[05.40] Pulmonary Diagnostics_ Spirometry V2.3.pdf

Spirometry

What is one of the four key procedures listed under Pulmonary Function Test (PFT)?

Lung Volume Studies

What PFT procedure is listed alongside Spirometry, Diffusing Capacity, and Arterial Blood Gas Analysis?

Diffusing Capacity

What PFT procedure is listed alongside Spirometry, Lung Volume Studies, and Arterial Blood Gas Analysis?

Arterial Blood Gas Analysis

What PFT procedure is listed alongside Spirometry, Lung Volume Studies, and Diffusing Capacity?

Interpret spirometry tracings & differentiate between obstructive, restrictive, & mixed pattern

What is the first learning objective listed for this topic?

Differentiate between intrathoracic vs extrathoracic obstructive pattern

What is the second learning objective listed for this topic?

Interpret Lung Volume studies and DLCO

What are two specific PFT procedures the learner should be able to interpret according to the learning objectives?

Total volume of air the patient can expel from the lungs after a maximal inhalation

What is the definition of Spirometry?

Hemoptysis of unknown origin

What specific condition is a contraindication for spirometry?

Pneumothorax

What condition involving air in the pleural space is a contraindication for spirometry?

Unstable angina pectoris

What cardiac condition is listed as a contraindication for spirometry?

Recent myocardial infarction

What recent cardiac event contraindicates spirometry?

Thoracic, abdominal, cerebral aneurysms

What three types of aneurysms contraindicate spirometry?

Recent abdominal or thoracic surgical procedures

What type of recent medical procedure contraindicates spirometry?

Recent eye surgery

What type of recent surgery contraindicates spirometry?

History of syncope associated with forced exhalation

What specific history related to forceful breathing contraindicates spirometry?

Intrathoracic, intraabdominal, and intraocular pressure

What three pressures can the forced vital capacity maneuver increase?

Smaller and more portable

What are two characteristics of modern spirometers compared to older ones?

Tidal Volume (TV)

What is the volume of air that is inspired and expired during normal quiet breathing?

Inspiratory Reserve Volume (IRV)

What is the maximum amount of air that can be inhaled after a normal tidal volume inspiration?

Expiratory Reserve Volume (ERV)

What is the maximum amount of air that can be exhaled from the resting expiratory level?

Residual Volume (RV)

What is the volume of air that remains in the lungs at the end of maximum expiration?

Inspiratory Capacity (IC)

What capacity is the sum of IRV and TV?

IRV and TV

IC is the sum of what two lung volumes?

Functional Residual Capacity (FRC)

What capacity is the sum of ERV and RV?

ERV and RV

FRC is the sum of what two lung volumes?

Vital Capacity (VC)

What capacity is the maximum volume of air which can be inhaled or expired during either a force (FVC) or a slow (VC) maneuver?

Total Lung Capacity (TLC)

What capacity is the sum of all lung volumes?

Volume-time curve

What type of curve is a spirogram?

Volumes

What is found on the y-axis of a spirogram?

Time

What is found on the x-axis of a spirogram?

Tidal Volume breathing

What is the first step in the performance of a forced expiratory and inspiratory maneuver?

Rapid inspiration to Total Lung Capacity (TLC)

What is the second step in the performance of a forced expiratory and inspiratory maneuver?

Forced expiration starts immediately

What is the third step in the performance of a forced expiratory and inspiratory maneuver?

Sustained plateau (6-12 seconds)

What is the required duration for the sustained plateau during the forced expiration maneuver?

Rapid and forced inhalation

What is the final step in the performance of a forced expiratory and inspiratory maneuver?

Forced Vital Capacity (FVC)

What parameter is the maximum volume of air that can be inhaled or exhaled during an FVC maneuver?

Forced Expired Volume in 1 Second (FEV1)

What parameter is the volume of air expired in the first second of maximal expiration after maximal inhalation?

Airflow limitation

What does the FEV1/FVC ratio provide a useful index of?

Downward curve

How does a water-sealed or rolling seal spirometer display expired volume?

Upward curve

How does a dry-wedge bellows spirometer display expired volume?

FEF25-75%

What parameter is the Forced Expiratory Flow at 25-75% of FVC?

Average expired flow over the middle half of the FVC maneuver

What does FEF25-75% represent?

More sensitive measure of small airway narrowing than FEV1

What characteristic makes FEF25-75% particularly useful?

Flow-volume curve

What type of display is the Maximal Flow-Volume Loop?

Inspiratory and expiratory flow

What is plotted on the y-axis of the flow-volume loop?

Volume

What is plotted on the x-axis of the flow-volume loop?

Tidal breathing

What does the small circle in the middle of the flow-volume loop represent?

Maximal Inspiratory Flow (MIF) curve

What curve is formed when the subject inhales fully until TLC?

Maximal Expiratory Flow (MEF) curve

What curve is formed when the patient exhales fully from the TLC until RV?

Peak Expiratory Flow (PEF)

What parameter is the maximal expiratory flow rate achieved?

Very early in the forced expiratory maneuver

When does PEF occur?

Blast the air out as forcibly and fast as possible

What is the crucial third step in performing the spirometry maneuver, requiring encouragement?

At least twice more

How many times should the spirometry procedure be repeated after achieving an adequate trace?

Three (3) readings within 150 mL or 5% of each other

What is the ideal target for repeated readings (reproducibility)?

Acceptability and reproducibility criteria

What two criteria must spirometry tracings be subjected to before interpretation?

At least six seconds of exhalation and/or a plateau in the volume-time curve

What defines a satisfactory exhalation according to the acceptability criteria?

Cough or glottic closure during the first second of exhalation

What artifact must be absent during the initial phase of exhalation?

Early termination or cutoff

What artifact is defined as stopping the exhalation too soon in the volume-time curve?

Extrapolated volume < 5% of the FVC or 0.15 L (150 mL)

What is the first criteria for a "Good Start"?

Time to PEF < 120 ms

What is the criteria for a "Good Start" related to sharp peak flow?

Slow start (gentle slope or rise)

What artifact in the volume-time curve is related to the initial gentle slope?

Variable expiratory effort

What artifact in the volume-time curve appears as a downward notch formed due to inhalation?

Coughing (variability in the expiratory curve)

What artifact is seen as large variability in the expiratory portion of the volume-time curve?

Extra Breath

What artifact appears as a sudden upward step in the plateau of the volume-time curve?

Stops prematurely or glottic closure

What artifact in the flow-volume curve results in the expiratory flow not reaching the baseline?

Tongue occlusion

What artifact results from the tongue blocking the mouthpiece?

Submaximal inspiration

What artifact in the flow-volume curve prevents PIF from being reached?

Not at TLC

What flow-volume curve artifact results in smaller but proportionate graphs?

Back Extrapolation Method

What method defines the zero time for FEV1 measurement?

0.15 L

What is the maximum allowed difference between the two largest FVC or FEV1 efforts for reproducibility?

8 tests

What is the maximum total number of tests allowed if reproducibility criteria are not met?

Largest sum of FVC and FEV1

How is the Best Test Curve defined?

Highest FEV1 and FVC

What two highest values should be reported, which may come from different efforts?

Slow rise, reduced volume expired, and prolonged time to full expiration

What three characteristics describe the volume-time pattern for Obstructive defects?

Fast rise to plateau at remarkably reduced maximum volume

What volume-time pattern is characteristic of a Restrictive defect?

Slow rise to reduced maximum volume

What volume-time pattern is characteristic of a Mixed defect?

Reduced peak flow, scooped out mid-curve

What two characteristics describe the flow-volume pattern for Obstructive defects?

Steeple pattern, reduced peak flow, rapid fall off

What three characteristics describe the flow-volume pattern for Severe Obstructive defects?

Normal shape, normal peak flow, reduced volume

What three characteristics describe the flow-volume pattern for Restrictive defects?

Thoracic inlet

What anatomical structure is the reference point for classifying upper airway obstructions?

Above the thoracic inlet

What location defines an extra-thoracic obstruction?

Below the thoracic inlet

What location defines an intra-thoracic obstruction?

Variable

What obstruction classification means the flow changes during inspiration or expiration?

Fixed

What obstruction classification means there is no flow change during inspiration or expiration?

Vocal cord paralysis, Glottic stricture, Tumors

What three examples are given for Variable Extra-thoracic obstruction?

Malignant tumors, Tracheomalacia

What two examples are given for Variable Intra-thoracic obstruction?

Goiter, Post-intubation stricture

What two examples are given for Fixed Extra- or Intra-thoracic obstruction?

Ptr < Patm

What is the relationship between tracheal pressure and atmospheric pressure during normal inspiration in the extra-thoracic region?

Negative

What is the state of the extra-thoracic tracheal pressure during inspiration, favoring narrowing of the lumen?

Worsen during inspiration

When will a variable extrathoracic obstruction worsen?

Augment its tendency to collapse

Why does a variable extrathoracic obstruction worsen during inspiration?

Worsen during expiration

When will an intrathoracic obstruction worsen?

Dynamic compression

Why does an intrathoracic obstruction worsen during expiration?

Flow-Volume Loop

What is the most important tool for the diagnosis of upper airway obstruction?

PEF, FIF50, FEF50

What three parameters are useful to differentiate between extra- or intra-thoracic variable obstruction?

↓

What is the expected PEF value for Variable Intrathoracic obstruction?

↓

What is the expected FIF
50
​
value for Variable Extrathoracic obstruction?

Close to 1

What is the expected FIF
50
​
/FEF
50
​
ratio for Fixed upper airway obstruction?

< 1

What is the expected FIF
50
​
/FEF
50
​
ratio for Variable Extrathoracic obstruction?