Poster 070: Breaking the Air Lock: A Case of a Severe Venous Air Embolism after Right Heart Catheterization

Background: Venous air embolism (VAE) is an uncommon complication of a right heart catheterization (RHC) with a high mortality rate if not identified and treated effectively. We present a case of a severe VAE secondary to a RHC successfully treated with venoarterial extracorporeal membrane oxygenation (VA-ECMO).

Methods: A 78-year-old female with history of progressive fibrosing interstitial lung disease presented for diagnostic RHC to investigate patient’s suspected severe pulmonary hypertension. A right internal jugular approach was conducted with 8 French sheath, and the pulmonary artery catheter (PAC) was advanced under fluoroscopic guidance. Shortly after introduction of the PAC, the patient developed chest pain and dyspnea with evidence of severe shock and complete heart block. A rapid ultrasound for shock and hypotension exam was conducted noting severe acute on chronic right ventricular failure. Patient remained extremis despite resuscitative measures including endotracheal intubation, placement and optimization transvenous pacing, and escalation of inotropes/vasopressors. Review of the pre-and post-cineangiography noted a new lucency in the right ventricular outflow tract (RVOT) concerning for a VAE. A right femoral artery PAC was placed with air aspirated from the RVOT/pulmonary artery (PA). Patient was subsequently placed on VA-ECMO with resolution of shock symptoms. Computer tomography of the chest after cannulation demonstrated residual air within the PA. The Durant’s maneuver was utilized to allow for air to be aspirated membrane lung via the 12’oclock pigtail. Patient was subsequently decannulated on VA-ECMO day 2 with excellent recovery and discharge on hospital day 7.

Outcome: A retrospective study of 11,000 RHC's estimated the incidence of VAE to be roughly 1:722 with even small volume VAEs ( < 0.5 mL/kg) being associated with obstructive shock. Risk factors which increase the risk of a VAE during RHC include hypovolemia, low central pressures, deep spontaneous respirations, and use of larger gauge catheters (>8 French). VAEs most frequently occur during catheter insertion or removal, during introduction of the devices (PAC, transvenous pacers, etc), and flushing of unprimed lines or ruptured ballons. VAEs cause obstructive shock vai mechanical obstruction of the right ventricular outflow tract and pulmonary artery which can result in acute right-sided heart failure. Other systemic complications including strokes, limb ischemia, and mesenteric ischemia are seen in the presence of intracardiac shunts. Early recognition and management of VAEs is paramount due to high mortality rates if unrecognized or untreated (50 to 80%). Management includes standard resuscitation measures, the Durant's maneuver (left lateral decubitus and Trendelenburg positioning facilitating relief of the RVOT obstruction by translocation of the air out of the heart), hyperbarics and in cases of catastrophic VAE, as seen in this case, VA-ECMO. Prompt recognition and treatment will decrease morbidity and mortality associated with VAEs.

Conclusion: This report emphasizes the importance of prompt recognition and intervention of a catastrophic VAE secondary to RHC due to the known high mortality associated with this diagnosis. Early use of VA-ECMO in severe cases such as this may decrease the mortality associated with severe VAEs.