Respiratory Flashcards
(40 cards)
What are morphologic pulmonary assessment tools?
radiology, bronchoscopy, biopsy, sputum
What are physiologic pulmonary assessment tools?
PFTs, blood gas analysis
Bronchoscopy
direct visualization of the airway
Biopsy
obtaining a tissue sample
Sputum
lower airway mucus produced by inflammation
Radiology
CXR
CT scan
VQ (ventilation/perfusion)
MRI- not commonly used
PET scan- nuclear scan that looks at metabolic changes on a molecular level
What can be visualized in a bronchoscopy?
proximal airways. distal airways are often not accessible
What is bronchoscopy used for?
Obtain biopsies, retrieve foreign bodies, control bleeding or remove secretions, can place stents in the event of obstructing lesion
What are the two types of sputum studies and what do they evaluate?
- culture- evaluates bacteria or fungal organisms causing infection. Helps target antibiotic therapy, detects TB via an acid-fast bacilli (AFB) smear and culture
- cytology- look for abnormal cells under a microscope. noninvasive way to evaluate for cancerous cells-not typically used alone. Sensitivity is low, specificity nears 100%
What is a CT scan?
series of XR images taken at different angles and then manipulated by a computer screen to create cross-section images. 3D view.
What does a CT scan rely on?
relies on densities of different tissues- variations of grey.
bone=white
air=black
When do you need to have contrast for a CT scan?
need contrast to evaluate pulmonary elbolism.
if looking for infection, edema, effusion, nodules, it is not required
What is a VQ scan?
uses radioactive substance to evaluate the flow of air and blood through the lungs (inhaled and injected)
What is a VQ scan most commonly used for?
- To evaluate for pulmonary embolism
V>Q because there are blood clots blocking the flow of blood - Can see changes in other lung diseases
- For patients who cannot have IV contrast for CT scan (renal insufficiency or allergy)
What does a pulse ox estimate?
how saturated with oxygen peripheral blood is
What are ways in which the pulse ox can be wrong?
nail polish
darker skin
smoking
cold extremities
When in doubt when using a pulse ox, what would be a more reliable test to do?
ABG
What does a PFT measure?
measures ventilatory function or gas diffusion
illustrates effects of disease on lung function
allows for assessment of disease progression
evaluates efficacy of treatment
What does ventilatory function tests measure?
- lung volumes and lung capacities. Volume of gas in the lungs during different parts of the respiratory cycle. Some are measured and some are calculated.
- diffusion capacities
- restrictive disease (lung expansion problems) or obstructive disease (flow problems)
- measured by spirometry and formulas
Tidal volume (TV)
amount of air inhaled/exhaled in 1 breath at rest (normal breathing)
Inspiratory reserve volume (IRV)
max amount of air inhaled above TV inhalation
Expiratory reserve volume (ERV)
max amount of air exhaled below TV expiration
Residual volume (RV)
amount of air left after maximum exhalation. Tested by inhaling 100% oxygen or helium and taking measurements
What are the four lung capacities that are measured?
Vital capacity (VC): forced vital capacity (FVC) is the max amount of air exhaled after max inhalation
Total lung capacity (TLC): max amount of air in the lungs after max amount inhalation (also equals VC plus RV)
Inspiratory capacity (IC): max amount of air inhaled after normal exhalation
Functional reserve capacity (FRC): volume of air remaining in the lungs after a normal total volume exhalation
