(M) Week 8: CBC and other procedures II part 1 Flashcards
hemoglobin is the red iron-bearing protein contained within the ________________ in the normal blood
erythrocytes
this can carry oxygen to and carbon dioxide from the tissues
hemoglobin
Measuring the level of the hemoglobin concentration determines the ___________________ of the person’s blood
oxygen carrying capacity
the clinical use of hgb determination is the same as hct determination which is to diagnose __________ and ____________-
anemia and polycythemia
familiarize the four methods of hgb determination
- copper sulfate / specific gravity method
- Gasometric method (oxygen capacity method)
- chemical method (iron content method) e.g. Wong’s method
- colorimetric methods
what is the specific gravity of copper sulfate used in the specific gravity method
1.052 and 1.054
copper sulfate / specific gravity method
If the drop of blood shrinks, hgb level is (acceptable/unacceptable)
acceptable
indicates hgb level is greater pr equal to 12 g/dl
copper sulfate / specific gravity method
If the drop of blood floats, hgb level is (acceptable/unacceptable)
unacceptable
indicates hgb level is below 12 g/dl
What is the principle of copper sulfate method
specific gravity of blood against copper sulfate solution
What is the principle of gasometric method / oxygen capacity method
oxygen capacity of hemoglobin is being determined
What tool is used to measure the amount of oxygen in the gasometric method?
Van Slyke manometric apparatus
how many ml is one gram of hemoglobin?
oxygen
1.34
Gasometric method:
What reagent is used to lyse the blood and release its oxygen
saponin
What is the principle of the chemical method
iron content of hemoglobin is determined
how many percent is the iron content of 1 hgb
0.347% or3.47
what is the formula to compute for the hemoglobin concentration in the blood
iron content (in mg/dl) / 3.47
What are the two types of colorimetric method
- visual / direct methods
- indirect methods
What are the tests under direct / visual matching methods
- Talquist scale
- hemoglobinometer
- acid hematin
- alkali hematin
What are the tests under indirect methods
- Oxyhemoglobin
- carboxyhemoglobin
match the principle to the method:
based on color comparison between the color of blood in the absorbent paper and color in the color chart
a. alkali hematin
b. hemoglobinometer
c. talquist scale
d. acid hematin
c
Talquist scale manner of reporting
4.7 to 9.4 grams
actual anemia
Talquist scale manner of reporting
10.9 to 12.5 grams
Suggestive Anemia
Talquist scale manner of reporting
14.1 to 15.6 gram
normal
what is the percentage error in talquist scale
30-50%
the principle of the dare hemoglobinometer is similar with ____________
refractometer
what is the percent error of the dare hemoglobinometer?
20-30%
match the principle to the method:
Lysis of red blood cell using acid reagent
(e.g. HCl) to liberate hemoglobin, which then
converts to methemoglobin, which is what is
measured in this method
a. alkali hematin
b. hemoglobinometer
c. talquist scale
d. acid hematin
d.
familiarize the pipetts used for acid hematin
Sahli’s Hellige (20 uL capacity) most common
Haden-Hausser
Sahli-Adams
Haldane
Newcomer
Osgood
what is the reagent used for acid hematin?
0.1 N HCl
in acid hematin, hemoglobin is converted to ___________________ using 0.1 N HCl
methemoglobin
acid hematin is verified uing what method?
cyanmethemoglobin
this direct method lyses with heat and uses NaOH as the reagent
Alkali Hematin
Oxymethemoglobin:
a photometric determination of hemoglobin done by measuring oxyhemoglobin
Sodium carbonate
Gasometric
T or F
Sodium carbonate is simple and quick, easily creates a stable HbO2 standard
F (no possibility of preparing a stable HbO2 standard)
Oxyhemoglobin test
A pulse oxygen saturation and pulse rate can be measured through the finger using a ____________________ monitor
photoelectric oxyhemoglobin
photoelectric oxyhemoglobin monitor is observed in what tool in the hospital
pulse oximeter
A test performed only when carbon monoxide poisoning is suspected
carboxyhemoglobin test
There should be a (high / low) carboxyhemoglobin concentration in the blood for normal individuals
low
When Carbon monoxide accumulates in our
blood, It has an increased affinity to
hemoglobin, about _______ times than oxgen
500
heavy smokers have a (higher / lower) RBC count due to carboxyhemoglobin
higher
This method measures the amount of oxygen using a Van Slyke manometric apparatus. The level of hemoglobin is determined by computation
Gasometric method
this is also known as the hemoglobincyanide method
Cyanmethemoglobin method
T o F
hemoglobin cyanide method can only be done manually
F (manually and automatically)
what is the reference method for hemoglobin determination
Cyanide hemoglobin
What solution is used for cyanmethemoglobin?
drabkin’s solution
Drabkin’s soluion is made out of
potassium cyanide
potassium ferricyanide
sodium bicarbonate
Exposure to _________ deteriorates the Drabkin’s regent, causing a false _____________ in the hemoglobin values
light, decrease
What is the buffer solution in modified drabkin
dihydrogen potassium phosphate
What is the buffer in the original drabkin?
sodium bicarbonate
For cyanmethemoglobin
what is combined with hemoglobin to convert into methemoglobin
potassium ferricyanide
What apparatus is needed to record the cyanmethemoglobin?
spectrophotometer
at what wavelength is cyanmethemoglobin read?
540nm
All forms of hemoglobin may be measured using the cyanmethemoglobin method except
sulfhemoglobin
what anticoagulant is used for samples that will udergo the cyanmethemoglobin method
EDTA
what is the pH of the drabkin’s solution used in the cyanmethemoglobin method
7.0-7.4
what is the formula for the cyanmethemoglobin method
c test / c standard = a test / a standard
cyanmethemoglobin method reference values:
men
140-180 g/L
cyanmethemoglobin method reference values
women
120-160 g/L
cyanmethemoglobin method reference values
women in late pregnancy
85-140 g/L
cyanmethemoglobin method reference values
newborn
150-200 g/L
Minimum hemoglobin requirement of a potentional
blood donor:
o Men – At least _________
o Women – At least _________
o Men – At least 13.0 g/dL
o Women – At least 12.5
Clinical significance (Increased / Decreased)
(hyperchromia) in polycythemia, dehydration, in poorly
compensated heart disease with cyanosis, and in changing from high to low
altitude.
increased
Clinical significance (Increased / Decreased)
oligochromia
decreased
the presence of free hemoglobin in the blood plasma
hemoglobinemia
What condition is commonly seen in cases of:
1. severe infection
2. sever burns and frost bite
3. poisoning with potassium chlorate and mushrooms
4. paroxysmal hemoglobinuria
5. hemolytic transfusion reactions
hemoglobinemia
Sources of error
- cyanmethemoglobin is sensitive to ______
light
cyanmethemoglobin storing conditions
in a dark amber bottle and store inside the cabinet
high _______ , _________, and _________ can cause turbidity and falsely elevated results in the cyanmethemoglobin method
WBC, Platlets, and lipemia
Difference beween chylomicrons and VLDL
these are the floating particles that occurs on plasma/serum let to stand on room temp or ref temp
chylomicrons
Difference beween chylomicrons and VLDL
Ifthere are no floating particles or turbidity on a plasma/serum that was left to stand it is ____
VLDL
this is the volume of packed RBCs that occupies a given volume of whole blood
hematocrit
hematocrit is also kown as
packed cell volume (PCV)
hematocrit is reported as __________ or _________
percentage or liters per liter
if the hematocrit is represented in decimal form, the appropriate unit is
liter per liter (conventional unit)
what is the standard RPM of the microhematocrit centrifuge
10k to 12k
Hematocrit determination is used to diagnose ___________ or ___________
anemia or polycythemia
T or F
Hct is higher in adults compared to children
F (children higher)
individuals living in high altitude places have (high / low) HCT value
high
smokers have (high/low) HCT values due to the presence of carboxyhemoglobin in their blood
high
macro vs micro method of hct determination
method of blood collection
macro: venipuncture
micro: skin puncture
macro vs micro method of hct determination
amount of blood
macro: larger
micro: smaller
macro vs micro method of hct determination
relative centrifugal force
macro: 2,000 to 2,300 g
micro: 10,000 to 12,000 g
macro vs micro method of hct determination
time of centrifugation
macro: longer , around 30 minutes
micro: shorter, 4-5 minutes
macro vs micro method of hct determination
simplicity of technique:
macro: not simple
micro: simple
macro vs micro method of hct determination
ESR
Macro: cannot be performed in the wintrobe tube
Micro: cannot be performed
macro vs micro method of hct determination
spilling / leakage
macro: not common
micro: common
macro vs micro method of hct determination
breakage of buffy coat
macro: not common
micro: common
macro vs micro method of hct determination
separation of buffy coat
macro: complete
micro: not complete
macro vs micro method of hct determination
cost of apparatus
macro: expensive
micro: cheaper
familiarize the clinical significance of hct determination
- It gives a rough estimate of the size or erythrocytes and the
concentration of erythrocytes but not the whole red cell mass. - It is used in the calculation of the blood indices.
- The buffy coat obtained from the hematocrit tube has numerous uses.
- Hematocrit is a good simple screening test for anemia.
- Since the inherent error obtained in hematocrit is less as compared to
erythrocyte count
What are the macromethods of hct determinatin
- Wintrobe Method
- Haden’s Modification
- Van Allen Method
- Sanford-Magath
- Bray’s
what is the anticoagulant used in the wintrobe method
double oxalate
The Wintrobe tube is filled up to what mark?
10 cm
oxalated blood in wintrobe tube avoids ________
bubble formation
Wintrobe method:
the wintrobe tube is centrifuged at 2500 rpm for ________ minutes
30
Wintrobe method:
What are observed after centrifugation
fatty layer
plasma layer
buffy coat layer
PCV layer
Macromethods of hematocrit determination
what is the anticoagulant of choice in Haden’s modification
1.1% sodium oxalate
Macromethods of hematocrit determination
what is the anticoagulant of choice in the Van Allen method
1.6 sodium oxalate in distilled water
What is the anticoagulant of choice in sanford-magath
1.3% sodium oxalate
what is the anticoagulant of choice for Bray’s method
heparin
What is the preferred anticoagulant for Adam’s micromethod
heparinized capillary hematocrit tube
normal hematocrit value for men
40-55%`
normal hematocrit value for women
36-48%
normal hematocrit value for newborns
45-60%
increase or decrease in hematocrit:
improper sealing of the capillary tube
decreased
increase or decrease in hematocrit:
insufficient centrifugation
increased
increase or decrease in hematocrit:
increased concentration of anticoagulant
decrease
increase or decrease in hematocrit:
delay in reading results
increase
increase or decrease in hematocrit:
after blood loss
decreased
increase or decrease in hematocrit:
buffy coat should not be included in reading
increased
increase or decrease in hematocrit:
tissue juice contamination during capillary puncture
decreased
increase or decrease in hematocrit:
dehydration
increased
what is the formula for MCV
hct x 10 / RBC count
what is the formula for MCH
hgb x 10 / rbc count
what is the formula for MCHC
hgb x 100 / hct
rule of three only applies to speciments that have
normocytic normochromic RBCs
what is the rule of three
hgb x 3 = hct ± 3
this measures the degree of anisocytosis
indicates how varied the rbcs are in terms of size and volume
red blood cell distribution width
these are young RBCs which are formed when the nucleus of the late normoblasts are lost through extrusion
reticulocyte
used as an index of bone marrow activity, rbc production, and to monitor therapeutic measures for anemia
reticulocyte count
what is the staining of rbcs in the dry method of reticulocyte count
gray-blue
what is found in the the staining of reticulocytes in the dry method of reticulocyte count
deep blue filamentous web or granules within the cells
Any cell that contains two or more particles of __________-stained materials is classified as a reticulocyte
blue
Dry method
Count the reticulocytes seen in ___ successive fields of vision or while enumerating 1000 mature RBCs
10
what is the computation for the reticulocyte %
Reticulocyte % = reticulocyte counted x 100 / 1000
inserted in the eyepiece of the microscope which allows rapid estimations of large number of red cells by imposing two squares (one square is nine times the area of the other
square) onto the field of view
miller disk
reticulocytes are counted in the large square and red cells in the small square in successive microscopic fields until at least _____ cells are counted
300
Dry or wet method?
new methylene blue
Cook
Mayer
Tureen
Seiverd’s
dry
what is the normal value of of MCHC
31-37%
what is the normal reticulocyte range in adults
0.5-1.5%
what is the normal reticulocyte range in newborns
2-6%
what is the normal reticulocyte number of concentration
25,000 - 75,000 /mm3 or uL
25-75 x 10^9 / L