Management of Mild Exertional Dyspnea at 28 Weeks Gestation

Clinical Presentation and Evaluation

The American College of Cardiology and other guideline societies recommend reassurance as the initial approach for patients with mild shortness of breath on exertion and a normal physical examination, as this presentation is a common physiological adaptation to pregnancy 1
A normal physical examination is key, as it effectively rules out the need for invasive testing in the absence of concerning features, such as oxygen desaturation, tachypnea, abnormal lung sounds, or signs of cardiopulmonary compromise 1

Severe dyspnea at rest, chest pain (particularly pleuritic chest pain), syncope or presyncope, hemoptysis, and palpitations or unexplained hypotension are symptoms that require immediate evaluation, according to the American Thoracic Society and the European Respiratory Society 2, 1
Oxygen desaturation with exertion (SpO2 <95%), tachypnea at rest (>20 breaths/min), persistent tachycardia, abnormal lung auscultation, and unilateral leg swelling are physical examination findings that require further workup, as recommended by the European Heart Journal and the American Journal of Respiratory and Critical Care Medicine 1, 3, 2

Pulmonary embolism remains the leading cause of pregnancy-related maternal death in developed countries, with an incidence of 1 per 1000 to 1 per 3000 deliveries, according to the European Heart Journal and the American College of Obstetricians and Gynecologists 3, 4
Pregnancy creates a hypercoagulable state due to increased coagulation factors and decreased venous flow from uterine compression, increasing the risk of pulmonary embolism, as noted by the American College of Chest Physicians 3, 4

If pulmonary embolism is suspected clinically, bilateral lower extremity compression ultrasound should be performed to look for deep vein thrombosis, as recommended by the American Journal of Respiratory and Critical Care Medicine and the European Heart Journal 3, 2
Chest X-ray and arterial blood gas (in upright position) can help risk-stratify patients with suspected pulmonary embolism, although normal results do not exclude the diagnosis, according to the European Heart Journal and the American Thoracic Society 3, 4

Patients with well-controlled mild-moderate respiratory symptoms who are asymptomatic should not restrict activity, and should be encouraged to maintain moderate-vigorous physical activity, as recommended by the American College of Sports Medicine and the American College of Obstetricians and Gynecologists 1
Patients should be instructed to seek immediate care if they develop symptoms such as chest pain, severe dyspnea at rest, palpitations or syncope, or signs of fluid overload, as advised by the American Heart Association and the American College of Cardiology 1

Maternal early warning criteria, including systolic BP >160 mmHg, diastolic BP >100 mmHg, or heart rate >130 bpm, should be evaluated immediately 5

Chest X-ray is not appropriate as first-line management when the physical examination is normal and there are no concerning features, according to the European Heart Journal 6

The American Thoracic Society/Society of Thoracic Radiology recommends performing bilateral compression ultrasound of the lower extremities first in pregnant women with suspected PE who have signs and symptoms of DVT, followed by anticoagulation if positive, to avoid radiation exposure entirely 7
Progressive dyspnea over 24 hours in pregnancy raises concern for venous thromboembolism, particularly in the context of a swollen limb, which constitutes a clear sign of possible DVT 8
Clear lungs and normal chest X-ray do not exclude PE but indicate no alternative pulmonary diagnosis, highlighting the need for further diagnostic testing 7

A positive lower extremity ultrasound warrants immediate anticoagulation treatment and makes further radiation-based testing unnecessary, as it establishes the need for treatment 7
The prevalence of DVT in pregnant women presenting with leg symptoms ranges from 7-9%, making ultrasound a high-yield initial test, especially when considering the potential risks of radiation exposure 9
PE remains the leading cause of pregnancy-related maternal death in developed countries, emphasizing the critical importance of diagnostic certainty 8

For pregnant patients with suspected PE and signs/symptoms of DVT, perform bilateral lower extremity ultrasound first; if positive, start anticoagulation, and if negative, proceed to pulmonary imaging, as recommended by the American Thoracic Society 7
If no signs/symptoms of DVT are present, perform chest X-ray, then proceed directly to pulmonary vascular imaging, with lung scintigraphy preferred over CTPA for normal chest X-ray, and CTPA preferred for abnormal chest X-ray 7

While all radiation-based diagnostic tests in pregnancy deliver doses well below the 50 mSv safety threshold for fetal harm, the risk of missing PE far outweighs radiation concerns, emphasizing the need for a balanced approach to diagnostic testing 8
The goal is diagnostic certainty while minimizing unnecessary radiation when non-radiation tests can establish treatment need, as recommended by both the American Thoracic Society and the European Heart Journal 7, 8