Pulmonary embolism: recognition, risk stratification and anticoagulation

Manage now— do this, in order

• Oxygen first to saturations of 94–98% (88–92% if at risk of hypercapnic respiratory failure); in the shocked patient begin high and titrate down.
• Anticoagulate before the scan when PE is likely — never let a test delay the first dose. Screen first for bleeding risk (active bleeding, recent GI bleed, recent stroke, recent major surgery, head injury, uncontrolled severe hypertension, platelets, INR/APTT, renal function) and measure the weight — never estimate it.Doctor / Nurse
• Enoxaparin 1 mg/kg subcutaneously every 12 hours (actual body weight) or 1.5 mg/kg once daily; twice-daily preferred in the sicker patient and obesity; creatinine clearance < 30 mL/min: 1 mg/kg once daily. Children: 1.5 mg/kg 12-hourly under 2 months, 1 mg/kg 12-hourly from 2 months.Doctor / Nurse
• Use unfractionated heparin instead when haemodynamically unstable, when thrombolysis is being considered, in creatinine clearance < 30 mL/min or at extremes of weight: 80 units/kg IV bolus, then 18 units/kg/hour titrated to an APTT ratio of 1.5–2.5 times control — first APTT at 6 hours and after every rate change.Doctor / NurseNot available at your setup — Infusion pump, Coagulation (PT/INR).
• Fluids in small measured boluses only: 250–500 mL 0.9% sodium chloride over 15 minutes (children 10 mL/kg), reassessing after each — if pressure does not improve or the JVP rises, stop and start noradrenaline 0.05 microgram/kg/minute titrated to MAP ≥ 65 mmHg. Never fill the distended right ventricle with a fixed litre.Doctor / Nurse
• Thrombolyse acute massive PE with haemodynamic instability: alteplase 100 mg IV over 2 hours (10 mg over 1–2 minutes then 90 mg over 2 hours); in cardiac arrest or peri-arrest 0.6 mg/kg over 15 minutes to a maximum of 50 mg, and continue CPR for at least 60–90 minutes. Withhold the heparin infusion during alteplase; restart without a bolus once APTT falls below twice control. Thrombolysis carries a 2% risk of intracranial haemorrhage.Doctor / Nurse
• Continuation — pick ONE strategy and write it down: (1) parenteral drug overlapped with warfarin 5 mg once daily to INR 2.0–3.0, continuing the parenteral agent at least 5 days and until two in-range INRs a day apart — never stop the heparin the day warfarin starts; (2) LMWH for 5 days then dabigatran 150 mg twice daily or edoxaban 60 mg once daily; (3) rivaroxaban 15 mg twice daily for 21 days then 20 mg once daily with food, or apixaban 10 mg twice daily for 7 days then 5 mg twice daily — the higher initial dose is not optional. Minimum 3 months in every patient; in pregnancy LMWH throughout.Doctor / Nurse
• Where CT is unavailable and the patient is shocked: bedside echocardiography showing right ventricular dilatation in a shocked, hypoxaemic patient with clear lungs and a compatible history is sufficient grounds to treat for PE; where no imaging is achievable in a dying patient, make the diagnosis clinically and document the reasoning — absence of imaging is not a reason to withhold treatment.Not available at your setup — Ultrasound. No echo either: diagnose clinically in the dying patient and treat — document the reasoning.
• If intubation is unavoidable it is uniquely hazardous: induction agents drop the pressure and positive-pressure ventilation cuts venous return — an experienced operator, vasopressor support already running, low tidal volumes and the lowest airway pressures that ventilate.Doctor / NurseNot available at your setup — Endotracheal intubation kit.