What is the next best step to confirm the clinical diagnosis in a 34-year-old woman with acute onset of shortness of breath and chest pain, oxygen saturation of hypoxemia, and no past medical history, presenting with tachypnea and distress?

From the Guidelines

The next best step to confirm the clinical diagnosis in this 34-year-old woman with acute onset shortness of breath, chest pain, hypoxemia, tachypnea, and distress is to obtain a CT pulmonary angiogram (CTPA) immediately after ensuring the patient is stabilized with supplemental oxygen. This recommendation is based on the most recent and highest quality evidence available, including the study by 1, which outlines the diagnosis and evaluation of pulmonary embolism. The clinical presentation of this patient, including acute onset of symptoms, hypoxemia, and absence of past medical history, strongly suggests pulmonary embolism (PE) as a leading consideration.

Key Considerations

• The patient's symptoms, such as shortness of breath, chest pain, and tachypnea, are consistent with PE, as noted in the study by 1.
• The patient's oxygen saturation is 88% on room air, indicating hypoxemia, which is a critical finding that necessitates immediate attention and further investigation, as suggested by 1.
• While awaiting the CTPA, basic laboratory tests should be obtained, including a D-dimer, complete blood count, basic metabolic panel, troponin, and arterial blood gas, as recommended by 1.
• If CTPA is contraindicated (such as in severe renal dysfunction or pregnancy), a ventilation-perfusion (V/Q) scan would be an alternative, as mentioned in the study by 1.

Diagnostic Approach

• The CTPA is the gold standard for diagnosing PE, as stated in the study by 1.
• Echocardiography, as discussed in the study by 1, can provide indirect evidence for the diagnosis of PE, such as dilatation of right heart chambers and RV hypokinesia, but it is not the primary diagnostic tool in this scenario.
• The clinical presentation and diagnostic approach should be guided by the most recent evidence, prioritizing the patient's morbidity, mortality, and quality of life, as emphasized by the need for prompt diagnosis and treatment of PE to prevent hemodynamic compromise and increased mortality.

From the Research

Clinical Presentation and Diagnosis

The patient presents with acute onset of shortness of breath and chest pain, oxygen saturation of 88% on room air, and no past medical history. The clinical presentation suggests a possible pulmonary embolism (PE).

Diagnostic Approach

To confirm the clinical diagnosis, the next best step would be to perform a computed tomography pulmonary angiogram (CTPA) 2, 3, 4, 5. CTPA is a highly sensitive and specific test for diagnosing PE, especially in patients with intermediate to high clinical probability.

Rationale for CTPA

• CTPA can directly visualize the pulmonary arteries and detect emboli 2.
• It has a high sensitivity and specificity for diagnosing PE, especially with modern multidetector CT scanners 3.
• CTPA can also provide information on the location and extent of the embolism, which can guide treatment decisions 4.
• Artificial intelligence (AI) technology can aid in the detection and diagnosis of PE on CTPA images, improving diagnostic accuracy and efficiency 5.

Alternative Diagnostic Approaches

• If CTPA is not available or contraindicated, other diagnostic tests such as ventilation-perfusion scanning or pulmonary angiography may be considered 2, 3.
• D-dimer testing may also be used to rule out PE in patients with low clinical probability, but it has limited specificity and may not be useful in this patient with intermediate to high clinical probability 3, 4.

Key Considerations

• The patient's symptoms and clinical presentation suggest a high clinical probability of PE, making CTPA the most appropriate diagnostic test 4.
• The use of AI technology and mobile or web-based applications can facilitate the diagnostic workflow and improve communication among healthcare providers 5.