Midterm Flashcards
absolute shunt
The sum of anatomic shunt and capillary shunt. It is refractory to oxygen therapy.
accessory muscles
Muscles not normally used during quiet breathing that are available for assisting either inspiration or expiration during times of increased work of breathing.
acids
Substances that dissociate or lose ions.
acute respiratory distress syndrome (ARDS)
A type of respiratory failure caused by diffuse injury to the alveolar-capillary membrane, resulting in noncardiogenic pulmonary edema.
air trapping
The abnormal retention of air in the lungs on exhalation.
anatomic shunt
Movement of blood from the right heart and back into the left heart without coming into contact with alveoli.
base excess
A measure of the amount of buffer required to return the blood to a normal pH state. It is used in reference to metabolic acid-base states. A person can develop a base excess (metabolic alkalosis) or a base deficit (metabolic acidosis).
bases
Substances capable of accepting ions.
buffer
A substance that reacts with acids and bases to maintain a neutral environment of stable pH.
capillary shunt
Normal flow of pulmonary blood past completely unventilated alveoli.
capnogram
Graphic representation of carbon dioxide levels during respiration.
capnometry
Measurement of carbon dioxide in expired gas.
carina
The junction of the Y formed by the right and left mainstem bronchi in the lungs.
compensated
A state in which the pH is within normal limits with the acid-base imbalance being neutralized but not corrected.
compliance (CL)
Measurement of the relative ease with which an organ can expand; reflects relative stiffness of the organ; in the lungs, it is the amount of force required to expand the lungs; measured in mL/cm H2O; normal is 50 to 100 mL/cm H2O.
cor pulmonale
Right ventricular hypertrophy and dilation secondary to pulmonary disease, resulting in pulmonary hypertension.
corrected
A state in which all acid-base parameters have returned to normal ranges after a state of acid-base imbalance.
crackles (rales)
Adventitious breath sounds associated with fluid or secretions or both in small airways or alveoli.
diffusion
Movement of gases across a pressure gradient from an area of high concentration to one of low concentration.
dyspnea
Subjective sensation of difficulty breathing.
end-tidal carbon dioxide (PETCO2 or ETCO2)
Concentration of carbon dioxide at the end of exhalation.
external respiration
Movement of gases across the alveolarcapillary membrane.
forced expiratory volume (FEV)
Measure of how rapidly a person can forcefully exhale air after a maximal inhalation; a measurement of dynamic lung function.
hemoptysis
Expectoration of bloody sputum.