Shawn Dowling, PGY-2 Resident Oral Rounds

1. Doctor, You made my headache worse!!! Shawn Dowling, PGY-2 Resident Oral Rounds

2. Case • 27F. Worse HA of her life. Reached maximal intensity with 2 minutes. Previously healthy. No Meds. No Family Hx of medical problems. • You want to r/o SAH. • CT head N. LP results are normal. • Two days later, pt returns with a severe bilateral frontal HA, worse with standing, relieved with lying. • Afebrile, no neck Sx, no other neuro Sx. • What is your most likely diagnosis?

3. Post-Lumbar Puncture HA’s • Epidemiology • Pathophysiology/Anatomy • Prevention Strategies • Management Strategies • Approach to the Difficult LP Likely will not have time to cover

4. History • First spinal anesthesia was in 1875 • Accidental injection of cocaine into dural space • In 1891, Quincke aspirated CSF from subarachnoid space to Tx  ICP • In 1895, Corning gave the first spinal anesthesia to Tx habitual masturbation • PLPHA were described from the first LP and 1st published case series was in 1899

5. The Lumbar Puncture • Wide number of indications in Medicine • LP’s are a frequently performed procedure in the ED • Primary indication in the ED is to look for evidence of • CSF infection • Subarachnoid hemorrhage

6. IMMEDIATE Traumatic tap Cerebral herniation Back Pain DELAYED Epidermoid tumors – historical Infection PLPHA Subdural hematoma Spinal Epidural Hematoma LP Complications

7. How often do they occur? • IR of PLPHA variable 1- 70% (Evans) • 32% for Dx LP’s w/o precautions (20G Q) • 6.1% in those who received special precautions • ED setting(Seupal 2003) • 37% with 20G Cutting • 6% with 22G Cutting

8. Why should we be concerned about PLPHA? • Of those pts that developed PLPHA most were severe • 60% were severe and 40% were moderate (Strupp) • 25% persist over 1 wk without Tx • Resulting in significant numbers of hospital re-admissions, sick days and overall morbidity • The procedures can carry potential for significant morbidity • In ED setting 33% of those w/PLPHA required EBP(Seupaul 2005) • Low but present risk of SDH (Samdani)

9. Patient Risk Factors • Young age (20-40 yrs) • Female (2x of males) • Pre-LP headache* • ?Pregnancy • *Many of the studies excluded pts with pre-LP HA’s

10. Postural HA - worsened w/i minutes of standing and relieved by lying down- in the setting of a dural puncture Characteristic location Frontal/occiptal Typical onset w/i 1-3 days(90%) and usually resolve by 2 wks w/o interventions Associated Sx: N,V, anorexia, photophobia, tinnitus Neck/upper shoulders Severe cases can have Diplopia Cranial nerve dysfx What is a PLPHA? Need to consider other Dx !!!

11. Pathophysiology • PLPHA are thought to arise from a persistent CSF leak leading to a relative intra-thecal hypovolemia • Two theories as to what causes the pain both related to brain sagging & downward shift • Causes stretch of pain sensitive structures • Cerebral vessels vasodilate to compensate for the relative hypovolemia and thus cause Sx

12. Schematic of PLPHA Pathophysiology

13. Not all PLPHA are created equal • LP’s are done for a number of indications • Diagnostic (i.e. us, neurology, radiology) • Therapeutic (i.e. spinal anesthesia, chemo, etc) • Therefore populations are very heterogenous and IR, severity & duration are VERY DIFFERENT • Thus in reviewing the literature it is crucial to know the baseline patient data and clinical scenario/indication • Unless otherwise stated these articles will be diagnostic tests (usually by neurology)

14. PROVEN Needle size Needle type  Re-inserting stylet Bevel orientation UNPROVEN* Bed rest (Thoennissen) Hydration (Dieterich) Paramedian approach (Janik) Volume of CSF removed (Kuntz) Prevention of PLPHA *Unproven studies – some are equivocal and further research may illicit some benefit

15. PLPHA & Needle Size • Numerous studies (meta-analysis - Halpern) have clearly demonstrated that the smaller the needle, the lower the IR of PLPHA (Cutting Needles)

16. ED study (Seupaul) • Prospective, observational, multicentre study • 20G Quincke vs 22G Quincke (EP’s choice) • PLPHA was determined by f/u call in 7 days • Mean age 39 yoa

17. Of those 12 pts with PLPHA in the 20G group • 4(33%) required hospitalization for EBP • Not a great study (non-consecutive enrolment, 25% lost to f/u, published as letter to the editor), but ONLY ED data we have

18. What Size is best? • The smaller the needle, the lower the risk of PLPHA – • But… also more time is required to get the CSF(Carson) • No statistically significant difference in success rates between large and small spinal needles (Halpern)

19. CSF Flow Rates & LP Needles Assuming 6mL 17 minutes 5 minutes 3 minutes

20. Can we aspirate CSF to speed up process? • Prospective study, 100 consecutive pts • Mean age 60 yrs, Alzheimer's patients • 20G W • PLPHA rate only 4% • They concluded that aspirating CSF is safe Poorly designed study – cannot glean any useful info from this

21. See, smaller is better!!! • 22G provides an optimal balance between minimizing PLPHA rates and adequate CSF flow rates. • If someone is at particularly high risk of PLPHA • I.e. young, female, prior PLPHA • Could consider trying 25G (available in the ED)

22. Non-Cutting (aka pencil-point, atraumatic, blunt) Whitacre, Sprotte, Gertie-Marx Whitacre 22G $10.70 Cutting Quincke, Atraucan Quincke 22G $2.84 Needle Type Italicized needles are the brands available for us in the ED/CHR

23. What’s the rationale for atraumatic needles? • Separate the dural fibers rather than cutting them allowing the hole to seal better • “tear” the dural membrane creating a ragged edge that promotes an inflammatory response, resulting in a more rapid seal of the CSF membrane Atraumatic Cutting

24. Cutting vs Atraumatic(Strupp) • RCT, double blind(?) of 22G Quincke vs Sprotte • N=230 pts, Diagnostic LP’s by Neurology • Excluded those with recent HA, • IR of post-LP HA • Cutting = 24.4% • Atraumatic = 12.2% • ARR = 12.2% • NNT  8 Note IR is different than ED study -no cannot compare baseline pt data -no mention of how PLPHA was Dx

25. Are they harder to use? • RCT of 20G atraumatic vs cutting (Thomas) •  PLPHA w/ ARR of 26% • Residents performed all LP’s and they found • Non-cutting more difficult to use (p <0.05) • No-cutting required attempts/increase failure (not s.s.) • A significant RF for failure was increasing BMI • Neurologists/Anesthetists Experience • Small learning curve, but then no difference • Dr. Tang (Anesthesia) feels there is no difference

26. Summary of Studies • No ED studies • But we can extrapolate from Neuro studies • ATRAUMATIC needles are clearly better • Worth the marginal increase in cost

27. Our LP trays • Current trays in ED have 22G quincke (some have both 20G and 22G) • 20G, 22G, 25G Whitacres available in trauma bay (std 3.5”) • Longer atraumatic needles available from central supply/radiology suite

28. Tips for the Atraumatic needle • Need to use introducer (18-19G needle adequate for 22G W) • Insert introducer 2/3 of length initially (more if needed) • Slightly different feel since you are “spreading tissue” rather than cutting through • May not feel “pop” • If unsuccessful – consider switching to Quincke

29. Re-Insertion of Stylet • Theory is that withdrawal of needle without the stylet would result in arachnoid fibers being withdrawn leading to a persistent dural leak because of a hole that is no as easily healed • One case report of nerve transection with replacement of stylet

30. RCT of re-inserting stylet or not • 600 pts – 300 in each arm, atraumatic needle used (21G Sprotte) • IR of PLPHA • Re-inserted stylet – 16.3% • Not Re-inserted stylet – 5% • Severity of HA was worse in those who did not have stylet re-inserted • No studies on cutting needles but felt to be beneficial

31. Bevel Orientation • Theorized that needle insertion parallel to longitudinal fibers result in less leakage because bevel pushes fibers away rather than transecting them • Practically bevel up (notch on hub up) when pt in LLD

32. Evidence for Bevel Orientation • In vitro studies with human dura • Significantly decreased rate and amount of CSF leakage if bevel oriented parallel to dural fibers (Ready et al.) • In vivo study (Flaaten et al.) • RCT in spinal anasthesia pts, 27G Q • IR of PLPHA • Bevel Parallel = 3.8% • Bevel Perpendicular = 22.6%

33. Summary • Difficult to extrapolate to our patient population, needle size, diagnostic LP’s • Bevel orientation likely only significant if using cutting needle • But in considering evidence, recommend orienting bevel appropriately if using cutting needle –When seated bevel orientation is different!

34. Management of PLPHA • Caffeine • EBP • Triptans • Saline into Epidural space • Prophylactic EBP • ACTH • Aminophylline Will not discuss these. Not appropriate therapeutic options in the ED

35. Caffeine • Theory is that caffeine (oral or IV) leads to cerebral vasoconstriction • Paucity of evidence (Camann, Sechzer) • Worth a trial if patient only has mild Sx, presents early, contra-indication to EBP or unwilling to have EBP • Dose: • 300mg PO TID until ASx • Can give initial IV dose of 500mg caffeine benzoate given over 4H

36. EBP

37. EBP • First introduced in the 1960’s after it was noted that bloody taps had less PLPHA • Theory is that clotted blood seals the CSF leak • Procedure involves injecting 10-20mL of autologous blood into the epidural space • Contra-indications: 1)Coagulopathy, 2)IC mass lesion, 3) Fever>38.0, 4)overlying skin infection/bacteremia

39. Definitive evidence that EBP is effective • How effective is dependent on patient population, pre-morbid factors, etc? • Likely somewhere in the neighbourhood of 75-80% • Most data is from spinal anesthesia literature • Timing of EBP is very debatable. • Some evidence that one should wait at least 24H after LP before doing EBP- success rate (Loeser, Vilming) • Tx medically in the mean time • If severe speak to anesthesia even if w/i 24H.

40. Complications of EBP • Failure - 5-40% • Back pain (typically minor) - 35% • Neck pain – 1% • Fever (usu < 48H) – 5% • Bleeding, infection (meningitis), arachnoiditis, CN palsies and repeat dural puncture have been reported infrequently

41. Triptans & PLPHA • Most evidence for triptans and PLPHA are case reports/series • Small study by Connelly et al. of 10 pts • Randomized to SC sumatriptan or saline • No difference in VAS scores but grossly underpowered

42. Approach to the Difficult LP • Fan-technique for anesthesia • If excess soft tissue is your obstacle – get longer needle from interventional radiology • If elderly – consider paramedian approach • Consider changing position • Some u/s evidence that seated with feet supported provides widest interspinous space • Fluoroscopy

43. 5-7.5MHz linear probe • Transverse plane @ level of iliac crest • Identifies midline by shadow cast by spinous process -> mark midline

44. Interspinous Space Spinous Process • Rotate the probe into a longitudinal axis • Identify the interspinous space • Proceed as normal trying to enter as close to inferior S.P. as possible

45. Summary – Preventing PLPHA • Atraumatic needles (Whitacre) – Class I Evidence • Smaller needles – Class I • NNT =5 to prevent 1 PLPHA • for 22G Whitacre vs 20G Quincke • Re-insert stylet prior to removal – Class I,III • If unsuccessful with atraumatic needle try cutting needle & orient bevel appropriately – Class I

46. Summary - Managing PLPHA • Best strategy is to try & avoid PLPHA • If patient develops PLPHA • Moderate-severe  speak to anesthesia about EBP • Consider medical Tx (analgesics/caffeine) • ?Within 24H • CI to EBP • Mild Sx • Refuses EBP

47. Questions???

48. References • Armon C. Addendum to Assessment: Prevention of post-lumbar puncture headaches. American Academy of Neurology. Neurology 2005; 65:510-2. • Camann WR. Effects of oral caffeine ton postdural puncture headche. A double-blind placebo controlled trial. Anesthesia & Analgesia 1990;70:181-4. • Carson D. et al. Choosing the best needle for diagnostic lumbar puncture. Neurology 1996; 47:33-37. • Connelly NR. et al. Sumatriptan in patients with postdural puncture headaches. Headache 2000; 40:316-18 • Dieterich M. et al. Incidence of PLPHA is independent of daily fluid intake. Eur Arch Psychiatry Neuro Sc 1988; 237:194-6. • Evans RW. et al. Assessment: Prevention of PLPHA.Neurology 2000; 55(7):909-14. • Halpern S. et al. Postdural Puncture Headache and Spinal Needle Design: Metaanalyses. Anesthesiology 1994; 81: 1376-1383. • Holdgate A. et al. Perils and pitfalls of lumbar puncture in the ED. Emergency Medicine 2001;13:351-358. • Kuntz KM. Et al. PLPHA: Experience in 501 consecutive procedures. Neurology 1992; 42: 1884-87.

49. References • Flaaten H. et al. Puncture technique and postural postdural puncture headache. A randomised, double-blind study comparing transverse and parallel puncture.Acta Anasthesiology Scandanavia 1998 Nov;42(10):1209-14. • Janik R. Post spinal headache. Its incidence following the median and paramedian techniquesAnaesthesist. 1992 Mar;41(3):137-41. • Loeser, E.A., Hill, G.E., Bennet, G.M. and Sederberg, J.H., Time vs. success rate for epidural bloodpatch, Anesthesiology, 2 (1978) 147-148. • Peterson M. et al. Bedside u/s for difficult lumbar puncture. J of Emerg Med 2005; 28:197-200. • Ready et al. Spinal needle determinants of rate of transdural fluid leak.Anasthesia and Analgesia 1989 Oct;69(4):457-60. • Samdani A. et al. Subdural hematoma after diagnostic lumbar puncture. Amer J Emerg Med July 2004;316-7. • Sechzer PH, et al. Post-spinal anesthesia headache treated with caffeine: evaluation with demand method—part I. Curr Ther Res 1978;24:307-312.

50. References • Seupaul RA et al. Prevalence of Post Dural Puncture HA after ED performed LP. Acad Emerg Med; May 2003. • Seupaul RA. et al. Prevalance of postdural HA after ED lumbar puncture. American Journal of Emergency Medicine 2005;23:913-14. • Strupp M. et al. “Atraumatic” Sprotte needle reduces the incidence of PLPHA. Neurology, 2001; 57:2310-12. • Strupp M. et al. Incidence of post-lumbar puncture syndrome reduced by reinserting the stylet: a randomzed prospective study of 600 patients. J Neurology 1998; 254:589-92. • Thoennissen J. et al. Does bed rest after cervical or lumbar puncture prevent HA. CMAJ 2001; 165: 1311-1315. • VilmingS. et al. When should an epidural blood patch be performed in postlumbar puncture headache? A theoretical approach based on a cohort of 79 patients.Cephalalgia July 2005; 25(7):523-7.