Objective:To explore the curative effect of lumbar cistern drainage under the intracranial pressure monitoring on severe traumatic brain injury of after decompressive craniectomy. Methods:Totally 123 patients with severe traumatic brain injury were randomly divided into two groups:73 cases of patients with lumbar cistern drainage under the intracranial pressure monitoring as a treat-ment group and 50 cases of patients with lumbar cistern drainage as a control group. Cerebrospinal fluid flow

mannitol application

the incidence of complications and six months glasgow outcome score of two groups were compared through the observation.Results:The dosage（428.01±111.85）g and time（4.52±1.54）d of mannitol in the treatment group were significantly lower than those in the control group（794.00±179.32）g and（8.36±2.06）d

with statistically significant differences between the two groups（t =13.940

P=0.000;t=11.840

P=0.000）. Cerebrospinal fluid drainage in the treatment group（1 180.40±174.63）m L was lower than that in the control group（1 663.58±213.61）m L

with statistically significant differences（t=13.750

P=0.000）. The incidence of complications（cerebral hernia

secondary hemorrhage

electrolyte disturbance

acute kidney injury）in the treatment group was lower than that in the control group

with statistically significant differences（P<0.05）. In the treatment group

the recovery rate of the prognosis in Glasgow（good recovery + mild disability）was 63%

and the recovery rate of the control group was 44%

with statistically significant differences（χ2=4.340

P=0.040）. Conclusion:The curative effect of lumbar cistern drainage under the intracranial pressure monitoring on severe traumatic brain injury of after decompressive craniectomy is better than that of simple line of the lumbar cistern drainage.