Pulmonary Flashcards
What is vital capacity?
Inspiratory capacity + expiratory reserve volume
What is TLC defined?
VC + RV
How does vital capacity change in pregnancy?
VC: 20% increase
How does total lung capacity change in pregnancy?
TLC: 5% decrease
How does functional residual capacity change in pregnancy?
FRC: 20% decrease (expanding uterus and increased abdominal pressure cause chest wall compliance to decrease, so FRC (ERV+RV) decreases
How does inspiratory capacity change in pregnancy?
IC: 20% increase
How does tidal volume change in pregnancy?
TV: 500->700mL = 40% increase due to respiratory stimulant properties of progesterone
How does minute ventilation change in pregnancy?
MV: 7.5->10.5L/min = 40% increase due to increased tidal volume
How does alveolar ventialtion change in pregnancy?
Alveolar ventilation: 40% increase
How does expiratory reserve volume change in pregnancy in regards to ERV
ERV: 15% decrease
How does residual volume change in pregnancy?
RV: 1200->1000mL =15% decrease
How does respiratory rate change in pregnancy?
RR: unchanged
How does PaCO2 change in pregnancy?
PaCO2: decreases from 40 to 32 mmHg; pH 7.44-mild respiratory alkalosis (CO2 production increases approx 30%, but diffusion capacity increases, and with alveolar hyperventilation, the pCO2 decreases)
How is pulmonary hypertension defined in nonpregnant individuals?
Mean pulmonary pressure > 25 mmHg
What medications are used for primary pulmonary hypertension?
Diuretics, supplemental oxygen, vasodilator drugs
Choices from 2009 exam: Labetalol, Viagra, Hydralazine, CCB)
