Pulmonary embolism - (also covered in Respiratory) Flashcards
What are potential features of pulmonary embolism?
Potential features include chest pain (typically pleuritic), dyspnoea, haemoptysis, tachycardia, and tachypnoea.
In respiratory examination, the chest will classically be clear, but real-world findings may vary.
What percentage of patients present with the textbook triad of pulmonary embolism symptoms?
Around 10% of patients present with the textbook triad of pleuritic chest pain, dyspnoea, and haemoptysis.
What did the PIOPED study in 2007 reveal about the frequency of symptoms in pulmonary embolism?
The study found the following frequencies: Tachypnea (96%), Crackles (58%), Tachycardia (44%), Fever (43%).
What does the Well’s criteria for diagnosing pulmonary embolism emphasize?
The Well’s criteria emphasize tachycardia rather than tachypnoea.
What is the typical presentation of pulmonary embolism?
Few patients (around 10%) present with the textbook triad of pleuritic chest pain, dyspnoea, and haemoptysis.
What are common clinical signs of pulmonary embolism according to the PIOPED study?
Tachypnea (96%), Crackles (58%), Tachycardia (44%), Fever (43%).
What is the significance of the Well’s criteria in diagnosing pulmonary embolism?
The Well’s criteria use tachycardia rather than tachypnoea.
What should be done for patients with symptoms suggestive of pulmonary embolism?
A history should be taken, examination performed, and a chest x-ray to exclude other pathology.
What is the purpose of the pulmonary embolism rule-out criteria (PERC)?
All criteria must be absent to have a negative PERC result, ruling out PE.
When should the PERC rule be applied?
When there is a low pre-test probability of PE (< 15%).
What does a negative PERC result indicate?
It reduces the probability of PE to < 2%.
What is the 2-level PE Wells score used for?
To assess the likelihood of pulmonary embolism.
What points are assigned for clinical signs and symptoms of DVT in the 2-level PE Wells score?
3 points for clinical signs and symptoms of DVT.
What indicates a ‘likely’ PE in the 2-level PE Wells score?
More than 4 points.
What should be done if a PE is ‘likely’?
Arrange an immediate computed tomography pulmonary angiogram (CTPA).
What should be done if a PE is ‘unlikely’?
Arrange a D-dimer test.
What is the recommended initial lung-imaging modality for non-massive PE?
CTPA is now the recommended initial lung-imaging modality.
What are the advantages of CTPA over V/Q scans?
Speed, easier to perform out-of-hours, reduced need for further imaging, and possibility of providing an alternative diagnosis.
What is the sensitivity and specificity of D-dimers?
Sensitivity is 95-98%, but specificity is poor.
What classic ECG changes are seen in pulmonary embolism?
Large S wave in lead I, large Q wave in lead III, and inverted T wave in lead III - ‘S1Q3T3’.
What is the typical finding on a chest x-ray for pulmonary embolism?
Typically normal, but possible findings include a wedge-shaped opacification.
What is the sensitivity and specificity of V/Q scans?
Sensitivity is around 75% and specificity is 97%.
What are possible causes of mismatch in V/Q scans?
Old pulmonary embolisms, AV malformations, vasculitis, previous radiotherapy.
What may be missed by CTPA?
Peripheral emboli affecting subsegmental arteries may be missed.
What are the key changes in NICE guidelines for VTE management as of 2020?
The key changes include recommending direct oral anticoagulants (DOACs) as first-line treatment for most people with VTE, using DOACs in patients with active cancer, outpatient treatment for low-risk pulmonary embolism (PE) patients, and no longer recommending routine cancer screening following a VTE diagnosis.
What is the current approach to outpatient treatment for low-risk PE patients?
Patients with a new diagnosis of PE who are deemed low-risk are increasingly managed as outpatients, supported by NICE guidance.
What tool does NICE recommend for determining suitability for outpatient treatment?
NICE recommends using a ‘validated risk stratification tool’ to determine suitability for outpatient treatment, but does not specify which tool to use.
Which score is supported by the 2018 British Society guidelines for outpatient treatment?
The Pulmonary Embolism Severity Index (PESI) score is supported for outpatient treatment.
What are the key requirements for outpatient treatment in low-risk PE patients?
Key requirements include haemodynamic stability, lack of comorbidities, and support at home.
What is the cornerstone of VTE management?
Anticoagulant therapy is the cornerstone of VTE management.
What significant change occurred in the 2020 guidelines regarding anticoagulant therapy?
The 2020 guidelines increased the use of direct oral anticoagulants (DOACs) as first-line treatment.
What should be offered first-line following a diagnosis of PE?
Apixaban or rivaroxaban (both DOACs) should be offered first-line following a diagnosis of PE.
What is the recommended approach if neither apixaban nor rivaroxaban are suitable?
If neither are suitable, use LMWH followed by dabigatran or edoxaban, or LMWH followed by a vitamin K antagonist (VKA, i.e. warfarin).
What is the recommendation for patients with active cancer regarding anticoagulant therapy?
The new guidelines recommend using a DOAC unless contraindicated.
What should be done if a patient has severe renal impairment?
In cases of severe renal impairment (e.g. < 15/min), use LMWH, unfractionated heparin, or LMWH followed by a VKA.
What is the recommended duration of anticoagulation for all patients?
All patients should have anticoagulation for at least 3 months.
How does the duration of anticoagulation differ for provoked vs unprovoked VTE?
For provoked VTE, treatment is typically stopped after 3 months (3 to 6 months for active cancer). For unprovoked VTE, treatment is typically continued for up to 3 additional months (i.e. 6 months total).
What factors determine whether to continue anticoagulation after 3 months?
The decision is based on balancing the patient’s risk of VTE recurrence and their risk of bleeding.
What score can be used to assess the risk of bleeding?
The ORBIT score can be used to help assess the risk of bleeding.
What does NICE state regarding unprovoked DVT or PE with low bleeding risk?
NICE states that the benefits of continuing anticoagulation treatment are likely to outweigh the risks in the absence of bleeding risk factors.
What is the first-line treatment for massive PE with circulatory failure?
Thrombolysis is now recommended as the first-line treatment for massive PE where there is circulatory failure.
What should be considered for patients with repeat pulmonary embolisms despite adequate anticoagulation?
Patients may be considered for inferior vena cava (IVC) filters, which prevent clots from moving to the pulmonary arteries.
PERC criteria for excluding PE in low-risk patients - if all of the above are absent, the post test probability of PE is <2%
2-level PE wells Score
suspected PE management using 2-level Wells test
Labelled CTPA showing a large saddle embolus
CTPA showing a saddle embolus
