••• Chapter 14^ Management of Medical and Surgical Conditions in Pregnancy^135
PULMONARY CONDITIONS
❍ What is the prevalence of asthma in pregnancy?
4% to 8%.
❍ How often do symptoms occur in mild intermittent asthma?
Twice per week or less. Nocturnal symptoms may occur twice per month or less.
❍ What severity of asthma correlates with daily symptoms?
Moderate persistent asthma.
❍ What is the forced expiratory volume after 1 second (FEV1) in severe persistent asthma?
<60% of predicated, and variability >30%.
❍ What is the effect of pregnancy on asthma?
Approximately one-third of pregnant women’s asthma improve, 1/3 remain unchanged, and 1/3 worsen.
❍ How should pregnant women with asthma be monitored?
Women with moderate or severe asthma should measure their peak expiratory flow rate (PEFR) or FEV1 twice daily.
❍ What is the typical PEFR in pregnancy?
380 to 550 L/min. Women who are at >80% of their predicted PEFR require no additional treatment.
❍ How can asthma affect maternal and perinatal outcomes?
Women with severe asthma or who require use of oral corticosteroids have an increased risk of preterm delivery.
Asthma also increases the risk of preeclampsia, cesarean delivery, gestational diabetes, and small for gestational age
infants.
❍ What is the stepwise care therapeutic approach?
The goal is to use the least pharmacologic intervention that is required to control a patient’s asthma symptoms.
❍ When is a burst of oral corticosteroids indicated?
Exacerbations not responding to initial beta 2 agonists regardless of asthma severity.
❍ Describe a short course of oral corticosteroids.
Oral prednisone 40 to 60 mg per day for 1 week, followed by a 7 to 14-day taper.
❍ What is the preferred treatment of mild intermittent asthma?
Inhaled beta agonists as needed.
❍ What is the preferred treatment of pregnant women with persistent asthma?
Inhaled corticosteroids.