Triage Patients with Suspected Pulmonary Embolism in the Emergency Department Using a Portable Ultrasound Device

Abstract

The diagnosis of pulmonary embolism (PE) is difficult, despite validated diagnostic models. We sought to determine the value of a portable ultrasound device for triage of patients with suspected PE referred to the emergency department, using simplified echo criteria. We prospectively studied 103 consecutive patients with suspected PE, referred to our emergency department. After D-dimer screening, 76 patients were prospectively enrolled in this ultrasound study and underwent helical chest tomography, transthoracic echocardiography, and venous ultrasonography. Among patients with PE (n = 31), a right ventricular dilation was detected in 17 patients (55%), a direct visualization of clot in the lower limbs was present in 18 patients (58%), and 8 patients (26%) had both right ventricular dilation and deep venous thrombosis. The sensitivity and specificity of a combined ultrasound strategy using echocardiography and venous ultrasonography were respectively 87% (95% confidence interval 74% to 96%), and 69% (95% confidence interval 53% to 82%). The sensitivity of this combined strategy was significantly improved as compared to venous ultrasonography alone (P = 0.01) or echocardiography alone (P = 0.005). In patients with dyspnea or with high clinical probability of PE, this combined strategy was particularly relevant with high sensitivities (respectively 94% and 100%). Echocardiography combined with venous ultrasonography using a portable ultrasound device is a reliable method for screening patients with suspected PE referred to an emergency department, especially in patients with dyspnea or with high clinical probability.