So my name is up for assessment, and can fall anywhere from 1-20th January. Part of the assessment includes knowing how to perform the myriad of procedures that is part of our day-to-day work life. This will be a way for me to revise the procedures and at the same time find out whatever short comings that I may have. Note that everything here is written based on my memory, without referring to any external sources. Due to that, the accuracy of the information contained within may be questionable and downright incorrect. Should you have different views, please let me know so that I may correct accordingly.
Today we’re going to discuss Lumbar Puncture. Let’s do it systematically.
LP : Divided into Therapeutic and Diagnostic.
Therapeutic would be to reduce ICP.
Diagnostic would be to identify any CNS infections of various nature. Parasitic, Bacterial, Viral, etc. To identify malignancy in CSF. To diagnose any CNS diseases.
Contraindications: Infection at Puncture area. Coagulopathy. Vertebra Deformities (Kyphosis or Scoliosis). *Note, You can do it for Kyphosis and Scoliosis, but the risk of shit going wrong is higher, so it’s generally done by someone experienced, read: Not You.
Procedure:
1) As with all procedures, Explain the procedure to patient, and acquire consent.
2) Respect patients privacy, pull the curtains or take the patient to the procedure room.
3) Prepare all required equipment prior to starting. Sterile Gloves, Dressing Kit, Spinal Needles, Collection Bottles, Local Anaesthesia, Sober Physician.
4) Vital sign monitoring throughout the procedure, and constant reassurement to patient required.
5) Patient assumes the fetal position. Left/Right Lateral with neck flexed and knees as close to the chest as possible.
6) Procedure is done in Aseptic Technique under LA.
7) Clean the area with Povidon X2 in a circular pattern, from inside to out. Clean again with Alcohol. Try your best not to drink the alcohol.
8) Apply Drape.
9) Identify site of insertion. Between L3 and L4. Do not go below L5 as the Cauda Equina lies there. You may use the posterior superior iliac spine as landmarks.
10) Apply LA. As always when you insert the needle, aspirate first to ensure there’s no blood, and then inject the LA as you pull out. Be generous, you may finish an entire ampule.
11) Introduce Spinal Needle on insertion site. Push the needle in till you feel the first “give”. This indicates penetration of the ligamentum Flavum. Proceed till the second “give”, which indicates penetration of the dura mater. You’re now in the subarachnoid space bitches.
12) You may now opt to find the opening pressure by using a manometer. 10-18 cmH20 is usually considered normal. This relates to about 8-15 mmhg.
13) Remove the stylet, and collect drops of each fluid. You’ll need enough to send for the following investigations.
I)Indian Ink II) C+S III) Cytology IV)Biochemistry V) Gram Stain VI) FEME VII) AFB/Microbacterium
14) Once you’ve enough sample, reinsert the stylet into the needle, and withdraw the needle, apply pressure on the site.
15) Apply Gauze with Flavine and complete dressing, and tell patient to get sufficient bed rest.
16) Document procedure into Patient Ticket as retrospective entry.
Complications:
When sufficient CSF is withdrawn, patient may have nausea and headache. Sufficient bed rest can overcome these as more CSF is eventually produced. Other complications include actually damaging spinal nerves, which may cause numbness or paraplegia and epidural bleeding.
It is hard to describe, but when you’re there, you’ll know what I mean.