LABORATORY ACTIVITY 10 Flashcards
RBCs is 6-8 um normal diameter, so if we expose blood to water for example are drinking water, our RBCs can take up much water because it has enough surface for the fluid intake, but there are some abnormal RBCs that when we expose it to a very hypotonic solution, the fluid is diluting the cell which results in bursting and we call it [?].
Osmotic Fragile RBC
● We are testing for the ability of the RBC to [?] which will not burst or lysed.
take up fluid
● Demonstrates increased RBC fragility in blood specimens in which the RBCs have decreased surface area to volume ratios.
OSMOTIC FRAGILITY TEST
● So if the RBCs are too small and exposed to [?] just like spherocytes, it will burst or lysed because it is abnormal and has a decreased surface area.
hypotonic solution
PRINCIPLE:
● Blood is added to a series of tubes with increasing [?]. Water enters and leaves the RBCs in each tube until equilibrium is achieved.
● The [?] will follow where the [?] is.
hypotonic NaCl solution
water; salt
● Ex: 0.85% NaCl (Neutral), the fluid within the rbc is also 0.85% NACL.
Imagine if 0.42% NaCl, means it has a low salt content, the fluid within rbc is 0.85%, kapag mas [?] ang surrounding papasok sya sa cell kasi mas maraming salt si cell, and the cell will swell until it lyse, but the normal rbc won`t lyse immediately, but for anything that has decreased surface area it will lysed immediately pagpasok pa lang ng tubig
hypotonic
Testing the fragility of the rbc during hypotonic solutions, if you have hypotonic solution it will go [?] the cells to balance the salt.
inside
INCREASED OF:
LESS RESISTANT
DECREASED OF:
MORE RESISTANT
More Fragile, less resistant to [?] and will burst immediately
hypotonic solutions
Diseases in increased OF:
hemolytic anemia or spherocytes (small rbc`s and very fragile)
[?], Increased OF, less resistant to fluid, easy to hemolyzed
Mature RBC
Less fragile, more resistant to [?]
fluid intake
Diseases in decreased OF:
target cell, thalassemia, liver disease, iron deficiency anemia, sickle cell diease ( bigger surface)
[?], small but decreased OF because they are younger and can tolerate more the fluid
Reticulocyte
PRIMARY FACTOR THAT AFFECT THE OSMOTIC FRAGILITY TEST:
Volume
Surface Area
Shape
Function
PROCEDURE:
Sanford Method
PROCEDURE:
Prepare different concentrations of hypotonic saline using the following procedure:
1. Set up [?] test tubes and label no.[?].
2. Place in each tube [?] (The number of the tube corresponds to the drops of 0.5% NaCI,
3. Using the same dropper, add [?] into each tube until a total of [?] (NaCI & water) are in each tube.
4. Dispense to each tube [?] of [?].
Note: Deliver at the same angle directly to saline solution.
5. Mix tubes and allow to stand at room temperature or centrifuge for [?’].
6. Examine each tube for initial and complete hemolysis.
12; 14 - 25
0.5% NaCI solution
distilled water ; 25 drops
one drop; heparinized or defibrinated blood
1 minute at 2,500 pm
faint pink tinge supernatant with button of intact red cells.
Initial Hemolysis
Usually happens at tube 22
Initial Hemolysis
homogenous red mixture without sediment.
Complete Hemolysis
Usually happens at tube 17
Complete Hemolysis
To determine the % concentration of NaCl solution where initial and complete hemolysis occurred
For example: Since complete hemolysis happened in tube 17. To know the % concentration of NaCl in tube 17, the tube number which is 17 is multiplied by 0.02. That is
0.34%.
This test measures the ability of the RBCs to take in fluid without lysing.
OSMOTIC FRAGILITY TEST (OFT)
It reflects the shape and size of
erythrocytes (?).
specifically the surface area-to-volume ratio
Cells with (?) have a limited capacity to expand in hypotonic solutions and therefore lyse even at a less hypotonic
concentration of saline than the normal biconcave cells.
decreased surface area-to-volume ratio
OSMOTIC FRAGILITY TEST (OFT) Specimen Required:
Heparinized or defibrinated blood
OSMOTIC FRAGILITY TEST (OFT)
PROCEDURE:
Sanford Method
