Ep 203 Intermediate Risk Pulmonary Embolism Risk Stratification, Management and Algorithm

A 30-year-old woman rolls into your resuscitation bay looking very dyspneic on a non-rebreather, clammy with a heart rate of 135 bpm. She takes oral contraceptives, has had a sudden syncopal episode, and now lies in the stretcher struggling. Her blood pressure is 100/60 and she is hypothermic with a temp of 35.7°C. Her ECG and PoCUS suggest right heart strain. CTPA confirms a saddle pulmonary embolism (PE). But she’s not hypotensive… yet. So, what’s next? How do you predict which intermediate-risk patients will suddenly deteriorate? What role do biomarkers, imaging, and hemodynamics play in decision-making? Should she receive anticoagulation alone, or is thrombolysis warranted? When should you consider catheter-directed or surgical interventions? This case focuses us to think critically about risk stratification and early interventions in PE. Not all patients fit neatly into classification boxes, making clinical judgment crucial. Join Dr. Lauren Westafer, Dr. Justin Morgenstern, Dr. Bourke Tillman and Anton as they explore the key decision points, pitfalls, and lifesaving strategies for managing intermediate-risk PE in the ED... Podcast production, sound design & editing by Anton Helman; Voice editing by Braedon Paul Written Summary and blog post by Sara Brade, edited by Anton Helman April, 2025 Cite this podcast as: Helman, A. Morgenstern, J. Tillmann, B. Westafer, L. Intermediate Risk Pulmonary Embolism Risk Stratification, Management and Algorithm. Emergency Medicine Cases. Month, 2024. https://emergencymedicinecases.com/intermediate-risk-pulmonary-embolism-risk-stratification-management. Accessed April 3, 2025 Résumés EM CasesPulmonary embolism risk categories PE severity exists on a spectrum, ranging from low-risk cases to cardiac arrest. Patients who fall in the intermediate-risk category are particularly challenging because they represent a heterogenous group with varying degrees of severity and risk for clinical deterioration. The European Society of Cardiology (ESC) classifies PE severity into four categories: Low-risk patients do not require oxygen, show no signs of RV dysfunction, and have normal biomarkers. Intermediate-low risk patients have either elevated biomarkers OR RV dysfunction but not both. Intermediate-high risk patients exhibit both elevated biomarkers AND RV dysfunction. High-risk patients have prolonged hypotension (systolic BP <90 mmHg for at least 15 minutes), require pressor support, or cardiac arrest. Source: https://doi.org/10.1161/CIRCINTERVENTIONS.116.00434 Mortality for intermediate-risk PE patients has been reported as high as 15% within the first 30 days. The challenge in the ED is identifying and treating those at the highest risk of deterioration before they progress to hemodynamic instability. The pulmonary embolism death spiral: understanding how patients decompensates helps risk stratify them In cases of clinically significant high risk and intermediate high risk pulmonary embolism, the clot is thought to increase pulmonary vascular resistance, forcing the right ventricle (RV) to work harder to pump blood forward. Since the RV is not structurally designed to handle increased afterload, it begins to dilate. This dilation leads to a vicious cycle where the RV's myocardial perfusion is compromised, further reducing its contractility. As the obstruction worsens, blood return to the left ventricle (LV) is diminished, reducing cardiac output. The dilated RV also physically compresses the LV, worsening cardiac output even further. Additionally, hypoxia from pulmonary vasoconstriction exacerbates myocardial isc...