SESSION TYPE: Cardiovascular Student/Resident Case Report Posters I
PRESENTED ON: Tuesday, October 23, 2012 at 01:30 PM - 02:30 PM
INTRODUCTION: Systemic air embolism has been estimated to have an incidence of 0.02 to 0.07%, though it now seems that it might be more common than this number, mostly because of under-diagnosis secondary to asymptomatic cases incidentally found on follow up imaging studies. Venous versus arterial or right versus left sided air embolization depends on the site of infiltration of air and the presence of an intra cardiac shunt allowing the passage of air from the venous circulation to the arterial side, which may result in more catastrophic events. Hyperbaric oxygen therapy remains the mainstay of therapy with best results if received within 5 hours. Supportive measures are imperative.
CASE PRESENTATION: A 48 year old Caucasian male, underwent a CT guided biopsy of a lung nodule on the left side. Patient tolerated procedure well without any hemodynamic compromise, but was noted to have some air in the left ventricle on immediate post procedural CT scans. Cardiology and Hyperbaric Medicine were emergently consulted and patient taken for hyperbaric oxygen therapy immediately. He was treated for 90 minutes under 2.4 atmospheres of pressure and post hyperbaric oxygen therapy CT scan showed resolution of the left ventricular air seen earlier. No intra-atrial shunt was found on echocardiography. It was assessed that the patient most likely had this systemic air embolism from infiltration of a pulmonary vein during the procedure with passage of air to the left side of the heart, not requiring an intra-cardiac shunt from right to left.However, arterio-venous shunts in the lungs cannot be ruled out. Patient continued to do well without any further complications. Pathology of the biopsy specimen showed Carcinoid tumor.
DISCUSSION: Symptomatology of air embolism ranges from absence of symptoms to significant hemodynamic compromise. Dyspnea, tachycardia, chest pain, hypotension, bradycardia, and hypoxemia and if catastrophic, death may be seen. A “mill- wheel murmur” has been described as a sucking/splashing sound on auscultation from the presence of air in the cardiac chambers and great vessels. Three major mechanisms of introduction of air into the pulmonary venous bed during percutaneous biopsy are suggested- direct introduction through the needle when the stylet is removed, introduction of air into pulmonary arterial system followed by transgression into the venous system, and lastly, by formation of a fistula between an alveolar space and a vessel. Preventive measures recommended include avoiding biopsy of a cystic lesion, use of a stylet at all times, avoid coughing and straining during procedure, and using the shortest route to the lesion to minimize the amount of lung parenchyma transverse to get to the lesion.
CONCLUSIONS: As above
1) Air Embolism and Needle Track Implantation Complicating CT-Guided Percutaneous Thoracic Biopsy: Single Institution Experience. Ibukuro, Et.al. American Journal of Radiology. 2009.
DISCLOSURE: The following authors have nothing to disclose: Pratik Dalal, Divyashree Varma
No Product/Research Disclosure InformationSUNY-Upstate Medical University, Syracuse, NY