مجموعة من المعيدين (قبل نصف السنة)

Bleeding time

Is the time between the puncture of the skin and the stoppage of blood oozing.
A standardized puncture of the ear lobe is made and the length of bleeding to stop is recorded.
Cessation of bleeding indicates the formation of haemostatic plugs which are in turn dependent on an adequate number of platelets and the ability of the platelets to adhere to the subendothelium to form aggregates.
METHODS:
1-Duke test.
2-Ivy test.
3-Template test.
DUKE TEST:
MATERIAL AND INSTRUMENTS:
1-STERILE DISPOSABLE LANCET.
2-STOPWATCH.
3-CIRCULAR TEST PAPER.
4-ALCOHOL .
PROCEDURE:
1-The earlobe is cleansed with an alcohol sponge and allowed to dry.
2-A typical punctured of the ear lobe is then made using sterile blood lancet .
3-The stopwatch is started at the moment of the puncture.
4-Using circular filter paper the blood is blotted every 30 seconds without allowing the filter paper to touch the wound
5-when bleeding cease , the stopwatch is stopped and the bleeding time = no. of spots / 2 in minutes
Results normal range 1 – 3 minutes




CLOTTING TIME
Is the time required for blood to form aclot in vitro , the basis for the test is that whole blood will form a solid clot when exposed to a foreign surface such as a glass tube .
It is a measure of all intrinsic clotting factors in the absence of tissue factors . Variations are wide and the test sensitivity is limited.
Clotting time was used ascreening test to measure all stages in the intrinsic coagulation system and to moniter heparin therapy.
METHODS
-capillary method
-Slide method
-tube method
TUBE METHOD
1-water bath 37⁰c
2-glass test tube
3-stopwatch
4-plastic syringe and 20 gauge needle
5-fresh whole blood
PROCEDURE
1-lable three glass test tubes with patient name and no. them 1,2,3.
2-perform a clean untraumatic venipuncture using a needle and drawn 4 ml of blood.
3-remove the needle from the syringe and fill each of the three tubes with 1 ml blood .
The last 1 ml of blood may be discarded.Start the stopwatch as soon as the blood enters the syringe.
4-place the three test tubes in a 37⁰c water bath
5-at exactly 5 min remove the first tube from water bath and tilt gently to 45⁰ angle to see whether the blood has clotted.
6-if blood not clotted return it to the water bath and examine it at 30 second intervals .
7-after the blood in the first tube has clotted examine the 2nd tube immediately.
8-then examine the 3rd one .
9-record the time it took the blood in the 3rd test tube to clot.
Normal range 5-12 minutes