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 in Figure 1. 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 (Figure 1).
 
Although it is potentially fatal complication, CTTB-related SAE is rare, occurring in less than 0.1% of cases.(1-3) The pathophysiology involves two primary mechanisms(3): 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.(1)
 
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.(2) Preventive measures, such as placing the patient in a biopsy side-down position, have significantly reduced the incidence of this complication.(1) 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.(3)
 
REFERENCES
 
1.       Glodny B, Schönherr E, Freund MC, Haslauer M, Petersen J, Loizides A, et al. Measures to Prevent Air Embolism in Transthoracic Biopsy of the Lung. AJR Am J Roentgenol. 2017;208(5):W184-W191. https://doi.org/10.2214/AJR.16.16048
2.       Zhang H, Wang S, Zhong F, Liao M. Risk factors for air embolism following computed tomography-guided percutaneous transthoracic needle biopsy: a systematic review and meta-analysis. Diagn Interv Radiol. 2023;29(3):478-491. https://doi.org/10.4274/dir.2022.221187
3.       Hare SS, Gupta A, Goncalves AT, Souza CA, Matzinger F, Seely JM. Systemic arterial air embolism after percutaneous lung biopsy. Clin Radiol. 2011;66(7):589-596. https://doi.org/10.1016/j.crad.2011.03.005