 Good day everybody. Welcome to our next next episode of the video. This time the video is going to be slightly different. Before that my name is Dr. Sanjay Sanyal, professor and course director of neuroscience and the camera person is Mr. Mark Lesserd our IT administrator. In this video we shall demonstrate the technique the steps of lumber puncture as we do it on a scientific trainer which we have procured from the company called the Gaumard scientific with special permission. So this Gaumard scientific trainer is a mannequin a semi-hemi mannequin and it simulates exactly how it feels to do a lumber puncture on a human being. This first screenshot that you see in front of you this is showing the trainer in the so-called sitting position. The thumbs are located at the L4 spinous process and the digits are located the middle finger and the index finger are located over the highest point of the aliac crest. So this is the technique for locating the L4 spinous process which is a very important landmark in doing lumber puncture. However for the rest of the video we are going to demonstrate the lumber puncture in the lying in the left lateral position. So in this the trainer is lying as if the patient is lying in the left lateral position. This is the head end of the patient and this is the foot end of the patient. This is the back of the patient. The index finger is located over the L4 spinous process and the technique for determining the L4 spinous process is the same as I mentioned earlier. We take the highest point of the aliac crest here and the highest point of the aliac crest here and we join them by an imaginary line which is known as the supracrystal plane and that plane goes through the L4 spinous process. Once we have the L4 spinous process the space just above that is the L3 L4 space and the space just below that is the L4 L5 space. We usually choose the L3 L4 space for the lumber puncture procedure. Next step once the patient is in position we have to hyper flex the spine that is done by flexing the neck of the patient so that the chin touches the chest and the knees touch the abdomen of the patient. That way the spinous processes the inter spinous processes the space between them open up. We clean the area with antiseptics solution. We can use either poverty on iodine 0.5 percent or 10 percent which is known as betadine or we can use isopropyl alcohol or we can use ethyl alcohol or we can use chlorhexidine gluconate or we can use various combinations of them. However in this particular trainer we do not use poverty on iodine betadine because it will stain the trainer. So this is just to show you that antiseptic preparation is important. The next step in the process is to give a sterile drape covering so that we do not touch any on sterile areas. The sterile drape has got either a square or a central circular opening which is centered over the side of the lumbar puncture. The next step, local anesthesia is infiltrated as if we are doing it on a patient. The local anesthetic agent which is usually used is lignocaine 0.5 or 1 percent and it is infiltrated in the subcutaneous plane just so that the patient will not feel the pain of the lumbar puncture needle. The next step is to assemble the manometry assembly. You can see this is the burette the vertical tube which will be used to record the lumbar pressure and this is the three-way stopcock which will be connected to the lumbar puncture needle. So this is just to assemble it and keep it ready so that when we can do the lumbar puncture pressure recording at the appropriate moment. Now comes the actual step. This needle that you see in front of you is the is a 20 gauge 2-heat needle. It's called the lumbar puncture 2-heat needle and it is of sufficient length to penetrate right up to the lumbar cistern which is the space which is used to drain the CSF. This is the 2-heat needle. This needle is a hollow needle and it contains a stillet which is attached to this yellow hub that you see here. The lumbar puncture needle is inserted usually through the L3L4 spinous process space, interspinous space and the tip of the needle is directed slightly towards the as if it's being directed towards the umbilicus of the patient. It should be absolutely horizontal and it should be at right angles to the surface of the skin. The needle is gradually advanced. The layers that it pierces through are one skin, subcutaneous tissue, supraspinous ligament, interspinous ligament, ligament of fl... supraspinous ligament, interspinous ligament, ligament of flavum, extradural space of the spinal canal, then it pierces through the dura arachnoid membrane. Once it pierces through the dura arachnoid membrane, typically we will feel and hear a pop sensation. That is the indication that we have gone and entered the lumbar cistern. Periodically we would remove the stillet out to see the CSF dripping out. And that is what we see in this next slide here. We can see the CSF is dripping out, the simulated CSF in this particular case. In actual situation how do we determine if the CSF does not drip out? There are certain maneuvers that we can do. One maneuver is we can ask the patient to cough gently. That can sometimes bring the CSF out. The second maneuver that we can do is we can take this, hold this hub of the needle here and we can gently rotate it along its own axis without moving it forward or backwards. That way sometimes a small filament of alachnoid trabeculae which is blocking the stillet which is blocking the needle will be removed and CSF will start dripping out. So once we see the CSF dripping out, our next step will be to connect the lumbar manumetry assembly which we had assembled earlier. If you notice this is the vertical limb of the burette which will record the pressure of the 3-way stopcock. This end is connected to the hub of the lumbar puncture needle and this 3-way stopcock is turned up so that the CSF pressure can be recorded along this. The normal CSF pressure in a normal person is 60 to 150 millimeters of water in the lateral filament position. That is the usual way of recording the spinal manumetry pressure. Always remember that in a normal person there will be slight fluctuations of the CSF pressure based on respiration and the spinal arterial pulsations. Once we have recorded the CSF pressure, the next step will be to, once we have recorded the CSF pressure and as you can see in this here the next step will be to remove the manometer and turn this 3-way stopcock and put a test tube under the lumbar puncture needle so that we can have a few drops of CSF in the test tube for various analysis purpose. So these are the steps of lumbar puncture procedure and after we have achieved all these steps, the final step will be to reinsert back the stillet into the lumbar puncture needle and then pull out the needle straight backwards and using the other hand with a gauze held on it, press on the skin to give a counter pressure otherwise the skin will tent up. Once we have achieved this, then we put a steroid dressing here using a tincture benzoin seal and we close the procedure. So ladies and gentlemen, these are the steps of the lumbar puncture procedure. On principle it is very simple, however in actual practice it requires a lot of practice and it can be potentially dangerous also so we have to take precautions about doing all these things. Special thanks is for being acknowledged to GOMART Scientific. Their trainer is being used in our institution for quite some time and it has given us wonderful service and we are sending special thanks to its Vice President John Eggard for giving us explicit written permission to use the pictures in this presentation. Have a nice day. Anybody if you have got any comments or questions you can put it in the comment section below.