Body Fluid Lab Exam (Test #2) Flashcards
(117 cards)
What are the three major types of body fluids?
CSF, synovial and serous
Cerebrospinal fluid is constantly produced where?
Brain choroid plexi (plexuses, capillary knots that protrude into brain ventricles)
The rate of filtration and active transport of cerebrospinal fluid is?
500 mL per Day
What is the blood-brain barrier?
It is the epithelial cell exterior of choroid plexus
Where does CSF flow?
Flows over and around the brain and spinal chord providing cushion for the two.
What are the three major functions of CSF?
Supply nutrients, remove waste & act as mechanical barrier and cushion brain and spinal cord.
How should CSF specimens be treated?
They should be treated with a lot of caution like they are infectious
Where does sterile puncture of spinal cord take place?
Between 3rd & 4th, or 4th & 5th lumbar vertebrae = “lumbar puncture”
What is a ventricular shunt?
A surgically placed tube to drain excess fluid from ventricles. Drainage usually collected in 1 container
Hospitals usually collect 3 tubes from a lumbar puncture sometimes 4. Where do the tubes go start from 1 to 4?
Tube 1 - Chemistry & serology - Contains skin plug but gets centrifuged
Tube 2- Micro - Less likely to have skin flora
Tube 3 - Hematology - Least likely to have skin cell contamination
Tube 4 - Reserved - In case a mistake or more tests are added. No fluids are trashed.
How are CSF tube tests treated?
Treated like they are STAT
How are all the tubes prepared for storage?
Chem & Serology (Tube 1) - Centrifuged and frozen
Micro Tube (2) - Leave at room temp. and set up test ASAP!
Hematology Tube (3) - Refrigerate tube or cell count must be done within 1 hour of collection (normal TAT is 1 hr for fluids).
Reserve (4) - Frozen
After testing on CSF tubes are done, do they get trashed?
No they do not. They are stored for future test addons
Describe a normal CSF in a tube.
Crystal clear and colorless
What could be reasons for a CSF tube to be milky or turbid?
Increased protein, lipids, or WBCs! Turbidity is a definite sign of infectious CSF!
A CSF tube may have hemolysis, what would a scientist need to do to the tube to be sure?
Centrifuge the CSF tube then place the tube in front of a paper white background. The supernatant should be colored compared to the white background!
A CSF tube has a clear pink or red xanthochromia. This suggests…?
OxyHgb due to blood degradation either >2 hrs but <2 days
A CSF tube has a orange xanthochromia. This suggest…?
Heavy hemolysis over 2 hours but under 2 days. It could also suggest carotenemia.
A CSF tube has a yellow xanthochromia. This suggest…?
OxyHgb broken down to unconjugated bilirubin from heavy, long-term (>days) hemolysis or kernicterus.
Kernicterus is…?
Infant brain damage due to increase unconjugated bilirubin
A CSF appearing oily is a sign of…?
Radiographic contrast media administration!
A CSF appearing bloody or hemolyzed is a sign of…?
Recent bleeding (very recent). Reasons of bleeding could be traumatic tap or cerebral hemorrhage.
A CSF appears blood/hemolyzed. How does an MLS differentiate between a traumatic tap or cerebral hemorrhage?
Centrifuge all the CSF tubes (1-4 or 1-3). A traumatic tap will progressively less blood in later tubes. Tube 1 will have the most with Tube 4 or 3 having small / trace amounts. The supernatant may have xanthochromic from serum protein contamination. There CSF sample may be clotted or have bloody streaks.
A cerebral hemorrhage or blood introduced into CSF from a pre-existing cause will have the same amount of blood in all tubes. Other signs are no blood clot and presence of siderophages / erythrophages. The supernatant can be clear if the sample is fresh but xanthochromic will be present if the specimen is old.
Bonus nugget of knowledge! A patient has tubercular meningitis their CSF sample may show…?
Weblike pellicle (scum) to form when refrigerated overnight.