Can't say anything about cost (in a different region and go to a pediatric hospital) but the stay depends - most of our child's revisions have been one or two night stays - generally less than the time we've spent in hospital getting fluids/recovery because over draining makes my child very sick. We've never had other complications or infections with a revision (well, we've had revisions within two months of each other but the surgery recovery was not a problem, changing to a different shunt system helped). Have you had a revision before? Are you generally well at this time, do you have other factors that might complicate things, is this a new surgeon for you? The surgeon's office should be able to give you an idea on the shortest expected stay if all goes well. Call the hospital to give you an idea on the expected costs if there are no complications - or the insurance company should have some max expected patient costs.