clinical scenario: volumes and capacities Flashcards
what is a spirometer?
mouthpiece that records the volume of air moved into or out of your lungs
what is the result of spirometry?
provide information about the volume of air moved into or out of your lungs, the rate at which this occurs, and the volume moved in a specific time, such as 1 second
list volumes of the lungs that of physiological importance
1) the volume of air you normally move into and out of your lungs as you breathe normally
2) the volume of air you could maximally pull into your lungs with the deepest breath possible
3) the volume of air you could force out of your lungs if you exhaled as hard as possible
4) volume of air that remains in your lungs even after you’ve exhaled as hard as possible
what is tidal volume?
when the volume of air moving in either direction is the same
what is inspiratory volume?
pulling as much air into your lungs as you can
what is inspiratory capacity?
combining the volume of air inspired during the tidal volume and the inspiratory reserve volume
what is the expiratory reserve volume?
maximal volume of air that you can breathe out after exhaling normally
what is the residual volume?
the volume of air that remains in your lungs after you’ve exhaled as hard as possible
what is the functional residual capacity?
expiratory residual volume and residual volume, volume of air remaining in your lungs after you breathe out normally.
what are the components of the lung that normally don’t collapse remaining from the residual volume?
bronchi, bronchioles, alveoli
what is vital capacity a combination of?
inspiratory volume + residual volume + expiratory volume
what vital capacity measure?
maximum volume of air you can force out of your lungs after you’ve inhaled as much as possible
what is total capacity a combination of?
residual volume, expiratory reserve volume, tidal volume and inspiratory volumes
what does total capacity measure?
reflects the total volume of air your lungs can hold
normal breathing is a reflection of which measurement?
tidal volume
deep inhale dips into which part of the spirometry graph?
inspiratory reserve volume
deep exhale dips into which part of the spirometry graph?
expiratory reserve volume
deep breathing uses which part of the spirometry graph?
vital capacity
what is forced vital capacity (FVC)?
the maximum volume of air that can be exhaled after the deepest breath possible has been taken
what is forced expiratory volume in one second or the FEV1?
the maximum volume of air can be exhaled in 1 second
what is the ratio that represents the percentage of the ‘functional’ lung volume that can be forcefully exhaled in 1 second?
FEV1/ FVC
what is the cause of narrowing of the bronchioles?
bronchoconstriction or bronchospasm: contraction of the smooth muscles that surround these small tubes
why is his wheezing worse during expiration?
inflammation of the bronchioles and accumulation of mucus
these processes severely reduce the internal diameter of the bronchioles making it much harder to exhale
what can cause wheezing from asthma?
house dust mites, pollens, mold, and animal dander
what are the two deleterious effects when IgE causes white blood cells in the tissues to secrete histamine?
1) contraction of the smooth muscles that surround the bronchioles
2) increased secretion of mucous that can occlude the lumen of the bronchioles.
why may patients with asthma have a decrease in blood pH?
CO2 levels in the blood increase since it is harder for them to get has in the alveoli out of their lungs
what is respiratory acidosis?
reduction in pH is due to an abnormality involving the respiratory system.
true or false: people with asthma will have reductions in both FEV 1 values and FEV 1 /FVC.
true
true or false: bronchodilators will have effects in patients with pulmonary diseases not characterized by bronchoconstriction
false
