How do I treat an asthmatic attack in a pregnant woman?

Treatment of Asthmatic Attack in Pregnant Women

The treatment of an asthmatic attack in a pregnant woman should follow standard asthma exacerbation protocols with albuterol as the first-line medication, administered via nebulizer (2.5-5 mg every 20 minutes for 3 doses) or MDI with spacer (4-8 puffs every 20 minutes for 3 doses), as it is safer to treat asthma aggressively than to allow hypoxia to affect the mother and fetus. 1

Initial Assessment and Treatment

1. Assess severity quickly:

   • Measure oxygen saturation (maintain >95%)
   • Evaluate respiratory rate, use of accessory muscles, ability to speak
   • Check peak flow if possible (aim for >70% of predicted)

2. First-line treatment:

   • Albuterol via nebulizer or MDI with spacer 1, 2
     • Nebulizer: 2.5-5 mg every 20 minutes for 3 doses, then 2.5-10 mg every 1-4 hours as needed
     • MDI with spacer: 4-8 puffs every 20 minutes for 3 doses, then every 1-4 hours as needed

3. For severe exacerbations:

   • Add ipratropium bromide 1
     • Nebulizer: 0.5 mg every 20 minutes for 3 doses, then as needed
     • MDI: 8 puffs every 20 minutes as needed up to 3 hours

4. Systemic corticosteroids for moderate to severe attacks 1

   • Prednisone 40-60 mg/day for outpatient treatment
   • 120-180 mg/day in 3-4 divided doses for 48 hours for severe exacerbations

Monitoring During Treatment

• Continuous pulse oximetry
• Reassess respiratory status every 20 minutes during initial treatment
• Monitor fetal heart rate if gestational age >24 weeks
• Repeat peak flow measurements to track improvement

Hospitalization Criteria

Consider hospital admission if: 1

• Failure to respond to initial emergency treatment
• PEF or FEV1 <70% of predicted after initial treatment
• Persistent hypoxemia
• History of severe asthma requiring intubation
• Presence of high-risk comorbidities

Special Considerations for Pregnancy

• Safety of medications: Albuterol has been used extensively during pregnancy with no evidence of significant fetal harm 1, 2
• Positioning: Treat in left lateral position when possible to avoid aortocaval compression in later pregnancy
• Oxygenation: Maintain maternal SpO2 >95% to ensure adequate fetal oxygenation
• Fluid management: Careful hydration to avoid both dehydration and fluid overload

Important Caveats

• Do not withhold treatment due to pregnancy concerns - untreated asthma poses greater risks to mother and fetus than medication side effects 1, 3
• Avoid systemic epinephrine if possible due to potential teratogenic effects and placental/uterine vasoconstriction 4
• Monitor potassium levels in severe cases requiring repeated albuterol dosing, as hypokalemia can occur 2
• Continue maintenance medications throughout pregnancy and during labor 3
• Be aware of potential drug interactions: Use albuterol with extreme caution in patients on MAOIs or tricyclic antidepressants 2

Follow-up After Acute Attack

1. Review and optimize maintenance therapy
2. Schedule follow-up within 1-2 weeks 1
3. Consider monthly monitoring of asthma status and pulmonary function throughout pregnancy 1
4. Provide a written asthma action plan specific for pregnancy 1
5. Consider serial ultrasound examinations starting at 32 weeks for patients with moderate to severe asthma 1

Remember that poorly controlled asthma during pregnancy increases risks of preeclampsia, preterm birth, low birth weight, and other complications 3, 5. Aggressive management of asthma exacerbations is essential for both maternal and fetal well-being.