726 - From Needle to Embolus: Systemic Air Embolism Cases, Clinical Lessons, and Preventive Insights

Learning Objectives: -Recognize the complications of percutaneous lung biopsies and their incidences.

-Understand the physiology and clinical presentation, systemic air embolism (SAE).

-Review prevention and management of SAE through case-based discussion.

Background: Percutaneous lung biopsy is a common, minimally invasive procedure that aids in the diagnosis of lung pathology. Although generally considered a safe procedure, complications are not uncommon. While these complications do not always warrant intervention, some have significant clinical implications. Complications include pneumothorax (26.2%) {Covey, Khan, Richardson, Saji, Tomiyama, Vachani, Yeow}, hemorrhage/hemoptysis (0.06-5.3%) {Richardson, Tomiyama, Vachani, Yeow}, hemothorax (0.092%) {Tomiyama}, tumor seeding (0.01-0.06%) {Tomiyama, Wu} and SAE (0.02-0.2%) {Sun, Tomiyama, Wu}.

Clinical Findings/Procedure Details: While SAE encompasses a small percentage of complications, its clinical impact can be immediate and severe, causing ischemia to the brain, heart, spinal cord or extremities {Sun}. SAE results from the introduction of air into the arterial system. During a lung biopsy, this can occur through the creation of a small fistula between an air-containing space and a pulmonary vein upon needle entry. Another mechanism for development is the laceration of a pulmonary vein with air entering the systemic system upon removal of the needle stylet, especially during deep inhalation {Chang, Fang}.

We present two cases of SAE: one in the cerebral circulation and one in the left ventricle. These cases will guide discussion on risk factors, prevention, clinical presentation, and management. Preventative measures include pre-procedural imaging review, patient positioning during biopsy, equipment selection and technique, as well as patient breathing instructions {Wang, Sun, Glodny}. Management of SAE includes positioning for air trapping in favorable locations, 100% oxygen, hyperbaric oxygen, and specialist consultation {Wu}.

Conclusion and/or Teaching Points: While rare in occurrence, the clinical impact of SAE can be catastrophic. Understanding the physiologic causes and risk factors for SAE informs preventative measures in the pre-procedural and intraprocedural settings. Timely clinical and imaging diagnosis of SAE combined with an understanding of management strategies may limit or prevent poor clinical outcomes.