Bypass is a classic method of treating hydrocephalus, and surgical complications occur at a relatively high rate in the management of neurosurgical disorders. What are the risks or sequelae of hydrocephalus drainage? In neurosurgical guidelines, the sequelae of hydrocephalus shunt are mainly shunt infection, shunt obstruction, shunt fracture, intracranial or intra-abdominal shunt ectopic, cerebrospinal fluid overdrainage cerebrospinal fluid underdrainage, intracranial hemorrhage, epilepsy, etc., as follows: 1. Infection: The common postoperative ones are intracranial infection, incisional infection, intra-abdominal infection, shunt subcutaneous channel infection, etc. Once there is infection, the shunt should be removed first, then anti-infection treatment should be given, and after the infection is effectively controlled, the surgery should be redone. 2. Excessive drainage: It can be manifested as cleft ventricle syndrome, subdural effusion or subdural hematoma. While treating the effusion or hematoma, the shunt pump with a high level of pressure should be replaced (pressure fixed shunt) or the pressure should be adjusted upward (adjustable pressure shunt). 3. Insufficient drainage: The patient’s clinical performance does not improve significantly and the ventricle does not shrink. Firstly, test whether the shunt system is clear, if obstruction is found, the shunt should be replaced. If the shunt is open, the set pressure should be adjusted down (adjustable pressure shunt) or replaced with a shunt pump with a lower level of pressure (fixed pressure shunt). Long-term bed rest can cause insufficient drainage, the patient should be encouraged to semi-sitting or standing activities. 4, shunt obstruction: the common obstruction site and cause is the intracranial shunt is poorly positioned, the general method to determine the shunt obstruction is to press the subscalp shunt pump reservoir bursa, can quickly rebound means the shunt is open, can not rebound or rebound slowly means the shunt ventricular end obstruction. It is more difficult to determine the obstruction of the ventricular end of the shunt, so we can do abdominal ultrasound to determine whether there is an intra-abdominal mass, and the presence of a mass indicates that the large omentum is wrapped around the shunt. Treatment: do shunt adjustment or replace the shunt. 5, shunt fracture: common fracture site: shunt and pump connection and subcutaneous walking area. The site of shunt fracture can be determined by touching by hand and performing X-ray examination. As mentioned above, there are many complications after shunt surgery, so patients need to be careful when choosing the procedure. With the advent and widespread use of specialized cerebrospinal fluid techniques in recent years, successful treatment of hydrocephalus has been achieved and the probability of complications has been greatly reduced.