mid exam quistions

questions of mid examination

The main sites for capillary blood collection are
1-
2-
3-
D-negative woman bears a D-positive foetus, the antibody crosses the placenta and attaches itself to the foetal D-positive red cells, causing …………………….

Which choice represents an abnormal value?
A- Basophil percentage 0%
B- Neutrophil percentage 60%
C-Monocytes 12%
D- Lymphocyte 25%
 

By differential WBC count , which cells will increase in following diseases:
a. viral infection
b. allergy
c. Acute bacterial infection
d. chronic bacterial infection
The instruments used in differential WBC count are:
The clinical usefulness of ESR are……………………..& ……………..
The ESR level in anemia ……………………. while in rheumatoid arthritis the ESR level …………………
 
BLEEDING AND COAGULATION TIME
(A)-Bleeding Time :-
Bleeding time is defined as the time taken for a standard skin wound to stop bleeding. Upon vessel injury, platelets adhere and form a hemostatic platelet plug. Bleeding time measures the ability of these platelets to arrest bleeding and therefore measures platelet number and function.
Bleeding time is performed as a screening procedure used to detect both congenital and acquired disorders of platelet function. So the duration of bleeding from standard puncture of the skin is a measure of the function of platelets as well as the integrity of the vessel wall. There are several methods of performing the bleeding time:-
(1)Duke method
(2)IVY method

(1) Duke Method:- Procedure
(a) Clean the lobe of the ear or tip of a finger with alcohol and let dry.
(b) For ear -glass slide is placed behind the ear lobe and held firmly in place. This provided a firm site for incision.
(c)Discard the glass slide if ear lobe has been incised.
(d) Pierce the earlobe (or tip of a finger) with the lancet, making the incision 3mm deep. Start the stopwatch.
(e) Blot the blood with the filter paper at regular 30-seconds intervals. Move the filter paper so that each drop of blood touches a clean area. Do not touch the incision with the filter paper.
(f) When the filter paper no longer shows signs of blood, stop the stopwatch and record the time. Normal values of 1 to 5 minutes.

(2)IVY Method Procedure
(a) Place a blood pressure cuff on the patient s arm above the elbow .Inflate the cuff and maintain pressure at 40 mm Hg .
(b)Cleanse the outer surface of the patient s for arm with alcohol .The area should be free of all superficial veins .
(c)Holding the skin tightly,make three small punctures about 3 mm deep and 1.5 cm apart start the stopwatch.
(d)Blot the blood at regular 3 0-second intervals with the filter paper .Move the filter paper so that each drop of blood touches a clean area. Do not touch any of the incision with the filter paper .

(e)When the filter paper no longer shows signs of blood, stop the stopwatch .
(f) The average of the times for bleeding to stop from the three puncture sites is recorded as the bleeding time. Normal values of 1 to 6 minutes.

B-Coagulation or clotting Time
It’s an indication of the function of clotting factors.
Capillary tube method:- Procedure
(1) Clean your finger with spirit and allow the spirit to dry.
(2) Prick the finger by lancet, remove the first drop of blood.
(3) Squeeze the finger to obtain a large drop of blood, and fill the capillary tube with blood.
(4) The capillary tubes are sealed plasticine and immersed in water bath at 37 c°.
(5) After one minute start breaking small pieces of the capillary tube every 30 second until a fibrin thread is seen between the two broken ends.
(6) By these methods the normal clotting time is 5 to 10 minutes at 37 c°.