Nondiagnostic intraoperative transesophageal echocardiography preceding CT-confirmed pulmonary embolism: A case report

Intraoperative pulmonary embolism (PE) is a rare but potentially fatal perioperative complication, particularly in lower extremity orthopedic surgery. Transesophageal echocardiography (TEE) is a principal intraoperative bedside imaging tool for evaluating suspected PE; however, its sensitivity depends on thrombus location and patient factors. We present a 32-year-old man with morbid obesity who developed hypoxia refractory to 100% fraction of inspired oxygen (FiO₂), recruitment maneuvers and increased positive end-expiratory pressure (PEEP), with presumed hypotension, during open reduction and internal fixation of a left ankle fracture. Intraoperative TEE was nondiagnostic and reported normal biventricular size and function, whereas an earlier transthoracic study had shown right ventricular dilation. Postoperative CT angiography showed an acute PE in the right main pulmonary artery extending into bilateral segmental and subsegmental arteries, with right heart strain. The patient underwent successful mechanical thrombectomy and was discharged on anticoagulation. This case highlights the limits of TEE for detecting intraoperative PE, the hazard of false reassurance from a technically limited study, and the value of indirect signs such as a widened arterial–end-tidal carbon dioxide (PaCO₂–EtCO₂) gradient and right ventricular dilation.