PREMID Flashcards
The most important function of the lungs is _____.
gas ex- change
- The diaphragm and thoracic muscles must be capable of expanding the thorax and lungs to produce a subatmo- spheric pressure.
- The airways must be unobstructed to allow gas to flow into the lungs and reach the alveoli.
- O2 and CO2 must be able to diffuse through the alveolar- capillary membrane.
- The cardiovascular system must circulate blood through the lungs and ventilated alveoli.
ability of the lungs to perform gas exchange
_______ can provide valuable information
about these important individual processes that support gas exchange.
Pulmonary function tests
Various _______ are available to aid in the diagnosis and assessment of pulmonary diseases, to determine the need for therapy, and to evaluate the effectiveness of respira- tory care.
measurements
For ________ , knowledge of these tests and the ability to interpret the measurements are essential for assessing patients objectively and for planning and imple- menting effective patient care.
respiratory therapists (RTs)
A complete evaluation of the respiratory system includes a ____
patient history, physical examination, radiographic imaging, arterial blood gas analysis, and tests of pulmonary function.
Although diagnostic ______ is performed in a laboratory setting and usually only on patients in a stable condition, RTs also perform many of these tests at the bedside on patients who are acutely ill or being evaluated for surgical readiness.
pulmonary function testing
There are three categories of pulmonary function tests, measuring ________123
(1) dynamic flow rates of gases through the airways,
(2) lung volumes and capacities, and
(3) the ability of the lungs to diffuse gases.
A combination of these measurements provides a quantitative picture of ______
lung function.
Although ______ do not diagnose specific pulmonary diseases, these tests identify the presence and type of pulmonary impairments and the degree of pulmonary disease present.
pulmonary function tests
Some basic tests of pul- monary function are often performed at the _____ to provide immediate information about the need for _______ and its effectiveness.
bedside / respiratory therapy
Generally, the primary purposes of pulmonary function testing are to identify ____ and _____
pulmonary impairment and quantify the severity of pulmonary impairment if present.
_____ has diagnostic and therapeutic roles and helps clinicians answer some general questions about patients with lung disease
Pulmonary function testing
• Is lung disease present?
• What type of lung impairment is present?
• What is the degree of lung impairment?
• Is more than one type of lung impairment present?
• Can multiple lung diseases be separated?
DIAGNOSTIC
• Is therapy indicated?
• What treatments are most effective?
• To what degree is the disease reversible?
• Can treatments be evaluated?
• Is rehabilitation feasible?
THERAPEUTIC
The indications for pulmonary function testing are as follows
• To identify and quantify changes in pulmonary function.
• To evaluate need and quantify therapeutic effectiveness.
• To perform epidemiologic surveillance for pulmonary disease.
• To assess patients for risk for postoperative pulmonary compli- cations.
• To determine pulmonary disability.
The most common purposes of pulmonary function testing are to detect the presence or absence of pulmonary disease, to classify the type of disease as either obstructive, restrictive, or both (mixed), and to quantify the severity of pulmonary impairment as mild, moderate, severe, or very severe. Over time, pulmonary function tests help quantify the progres- sion or the reversibility of the disease.
To identify and quantify changes in pulmonary function.
Pulmonary function tests may aid clinicians in selecting or modifying a specific therapeutic regimen or technique (e.g., bronchodilator medication, airway clearance therapy, reha- bilitation exercise protocol). Clinicians and researchers use pulmonary function tests to measure changes in lung func- tion objectively before and after treatment.
To evaluate need and quantify therapeutic effectiveness.
Screening programs may detect pulmonary abnormalities caused by disease or environmental factors in general popu- lations, in people in occupational settings, in smokers, or in other high-risk groups. In addition, researchers have deter- mined what normal pulmonary function is by measuring the pulmonary function of healthy people.
To perform epidemiologic surveillance for pulmonary disease.
Preoperative testing can identify patients who may have an increased risk for pulmonary complications after surgery. Sometimes the risk for complications can be reduced by preoperative respiratory care, or in some cases, the risk may be significant enough to rule out surgery.
To assess patients for risk for postoperative pulmonary compli- cations.
Pulmonary function tests can also determine the degree of disability caused by lung diseases, such as occupational asthma or coal workers’ pneu- moconiosis. Some federal entitlement programs and insur- ance policies rely on pulmonary function tests to confirm claims for financial compensation.
To determine pulmonary disability.
There are also contraindications to pulmonary function testing. Patients with acute, _________ should not be tested.
unstable cardiopulmonary problems, such as hemoptysis, pneumothorax, myocardial infarction, pulmonary embolism, and patients with acute chest or abdominal pain
Patients who have ___ and who have ____ should not be tested because there is a risk of aspiration.
nausea / recently vomited
Testing for patients who have had recent ______ should be delayed because changes in ocular pressure may be harmful to the eye.
cataract removal surgery
Pulmonary function testing requires patient ____ and ____
effort and cooperation.
Patients with ___ or ____ may not achieve optimal or repeatable results.
dementia or confusion
_____ should not be performed if valid and reliable results cannot be predicted.
Pulmonary function testing
In patients who are acutely ill or who have recently smoked a ciga- rette, the test validity of measuring the ______ may be hindered.
forced vital capacity (FVC)
Pulmonary function testing provides the basis for classifying pulmonary diseases into two major categories, ____ and ______
obstructive pulmonary disease and restrictive pulmonary disease.
These two types of lung diseases sometimes occur together as a mixed impairment.
obstructive pul- monary disease and restrictive pulmonary disease.
The primary problem in ______ is an increased airway resistance (Raw).
obstructive pulmonary disease
____ is the difference in pressure between the ends of the airways divided by the flow rate of gas moving through the airway
Raw
There is an inverse relationship between Raw and _____
flow rate V.
If the pressure difference is constant, a reduced flow rate indicates an _____.
increase in Raw
the ____ of the airways normally lessens slightly during expiration,
radius
_____ are usually measured during expiration.
flow rates
According to ______ , Raw is inversely related to the radius (r) of the airways
Poiseuille’s law