Post on 20-Jan-2016
The Lumbar Puncture:The Lumbar Puncture:This (Really) Is Spinal TapThis (Really) Is Spinal Tap
OutlineIndications and contraindications
Use of CT scan
Procedural technique
Potential complications
Initial CSF studies and interpretation
Initial management of meningitis
History of LP
1891 by Heinrich Irenaeus QuinckeGerman Internist born in 1842
Died in Frankfurt in 1922
Designed to treat neonatal hydrocephalus
Now a famous rock band (Spinal Tap)
Quincke H. Ueber Hydrocephalus. Verhandl Cong Inn Med. 1891;10:321.
Indications
The time to do an LP is the time when you wonder, “should I do an LP?”
Particularly if you’re considering encephalitis or meningitis.
SAH (if the CT is normal)Meningitis/EncephalitisInflammatory polyneuropathies
MS, Guillan-Barre, etc.
Carcinomatous meningitis, tuberculous meningitisCSF disorder (hydrocephalus, NPH, pseudotumor cerebri)Therapeutic (i.e., intrathecal chemo, anesthesia)Injection for myelography
ContraindicationsIncreased ICP
Exam: Papilledema, focal neurologic examHistorical concerns: recent trauma/seizures
Focal infection at the LP site
Severe Coagulation defects
Abnormal Anatomy/Mass
Spinal Fracture
Spinal Hardware can be a relative contraindication
Head CT
Never let a head CT delay the institution of antibiotics (30 minute treatment time).
Head CT for subarachnoid, not meningitis
Study by Gopal in Arch Int Med 1999:15% with CT had an abnormality, but only 2.7% with a lesion that contraindicated LP
Three clinical Predictors pre-LP:• Altered mental status• Focal Exam• Papilledema
301 Patients
Risks Factors for Mass Effect on CTAge >60ImmunocomprimisedHistory of CNS disease/tumorNeurologic AbnormalitySeizureDepressed mental status
NPV 97%Other 3% did not have issues with LP
Indications for a head CTIncreased ICP
Altered MS, papilledema, focal neuro exam
History of recent head trauma or new seizures
ImmunosuppressionNeutropenia, HIV
Recurrent meningitis
Recent OM, sinusitis for possible parameningeal focus (relative)
Procedural techniqueGoal is to sample the CSF from the subarachnoid space at L3-L4 or L4-L5.
Nerve roots of the cauda equina are at this level, but they are simply pushed over.
The spinal cord usually ends at L1-L2.
Needle routeSkin
Supraspinous and interspinous ligaments
Ligamentum flavum
Epidural space
Dura
Subarachnoid membrane and space
Procedural stepsH&P, consider need for pre-LP CT scan
ABX +/- steroids?
Informed consent
Gather your materialsLP kitCleaning solution (Betadine or Chlora-Prep)Extra LidocaineSterile GlovesExtra sterile tubes (if necessary)Chux padsExtra Needle (atraumatic or smaller gauge)
Consider procedural sedationDiazepam 5mg, Lorazepam 1mg, Midazolam 1mg
Positioning, Positioning, Positioning
Lateral decubitus position or sitting
Fetal position to widen space between the spinous processes
This is key
Palpate the iliac crests to locate L4/L5, use thumbs to locate
Make an indentation with a pen cap, or other device
Mark should not wash off
Procedural stepsOpen the kit.
Pour betadine into tray, drop extra needles, etc
Put on sterile gloves.
Prepare the area in a circular fashion with betadine or povidone-iodine.
Drape.
Inject 1-2% lidocaine at the site.
Needle Position
Bevel parallel or perpendicular to spine?
Parallel!Bevel should be parallel to dural fibers
Less cutting and more separation
Reported 50% decrease in post-LP headache
Procedural stepsWait 3-5 minutes for the anesthetic effect
Introduce needle parallel to the bed, bevel perpendicular to spine, in a 30-45 degree cephalad angle
Progress through the layers slowly
Feel the “pop” going into the subarachoid space.
Don’t count on this…
Remove the stylet and look for CSFSome remove stylet once in intraspinus ligaments
Troubleshooting
Needle angle
Bone spur?
Positioning?
Procedural stepsAttach the manometer (instruct patient to relax) and check the opening pressure
Collect four tubes of 2-5cc of CSF
Replace the stylet and remove the needleA strand of arachnoid may be drawn out with needle600 patient RCT (Strupp NEJM 1997) showed 3x reduction in headache (16% vs. 5%, p<0.005)
Put a bandage at the site and remain supine for 2 hoursNon-significant benefit in several studies
Alternate Needles
Newer ‘atraumatic needles’Sprotte needle designed in 80s
Now made by a company called ‘Pajunk”
Sprotte G, Schedel R, Pajunk H, et al. An “atraumatic” universal
needle for single-shot regional anesthesia: clinical results
and a 6 year trial in over 30,000 regional anesthesias. Reg
Anaesth 1987;10:104–108.
Atraumatic Meta-Analysis
Lenaerts used 20 G “Yale” instead of QuinckeObviously, a poor study
Friends don’t let friends associate with Yale
Atraumatic Insertion
Atraumatic cannot penentrate skin very well
Also is more flexible
Can use 18 gauge as guide
Atraumatic Spinal Needle
Potential complications
Brain herniationIf you get neurologic changes, remove needle immediatelyReverse Trendelenburg, hyperventilate and call Neurosurgery!
Postspinal headacheMost common complication (10-15%)Use smallest gauge needle possibleTreat with analgesics/epidural blood patchCaffeine 500mg IV x1
Local bleeding/infection
Nerve trauma/pain
CSF studiesTube 1: cell count/diffTube 2: protein, glucose, other chem (OCBs, MBP, etc.)Tube 3: Gram stain, culture, other micro (HSV PCR, etc.)Tube 4: cell count/diff, cytology
Special studies: Enteroviral, HSV PCRVDRL, Cocci, Crypto, AFB, Fungal, etc.Cytology (Presence of CNS malignancy)Oligoclonal bands, myelin basic protein, etc.Consider saving an ‘extra tube’ (especially for cytology)
FOR THE LOVE OF GOD, PLEASE HAND-CARRY ALL CSF TO FOR THE LOVE OF GOD, PLEASE HAND-CARRY ALL CSF TO THE LAB YOURSELF.THE LAB YOURSELF.
AccessioningIF IMPORTANT, DO IT YOURSELF!
In CHCS go to lab testsType Now, Ward/clinic collect, STATType CSF
• Protein, Glucose, Cell count & Diff, Culture
Type Gram• Sample name ‘CSF’
Other studies as necessary, may need MMO• Miscellaneous Mail Outs, for Oligoclonal Bands• Ordering these can be a pain in the @$$!!!
CSF interpretation
Opening pressureNormal 6-18 cm H2O
Falsely elevated in sitting position or a tense patient
Fluid appearanceFluid should appear clear
SAH: compare tubes 1 and 4; xanthochromia• Xanthochromia should be determined by spectroscopy
• We don’t have a spectrometer… So you just look at it
CSF interpretationCell count
“Normal” is no more that 5 wbc’s and 1 neutrophilFor bloody taps: 700 rbc/ 1 wbcIf dump the CSF from the manometer, you should be ashamed!
Protein – normal 15/40 mg/dL1 mg increase for 1000 rbc’sVery elevated in infections, mildly elevated in inflammatory disease
Glucose – normal 45-80 mg/dLNormal is >0.6 of blood glucose level Ratio of <0.4 has positive LR of 13
CSF MicrobiologyIf important, look at it yourself!Gram stain
Always check with Microbiology regarding the gram stain results80% positive with bacterial pathogenGPR: think Listeria!
CulturesReview plates daily with Microbiology
Call Childrens for HSV, EBV results in 1-2 day
Meningitis: Clinical PresentationStudy by Thomas, et al. CID, 2002
Headache - 92%
Fever - 71%
N/V - 70%
Photophobia - 57%
Stiff neck - 48%
Seizure - 9%
None were predictive (post-test odds .42-.57)
Examination: Meningitis
Exam:
Petechiae/rash
Genital lesions-usually not present with HSV
Kernig’s: pain with knee extension
Brudzinki’s: flexion of neck leads to hip/knee flexion
Nuchal rigidity
Papilledema not consistent with meningitis alone
Physical examinationKernig’s:
Sens 5%, Spec 95%, PPV 27%, NPV 72%
Brudzinski’s:Sens 5%, Spec 95%, PPV 27%, NPV 72%
Nuchal Rigidity:Sens 30%, Spec 68%, PPV 26%, NPV 73%
Absence does NOT r/o disease!
Meningitis
Bacterial:Strep pneumoniae, N. meningitidis, H. flu, Listeria, GNR’s.
Aseptic:Viral: enterovirus, HSV, arbovirus, HIV, WNV.
Bacterial: partially treated bacterial, TB
Spirochetes: Lyme, syphilis
Fungi: Cocci, Cryptococcus, Histo
MeningitisAseptic:
Amoebae, toxo, rickettsia, othersDrugs: NSAID’s, sulfa, IVIG, INHRheumatic diseases (SLE)CancerSarcoid
Organism depends on:AgeMedical Conditions/Immune StatusVaccine History
Bacterial meningitis
Neonates: GBS, E. coli/GNRs, Listeria
1-3 Mos.: GBS, Listeria, S. pneumo, H. influenzae
3mo-9 yr.: S. pneumoniae, N. meningitidis
9-50 yr.: S. pneumoniae, N. meningitidis
>50 yr.: S. pneumoniae, N. meningitidis, Listeria, GNR’s
TreatmentDroplet isolation for 24-48 hours.
Empiric antibiotics:Ceftriaxone 2 g IV q12hVancomycin 15 mg/kg IV q12h (generally 1-1.5 g IV q12h)Add ampicillin 2 g IV q4h for coverage of Listeria monocytogenes if patient is >50 years old, immunosuppressed, pregnant, or alcoholic.
Special situations:Trauma/shunt – cefepime + vancomycinImmunocompromise – vancomycin/cefepime/ampicillinPCN allergy – vancomycin/TMP-SMX/+/- chloramphenicol
TreatmentAcyclovir in cases of HSV
+PCR in CSF in cases of meningitisEmpirically in cases of encephalitis 10 mg/kg IV q8h – maintain good UOP
Steroids Dexamethasone 10 mg IV q6hDose before antibiotics. Reduces TNF.
Increased ICP:ICU management, elevation of head to 30 degrees, mannitol, hyperventilation to pCO2 of 30mmHg, steroids.
Questions?Questions?
References
• Practice parameters: Lumbar Puncture. Neurology, 1993; 43:625
• Special Techniques for neurologic diagnosis in Principles of Neurology, 5th, 1993. New York: McGraw-Hill, p 11-16
• Cooper JR: Routine use of CT prior to lumbar puncture. Br J Rad, 1999; 72:319
• Gopal AK, et al:Cranial CT before lumbar puncture. Arch Intern Med, 1999; 159:2681.
• Waldman W and Laureno R: Precautions for lumbar puncture: a survey of neurologic educations. Neurology, 1999; 52:1296.
References
• Converse GM, et al: Alteration of CSF findings by partial treatment of bacterial meningitis. J Pediatr, 1973; 83: 220.
• Negrini B, et al: Cerebrospinal fluid findings in aseptic versus bacterial meningitis. Pediatr, 2000; 105:316
• Tunkel AR and Scheld WM: Acute bacterial meningitis. Lancet, 1995; 346:1675.
• Greenlee JE: Approach to diagnosis of meningitis: Cerebrospinal fluid evaluation. Infect Dis Clin NA, 1990; 4:583.
• Quagliarello VJ and Scheld WM: Treatment of bacterial meningitis. NEJM, 1997; 336:708.
References
• Flaatten H, et al:Puncture technique and postural postdural puncture headache. A randomized double-blind study comparing transverse and parallel puncture. Acta Anaesth Scand, 1998; 42:1209.
• Sharma A: Preventing headache after lumbar puncture. BMJ, 1998; 317:1588.
• Nel MR: Epidural blood patching can be used to treat headache. BMJ, 1998; 316: 1019.
• Kaplan SL: Clinical presentations, diagnosis, and prognostic factors of bacterial meningitis. Infect Dis Clin NA, 1999; 13:579.