Case Presentation: A 77 y/o male with a past medical history of metastatic renal cell carcinoma to lungs, hypertension, and chronic renal disease presented to the hospital for an elective CT-guided needle biopsy of a left upper lobe lung nodule. Post biopsy he developed an acute onset of right-sided weakness, difficulty speaking, and altered mental status. On Initial Vitals he was afebrile, BP 144/64, Pulse 72, Resp 17 SpO2 95%. On the CT scan of the chest, some air was noted in the left ventricle on the last images obtained with the guiding needle still remaining in the chest wall indicative of an air embolism.He was placed in the supine position and was taken to the emergency department. He remained hemodynamically stable on a simple face mask. Laboratory results revealed H/H 13/41, Platelets 137, Potassium 5.2, and Creatinine 1.61. Chest x-ray was negative for pneumothorax. He had a CT head without contrast which showed no acute intracranial process. Also CTA head/neck showed no large vessel occlusion, aneurysm, or high-grade stenosis. The patient was unable to get an MRI of the brain due to a pacemaker. On arrival to the ICU, he was awake Oriented x 3, ill-appearing, and continues to have right upper extremity weakness. He underwent hyperbaric oxygen therapy during which he developed tonic-clonic seizure activity. He underwent urgent decompression and was intubated. The repeat CT head was negative. Further, he developed distributive shock after seizure activity, was placed on vasopressor, and treated in the ICU which later on resolved. His weakness did show some improvement and was eventually discharged to a nursing facility in stable condition.
Discussion: Lung biopsy is a very frequently done procedure and mostly is considered safe. The most frequent complication resulting from percutaneous pulmonary biopsies is pneumothorax (~35% of procedures). Severe complications such as malignant seeding, tension pneumothorax, severe alveolar hemorrhage, and air embolism occur only in less than 1% of cases. The risk of air embolism increases with underlying risk factors like COPD, longer needle path (>4 cm), subpleural lesions, smaller lesions and wider insertion angle of the needle, PEEP, coughing during the biopsy, and prone position. Air embolism is likely caused by a fistula between the pulmonary vein and the atmosphere or the airway (bronchi or alveoli) created by the biopsy needle. The most serious concern regarding air entering the arterial system is the occlusion of functional end arteries within the cardiac and cerebral circulation specifically causing mechanical obstruction, and vasospasm, which may result in severe morbidity or mortality. So far main treatment in the form of hyperbaric oxygen has been devised in the literature with variable outcomes.
Conclusions: Systemic arterial or venous air embolism is a rare but much-feared complication of percutaneous lung biopsy. It is often suboptimally managed. Some studies show good outcomes after prompt treatment using hyperbaric oxygen but don’t always work because of their own complications. A high clinical suspicion is needed in a correct scenario to identify air versus blood clots to adequately treat it to get favorable outcomes. Maximum preventive measures should be taken to decrease the chances of it and more education is needed for the first responders as well.