Cerebrospinal Fluid Flashcards
Definition
Fluid that occupies spaces of the CNS
Surrounds the brain and spinal cord
Meninges
Layers of the brain
Membranes covering Brain and Spinal Cord
Dura Mater
Leptomeninges
Dura mater
Outside layer
Leptomeninges
Arachnoid mater
Pia mater
Arachnoid mater
Between the Dura mater and Pia mater
Considered to be part of the Leptomeninges
Pia mater
Inner most membrane
Considered to be part of the Leptomeninges
Primary production of CSF
Choroid plexus
Mechanism of production
Filtration under hydrostatic pressure
Modified by active transport and selective absorption
Rate of CSF production
Approximately 0.35 ml/min or 21 ml/hr
Total Adult Volume of CSF
140-170 mL
Total Neonate Volume of CSF
10-60 mL
Percentage of turnover CSF
14% per hour
Reabsorption through ventricle
CSF Function
Supplies nutrients
Removes waste
Blood/Brain barrier
Cushions and Lubricates
CSF Collection
Lumbar Puncture or Spinal Tap
Between 3rd and 4th or 4th and 5th Lumbar vertebrae
CSF Tubes in specific order
1 - Chemistry/serology
2 - Microbiology (never uses first tube due to poss contam)
3 - Hematology
4 - Hematology (if possible to obtain 4 tubes)
Intracranial pressure monitored
Prevents damage to neural tissue
Determine safe amount of fluid to remove
Reflection of size of CSF reservoir
Indication of disease
CSF Analysis Time Frame
Always considered a STAT sample
- Due to less friendly environment for cells
- Cells degrade quickly with no nutrients
Must be processed within 45 minutes
Quality Control for CSF
Daily Counts
Monitor diluent for contamination
Monitor centrifuge speed and timer
Appearance of typical CSF
Color - colorless
Clarity - clear
Normal TNC Count
0-5/cumm
100% mononuclear (lymphs and monocytes)
Normal RBC Count
0/cumm
Normal Glucose level
2/3 of plasma glucose
(bacterial infections cause glucose to decreased)
Normal Protein level
15-45 mg/dL
(could increase due to blood or meningitis)
Other chemical analysis
Lactate, Glutamine, Enzyme
Lactate increase
in bacterial meningitis
Glutamine increase
Liver disease
Two reasons for Bloody, pink, red
Hemorrhage
Traumatic Tap
Hemorrhage
Xanthochromic supernatant (red color)
Blood amount consistent between tubes 1 and 3
- long term bleed
- supernatant will have a yellowish/reddish hue
Traumatic Tap
Capillary hit on insertion of needle
Clear supernatant
Blood amount decreasing between tubes 1 and 3
- Clots may be seen
CSF Hazy or Cloudy
Increased number of cells
Increased protein
X-ray contrast media
Microorganisms
CSF Increased RBCs
Hemorrhage
CVA/Stroke
Traumatic Tap
Bone Marrow Contamination
Neutrophils increased in CSF
Bacterial meningitis (only report bacteria present)
Early viral meningitis
Hemorrhage
Contamination
nRBCs increased in CSF
Hemorrhage
Contamination (Bone Marrow or Blood)
Lymphocytes increased in CSF
Viral meningitis
TB, fungal infection
Multiple sclerosis
Monocytes increased in CSF
Inflammation
Clean up
Post Hemorrhage
TB
Eosinophils increased in CSF
Parasitic infection
Hydrocephalic Shunts
CNS Eosinophilic Leukemia (VERY RARE)
Blasts present in CSF
CNS involvement of Leukemia
Other Malignant Cells Present
Metastatic Solid Tumors
Lymphoma
Macrophages Present
Clean up cells
Post hemorrhage
TB
Plasma Cells
Lymphocytic Reaction
Multiple sclerosis
Multiple myeloma
Other cells Present
Choroidal Cells
Ependymal Cells
Pia Arachnoid Cells
Increased Glucose levels
Hyperglycemia or glucose loading
Decreased Glucose levels
Disorder of glucose transport
Metabolism of glucose by organisms or cells
Glucose consumption by tumor or abcess
Increased Protein levels
Most useful indicator
Lysis of contaminant blood
Infection and/or bleeding
Increased production of protein
Obstruction
Decreased removal of protein
Decreased Protein levels
Result of lumbar puncture
CNS Leakage
Increased removal of protein
