1. Lumbar Puncture Kalpesh Patel, MD Dept. of Pediatric Emergency Medicine December 6, 2006

2. 2 Objectives  To learn the indications and contraindications for performing lumbar puncture  To learn lateral decubitus and sitting procedure for lumbar puncture  To learn the median and paramedian approach  To review complications that can occur with lumbar puncture, their precautions and treatments

3. 3 History  CSF first examined in 19 th century using primitive techniques (sharpened bird quills)  Modern technique first performed by Quincke in 1890 on a small child and has changed little since then

4. 4 Indications  To obtain CSF for the diagnosis of: Meningitis Meningoencephalitis Subarachnoid hemorrhage Malignancy – diagnosis and treatment Pseudotumor Cerebri Other neurologic syndromes

5. 5 Contraindications  Unstable patient with cardiovascular or respiratory instability  Localized skin/soft tissue infection over puncture site  Evidence of unstable bleeding disorder Platelets < 50,000 or clotting factor deficiency

6. 6 Contraindications  Increased intracranial pressure Head CT before study if focal neurologic findings present to rule out impending cerebral mass herniation Normal CT does not preclude intracranial HTN Do not delay antibiotics to obtain imaging studies when bacterial meningitis is strongly suspected  Neurologic deterioration can occur if LP is done below the level of a complete spinal subarachnoid block  Caution in patients with Chiari malformations

7. 7 Equipment  Most CSF trays come with: Anesthetic such as:  Topical - EMLA, Elamax, Zylocaine cream  Lidocaine 1% with 25 gauge needle and syringe Povidone-iodine solution & sponge wand Drapes, gauze, and bandages Manometer, stopcock and tubing in non- infant kits

8. 8 Equipment  Spinal needle, usually 22 gauge 1.5 in for < 1 yr 2.5 in for 1 year to middle childhood 3.5 in for older children and adolescents Larger for large adolescents  Atraumatic needles, less spinal headaches

9. 9 Lateral Decubitus Position  Apply topical anesthetic 30-45 min prior to procedure  Spinal cord ends at L1-L2, so sites for puncture are located at L3-L4 or L4-L5  Restrain patient in lateral decubitus position Maximally flex spine without compromising airway Keep alignment of feet, knees and hips Position head to left if right handed or vice versa

10. 10 Procedure  Cleanse skin with povidone iodine from puncture site radially out to 10 cm and ALLOW TO DRY  Drape below patient and around site with fenestrated drape  Anesthetize with lidocaine if topical not used by: Intradermally raising a wheal at needle insertion site Advance needle through wheal to desired interspace  Careful not to inject into a blood vessel or spinal canal

11. 11 Procedure  Insert spinal needle with stylet with bevel up to keep cutting edge parallel with nerve and ligament fibers

12. 12 Procedure  Aim towards umbilicus directing needle slightly cephalad  Hold needle firmly

13. 13 Procedure  A “pop” of sudden decrease in resistance indicates that ligamentum flavum and dura are punctured  Remove stylet and check for flow of spinal fluid

14. 14 Procedure  If no fluid, then: Rotate needle 90° Reinsert stylet and advance needle slowly checking frequently for CSF  Jugular vein compression can increase CSF pressure in low flow situations  If bony resistance is felt immediately then you are not in the spinal interspace  If bony resistance is felt deeply, then withdraw needle to the skin surface and redirect more cephalad and increase patient flexion  If bloody fluid that does not clear or that clots results, then withdraw needle and reattempt at a different interspace

15. 15 Manometry  When CSF flows, attach manometer to obtain opening pressure if desired  Pressure can only be accurately measured in lateral decubitus position and in the relaxed patient  Attach manometer with a 3-way stopcock when free flow of CSF is obtained  Read column when highest level is achieved and respiratory variation is noted

16. 16 Procedure  Collect 1ml of CSF in each of 3 vials for: Tube 1: culture & gram stain Tube 2: glucose, protein Tube 3: cell count & differential and extra CSF if desired for other lab tests  Check closing pressure with manometer, if desired  Reinsert stylet and remove needle in one quick motion  Cleanse back and cover puncture site

17. LP The Movie

18. 18 Sitting Position  Restrain infant in the seated position with maximal spinal flexion Hold infant’s hands between flexed legs with one hand and flex head with the other hand  Drape patient below buttocks and fenestrated drape opening over puncture site  Insert needle so bevel is parallel to spinal cord (Bevel left or right)  Cannot measure pressure accurately in this position

19. 19 Paramedian (Lateral) Approach  Use for patients who have calcifications from repeated LPs or anatomic abnormalities  Needle passes through erector spinae muscles, and ligamentum flavum Bypasses supraspinal and interspinal ligaments  Less incidence of spinal headache

20. 20 Complications  Headache Uncommon in < 10 y/o  Apnea (central or obstructive)  Back pain Occasionally with short-lived referred limp Disc herniation if needle advanced too far  Bleeding or fluid leak around spinal cord  Infection, pain, hematoma  Subarachnoid epidermal cyst  Ocular muscle palsy (transient)  Nerve Trauma  Brainstem herniation

21. 21 Spinal Headache  Most common complication  Risk factors: female, age 18-30, lower BMI, hx of HA, prior spinal HA  Bilateral HA, improves when supine  Can last hours to weeks  Supine position for at least 2 hours  Hydration  Caffeine either PO or IV  Epidural blood patch

22. 22 Spinal Headache Prevention  Can avoid by: Passing needle bevel parallel to longitudinal fibers of dura Replacing stylet before removing needle Using small diameter needles Using atraumatic needles  Bed rest or PO intake after LP does not reduce incidence of headache

23. 23 Nerve Root Trauma/Irritation  Can feel electric shocks or dysesthesias  Back pain can persist for months Consider disc herniation  Rarely permanent  Withdraw needle immediately  If pain or motor weakness persists, start corticosteroids  Electromyogram/nerve conduction velocity studies should be scheduled if pain persists

24. 24 Herniation  Manifests initially as altered mental status, followed by cranial nerve abnormalities and Cushing triad  May be rapidly fatal.  Immediately remove needle and raise the head of bed to 30-45° improve venous return from the brain.  Mannitol or 3% Saline  Intubate patient and hyperventilate  Emergent neurosurgical consult

25. 25 Epidermal Inclusion Cyst  Very rare due to use of stylet  Occurs when a core of skin is driven into spinal or paraspinal space with hollow needle  Do not remove stylet until through the skin

26. 26 Failure of Procedure  If sample of CSF is critical several alternatives are available: Have someone else try  Anesthesia  Neurology Bedside ultrasound for difficult LPs Radiographic guided procedure  Fluoroscopy  Ultrasound  CT Cisterna Magna tap

27. 27 Questions?

28. 28 Bibliography  Fleisher GR, Ludwig S, Henretig FM. Textbook of Pediatric Emergency Medicine Fifth Edition. Lippincott Williams & Wilkins 2006. p201-212.  Levin DL, Morriss FC. Essentials of Pediatric Intensive Care Second Edition. Churchill Livingstone 1997. p369-370,411-412.  Robertson J, Shilkofski N. The Harriet Lane Handbook Seventeenth Edition. Elsevier Mosby. 2005. p86-88.  King C, Henretig Fred. Pediatric Emergency Procedures. Lippincott Williams & Wilkins 2000. p 124-128.  Straus SE, Thorpe KE, Holroyd-Leduc J. How do I perform a lumbar puncture and analyze the results to diagnose bacterial meningitis? JAMA. 2006 Oct 25;296(16):2012- 22.  Peterson MA, Abele J. Bedside ultrasound for difficult lumbar puncture. J Emerg Med. 2005 Feb;28(2):197-200.  Runza M, Pietrabissa R, Mantero S. Lumbar Dura Mater Biomechanics: Experimental Characterization and Scanning Electron Microscopy Observations. Anesthesia and Analgesia. 1999;88:1317-21.  Sucholeiki R, Waldman A. Lumbar Puncture (CSF Examination). E-medicine. 2006 http://www.emedicine.com/neuro/topic557.htm. http://www.emedicine.com/neuro/topic557.htm  Walter K. Manual of Common Bedside Surgical Procedures Second Edition. Lippincott Williams & Wilkins 2000. p181-186.  Boon JM, Abrahams, PH, Meiring JH, Welch T. Lumbar Puncture: Anatomical Review of a Clinical Skill. Clinical Anatomy 2004;17:544-553  Evans RW. Special Report: Complications of Lumbar Puncture and Their Prevention with Atraumatic Lumbar Puncture Needles. Medscape 2000. http://www.medscape.com/viewarticle/420288. http://www.medscape.com/viewarticle/420288