This document discusses blood collection methods. It describes the three main types of blood collection: venous, capillary, and arterial. Venous blood collection is the most common, involving puncturing a vein with a needle and collecting blood into a tube or syringe. Capillary collection involves a small skin puncture to obtain a small blood sample, while arterial collection is rarely needed and involves puncturing an artery. The document outlines the equipment, procedures, and safety measures for performing venipuncture. It also discusses different types of blood collection tubes and their uses based on the additive used.

1. Dr.K.Sudha Rameshwari,M.Sc., M.Phil., D.Litt
Assistant Professor,
Department of Biochemistry,
V.V.Vanniaperumal College for Women,
Virudhunagar, Tamilnadu, India

2.  Blood is a suspension of cells- erythrocytes,
leucocytes and thrombocytes in fluid, plasma.
 The cellular fraction constitutes 45% of the
volume of blood.
 Chemically, blood is a very complex fluid
containing a large variety of substances.
Collection of blood:
Blood collection is three types.
1. Venous blood collection
2. capillary blood collection and
3. Arterial blood collection

3.  The volume of blood obtained by
venipunture is sufficient to carry
out multiple tests.
 Venipuncture is also called
phlebotomy, a superficial vein is
punctured with a hypodermic
needle and blood is collected into a
syringe or tube.
 Venipuncture can be done by
syringe method or vaccum tube
method.
 The latter is not very popular.

4.  Container for blood collection
 A needle
 Syringe
 Tourniquet
 Disinfectant
 Swab
 Tray of cold water to rinse needle
and syringe after drawing blood.

5.  Needles of 20-22 gauge
(diameter) are used for
routine Venipuncture.
(The higher the gauge,
the smaller the needle
diameter).
 Larger diameter needles
are required for
collecting blood donor
units.
 Needle should be
sterilized.
 Syringe: 2ml, 5ml,10ml
and 20ml

6. This is a soft rubber tubing of 2-
5mm bore and 30-40cm in length.
 A flat elastic strip can also be used.
This tourniquet is used to make the
veins more prominent.
It must be applied on the skin
before the puncture is made.
Methylated spirit or 70% alcohol is
put in a swab which is rubbed on
the skin before the venipuncture.
The alcohol should dry out before
the puncture is made.
Tray of cold water
•The cold water helps to haemolyse the red cells and make it easy to clean the
syringe.
•Now disposable syringes are used.

7. Artery – a blood vessel that carries
oxygenated blood from the heart to the
tissues.
Vein - a blood vessel that carries
deoxygenated blood from the tissues to
the heart
Capillary- a minute blood vessel that
connects the smallest arteries to the
smallest veins and serves as an
exchange vessel.

8. VENOUS BLOOD COLLECTION
•Venous blood is collected usually from
the antecubital vein or some other
prominent vein on the forearm.
• The patient is seated comfortably and
asked to extend his arm.
• A tourniquet is tied firmly around the
upper arm. A suitable vein is selected
and the skin over it sterilized by
rubbing spirit over it with a pad of
cotton wool.
•A sterile hypodermic needle attached to
a syringe is introduced into the vein and
the tourniquet removed.
•The desired amount of blood is drawn
into the syringe by gently withdrawing
the plunger.
•A pad of cotton wool soaked in spirit is
placed on the skin whereas the needle
was introduced and the needle is
withdrawn.
•The blood is transferred into a suitable
container after removing the needle
from the syringe.

9. Capillary blood collection
•A capillary is a small blood vessel connecting small
arteries to small veins.
•The capillary blood is obtained by skin puncture.
•It provides only small quantities of blood specimens for
making blood smear.
•In adults and older children the tip of the finger is
punctured and in infants the heel is chosen.
•The middle finger or ring finger of the left hand is usually
chosen for skin puncture.
•The site is cleaned with cotton wool swab dipped in 70%
alcohol. A quick puncture is made with a sterilized lancet.
•The puncture sterilized lancet.
•The puncture should be 2-3mm deep.
• The lancet should be discarded. The first drop of blood
is wiped away. The succeeding drops are used for tests.
•The specimen is collected by holding a capillary tube to
the blood drop or by sucking into sahli pipette for
hemoglobin determination and for blood count or
touching the drop to the glass slide for preparing smear.
Uses: Hemoglobin, hematocrit, blood glucose,
prothrombin time

10.  Arterial blood is
required rarely.
This may be
collected from
the radial,
brachial or
femoral artery.
 It is used for
estimation of
blood gases.

12. Red and yellow Top
Plain (without anticoagulant)
 Serum
Uses
 All chemistry test
 Hormones
 Serology and virology

13. EDTA anticoagulant
 Plasma
Uses
 CBC
 Blood film
 ABO grouping
 Malarial test
 HA1C
 Cross matching
 HB electrophoresis
 Sickle cell test

14. Light blue top
 Sodium citrate 1:9 (anticoagulant)
 Plasma
uses:
 PT(prothrombin time)
 PTT(partial prothrombin time)
Green top
Heparin-Plasma
Uses
 Chemistry test
 Beta HCH (hormone)

15. Black Top
 Sodium citrate (1:4)
 Plasma
Uses
 ESR
Gray Top
 Fluoride and oxalate
 Plasma
Uses
 Glucose (especially when testing will be
delayed)
 Blood alcohol

17.  https://www.youtube.com/watch?v=NS68ePy
kav0&feature=youtu.be
 https://www.youtube.com/watch?v=dKenI4Q
2pWE

18. Serum
 The clear liquid that can be separated from clotted blood.
 If blood is allowed to stand, it coagulates in a few minutes. After
sometime, a clear, straw colored fluid known as serum. The
separation by centrifuging the clotted blood.
Plasma:
 Clotting may be prevented by treating blood with certain
anticoagulant by centrifuging such blood, cells and plasma can
be separated.
 The liquid part of the blood and lymphatic fluid, which makes up
about half of the volume of blood.
 Plasma is devoid of cells and, unlike serum, has not clotted.
 Blood plasma contains antibodies and other proteins.
 It is taken from donors and made into medications for a variety of
blood-related conditions.
Terms:
 Plasma = blood – cells
 Serum = blood – cells and clotting factors
Serum differs from plasma:
 The liquid portion of normal unclotted blood containing the red
and white cells and platelets.
 It is the clot that makes the difference between serum and
plasma.

19.  Kanai L Mukherjee & Swarajit Ghosh (2010). Medical Laboratory Technology,
New Delhi:Vol I, Tata McGraw Hill, 2nd Edition.
 https://slideplayer.com/slide/10569247/
 https://www.medicinenet.com/serum/definition.htm
 https://www.medicinenet.com/plasma/definition.htm
Images:
 https://www2.slideshare.net/DrShahidaBaloch1/vacutainer-and-
anticoagulant-ss
 https://acutecaretesting.org/en/articles/blood-gas-testing-and-related-
measurements-national-recommendations-on-behalf-of-the-croatian
 https://www2.slideshare.net/HusseinAltameemi2/blood-sample-collection-
186422031
 https://www.nclexquiz.com/blog/types-needles-injection-needle-gauges-
injections-size-chart/