CSF Flashcards
A membranous three-layer coverings of brain and spinal cord.
Meninges
The third major body fluid.
CSF
Give three functions of CSF.
- Supply nutrients to the nervous system.
- Remove metabolic wastes.
- Produce a mechanical barrier to cushion the brain and spinal cord against trauma.
What are the three layers of meninges?
Dura Mater
Arachnoid Mater
Pia Mater
Tough mother, outermost layer
Dura Mater
Tender mother, innermost layer
Pia Mater
Spider-like, filamentous inner membrane
Arachnoid Mater
trabeculae are found in this space, which is filled with circulating CSF
subarachnoid space
where csf flows
subarachnoid space
composed of tight junctions of endothelial cells which makes up BBB
choroid plexus
What is the rate of production of choroid plexus?
20ml/hr
(500 ml/day; 0.3-0.4 ml/min)
prevents passage of many molecules
blood brain barrier
protects brain from toxins, infections, or other substances
blood brain barrier
it reabsorbs circulating CSF back to peripheral circulation
Arachnoid villi / granulations
What is the rate of reabsorption rate of arachnoid villi?
20 ml/hr
true / false
Rate of production = Rate of absorption
T
Two method of CSF collection.
Lumbar puncture / Spinal tap
Cisternal puncture
Puncture directly below occipital bone
Cisternal puncture
A procedure where needle is inserted into the lumbar subarachnoid space to collect cerebrospinal fluid (CSF) for laboratory testing,
Spinal tap / lumbar puncture
what are the vertebral location for spinal tap?
between the 3rd and 4th or the 4th and 5th lumbar vertebrae
How much CSF is collected in a patient?
20 ml
How many tubes are usually required for CSF collection?
Aseptically collected CSF fluid in 3 or 4 sterile tubes.
Which tube and section is stored at room temp?
Tube 2 - Micro
Which tube is for hema section? what temp?
Tube 3 - ref temp
4th tube for CSF collection is for ?
Optional
Micro - RT
Chem/Sero - Frozen
The first tube for CSF collection is for what section and temp?
Chem/ Sero - frozen
ONLY 1 tube of CSF was collected. What is our priority?
1) MICRO
2) hema
3) chem/sero
CSF volume of adults
90-150ml
Why is the 1st tube for chem/sero?
because chem/sero is least affected by blood or bacteria introduced during CSF collection
why is that the 2nd tube is for microbio?
bec it’s no longer at risk of bacteria/skin contamination due to csf collection
The 3rd tube is for HEMA section. Yes or No? and Why?
Yes, bec it least likely to contain skin cells after spinal tap.
CSF collection for neonates.
10-60ml
What is likely the cause of a hazy/turbid/milky/cloudy csf?
wbcs >200ul
rbcs >400ul
microorganisms
proteins
lipids
What is the most likely cause of a hazy/turbid/milky/cloudy csf?
wbcs >200ul
rbcs >400ul
microorganisms
proteins
lipids
What is the normal csf appearance?
Crystal clear
An abnormal discoloration of csf
Xanthochromia
a yellow csf appearance could be because of ?
1) degradation of oxyhgb to bilirubin
2) increased protein (>150mg/dl)
3) anti-septic contamination with iodine
xanthochromia
a pink csf appearance might be because of ?
the slight amt of oxyhgb
xanthochromia
an orange csf appearance might mean ?
1) Heavy hemolysis
2) hypervitaminosis A - presence of carotene
xanthochromia
an oily csf appearance
Radiographic contrast media
a csf is stored overnight inside ref, it formed an appearance of ?
pellicle - weblike
clinical significance of csf pellicle appearance
turbercular meningitis
a xanthochromia of csf giving red-orange color might be because of?
Rifampicin
a bloody csf appearance could mean that rbcs are?
Increased rbcs >6,000/ul
traumatic tap:
Distribution of blood
Clot formation
Supernatant
Erythrophages
D-dimer
Distribution of blood 1>2>3
Clot formation (+)
Supernatant - clear
Erythrophages (-)
D-dimer (-)
Intracranial Hemorrhage:
Distribution of blood
Clot formation
Supernatant
Erythrophages
D-dimer
Distribution of blood 1=2=3
Clot formation (-)
Supernatant - xanthochromic
Erythrophages (+); presence of hemosiderin and hematoidin crystals
D-dimer (+)