Bubbles in my heart: systemic air embolism after CT-guided transthoracic biopsy of a pulmonary nodule

A 70-year-old male former smoker with a history of hypertension was admitted for elective CT-guided transthoracic biopsy (CTTB) of a suspicious pulmonary nodule. He was asymptomatic, and the physical examination was unremarkable. Unenhanced CT images from the periprocedural period are shown. The patient was diagnosed with a systemic air embolism (SAE), after which he was placed in the Trendelenburg position and received oxygen therapy for 3 days, being discharged without complications. Although it is potentially fatal complication, CTTB-related SAE is rare, occurring in less than 0.1% of cases. The pathophysiology involves two primary mechanisms: the entry of air into the pulmonary vein through the biopsy needle when atmospheric pressure exceeds pulmonary venous pressure; and the formation of a bronchovenous fistula. These events can lead to catastrophic outcomes such as myocardial infarction and stroke. Risk factors for SAE include a lesion being located in a lower lung lobe, a pulmonary nodule with a subsolid composition, pneumothorax, hemorrhage, and a lesion being located above the level of the left atrium. Preventive measures, such as placing the patient in a biopsy side-down position, have significantly reduced the incidence of this complication. Immediate postprocedural management involves administering oxygen to achieve an SpO₂ near 100%, placing the patient in the Trendelenburg position, and applying hyperbaric oxygen therapy if available. (author)