Air embolism through a ventriculoatrial shunt during pneumoencephalography

Pneumoencephalography is frequently used during routine evaluation of patients suspected to have intracranial lesions. In adult patients, the procedure is usually done under local anesthesia supplemented with sedation and with minimal monitoring. Many complications have been reported to occur during pneumoencephalography, including hypotension, bradycardia, arrhythmias, syncope, hypoventilation, cerebral herniation, and air embolism through dural venous channels. A case is presented which demonstrates another route of air embolization during pneumoencephalography in a patient with a patent ventriculoatrial shunt. This case points out that, for selected patients who pose special problems, an anesthesiologist should be in attendance, and the patient should be monitored extensively.