Systemic air embolism with transient ST-segment elevation after CT-guided pulmonary lesion localization: a rare case report

Systemic air embolism is a rare but potentially catastrophic complication of computed tomography-guided transthoracic lung procedures. Although most reported cases occur after lung biopsy, it may also develop after preoperative lung nodule localization. Reports describing transient neurologic deterioration with concomitant cardiac involvement after single-pass localization remain limited. We report a case of systemic air embolism after computed tomography-guided localization of a pulmonary ground-glass nodule, presenting with transient impaired consciousness, ST-segment elevation, and subsequent myocardial injury. A 25-year-old man without known systemic disease was admitted for elective resection of a persistent 9 mm ground-glass nodule in the left upper lobe. Before surgery, localization was performed in the right lateral decubitus position using a 22-gauge spinal needle and 0.15 mL methylene blue. Immediately after the procedure, he developed abrupt impairment of consciousness. Electrocardiogram showed ST-segment elevation in leads V2-V4, and aVL. Emergency non-contrast imaging of the brain, chest, and abdomen demonstrated systemic air embolism, with air in the myocardium and left kidney, together with left-sided pneumothorax. Within 10 min, he regained full consciousness but continued to report chest tightness and chest pain. A pigtail catheter was inserted into the left pleural cavity, and emergent hyperbaric oxygen therapy was initiated. Follow-up imaging showed complete resolution of the previously identified gas. Cardiac biomarkers subsequently increased, with troponin I peaking at 1,120 pg/mL 12 h after the event, then gradually declining. The patient remained neurologically intact, was discharged 4 days after the event, and had no complications at 3-month follow-up. Systemic air embolism may occur even after single-pass computed tomography-guided lung nodule localization with a fine needle and may present with transient neurologic deterioration and myocardial injury. Prompt recognition, immediate imaging, pleural decompression when indicated, and early hyperbaric oxygen therapy may be critical to preventing permanent end-organ injury.