Abstract
Subcutaneous emphysema is not a rare complication in intensive care unit patients. Recently, ultrasound guidance for central venous puncture is becoming popular; however, the information on imaging for subcutaneous emphysema is limited. We encountered a patient complicated with severe pneumomediastinum and subsequent subcutaneous emphysema. The catheter replacement was attempted, and we examined the visuality of cervical vessels using ultrasound sonography before the intervention. Internal jugular vein itself was observed despite of subcutaneously migrated air bubble; however, the range of ultrasound image was limited, and the relationship between the vessel and the adjacent tissue was unclear.