Body fluids—CSF Flashcards
functions of CSF
- supplies nutrients to nervous tissue
- removes metabolic wastes
- produces mechanical barrier to cushion CNS
3 layers that line CNS
meninges
- dura mater
- arachnoid mater
- pia mater
space where CSF flows
subarachnoid
produce CSF
choroid plexuses
—- mL/hour of CSF is produced
20
2 processes that contribute to CSF production
- filtration under hydrostatic pressure across capillaries of choroid plexuses
- active transport secretion by choroid epithelial cells
reabsorb CSF, regulating CSF pressure and volume
arachnoid villi
total volume CSF
adults: 140-170 mL
neonates: 10-60 mL
control and filtration of blood
bidirectional transport
blood brain barrier
lumbar puncture occurs where?
between 3rd, 4th or 5th vertebrae
where do CSF tubes go?
- chemistry/serology
- micro/PCR
- hematology
CSF sample handling & storage
highly contagious
never spin uncapped
Storage
chem/sero: freeze
micro: RT
heme: refrigerate
can remove up to —- mL CSF on an adult
20
ways to describe CSF appearance
- crystal clear
- cloudy
- turbid
- milky
- xanthochromic
- hemolyzed/bloody
causes of turbid CSF
- protein
- lipid
- infection
causes of xanthochromic CSF
pink, orange or yellow
- RBC degradation products
- serum bilirubin (prematures)
- carotene
- high protein
- melanoma pigment
CNS production of IgG indicates…
MS
causes of bloody CSF
- subarachnoid hemorrhage
- traumatic tap
how to distinguish traumatic tap from subarachnoid hemorrhage?
- distribution of blood (equal in all tubes or decreases)
- clot formation (traumatic)
- xanthochromic supernatant (hemorrhage)
- macrophages with RBCs, hemosiderin (hemorrhage)
RBCs begin to lyse in CSF within…
—–% WBCs will lyse within 2 hours
1 hour
40
for a proper CSF dilution, ——- cells/large square should be seen
10-100
if <—– cells are counted in CSF, count more squares
40
RBCs in CSF can be lysed with…
3% acetic acid
concentrates cells in CSF for a diff
cytocentrifugation
