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Key Terms

airways
passageways through which gases move to and from the lungs
atelectasis
the collapse of the alveoli
auscultation
listening with a stethoscope for normal breath sounds, abnormal sounds, and voice sounds
crepitus
air trapped in and under the skin, typically felt as crackling
dyspnea
difficulty breathing, or breathlessness
fremitus
a vibration in the chest wall as the client speaks
gas exchange
oxygen being transported to the cells and carbon dioxide being transported away from the cells
Mallampati score
an airway assessment scale to classify the visibility of the oropharyngeal structures
orthopnea
shortness of breath that occurs when lying down and is relieved by sitting up
pack-years
the number of cigarettes or other smoke packs smoked per day multiplied by number of years smoked
percussion
a systematic tapping over the intercostal spaces, moving through the anterior, lateral, and posterior thorax
perfusion
the process of the arterial blood moving through tissues throughout the entire body
respiratory diffusion
occurs when gases move down the concentration gradient across the alveolar sacs and capillaries
surfactant
a fatty protein that lines the alveoli and reduces surface tension
ventilation
the movement of atmospheric air that is higher in oxygen into the lungs and removal of carbon dioxide
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