Retrograde Cerebral Venous Gas Embolism: Could it be Possible?

Air embolism is well-known but uncommon and cerebral venous gas embolism (CVGE) is even more so because it goes unnoticed in an anaesthetized patient, especially where slow entrainment of small amounts of air takes place over a period of time. A young American Society of Anesthesiologists (ASA) status I patient underwent a lumbar spine surgery and presented in the post anaesthesia care unit (PACU) with seizures. Common causes of generalised tonic clonic seizures were ruled out and cerebral hypoperfusion as a result of retrograde CVGE was the retrospective diagnosis of exclusion. The patient developed retrograde CVGE in the absence of any intracardiac septal defect or patent foramen ovale. The prone positioning along with the anatomy of the valveless vertebral plexus of veins plays an important role in the development of retrograde CVGE. A high index of suspicion and awareness is warranted from anaesthesiologists so as not to delay diagnosis and treatment of this rare entity.