From the Guidelines
The initial workup for a patient with new onset pulmonary embolism (PE) should include prompt institution of anticoagulation therapy as soon as possible, while the diagnostic workup is ongoing, unless the patient is bleeding or has absolute contraindications, as recommended by the 2019 ESC Guidelines 1. The diagnostic approach should involve the use of recommended, validated diagnostic algorithms for PE, including standardized assessment of (pre-test) clinical probability and D-dimer testing 1. Key steps in the initial management include:
- Instituting anticoagulation therapy as soon as possible, unless contraindicated 1
- Using bedside transthoracic echocardiography in patients with haemodynamic instability to differentiate suspected high-risk PE from other acute life-threatening situations 1
- Confirming the diagnosis of PE and then further assessing the risk involving clinical findings, comorbidity, evaluation of the size and/or function of the RV, and laboratory biomarkers if appropriate 1
- Considering the best reperfusion option for patients with high-risk PE, including systemic thrombolysis, surgical embolectomy, or catheter-directed treatment 1 The choice of anticoagulant should preferentially be a non-vitamin K antagonist oral anticoagulant (NOAC) over the low molecular weight heparin (LMWH)–vitamin K antagonist (VKA) regimen, unless there are contraindications to NOACs 1. It is essential to remember that the management of PE is not limited to the acute phase but also involves long-term considerations, including the risk of recurrent venous thromboembolism (VTE) and the potential need for extended anticoagulation therapy 1.
From the FDA Drug Label
In a randomized, open-label, clinical trial in patients with a confirmed diagnosis of acute symptomatic PE, with or without DVT, fondaparinux sodium 5 mg (body weight <50 kg), 7.5 mg (body weight 50 to 100 kg), or 10 mg (body weight >100 kg) SC once daily (fondaparinux sodium treatment regimen) was compared to heparin intravenous bolus (5,000 USP units) followed by a continuous intravenous infusion adjusted to maintain 1.5 to 2.5 times aPTT control value.
The initial work for a patient with new onset Pulmonary Embolism (PE) is to start treatment with either fondaparinux sodium or heparin, with the following dosing regimens:
- Fondaparinux sodium: 5 mg (body weight <50 kg), 7.5 mg (body weight 50 to 100 kg), or 10 mg (body weight >100 kg) subcutaneously once daily
- Heparin: intravenous bolus (5,000 USP units) followed by a continuous intravenous infusion adjusted to maintain 1.5 to 2.5 times aPTT control value 2
From the Research
Initial Work for a Patient with New Onset Pulmonary Embolism (PE)
The initial work for a patient with new onset PE involves several steps to diagnose and manage the condition effectively.
- The first step is to use a clinical probability assessment tool, such as the Wells score, to determine the patient's likelihood of having a PE 3.
- If the clinical probability is low, a D-dimer test can be used to rule out venous thromboembolism (VTE) 3.
- However, if the clinical probability is high or the D-dimer test is positive, imaging tests are necessary to confirm the diagnosis.
- The gold standard imaging modality for diagnosing acute PE is computed tomography pulmonary angiography (CTPA) 4, 5, 6, 3.
- CTPA has a high sensitivity and specificity for diagnosing PE and can provide accurate results quickly 6.
- Alternative imaging techniques, such as ventilation-perfusion (VQ) scans, can be used in patients where CTPA is contraindicated 5, 3.
- Other imaging modalities, such as magnetic resonance angiography (MRA) and magnetic resonance direct thrombus imaging (MRDTI), are also available but are not as widely used as CTPA 4.
- Echocardiography can be used for risk stratification of patients with PE 5.
- Reducing the scan range in CTPA can decrease radiation dose while maintaining diagnostic accuracy for detecting PE 7.