Case 16: Sudden chest pain
Tuesday, April 19th, 2011Author: Dr Roshini Kulanthaivelu
A 66 year lady who had flown to the UK from Nigeria where she had recently undergone chemotherapy for breast cancer, presented to the ED with sudden onset pleuritic chest pain, SOB and haemoptysis.
Her observations were BP 101/84, HR 117, pO2 98% RA, RR 28, T 38.0oc. On examination, chest pain was reproducible on palpation and crackles with reduced air entry were found over the left base.
ABG showed a pO2 of 10.5, pCO2 3.7, pH 7.48 BE -2.0, HCO3 20.9, Lactate 2.4.
1. What is the most likely diagnosis?
Click to see the answerPulmonary Embolism (PE).
This is a thromboembolic event which results in occlusion of the pulmonary artery or one of its branches. It shares the same pathophysiology as that of Deep Vein Thrombosis (DVT) and is usually as a consequence of it, with 70% of PEs having an associated DVT on diagnostic imaging. It is a common cardiovascular emergency as it can often cause RV failure, haemodynamic disturbance and even result in cardiac arrest, yet the clinical presentation is often very non-specific (SOB/Pleuritic chest pain/haemoptysis/syncope) and can mimic other cardiovascular conditions. For this reason stratification of PE risk is important and can easily be performed via the Well’s or Geneva score.
Below is a list of common PE risk factors:
• Surgery – Orthopaedic or abdominal/pelvic surgery
• Pregnancy – late or puerperium
• Malignancy
• Immobility – hospitalisation/institutional care/long distance flights.
• Previous DVT or PE
• Oestrogen therapy.
• Thrombotic disorders
This patient was at high risk of PE due to the history of ongoing breast cancer with recent chemotherapy, recent flight, tachypnoea, tachycardia, haemoptysis, temperature and sudden onset pleuritic chest pain. Although it may seem some of the clinical signs are misleading, upto 20% of patients with PE do not demonstrate a hypoxia on ABG and pulmonary ischaemia can lead to reproducible chest pain on palpation.
2. How would you treat this patient?
Click to see the answerGuidelines suggest that all patients at intermediate or high risk of PE without haemodynamic compromise should be started on heparin (low molecular weight heparin (lmwh) unless contrainidicated) until diagnostic imaging can take place (CTPA/Pulmonary angiography).
Patients with haemodynamic disturbace i.e. persistent hypotension despite treatment, cardiogenic shock or cardiac arrest, should be treated with thrombolysis or surgical/percutaneous embolectomy.
In this particular patient, as the diagnosis of sepsis has not been excluded they should be treated with both heparin and broad spectrum antibiotics.
3. What are the contraindications to standard treatment?
Click to see the answerTreatment with heparin is contraindicated in those patients with thrombocytopaenia (including a history of Heparin induced thrombocytopaenia), bleeding diatheses or a recent bleed. Low molecular weight heparin specifically, is contraindicated in those patients with an eGFR<30.
This lady’s FBC showed WCC 0.2 Neu 0.02 Hb 9.2, MCV 90, PLT 48.
Heparin; neither unfractionated or lmwh could safely be initiated in this patient due to the high risk of bleeding, therefore only broad spectrum antibiotics, as per neutropaenic sepsis protocol were administered initially.
4. What would be your next management step in this case?
Click to see the answerDiscuss with haematology & perform diagnostic imaging.
In all patients with neutropaenia and thrombocytopaenia it is necessary to liase with haematologists early in management. Diagnostic imaging was recommended in this case to confirm the presence of a PE and determine the need for anticoagulation in light of the high bleeding risk. The patient was then given both GCSF and Platelet transfusion to boost White Cell Count and platelets. CTPA confirmed large arterial thromboembolism with distal infarction and the patient subsequently received unfractionated heparin before receiving lmwh in the long term.