What are the recommended steps for a pregnant female experiencing shortness of breath (dyspnea)?

Management of Shortness of Breath in Pregnancy

For a pregnant woman experiencing shortness of breath, immediately assess oxygen saturation and distinguish between physiologic dyspnea of pregnancy versus life-threatening conditions like pulmonary embolism, peripartum cardiomyopathy, or asthma exacerbation—then treat aggressively as uncontrolled respiratory disease poses far greater fetal risk than any diagnostic test or medication. 1, 2

Immediate Assessment

Obtain oxygen saturation immediately and maintain SpO2 >95% with supplemental oxygen as needed. 2 Position the patient in left lateral tilt to optimize venous return and cardiac output. 2

Critical Red Flags Requiring Urgent Evaluation

The following symptoms demand immediate workup and cannot be dismissed as physiologic dyspnea: 2, 3

• Severe dyspnea at rest (not just with exertion)
• Chest pain, particularly pleuritic
• Syncope or presyncope
• Hemoptysis
• Palpitations or unexplained hypotension
• Oxygen desaturation (SpO2 <95%)
• Tachypnea at rest (>20 breaths/min)
• Unilateral leg swelling (suggests DVT/PE)

Differential Diagnosis Priority

The differential includes physiologic dyspnea of pregnancy, pulmonary embolism (the leading cause of pregnancy-related maternal death in developed countries, occurring in 1 per 1000-3000 deliveries), peripartum cardiomyopathy, pre-existing cardiac disease, asthma exacerbation, and pneumonia. 2, 3

When to Suspect Pulmonary Embolism

PE must be aggressively excluded in pregnancy given its status as the leading cause of maternal death. 2, 3 Pregnancy creates a hypercoagulable state through increased coagulation factors and decreased venous flow from uterine compression. 3

Critical pitfall: Do NOT rely on D-dimer to exclude PE in pregnancy—it has inadequate sensitivity (73%) and poor specificity (15%) with a negative likelihood ratio of 1.8. 2

Diagnostic Algorithm for Suspected PE

If signs/symptoms of DVT are present (unilateral leg swelling, pain): 3

1. Perform bilateral lower extremity compression ultrasound FIRST
2. If positive for DVT: Start therapeutic-dose low molecular weight heparin immediately—no further imaging needed 2, 3
3. If negative: Proceed to pulmonary imaging

If no signs/symptoms of DVT: 3

1. Obtain chest X-ray for risk stratification (normal results do NOT exclude PE) 2, 3
2. Proceed directly to pulmonary vascular imaging
3. Do not withhold indicated imaging due to radiation concerns—fetal radiation doses from chest radiograph and CT are well below the 50 mSv safety threshold for fetal harm 2, 3

Management of Asthma-Related Dyspnea

Never discontinue asthma medications during pregnancy—poorly controlled asthma increases risks of preeclampsia, preterm birth, low birthweight, gestational diabetes, and perinatal mortality far more than the medications themselves. 4, 1

Acute Asthma Exacerbation Treatment

For acute symptoms or exacerbations: 4, 1

• Albuterol nebulizer 2.5-5 mg every 20 minutes for up to 3 doses, then every 1-4 hours as needed
• Albuterol is the preferred short-acting beta-agonist in pregnancy due to extensive safety data 1
• Add ipratropium bromide for severe exacerbations: 1.5 mL (containing 0.5 mg ipratropium + 2.5 mg albuterol) every 20 minutes for 3 doses, then every 2-4 hours 1
• Critical: Do not use ipratropium as monotherapy—always combine with beta-agonist 1

Maintenance Therapy for Persistent Asthma

Budesonide is the preferred inhaled corticosteroid during pregnancy (FDA Pregnancy Category B with most extensive safety data): 1

• Low dose: 200-600 mcg daily
• Medium dose: 600-1,200 mcg daily
• High dose: >1,200 mcg daily

For optimal nebulizer delivery, dilute aerosols to minimum 3 mL at gas flow of 6-8 L/min. 1

Key Safety Principle

It is safer for pregnant women with asthma to be treated with asthma medications than to have asthma symptoms and exacerbations. 4 Inadequate control of asthma poses greater risk to the fetus than asthma medications. 4, 1

Cardiac Causes of Dyspnea

Significant SOB during otherwise normal pregnancy can be associated with subtle cardiac involvement, including increased wall thickness, elevated pulmonary artery pressures, and diastolic dysfunction. 5 Peripartum cardiomyopathy must be considered in patients presenting with shortness of breath and lower extremity edema postpartum. 6

For suspected cardiac disease: 2

• Beta blockers for rate control in mitral stenosis
• Diuretics for pulmonary congestion
• Multidisciplinary cardio-obstetrics team management

Management During Labor and Delivery

Continue all asthma medications during childbirth. 1 Use early epidural analgesia with local anesthetics as the preferred method for pain management to reduce anxiety, maternal stress, and avoid respiratory depression. 1

Maintain vigilance for 24-48 hours postpartum, as this period represents a critical high-risk window for cardiorespiratory decompensation. 2, 3

Monitoring Requirements Throughout Pregnancy

For patients with asthma: 1

• Monthly assessment of asthma symptoms and lung function
• Serial ultrasound examinations starting at 32 weeks for suboptimally controlled or moderate-to-severe asthma
• Peak flow meter monitoring for home management
• Attention to fetal activity and movement

Common Pitfalls to Avoid

• Never dismiss dyspnea as "just pregnancy" without excluding life-threatening causes 2, 3
• Never discontinue asthma medications during pregnancy 1
• Never rely on D-dimer alone to exclude PE 2
• Never withhold indicated chest imaging due to radiation concerns—the risk of missing PE far outweighs minimal radiation exposure 2, 3
• Avoid excessive beta-agonist use, which may cause maternal/fetal tachycardia, maternal hyperglycemia, and neonatal hypoglycemia 1

Physiologic Dyspnea of Pregnancy

If physical examination is completely normal with no red flags, reassurance is appropriate as mild exertional dyspnea is a common physiological adaptation to pregnancy. 3 However, patients should be instructed to seek immediate care if they develop chest pain, severe dyspnea at rest, palpitations, syncope, or signs of fluid overload. 3