Special Diagnostic Testing in Cardiopulmonary Disease Flashcards
(95 cards)
process by which air moves from the atmosphere into the lungs and into the alveoli
ventilation
what does V represent
ventilation
in most general terms, ventilation is ____ and ____
inspiration and expiration
pressure difference exists between the trachea and alveoli from ____
terminal bronchioles
during ventilation, there is a contraction of ________
inspiratory muscles
the inspiratory muscles are ______ and ______
diaphragm and intercostals
the contraction of inspiratory muscles during ventilation leads to a ____ of intrathoracic pressure
decrease
alveoli expand which will ____ their pressure
decrease
inspiration occurs resulting from….
negative pressure from intrathoracic cavity by muscles contracting and space getting bigger
definition: when gas exchange across alveoli increases
hyperventilation
definition: movement of blood through an area
perfusion
perfusion is represented by _
Q
perfusion is _______ dependent
gravity
how long does it take to oxygenate?
a fraction of a second
during perfusion, the right ventricle moves blood to ______
pulmonary artery
during perfusion, the left ventricle moves blood to ____ and then to ____
bronchial branch –> bronchial tree
what is the V-Q Scan
uses radioactive gas and dye delivered via injection and inspiration
when is the V-Q Scan performed
when a pulmonary embolism is suspected
what does the V-Q Scan measure
ventilation and perfusion
what is the normal V/Q ratio
0.8-1.2
must V and Q be matched at the alveolar-capillary level?
yes
where is the V-Q Scan optimal
mid-portion of the lung
why is the mid-portion of the lung most optimal for the V-Q Scan
good balance of gravity affecting lung
what occurs simultaneously as V and Q
diffusion
