Varies. I have patients who have had their shunt for 20 years which still works. I have others whose shunt fails in just a few years. Newer technology is helping shunts last longer.
Indefinite. It seems that most children will need one or two revisions before the age of 18, but that is a very general statement. Many adults will go years without a problem. However, a shunt is a mechanical device and it should always be remembered as a potential source of trouble if a person is sick. See this monograph on hydrocephalus for more: http://wp. Me/s382os-hydrolog I recommend a medic alert tag.
Years. Shunts used to fail on a regular basis- but today's shunts are more complex and sophisticated. They can work for multiple years without fail.