This document describes an experiment involving determination of clotting time and bleeding time, calculation of red blood cell indices, and blood typing. It provides objectives, materials, procedures, and results for measuring clotting time and bleeding time using a lancet and timer. Formulas and procedures are given for calculating mean corpuscular volume, hemoglobin, and hemoglobin concentration from hematology results. Finally, the process for blood typing using anti-A, anti-B, and anti-Rh sera on a slide is outlined, along with examples of blood type compatibility. Discussion questions relate to the clinical significance of test results and concepts of blood typing.

1. EXPERIMENT III
Clotting Time and Bleeding
Time
RBC Indices Determination
Blood Typing
GROUP 2
NAME

2. OBJECTIVES:
Perform bleeding and clotting time.
Correlate the RBC Indices such as MCV, MCH, and MCHC with the RBC count.
Determine blood types.
CLOTTING TIME AND BLEEDING TIME
MATERIALS:
1. Lancet, cotton ball with alcohol
2. Slide for clotting time
3. Pin or matchstick
4. Absorbent paper for bleeding time
5. Timer
SPECIFIC PROCEDURE:
A. PRICK FINGER
- to obtain blood samples for both bleeding and clotting time.
B. BLEEDING TIME
Note the time when the prick was done and mark this as time zero.
Blot a drop of blood from the puncture site with absorbent paper without touching the skin.
Repeat every 30 seconds until no more blood stain forms on the absorbent paper.
Note the time and subtract time zero. This is the bleeding time (the time it took for the bleeding to stop).

3. C. CLOTTING TIME
1.Drop the globule of blood onto the slide (be
careful not to touch the slide directly) (this is for
clotting time).
2.With the tip of a pin or a matchstick, very
carefully lift the pin/matchstick vertically from the
globule of blood to see if any thread-like strand
goes with it.
3.Repeat (procedure 2) at 30-second intervals until
thread-like strands are seen (check Figure 1).
Note the time and subtract time zero. This is the
clotting time (the time it takes for blood to form a
clot).
RESULTS:
Bleeding time: 210sec
Clotting time: 8mins 30sec

4. GUIDE QUESTIONS:
1.What do bleeding time and clotting time measure? Give the clinical significance of each
parameter.
- Both are qualitative measurements. The bleeding time it takes for the bleeding to stop. It
is used for screening problems in primary hemostasis. Clotting measures the ability of
blood to clot and is used for assessing secondary hemostasis.
2.What do PT and APTT measure? Give its clinical significance.
- Both are used to evaluate coagulation disorder. PT assesses Extrinsic and Common
Pathway and is the test of choice to monitor warfarin therapy. APTT assesses Intrinsic and
Common Pathway and is the test of choice to monitor heparin therapy.

5. CASE #1:
Mrs. Garcia consulted her dentist about her son, Juan aged 3. He had lost
a front tooth in a playground collision at his preschool and the wound had
continued oozing blood during the night after the accident. The bleeding
had stopped when the dentist saw Liam the next morning but he noted that
the hemostatic plug appeared soft and friable. The bleeding started again
the evening after the visit to the dentist and continued intermittently for
three days. The boy was then seen by their family doctor who arranged for
a series of laboratory tests.

6. Apart from a raw area in the gum at
the site of the missing upper left first
incisor and the soft,
friable hemostatic plug, nothing
abnormal was found on examination.
A laboratory test was done and the
results are shown.
LAB TEST VARIABLE VALUE
REFERENCE
RANGE
Blood screen RBC count x 10
12
4.6 4.2 – 6.2
Hemoglobin (g/L) 142 135 – 165
Hematocrit 0.46 0.4 – 0.5
Additional blood tests Platelet count x 10
9
360 140 – 400
Bleeding time (min) (Ivy method) 2 1 – 4
Partial thromboplastin time (s) 55 25 – 40
Prothrombin time (s) 12 10 - 13
Factor VIII (%) 5 50 – 200

7. DISCUSSION QUESTIONS:
1. Which step of the hemostasis is likely affected in our patient? Explain your answer.
- The patient most likely have a problem in secondary hemostasis, particularly in the
intrinsic pathway. This is based on the blood test results showing a deficiency in FVIII
and a prolonged PTT. Factor VIII, together with FIX and calcium makes up the intrinsic
tenase complex that will activate FX. If there is a deficiency in FVIII, the formation of a
stable clot will be hindered.
2. How do the two terms “hemostasis” and “coagulation” differ? Define their terms
-Hemostasis refers to the cessation of bleeding that has end goal formation of platelet
plug and fibrin clot formation which is the more stable form of plug. Coagulation refers
to the cascade of activation of clotting factors subsequent to primary formation of
platelet plug, to further stabilize it or to form a stable fibrin clot.
3. Is hemostasis considered positive or negative feedback? Why?
- Circulating thrombin is the primary culprit because it activates platelets, activates
coagulation proteins (positive feedback loops within the coagulation cascade), and
catalyzes fibrin formation, of which the ensuing clots consume control proteins.

8. II. RBC INDICES (MCV, MCH, MCHC)
DETERMINATION
RBC INDICES (MCV, MCH, MCHC)
DETERMINATION
Formula:
Mean Cell Volume (MCV) = (Hematocrit
X 10)/(RBC count X 106) fL
Mean Cell Hgb (MCH) = (Hgb X 10)/(
RBC count X 106) pg
Mean Cell Hgb Concentration =
(HgbX100)/Hct

9. CASE #2:
Mrs. Reyes, a 25-year-old female, consulted at the outpatient clinic
due to dizziness and easy fatigability these past two weeks. She is
pregnant with her first child, currently in the 24th week of gestation.
Her dietary habits have not changed from her pre-pregnancy state,
but she claims she craves ice cubes several times a day. She is never
fond of eating red meat and green leafy vegetables and has not taken
any food supplements despite the recommendations during her last
prenatal checkup.

10. Physical examination shows
generalized pallor, notably her
palms and palpebral
conjunctivae (i.e. the inner
surface of her eyelids). Her
heart rate was also faster than
normal (A heart rate of 110
beats per minute). Her doctor
ordered a complete blood count
which is shown:
Lab test Value Reference range
RBC count x 10
12
3.5 4.2 – 6.2
Hemoglobin (g/L) 85 135 – 165
Hematocrit 0.27 0.4 – 0.5
MCV X X
MCH X X
MCHC X X
WBC count x 10
9
8.5 5.0 – 10.0
Neutrophil 55 40-60
Lymphocyte 30 20-35
Monocyte 10 4-10
Eosinophil 4 1-4
Basophil 1 0-1
Platelet count x 10
9
290 150-450

11. 1.Based on her history and physical examination,
what could be the problem with Mrs. Reyes's
medical condition?
- Mrs. Reyes have an Iron Deficiency Anemia.
During pregnancy, the demand for iron intake
increases. This can be obtained from red meats,
green leafy vegetables, and iron supplements.
However, the diet of patient does not include
those. In addition to that, pica or craving of non-
food items like ice is one of the unique
characteristics of IDA.
2.What do MCV, MCH, and MCHC measure, respectively? Provide also the
normal values.
- MCV it is an indicator of the average/mean volume of erythrocytes
(RBCs).
MCH it is an indicator of the average weight of
hemoglobin in individual RBCs.
MCHC it is a measure of the average concentration of hemoglobin in
grams per deciliter.
MCV fL 80–100
MCH pg 26–34
MCHC g/dL 32–36
DISCUSSION QUESTIONS:
3.Given the formula above, determine the RBC indices of Mrs. Reyes and
their clinical significance.
MCV 77.14
MCH 24.28
MCHC 31.48

12. III. BLOOD TYPING
MATERIALS:
Slide - for blood typing typing (individual).
Matchsticks, pipette
Blood typing sera (provided)
BLOOD TYPING – ABO AND RH TYPING
(INDIVIDUALLY DONE)
On the slide, place one drop of antiserum A in one
end, a drop of antiserum B in the other end, and anti-
Rh in the middle of the slide.
Add 1-2 drops of your blood to each anti-serum.
Mix with a matchstick and observe for 5-20 minutes
for any agglutination reaction (Be sure NOT to use the
same end of the matchstick per concavity).
RESULTS:
Blood Typing:
Antiserum A plus your RBC = _______
Antiserum B plus your RBC = _______
Anti Rh plus your RBC = ________
Therefore, your blood type is _______

13. DISCUSSION QUESTIONS:
1. Situation: If your blood type is A+, is it okay to donate
your blood to a patient who has a blood type AB+? Why or
why not?
- A+ and AB+ blood type are compatible hence, A
person who has a blood type A+ can definitely donate
a blood to a patient with blood type AB+ because AB+
are generally universal recipient, and blood type A+
contains and Rh which is present in AB recipient
2. What will happen if the wrong blood type is transfused to
a patient? State your answers in 5 sentences only.
- the body will recognize the wrong blood as foreign
since it is incompatible and will trigger the immune
system to attack the transfused blood leading to life-
threatening reactions
3. The blood type of Francis is O, while both of
his parents are blood type A. Is this possible?
Explain your answer.
- Yes, This may only happen if the genotype
of both parents is heterozygous alleles AO.
This be visualized using a Punnett square,
Therefore, there is 25% chance

15. THANKYOU
AND
GODBLESS