I had a spitz-holter shunt inserted for acquired hydrocephalus following a ruptured cerebral aneurysm in 1970 at age 16 and after a craniotomy to clip the same and to remove a large AVM. This has been revised numerous times. I am currently living in Spain, and am a bit nervous of going into a Spanish hospital should the shunt block. I think I would prefer go back to the UK for a revision. Does anyone know if it is dangerous to fly at 33-35000 feet with a malfunctioning shunt?