In this case report, argon plasma coagulation (APC) was applied in a male individual to treat an occluding tumour of the right middle lobe bronchus with a post-stenotic atelectasis. During attempted recanalisation, the patient suffered a cerebral gas embolism as seen on CT scan, resulting in a distinct neurological deficit. We discuss the available data about cerebral gas embolism as a complication of APC and possibilities to avoid such complications.