Blood collection and analysis is one of the most important diagnostic procedures available to clinicians within healthcare. Its data is relied upon in the clinical setting for the interpretation of pathological signs and symptoms.

Phlebotomy for Blood Collection

The surgical opening or puncture of a vein to withdraw blood or to introduce fluid is called phlebotomy. The person who performs phlebotomy is called a phlebotomist, doctor, nurse & medical laboratory scientist.

Requirements for Blood Collection

Syringes and needles
Tourniquet
Specimen containers (or evacuated tube system) – plain and with various anticoagulants
Request form
70% isopropanol swabs and cellulose pads
Adhesive dressings
Self-sealing plastic bags
Rack to hold specimen upright during the process of filling
A puncture-resistant disposal container should also be available

NEEDLES should not be too fine/ too large/ too long
Vary from large (16 G) to small (23 G)
For adults – 19 or 21 G suitable
For children- 23 G
Ideally should have a short shaft (15mm)
Butterfly needles- when blood has to be collected from a very small vein
Come in 21, 23, and 25 G

Blood can be collected from 3 different sources

Capillary
Artery
Vein

Venipuncture:

Venipuncture involves puncturing with a needle and collecting blood in a syringe or evacuated tube. Venipuncture is a routine and common procedure done to collect venous blood directly from the vein.

It is performed using the antecubital fossa, a vein of the wrist, the dorsum of the hand or foot, or other accessible location.

The best site for blood collection is: Ante-cubital fossa

In order to do this safely, the phlebotomist must have a basic understanding of the following:

Anatomy
The criteria for choosing a vein
The device used
Skin preparation
Personal safety – infection control policy

Most common sites for Venipuncture – Blood collection

Median cubital vein

Dorsal Venous Network

Venous Puncture Technique for Blood Collection

Procedure:

Verify computer-printed labels match requisitions
Check patient identification band against labels and requisition forms
Ask the patient for his/her demographics
Position patient properly
Assemble equipment and supplies
Apply a tourniquet on the upper arm and ask to make a fist
Select a suitable vein for puncture
Put on gloves
Cleanse the site
Enter skin with needle at 30-degree angle/ < to arm with bevel up of the needle

Follow the geography of the vein and insert the needle smooth
Using a syringe, pull back on the barrel with a slow, even tension as blood flows into the syringe
Release the tourniquet when blood begins to flow.
Never withdraw the needle without releasing the tourniquet

Precautions in Blood Collection:

The area must be cleaned/appropriately sterilized.
The tourniquet should not be applied for a long time.
Blind attempts should not be made.
Once the needle is withdrawn pressure should be applied and maintained for 1-2 minutes, if not can cause ECCHYMOSES.

POST-PHLEBOTOMY PROCEDURE

Recheck the patient’s details and make sure it corresponds to the information on the request form
Each submitted specimen must be labeled with the patient’s Demographics (written exactly as it appears on the Test Request Form) and the tests to be conducted
Patient demographics include – Patient name, sex, age, DOB, DOA, DOE, hospital number, room number, lab number, physician, and physician’s pharmacy code number
Use one Test Requisition form only
Label each specimen with the patient’s name, and time of specimen collection
Write the Total number of specimens submitted on the Test Requisition form Specimens should be sent in individual plastic bags/ set upright in a holder or rack, separated from the request form to prevent contamination in event of leaking
Without separating the needle from the syringe place both together with the swab and any dressings in a puncture-resistant container