Cardiopulmonary Anatomy & Physiology Chapter 5: Pulmonary Function Measurements

the role the lungs play in gas exchange is known as

Pulmonary Function

these are practical applications of respiratory physiology; Necessary for understanding abnormal lung function and efficacy of treatment

Pulmonary Function Tests (PFTs)

PFTs assess the combined function of... (4 things)

-airways

-alveolar-capillary membrane

-respiratory muscles

-neural control mechanisms

refers to the measurement of volumes and capacities when no airflow is present

Static Lung Volumes and Capacities

what are the 5 physical characteristics that influence PFTs and predict normal test values?

-age

-gender

-height

-ethnicity

-body size/body surface area

to be considered normal, PFT values must be within what percent of the predicted value?

20%

Can the Residual Volume (RV) be exhaled?

No

True or False: The Residual Volume (RV) can be directly measured.

False; RV must be indirectly measured

Name the 3 methods used to indirectly measure Residual Volume (RV)

-Helium dilution method

-Nitrogen washout method

-Body plethysmography method

what does an increased Functional Residual Capacity (FRC) indicate?

hyperinflation

what does an increased Functional Residual Capacity (FRC) AND an increased Residual Volume (RV) indicate?

obstructive disease (air trapping)

what does a decreased Functional Residual Capacity (FRC) AND a decreased Residual Volume (RV) indicate?

Restrictive disease (high elastance)

What does RV/TLC represent?

the percentage of the Total Lung Capacity (TLC) that is Residual Volume (RV)

if there is an increase in Residual Volume (RV), how will RV/TLC ratio be affected?

RV/TLC ratio will increase

reflects the ability of the lungs to move air rapidly, facilitating the detection of airway obstruction and increased airway resistance

Dynamic Measurements

Do dynamic measurements mainly involve inspiratory or expiratory flows?

expiratory flows

PFT measurement that requires the patient to exhale the Vital Capacity (VC) as forcefully and rapidly as possible, using maximum effort.

Forced Vital Capacity (FVC)

what validates a FVC measurement?

patient must perform 3 FVC maneuvers with variations no greater than 5%

this is characterized by increased airway resistance; FVC exhalation requires more time due to decreased flow rate

airway obstruction

decreased FVC due to low lung compliance is seen in what kind of disease?

Restrictive disease

True or False: Forced Vital Capacity (FVC) and Slow Vital Capacity (SVC) are nearly equal in normal individuals.

True

the amount of the FVC exhaled in the 1st, 2nd, and 3rd second is known as...

Forced Expiratory Volume (FEV: FEV1. FEV2, FEV3)

the fraction (percentage) of the FVC that is exhaled in the 1st, 2nd, and 3rd second is known as...

FEV% or FEV/FVC ratio

what is the normal FEV1 percentage?

83% of the FVC

FEV1 is an index of severity in what patients?

COPD

what does a low FEV1% indicate?

Airway obstruction (increased airway resistance)

airway obstruction is present if FEV1% is less than...

70%

Resistance to expiratory flow of the FVC; rates are derived from the volume-time FVC curve.

Forced Expired Flow (FEF)

the average flow rate over the middle 50% of the FVC in small airways.

FEF25%-75%

expiratory flow between the first 200-1200mL in larger airways

FEF200%-1200%

the maximum attainable expiratory flow rate during a FVC maneuver is called

Peak Expiratory Flow (PEF) or Peak Flow (PF)

Peak Expiratory Flow (PEF, PF) is determined by...

large airway diameter

True or False: Peak Expiratory Flow is an effort dependent test.

True (Best out of 3 maneuvers)

name the main pulmonary function characteristic of Obstructive Diseases

decreased expiratory flow

name the mechanism of Obstructive Diseases that increases work of breathing

High airway resistance

name the main pulmonary function characteristic of Restrictive Diseases

Decreased Volumes and Capacities

name the mechanism for increasing work of breathing in Restrictive Diseases

low lung compliance

on a FVC flow-volume curve, the expiratory (above baseline) flow and inspiratory (below baseline) flow form the...

Flow-Volume Loop

the greatest volume of air a person can move in and out of the lungs with max effort over 10-15 seconds is known as...

Maximum Voluntary Ventilation (MVV)

True or False: Maximum Voluntary Ventilation (MVV) is a non-specific test

True

What does Maximum Sustainable Ventilation evaluate?

endurance