LABS FOR NEURO DISEASES Flashcards
If the pressure proves to be very high-over____________—one should
obtain the smallest necessary sample of fluid and then,
according to the suspected disease and patient’s condition, administer mannitol or another hyperosmolar agent
400 mm HG
Dexamethasone or an equivalent corticosteroid may
generally also be given in an ___________ in order
to produce a sustained reduction in intracranial pressure
initial intravenous dose of
10 mg, followed by doses of 4 to 6 mg every 6 h
When in cisternal puncture indicated?
spinal block requiring a sample of
cisternal fluid or for myelography above the lesion.
Warming of the analgesic
by rolling the vial between the palms seems to diminish
the _______
burning sensation that accompanies cutaneous
infiltration.
The puncture is usually
easiest to perform at the L3-L4 interspace, which corresponds
in many individuals to the________
axial plane of the
iliac crests, or at the interspace above or below
______ during the insertion of
the needle indicates that it is placed too far laterally
Sciatic pain
L P has few serious complications . The most common
is _______, estimated to occur in one-third of
patients, but in severe form in far fewer.
headache
The pain is presumably the result of a _____________ from leakage of fluid at the puncture site and _____________as the patient assumes the erect posture.
reduction of CSF pressure
tugging on cerebral and dural vessels
Bleeding into the spinal meningeal or epidural
spaces after lumbar puncture can occur in patients who
are taking anticoagulants (generally with an international
normalized ratio _________, or impaired platelet function (alcoholism,
uremia) .
[INR] > 1 .4), have low platelet counts
<50,000/mm3
In the normal adult,
the opening pressure varies from ________
100 to 180 mm Hp, or
8 to 14 mm Hg
In an adult, a pressure of
________ indicates intracranial hypotension,
generally caused by leakage of spinal fluid or systemic
dehydration.
50 mm H20 or below
The presence of a spinal subarachnoid block was
in the past confirmed by jugular venous compression
_____________
(Queckenstedt test, which tests for a rapid rise in CSF pressure within a few seconds after application of the pressure on the vein).
The presence of red blood
cells imparts a hazy or ground-glass appearance; at least
________
must be present to detect this change.
The presence of
______________, depending on the amount of blood;
centrifugation of the fluid or allowing it to stand causes
sedimentation of the RBCs
200 red blood cells (RBCs) per cubic millimeter (mm3)
1,000 to 6,000 RBCs per cubic millimeter imparts a hazy
pink to red color
In subarachnoid hemorrhage, the
RBCs begin to hemolyze within a few hours, imparting
a pink-red discoloration _______
(erythrochromia) to the
supernatant fluid;
only with large amounts of venous
blood (RBC more than 100,000/mm3) will the supernatant
fluid be faintly xanthochromic due to__________
contamination
with serum bilirubin and lipochromes
The pigments that discolor the CSF following subarachnoid
hemorrhage are __________
oxyhemoglobin, bilirubin,
and methemoglobin
Oxyhemoglobin
appears within several hours of hemorrhage, becomes
maximal in approximately ________, and diminishes over
a _______
36 h
7- to 9-day period.
Bilirubin begins to appear in___________ and increases in amount as the oxyhemoglobin
decreases.
2 to
3 days
___________
(through hemoglobin breakdown products, particularly
oxyhemoglobin) also impart a yellow tint to the CSF, as
do blood clots in the subdural or epidural space of the
cranium or spinal column
Hypercarotenemia and hemoglobinemia
_________does not enter the
CSF because a low renal threshold for this pigment permits
rapid clearing from the blood
Myoglobin
During the first month of life, the CSF may contain a s mall
number of _________
mononuclear cells
The protein content of CSF from the basal cisterns is _______and that from the ventricles is ______
10 to 25 mg/ dL
5 to 15 mg/ dL.
In children, the protein concentration is somewhat
lower at each level ______
( <20 mg/ dL in the lumbar subarachnoid space).
If the serum protein concentrations
are normal, the CSF protein should increase by about __________RBCs provided that the same tube of CSF is
used in determining the cell count and protein content
1mg per 1,000
Values in the lumbar CSF of 1,000 mg/ dL or
more usually indicate a block to CSF flow; the fluid is then
deeply yellow and clots readily because of the presence of fibrinogen; a combination called _______
Froin syndrome
The gamma globulin fraction
in CSF is approximately _______ of that in serum.
70 percent