Nurs 5315: Adv Patho Exam 3 Set 2
Accessory muscles of inspiration - ANS-sternocleidomastoid and scalene muscles
\airway resistance - ANS-dependent on the length, diameter, radius of airways and density,
viscosity, velocity of the gas exchange
normal = low
bronchodilation decreases airway resistance
bronchoconstriction increases airway resistance
\alveolar surface tension - ANS-promotes ease of breathing
\alveolar ventilation - ANS-The volume of air that reaches the alveoli.
Measured by PaCO2
It is determined by subtracting the amount of dead space air from the tidal volume.
\ARDS (acute respiratory distress syndrome) - ANS-PCWP <18, CXR with bilateral
pulmonary infiltrates, PaCO2:FiO2 ratio <200
Three phases:
1. inflammatory within 72 hours - inflammatory cascade, fluid, proteins and blood leak into
interstitium and alveoli, work of breathing increases, hypercapnia develops
2. proliferative phase - pulmonary edema resolves, surfactant produced again, 1-3 weeks;
intra-alveolar exudate turns into cellular granulation and worsens the hypoxemia
3. fibrotic phase - 14-21 days, alveoli undergo fibrosis, decrease in pulmonary function,
rsidual capacity and continued VQ mismatch
\barometric pressure - ANS-total pressure in the air exerted by all gas molecules
\Compliance of pulmonary ventilation - ANS-Ease with which the lungs and thoracic wall can
be expanded
determined by alveolar surface tension and chest wall elatic recoil
increases w/ COPD
decreases w/ ARDS, pneumonia, pulmonary edema
\Diaphragm - ANS-Large, flat muscle at the bottom of the chest cavity that helps with
inspiration
contracts > increased negative pressure in the lungs and draws air in
\Effective gas exchange requires: - ANS-equal distribution of ventilation and perfusion
clear airways
normal lungs and chest wall
adequate pulmonary circulation
\elastic recoil of the lungs - ANS-ability of the chest wall to return to normal after inspiration
generally passive
accessory muscles help if elastic recoil is not enough, i.e. COPD
\Exhalation - ANS-The passive part of the breathing process in which the diaphragm and the
intercostal muscles relax, forcing air out of the lungs.
\FEV1 - ANS-forced expiratory volume in 1 second
Normal 80-120%
\FEV1/FVC ratio - ANS-The fraction of air exhaled in the first second relative to the total
volume exhaled
\Function Residual Capacity (FRC) - ANS-the volume of air remaining in the lungs at the end
of a normal expiration
Accessory muscles of inspiration - ANS-sternocleidomastoid and scalene muscles
\airway resistance - ANS-dependent on the length, diameter, radius of airways and density,
viscosity, velocity of the gas exchange
normal = low
bronchodilation decreases airway resistance
bronchoconstriction increases airway resistance
\alveolar surface tension - ANS-promotes ease of breathing
\alveolar ventilation - ANS-The volume of air that reaches the alveoli.
Measured by PaCO2
It is determined by subtracting the amount of dead space air from the tidal volume.
\ARDS (acute respiratory distress syndrome) - ANS-PCWP <18, CXR with bilateral
pulmonary infiltrates, PaCO2:FiO2 ratio <200
Three phases:
1. inflammatory within 72 hours - inflammatory cascade, fluid, proteins and blood leak into
interstitium and alveoli, work of breathing increases, hypercapnia develops
2. proliferative phase - pulmonary edema resolves, surfactant produced again, 1-3 weeks;
intra-alveolar exudate turns into cellular granulation and worsens the hypoxemia
3. fibrotic phase - 14-21 days, alveoli undergo fibrosis, decrease in pulmonary function,
rsidual capacity and continued VQ mismatch
\barometric pressure - ANS-total pressure in the air exerted by all gas molecules
\Compliance of pulmonary ventilation - ANS-Ease with which the lungs and thoracic wall can
be expanded
determined by alveolar surface tension and chest wall elatic recoil
increases w/ COPD
decreases w/ ARDS, pneumonia, pulmonary edema
\Diaphragm - ANS-Large, flat muscle at the bottom of the chest cavity that helps with
inspiration
contracts > increased negative pressure in the lungs and draws air in
\Effective gas exchange requires: - ANS-equal distribution of ventilation and perfusion
clear airways
normal lungs and chest wall
adequate pulmonary circulation
\elastic recoil of the lungs - ANS-ability of the chest wall to return to normal after inspiration
generally passive
accessory muscles help if elastic recoil is not enough, i.e. COPD
\Exhalation - ANS-The passive part of the breathing process in which the diaphragm and the
intercostal muscles relax, forcing air out of the lungs.
\FEV1 - ANS-forced expiratory volume in 1 second
Normal 80-120%
\FEV1/FVC ratio - ANS-The fraction of air exhaled in the first second relative to the total
volume exhaled
\Function Residual Capacity (FRC) - ANS-the volume of air remaining in the lungs at the end
of a normal expiration
