FINALS - CSF Flashcards
Considered as 3rd Major body fluid
Cerebrospinal Fluid
FUNCTIONS of CSF
- Supply nutrients to the CNS
- Remove metabolic waste
- Produce a mechanical barrier to cushion the
brain and spinal cord against trauma
Lines the brain and spinal cord
Meninges
outer layer, lines the skull and vertebral
canal
Dura Mater
▪ spider-like, filamentous inner
membrane
Arachnoid mater
▪ innermost layer
▪ lines the surface of the brain and
spinal cord
Pia Mater
▪ In between Arachnoid mater and Pia
mater
o where CSF flows
Subarachnoid space
specific part of the brain that produces CSF
Choroid Plexus
Choroid Plexus Ventricles
○ Choroid plexus of the third ventricle
○ Choroid plexus of the fourth ventricle
○ Choroid plexus of the lateral ventricle
Choroid Plexus are capillary networks that form the CSF from plasma by mechanisms of:
- selective filtration under hydrostatic
pressure; - active transport secretion
T or F
The chemical composition of the CSF resemble an ultrafiltrate of plasma
False
Rate of CSF Production
20 ml/hr
Reabsorbs CSF
Arachnoid vili / Granulations
● tightly fitting junctures structure of endothelial cells in choroid plexus
● Protects the brain from chemicals and other
substances circulating in the blood that can harm the brain tissue
Blood Brain Barrier (BBB)
Disruption of BBB allows substances to enter the CSF such as:
WBC
Protein
Other Chemicals (High Molecular Weight)
CSF SPECIMEN COLLECTION
○ Lumbar puncture/tap
■ (Between the 3rd, 4th, or 5th lumbar vertebrae)
○ Cisternal puncture
CSF SPECIMEN Volume to be collected
- Up to 20 ml collected under normal pressure, which is approximately 15% of the estimated total CSF volume
IF CSF is not normal (lesser, greater), what is the volume to be removed?
only 1-2 ml
Normal CSF Volume of ADULT
90-150 mL
Normal CSF Volume of NEONATES
10-60 mL
CSF Tube 1 - Lab Section
● Chemistry
● Immunology
● Serology
CSF Tube 2 - Lab Section
● Microbiology
○ Gram Stain
○ Culture and Sensitivity
CSF Tube 3 - Lab Section
● Hematology (Cell count)
● Cytology studies
CSF Tube 4 - Lab Section
● Microbiology (better exclude skin
contamination)
● Serology (for additional serologic test)
○ Tubed used to check cellular
contamination=
Tube 1 and 4
CSF Appearance - Crystal Clear
Normal
CSF Appearance - Cloudy, Turbid, Milky
● Increase WBC= >200/uL
● Increase RBC= >400/uL
● Presence of Microorganisms
● Increased Proteins and Lipids
CSF Appearance - Xanthochromic - PINK
slight amount of oxyhemoglobin
CSF Appearance -Xanthochromic - YELLOW
Bilirubin
CSF Appearance - Xanthochromic - ORANGE
in case of heavy hemolysis
CSF Appearance - Xanthochromic - BROWNISH
Methemoglobin Formation
CSF Appearance - Xanthochromic - OTHER CAUSES
● Increase dietary carotene
● Increase rifampin intake
● Increase melanin
● Normal neonate
● Protein concentration exceeding 150mg/dL
● Previous traumatic tap
CSF Appearance - Bloody/Grossly bloody
● RBCs: >6000/uL due to
○ Traumatic tap
○ Intracranial hemorrhage/ Cerebral hemorrhage
CSF Appearance - Oily
Radiographic contrast dye
CSF Appearance - Clotted
● Protein and clotting factors
● Meningitis
● Froin’s syndrome
CSF Appearance - Pellicle
Tubercular meningitis
Clear Appearance - DILUTION
Undiluted
Slightly Hazy Appearance - DILUTION
1:10
Hazy Appearance - DILUTION
1:20
Slightly cloudy Appearance - DILUTION
1:100
Cloudy/Slightly bloody Appearance - DILUTION
1:200
40% of WBC disintegrates within
2 hours
CSF WBC Count diluting fluid
3% glacial acetic acid (HAc) with Methylene Blue
Normal CSF WBC Count of Adults
0-5 WBCS/ul
Normal CSF WBC Count of Neonates
0-30 WBCs/ul
