Lower extremity arterial air embolism secondary to clostridial gas gangrene - Diagnosis by Doppler sonography

Introduction of air into the arterial system can result in air embolism. Most cases of arterial gas embolism (AGE) reported in the literature are iatrogenic, in which embolism is the result of an invasive medical procedure or surgery.(1) These include umbilical catheterization in neonates, the introduction of central venous lines, neurosurgical procedures, open heart surgery, and pulmonary barotrauma as a complication of ventilator therapy.(1) Arterial gas embolism may also be seen after diving as a result of pulmonary barotrauma or secondary to acute decompression.(1) Detection of intravascular air has been facilitated by various imaging modalities. Sonographic detection of air has been described previously.(2-4) The reports mostly focused on the cerebral arterial system because AGE may result in fatal complications at this site. There are a considerable number of reports on detection of air embolus by transcranial Doppler sonography.(3,4) Conversely, to our knowledge, sonographic detection of AGE in the lower extremity arteries has not been described. This report presents the sonographic findings of air within the lower extremity arterial system. Gas gangrene (GG) as the etiologic factor and the possible pathophysiologic mechanisms for air emboli in this situation, as well as the thrombotic complications, are discussed.