Physiology Quiz 6 (Resipratory) Flashcards
Intrapleural pressure
Pressure within thoracic cavity
Interpulmonic pressure
Pressure within lungs
Intraplural pressure is always….
Negative
Contraction of diaphragm does what
Increase pressure in thoracic cavity and lungs
Tidal volume
Volume of air inhaled and exhaled
Typical value of tidal volume
500mL; will increase with exercise
Dead space
Regions not involved in gas exchange
When Vidal volume is taken in a portion of the air goes to dead space
Types of dead space
Anatomic
Physiologic
Anatomic dead space
Volume of respiratory tree that does not normally participate in gas exchange which is supplied with air from tidal volume
Typical volume of anatomic dead space
150ml
Physiologic dead space
Volume in the lung which normally participates in gas exchange that is supplied with air but is not now participating in gas exchange
How does physiological dead space occur
Small bronchiole closes off (usually by mucous plug) and area distal to that blockage no longer participates in gas exchange
Sigh reflex
Deeper than normal tidal breath, counters atelectasis
Atelectasis
Something causing small bronchiole to become closed off
What counters atelectasis
Sigh reflex
Exercise with hyperpnea
What diseases are associated with atelectasis
COPD
emphysema
Inspiratory reserve volume
Maximal volume that can be inhaled at he end of a normal tidal volume
Inspiratory reserve volume decreased in what populations
COPD
Smokers
Emphysema
Asthma
Expiratory reserve volume
Maximal amount of air that can be exhaled at the end of normal tidal volume
Expiratory tidal volume decreased in what populations
COPD
smokers
Asthma
What is a more sensitive indicator of pulmonary dysfunction
Expiratory reserve volume
What happens to the bronchiole with asthma
Constricte; inhibits air flow
What does respiratory bronchiole do
Collapses in forced expiration to not allow air to leave alveolar clusters; happens sooner in emphysema and COPD
Eupnea
Quiet breathing at rest
Hyperpnea
Increased rate and depth of breathing
Vital capacity
Sum of
Inspiratory reserve volume
Expiratory reserve volume
tidal volume
Vital capacity is reduced in what populations
COPD
smokers
Residual volume
Volume of air that can never be expelled
Residual volume is larger in what populations
COPD
smokers
Forced exploratory volume
Volume that can be expelled
FEV 1
FEV 2
FEV 1
Volume of air that can be expelled during first second (~70% vital capacity)
FEV 2
Volume of air that can be expelled during the first 3 sec (~90% vital capacity)
Forced expiratory volume is reduced in what populations
COPD
asthma
Smokers
