1. Lumber Puncture

2. Step 1: Body position 1.The patient is placed in a lateral recumbent position, the back as near the edge of the bed as possible. 2.The legs are flexed on the thighs, the thighs are flexed on the abdomen, and the head and shoulders are bent down, curving the spine convexly to afford the greatest space between the vertebrae.

3. Step 2: Puncture site 1.The interspace of the third and fourth lumbar vertebrae is selected. 2.The intersection of 2 lines, one is the middle line of the back and the other is the line connecting bilateral posterior iliac crest, can be selected to be the puncture site.

4. Step 3: Sterilizing and anaesthesia 1.The skin over the interspace of the third and fourth lumbar vertebrae is cleaned and sterilized. 2.The operator puts on sterile rubber gloves. 3.A fenestrated sterile drape is placed over the back, the window over the puncture site. 4.Local anaesthesia with Lidocaine

5. Step 4: Puncture 1.The needle is inserted through the interspace to the subarachnoid space (about 4-6 cm deep from skin), and the stylet is withdrawn. 2.If the needle is in the proper place, clear, straw- colored CSF will begin to drip out through the needle. 3.The pressure of the CSF may be measured with a manometer and sent to the laboratory for chemical or bacteriologic analysis.

6. Step 5: After Puncture 1.Withdrawing the needle after inserting the stylet and covering the puncture site with sterile gauze block. 2.The patient is usually kept flat in bed without pillow for 4-6 hours after the procedure.

7. Diagnostic Indications 1.Measuring of CSF pressure; 2.Obtaining CSF for laboratory analysis; 3.Injecting oxygen or a radiopaque substance for radiographic visualization of the spine and brain.

8. Therapeutic indications 1.Removing blood or pus from the subarachnoid space; 2.Injecting drugs; 3.Withdrawing CSF to reduce intracranial pressure; 4.Introducing a local anesthetic to induce spinal anesthesia.

9. contraindication If intracranial tumor is suspected or there is evidence of greatly increased intracranial pressure, or there is sign of herniation of brain If there are signs of infection at the site of puncture If there is evident hemorrhage tendency

10. Complications Intracranial hypotension syndrome: headache, nausea, vomiting, or signs of meningeal irritation, caused by leakage of CSF Brain hernia Nerve root hurts Others: infection, hemorrhage

11. Wish you success !