Subdural hematoma after ventriculoperitoneal shunt overdrainage is one of the complications of a ventriculoperitoneal shunt (VPS) procedure, and it should be considered in any patient who presents with a malfunctioning shunt. The incidence of subdural hematoma related to over-drainage varies considerably in published reports and appears to be approximately 3 to 12% 1) 2).

see Chronic Subdural hematoma after ventriculoperitoneal shunt overdrainage

1)
Moussa AH, Sharma SK. Subdural haematoma and the malfunctioning shunt. J Neurol Neurosurg Psychiatry 1978;41(8): 759–761
2)
Sternbach GL, Sternbach MS. Subdural hematoma in a shunted patient. J Emerg Med 2005;29(4):483–484