The diagnosis and management of pulmonary embolism

Pulmonary embolism (PE) is a condition characterised by an obstruction of the pulmonary arterial system by one or more emboli. Advanced clinical practitioners are often faced with ruling out a diagnosis of PE in patients with non-specific symptoms such as dyspnoea and pleuritic chest pain, which can be fairly mild and therefore a diagnosis of PE easily missed. PEs can be a challenge to diagnose, especially in elderly people, since it can be difficult to differentiate their symptoms from other less serious illnesses. Widely used scoring tools are helpful to calculate a patient's probability of having a PE. The Wells score is the most widely used pre-test clinical probability indicator of PE used in the UK, which scores the patient's probability of having a PE based on their risk factors. The D-dimer test is a relatively simple investigation to rule out venous thromboembolism (VTE) but can be raised for various reasons other than PE. Computed tomography pulmonary angiography (CTPA) is regarded as the gold standard imaging modality for investigation of acute PE but ventilation-perfusion (VQ) scans can be used as an alternative imaging technique for diagnosing PE in those where CTPA is contraindicated. Thrombolysis is underused in clinical practice due to the fear of adverse bleeding events. Patients without a massive or sub-massive PE are treated with anticoagulant therapy, usually commencing with subcutaneous low-molecular-weight heparin and switching over to a direct oral anticoagulant (DOAC). There has been a shift away from treatment with warfarin for the prevention and treatment of VTE over the past decade.