calculation for Alveolar Ventilation?
Answer: (VCO2/PaCO2) Π0.863.[](https://www.stuvia.com/en-us/doc/7125079/pft-
final-exam-questions-and-answers-latest-update-2025.docx)
2.3 What is the normal minute ventilation?
Answer: 510 L/min.[](https://www.stuvia.com/en-us/doc/7125079/pft-final-exam-questions-
and-answers-latest-update-2025.docx)
2.4 What conditions cause a quick increase in dead space?
Answer: Pulmonary emboli, pulmonary hypertension, and conditions causing drastic
shortness of breath.[](https://www.stuvia.com/en-us/doc/7125079/pft-final-exam-questions-
and-answers-latest-update-2025.docx)
2.5 What is the indication for lung volume testing?
Answer: To diagnose restrictive lung disease, assess hyperinflation, differentiate obstruc-
tive vs. restrictive patterns, and standardize other lung function measures.[](https://www.stuvia.com/en
us/doc/8262839/pft-final-exam-updated-actual-exam-questions-and-correct-answers)
2.6 What is Total Lung Capacity (TLC)?
Answer: The total volume of air in the lungs after maximal inspiration.[](https://www.ncbi.nlm.nih.gov
2.7 What is Residual Volume (RV)?
Answer: The volume of air remaining in the lungs after maximal exhalation.[](https://www.ncbi.nlm.ni
2.8 What is Functional Residual Capacity (FRC)?
Answer: The volume of air in the lungs at the end of a normal exhalation.[](https://www.ncbi.nlm.nih.g
3
