Which of the following is the most sensitive bedside clinical sign for acute pulmonary embolism?

Explanation

## Clinical Signs of Acute Pulmonary Embolism **Key Point:** Tachycardia (heart rate >100 bpm) is the most sensitive bedside sign of acute PE, present in 40–50% of patients with confirmed PE. However, it is NOT specific — many other conditions cause tachycardia. ### Sensitivity and Specificity of Clinical Signs | Sign | Sensitivity | Specificity | Comment | | --- | --- | --- | --- | | Tachycardia (HR >100) | 40–50% | Low | Most sensitive but non-specific | | Tachypnea (RR >20) | 30–40% | Low | Common in PE but not specific | | Pleuritic chest pain | 40–50% | Moderate | Suggests peripheral PE with infarction | | Hemoptysis | 5–15% | High | Rare; indicates pulmonary infarction | | Cyanosis | <5% | High | Uncommon; suggests massive PE | | DVT signs (leg swelling) | 25% | Moderate | Present in minority of PE cases | **High-Yield:** No single clinical sign reliably rules in or rules out PE. Diagnosis requires integration of clinical suspicion with D-dimer and imaging (CT pulmonary angiography). **Clinical Pearl:** The absence of tachycardia does NOT exclude PE — up to 50% of PE patients may have normal heart rate, especially if PE is small or chronic. ### Why Other Options Are Less Sensitive - **Pleuritic chest pain:** Present in ~40–50% but suggests peripheral/pleural involvement; absent in central PE. - **Hemoptysis:** Rare (~5–15%); indicates pulmonary infarction, which occurs only with peripheral PE and compromised bronchial circulation. - **Cyanosis:** Very rare (<5%); seen only in massive PE with severe right heart strain. [cite:Harrison 21e Ch 298]