Common complications after lumbar puncture mainly include low cranial pressure syndrome, brain herniation, and sudden aggravation of pre-existing spinal cord and spinal nerve root symptoms. Lumbar puncture, i.e. lumbar spinal puncture, is one of the most common operations in neurosurgery, which is of great significance for the diagnosis of infectious lesions in the central nervous system, spinal cord lesions, multiple nerve root lesions, etc. 1, low cranial pressure syndrome: it is mostly caused by too thick a needle, unskilled puncture technique or getting up too early after the operation, which results in the cerebrospinal fluid flowing out of the puncture hole of spinal membrane continuously. The headache will be aggravated after the patient sits up, accompanied by nausea, vomiting, vertigo, fainting, and can be reduced or relieved when the patient lies down or the head is lowered. A small number of patients may also have impaired consciousness, psychiatric symptoms, and meningeal irritation. Therefore, fine needle puncture should be used, and after the operation, go to the pillow lying down (preferably prone) 4-6h, and drink more warm water (avoid drinking strong tea, sugar water) can often help to prevent. If it has occurred, in addition to asking the patient to continue to lie down and drink plenty of warm water, but also discretionary intravenous push or drip saline, but also again lumbar puncture sheath injection of saline, or epidural injection of saline to eliminate the negative pressure of the interstitial space in order to prevent the cerebrospinal fluid to continue to leak out; 2, cerebral herniation: cerebral herniation lies in the primary intracranial pressure, when the lumbar puncture puts too much fluid too fast, can be punctured at that time or a few hours after the operation cerebral herniation, so it should be strictly attention and prevention. Therefore, careful attention should be paid to prevent it. If necessary, after rapid intravenous input of mannitol solution and other dehydrating agents, a fine needle can be used to puncture the cerebrospinal fluid slowly and several drops of cerebrospinal fluid can be gassed out for laboratory examination. If there is any misfortune, corresponding rescue measures should be taken immediately, such as intravenous injection of mannitol and hypertonic diuretic dehydrating agent, etc., and if necessary, saline can also be rapidly pushed from the ventricular puncture and discharge of fluid and from the vertebral canal; 3. Sudden aggravation of the original spinal cord and spinal nerve root symptoms: it is mostly seen in the spinal cord compression disease, due to the change of the pressure after the discharge of fluid from the lumbar puncture, which leads to a change of the pressure balance between the spinal cord, the nerve root, the cerebrospinal fluid and the lesion in the vertebral canal. Alteration of the pressure balance between the spinal cord, nerve roots, cerebrospinal fluid and the lesion. The symptoms such as radicular pain, paraplegia and urinary and faecal disorders can be aggravated, and respiratory distress and arrest can occur in high cervical spinal cord compression. If the above symptoms are not serious, saline can be injected into the spinal canal, and if the treatment is not effective, emergency consultation for surgical treatment can be arranged. Lumbar puncture should be prohibited in patients who will undergo lumbar puncture if they have the following conditions: local skin, subcutaneous or spinal infection at the puncture point, sepsis, severe spinal deformity, or severe coagulation disorders.