British Thoracic Society guidelines for the management of suspected acute pulmonary embolism

Abstract

of recommendations Clinical• All patients with possible PE should have clinical probability assessed and documented.[C] • An alternative clinical explanation should always be considered at presentation and sought when PE is excluded.[C] D-dimer • Blood D-dimer assay should only be considered following assessment of clinical probability.[B] • D-dimer assay should not be performed in those with high clinical probability of PE. [B] • A negative D-dimer test reliably excludes PE in patients with low (SimpliRED, Vidas, MDA) or intermediate (Vidas, MDA) clinical probability; such patients do not require imaging for VTE.[B] • Each hospital should provide information on sensitivity and specificity of its D-dimer test.[C] Imaging • CTPA is now the recommended initial lung imaging modality for non-massive PE. [B] • Patients with a good quality negative CTPA do not require further investigation or treatment for PE.[A] • Isotope lung scanning may be considered as the initial imaging investigation providing (a) facilities are available on site, and (b) chest radiograph is normal, and (c) there is no significant symptomatic concurrent cardiopulmonary disease, and (d) standardised reporting criteria are used, and (e) a non-diagnostic result is always followed by further imaging.[B] • Where isotope lung scanning is normal, PE is reliably excluded [B] but a significant minority of high probability results are false positive.[B] • In patients with coexisting clinical DVT, leg ultrasound as the initial imaging test is often sufficient to confirm VTE.[B] • A single normal leg ultrasound should not be relied on for exclusion of subclinical DVT.[B] Massive PE • CTPA or echocardiography will reliably diagnose clinically massive PE. [B] • Thrombolysis is the first line treatment for massive PE [B] and may be instituted on clinical grounds alone if cardiac arrest is imminent [B]; a 50 mg bolus of alteplase is recommended.[C] • Invasive approaches (thrombus fragmentation and IVC filter insertion) should be considered where facilities and expertise are readily available.[C] Treatment • Thrombolysis should not be used as first line treatment in non-massive PE. [B] • Heparin should be given to patients with intermediate or high clinical probability before imaging.[C] • Unfractionated heparin (UFH) should be considered (a) as a first dose bolus, (b) in massive PE, or (c) where rapid reversal of effect may be needed.[C] • Otherwise, low molecular weight heparin (LMWH) should be considered as preferable to UFH, having equal efficacy and safety and being easier to use.[A] • Oral anticoagulation should only be commenced once VTE has been reliably confirmed.[C] • The target INR should be 2.0-3.0;when this is achieved, heparin can be discontinued.[A] • The standard duration of oral anticoagulation is: 4-6 weeks for temporary risk factors [A], 3 months for first idiopathic [A], and at least 6 months for other [C]; the risk of bleeding should be balanced with that of further VTE.[C]