blood tests. hematology the study of blood, its functions, and composition blood is composed of 4...

Blood TestsBlood Tests

HematologyHematology

The study of blood, its functions, and composition

Blood is composed of 4 parts◦(1) Plasma Liquid

where the other components are suspended in

◦(2) Red blood cells◦(3) White blood cells◦(4) Platelets

Drawing Blood SpecimensDrawing Blood Specimens

Venipuncture◦Requires puncturing a

vein with a needle and collecting blood into either a tube or syringe

◦Most common sites are the median cubital and cephalic veins of the forearm

3 Methods…

Drawing Blood SpecimensDrawing Blood Specimens(1) Evacuation SystemsEquipment: The VACUTAINER system is used. Including a special double-pointed needle, a plastic needle holder/adapter, and collection tubesCollection tubes are sealed to create a vacuumEasy to collect several samples, tubes collect the exact amount needed, collection tubes are prepared with additives, contamination is reducedMost common

Drawing Blood SpecimensDrawing Blood Specimens(1) Evacuation SystemsThe Vacutainer system

Stopper Colour

Test Types

 Yellow Blood cultures

 Blue Coagulation studies

 RedBlood chemistries, AIDS antibody, viral studies, serologic tests, blood grouping and typing

 Gold or Red/BlackTests requiring blood serum

 Green Electrolyte studies, arterial blood gases

 Lavender Hematology studies

 GrayBlood glucose

Drawing Blood SpecimensDrawing Blood Specimens

(2) Needle and Syringe SystemsFor patients with small or fragile veinsEvacuation system may cause veins to

collapseSmaller needles can be used and

healthcare worker has control over plunger speed

Sample is collected in the syringe and must be transferred to a collection tube

Drawing Blood SpecimensDrawing Blood Specimens(2) Needle and Syringe Systems

Drawing Blood SpecimensDrawing Blood Specimens

(3) Butterfly SystemsAlso for patients with small or fragile veinsEquipment: butterfly needle, tubing, a plastic needle holder/adapter, and collection tubesFlexible wings simplify insertion and the inserted needle remains completely undisturbed while collecting, thereby reducing trauma

Drawing Blood SpecimensDrawing Blood Specimens

(3) Butterfly Systems

What is your blood type?What is your blood type?

Type AType AAntigen A is

present on the surface of red blood cells

Also have antibody B in plasma

Antibody B only binds to antigen B*

Type BType B

Antigen B present on the surface of the red blood cells

Antibody A present in plasma

What happens when Type What happens when Type A is given Type B? A is given Type B?

Results in clumping of RBCs and possible hemolysis - the rupturing of RBCs, which releases hemoglobin

The released hemoglobin can block the renal tubules and cause kidney failure and death

Type ABType AB

Both antigen A and antigen B on surface of RBC’s

Have neither antibody A or B in plasma

Called universal recipients can receive all ABO blood types

Type OType OHave neither

antigen A nor BHowever, they do

have antibody A and antibody B in plasma

Called universal donors blood can give to most people regardless of recipient’s blood type

Blood Type

Rh Factor (Rhesus)

• The Rhesus factor is another antigen on the red blood cell

• It is inherited• Individuals who have this antigen are said

to be Rh positive (85% of Canadians) individuals who do not have this antigen are Rh negative

• Rh negative may donate to Rh positive, but should not receive their blood

Hmmm???