Difference between revisions of "Lumbar puncture"

(Created page with "Correction for bloody tap Nl Ratio: 700 RBCs to 1 WBC Protein subtract 1mg/dL per 1000 RBCs *General Contraindications: A. Infection at LP site B. Severe thrombocytopenia...")
 
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Correction for bloody tap
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==Correction for bloody tap==
 +
#Nl Ratio: 700 RBCs to 1 WBC
 +
#Protein subtract 1mg/dL per 1000 RBCs
  
Nl Ratio: 700 RBCs to 1 WBC
+
==General Contraindications==
 
+
# Infection at LP site
Protein subtract 1mg/dL per 1000 RBCs
+
# Severe thrombocytopenia (platelets <50) or bleeding diathesis or INR >1.5
 +
# Mass lesion suspected (do CT or MRI first)
  
 +
==CT findings that prohibit LP==
 +
# Midline shift
 +
##Look for unequal pressures between the 3 cerebral compartments (left/right supretentorial compartments, posterior fossa)
 +
##Look for intracerebral masses not causing midline shift
 +
# Obsutrictive hydrocephalus
 +
## Look for enlargement of ventricles prox to lesions and normal ventricles distal (especially 4th ventricle)
 +
# Basilar cisterns compressed
 +
## Look for lateral/3rd ventricles may be small due to diffuse cerebral edema or enlarged due to obstr. hydroceph. +/- shift
 +
# Posterior fossa mass
 +
## Look for displacement/compression of 4th ventricle
 
   
 
   
 
*General Contraindications:
 
 
A. Infection at LP site
 
 
B. Severe thrombocytopenia (platelets <50) or bleeding diathesis or INR >1.5
 
 
C. Mass lesion suspected (do CT or MRI first)
 
 
 
 
CT findings that prohibit LP
 
 
A. Midline shift
 
 
* Look for unequal pressures between the 3 cerebral compartments (left/right supretentorial compartments, posterior fossa)
 
* Look for intracerebral masses not causing midline shift
 
B. Obsutrictive hydrocephalus
 
 
* Look for enlargement of ventricles prox to lesions and normal ventricles distal (especially 4th ventricle)
 
C. Basilar cisterns compressed
 
 
* Look for lateral/3rd ventricles may be small due to diffuse cerebral edema or enlarged due to obstr. hydroceph. +/- shift
 
D. Posterior fossa mass
 
 
* Look for displacement/compression of 4th ventricle
 
 
 
 
Consider contrast CT/MRI
 
Consider contrast CT/MRI
 
 
  
 
(source: Emergency Radiology: Case Studies Schwartz)
 
(source: Emergency Radiology: Case Studies Schwartz)
  
+
==CT Head before LP==
 
+
In with meningitis suspected:
CT Head indicated before LP in pts with suspected meningitis with:
+
# AMS
 
+
# Focal Neurologic deficit
1) AMS
+
# Papilledema
 
+
# Head Trauma or h/o CNS disease (recent or remote)
2) Focal Neurologic deficit
+
# New Onset Sz (<1 wk prior to ED visit)
 
+
# HIV + / AIDS or any immunocompromised (transplant pt, steroids, cancer) patient
3) Papilledema
+
# Age > 60.
 
 
4) Head Trauma or h/o CNS disease (recent or remote)
 
 
 
5) New Onset Sz (<1 wk prior to ED visit)
 
 
 
6) HIV + / AIDS or any immunocompromised (transplant pt, steroids, cancer) patient
 
 
 
7) Age > 60.
 
  
 
-Hasbun, R. et al, (Yale), NEJM, Dec 13, 2001. (prospective, 301 pts)
 
-Hasbun, R. et al, (Yale), NEJM, Dec 13, 2001. (prospective, 301 pts)
  
+
===PEDIATRICS (Marianne)===
 
+
# VP shunt
PEDIATRICS (Marianne)
+
# Febrile sx ?counts
  
1) VP shunt
 
 
2) Febrile sx ?counts
 
 
 
  
 
NORMAL WBC
 
NORMAL WBC
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Child: <7
 
Child: <7
 
 
  
 
*May also order: cytology, VDRL, AFB stain/culture (often requires lab medicine approval), fungal stain (fungal cultures often require lab medicine approval), Cryptococcal antigen (CrAg), India Ink, oligoclonal bands, MBP, Lyme titers, HSV PCR.
 
*May also order: cytology, VDRL, AFB stain/culture (often requires lab medicine approval), fungal stain (fungal cultures often require lab medicine approval), Cryptococcal antigen (CrAg), India Ink, oligoclonal bands, MBP, Lyme titers, HSV PCR.
  
+
==Laboratory Results==
 
+
===NORMAL===
NORMAL
 
 
 
 
Appearance Clear
 
Appearance Clear
  
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Pressure (cm H2O) 5-20
 
Pressure (cm H2O) 5-20
  
+
===Traumatic LP===
 
 
Traumatic LP:
 
 
 
 
1000 RBC for 1mg/dL protein
 
1000 RBC for 1mg/dL protein
  
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Xanthrochromia tube 4; results from RBC lysis and hemoglobin breakdown.
 
Xanthrochromia tube 4; results from RBC lysis and hemoglobin breakdown.
  
+
===HEMORRHAGE===
 
 
HEMORRHAGE
 
 
 
 
Appearance Bloody or xantho
 
Appearance Bloody or xantho
  
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Pressure (cm H2O) Usually Inc
 
Pressure (cm H2O) Usually Inc
  
+
===BACTERIAL MENINGITIS===
 
 
BACTERIAL MENINGITIS
 
 
 
 
Appearance Cloudy or purulent
 
Appearance Cloudy or purulent
  
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Pressure (cm H2O) Usually Inc
 
Pressure (cm H2O) Usually Inc
  
+
===FUNGAL MENINGITIS===
 
 
FUNGAL MENINGITiS
 
 
 
 
Appearance Clear or cloudy
 
Appearance Clear or cloudy
  
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LA assay for crypto antigen 80%.
 
LA assay for crypto antigen 80%.
  
+
===ASEPTIC/VIRAL MENINGITIS===
 
 
ASEPTIC/VIRAL MENINGITIS
 
 
 
 
Appearance Clear
 
Appearance Clear
  
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Pressure (cm H2O) N or I
 
Pressure (cm H2O) N or I
  
+
===TB MENINGITIS===
 
 
TB MENINGITIS
 
 
 
 
Appearance Cloudy
 
Appearance Cloudy
  
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Pressure (cm H2O) Usually I
 
Pressure (cm H2O) Usually I
  
+
===HERPES ENCEPHALITIS===
 
 
HERPES ENCEPHALITIS
 
 
 
 
Appearance Bloody or xantho
 
Appearance Bloody or xantho
  
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Pressure (cm H2O) N or I
 
Pressure (cm H2O) N or I
  
+
===NEOPLASM===
 
 
NEOPLASM
 
 
 
 
Appearance Clear or xantho
 
Appearance Clear or xantho
  
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Pressure (cm H2O) Usually I
 
Pressure (cm H2O) Usually I
  
+
===GUILLAIN-BARR===
 
 
GUILLAIN-BARR
 
 
 
 
Appearance Clear or cloudy
 
Appearance Clear or cloudy
  
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Pressure (cm H2O) Normal
 
Pressure (cm H2O) Normal
  
+
===NEUROSYPHILIS===
 
 
NEUROSYPHILIS
 
 
 
 
Appearance Clear & cloudy
 
Appearance Clear & cloudy
  
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Pressure (cm H2O) N or I
 
Pressure (cm H2O) N or I
  
+
==Lumbar Puncture Note==
 
+
#Consent
Lumbar Puncture Note (LP)
+
#Indication
 
+
#Pressure
Consent
+
#Color
 
+
#Amount
Indication
+
#Tests
 
+
#Interspace
Pressure
+
#Anesthesia
 
+
#Position
Color
+
#Pt. tolerance
 
 
Amount
 
 
 
Tests
 
 
 
Interspace
 
 
 
Anesthesia
 
 
 
Position
 
 
 
Pt. tolerance
 
 
 
 
 
 
 
  
 +
[[Category:Neuro]]
 
[[Category:Procedures]]
 
[[Category:Procedures]]

Revision as of 16:46, 9 June 2011

Correction for bloody tap

  1. Nl Ratio: 700 RBCs to 1 WBC
  2. Protein subtract 1mg/dL per 1000 RBCs

General Contraindications

  1. Infection at LP site
  2. Severe thrombocytopenia (platelets <50) or bleeding diathesis or INR >1.5
  3. Mass lesion suspected (do CT or MRI first)

CT findings that prohibit LP

  1. Midline shift
    1. Look for unequal pressures between the 3 cerebral compartments (left/right supretentorial compartments, posterior fossa)
    2. Look for intracerebral masses not causing midline shift
  2. Obsutrictive hydrocephalus
    1. Look for enlargement of ventricles prox to lesions and normal ventricles distal (especially 4th ventricle)
  3. Basilar cisterns compressed
    1. Look for lateral/3rd ventricles may be small due to diffuse cerebral edema or enlarged due to obstr. hydroceph. +/- shift
  4. Posterior fossa mass
    1. Look for displacement/compression of 4th ventricle

Consider contrast CT/MRI

(source: Emergency Radiology: Case Studies Schwartz)

CT Head before LP

In with meningitis suspected:

  1. AMS
  2. Focal Neurologic deficit
  3. Papilledema
  4. Head Trauma or h/o CNS disease (recent or remote)
  5. New Onset Sz (<1 wk prior to ED visit)
  6. HIV + / AIDS or any immunocompromised (transplant pt, steroids, cancer) patient
  7. Age > 60.

-Hasbun, R. et al, (Yale), NEJM, Dec 13, 2001. (prospective, 301 pts)

PEDIATRICS (Marianne)

  1. VP shunt
  2. Febrile sx ?counts


NORMAL WBC

Preterm: <25

Term: <22

Child: <7

  • May also order: cytology, VDRL, AFB stain/culture (often requires lab medicine approval), fungal stain (fungal cultures often require lab medicine approval), Cryptococcal antigen (CrAg), India Ink, oligoclonal bands, MBP, Lyme titers, HSV PCR.

Laboratory Results

NORMAL

Appearance Clear

Glucose (mg/dl) 50-75% serum

Protein (mg/dl) 15-45

Cell Count WBC 0-5

Differential 100% lymph, no PMN

Pressure (cm H2O) 5-20

Traumatic LP

1000 RBC for 1mg/dL protein

700 -1000 RBC gives 1 WBC

Xanthrochromia tube 4; results from RBC lysis and hemoglobin breakdown.

HEMORRHAGE

Appearance Bloody or xantho

Glucose (mg/dl) N or D

Protein (mg/dl) Inc but <1000

Cell Count RBC (<~50 okay)

(50-600 = gray zone)

(>600 c/w SAH)

Differential Same as blood

Pressure (cm H2O) Usually Inc

BACTERIAL MENINGITIS

Appearance Cloudy or purulent

Glucose (mg/dl) <40 or <40% serum

Protein (mg/dl) >100-500

Cell Count 100-100,000 (>5)

Differential >80% PMN

Pressure (cm H2O) Usually Inc

FUNGAL MENINGITIS

Appearance Clear or cloudy

Glucose (mg/dl) 20-40

Protein (mg/dl) 25-500

Cell Count 25-1000

Differential mono& lymph

Pressure (cm H2O) N or I

India ink 50% sensitivity

LA assay for crypto antigen 80%.

ASEPTIC/VIRAL MENINGITIS

Appearance Clear

Glucose (mg/dl) N or D

Protein (mg/dl) 50-200

Cell Count WBC 10-100

Differential Inc mono & PMN early, then lymph.

Pressure (cm H2O) N or I

TB MENINGITIS

Appearance Cloudy

Glucose (mg/dl) <40

Protein (mg/dl) 100-2000

Cell Count 50-500

Differential Most lymph, some PMN

Pressure (cm H2O) Usually I

HERPES ENCEPHALITIS

Appearance Bloody or xantho

Glucose (mg/dl) N or D

Protein (mg/dl) 50-100

Cell Count 20-500

Differential Mostly lymph

Pressure (cm H2O) N or I

NEOPLASM

Appearance Clear or xantho

Glucose (mg/dl) 40-80

Protein (mg/dl) 50-1000

Cell Count <100

Differential Mostly lymph

Pressure (cm H2O) Usually I

GUILLAIN-BARR

Appearance Clear or cloudy

Glucose (mg/dl) Normal

Protein (mg/dl) slight Inc

Cell Count <100

Differential Mostly lymph

Pressure (cm H2O) Normal

NEUROSYPHILIS

Appearance Clear & cloudy

Glucose (mg/dl) Normal

Protein (mg/dl) 40-200

Cell Count 200-500

Differential Mostly lymph & mono

Pressure (cm H2O) N or I

Lumbar Puncture Note

  1. Consent
  2. Indication
  3. Pressure
  4. Color
  5. Amount
  6. Tests
  7. Interspace
  8. Anesthesia
  9. Position
  10. Pt. tolerance