Collecting blood from an animal requires forethought and planning if the end result is to offer an accurate diagnosis. Before the blood collection begins, thought needs to be given to the patient’s comfort and safety, the tests requested, and the equipment required.

Planning for Blood Collection

A frightened patient can hinder the chances for successful blood collection. Carefully choosing a location that removes some of the strange sights, sounds, and smells can limit the patient’s unease. Making sure that all necessary equipment is within fingertip reach before beginning the blood draw will not only reduce the chance for erroneous results, but will also speed up the collection process and decrease the opportunity for the animal to react because of fear.
Steps to follow include:

• Choose a location for the blood draw that is clean, quiet, and in a low-traffic area
• Ensure that all necessary supplies are within grasp before bringing patient into the room, which may include such items as:
• Shaving kit
• Blood collecting kit:
• Syringes
• Needles
• Catheters
• Wipes
• Alcohol or disinfectant
• Muzzle
• Paper towels
• Have a helper ready to aid with:
• Shaving the site, if necessary
• Cleaning and disinfecting the site
• Patient restraint
• Filling of tubes
• Before the blood draw:
• All involved should follow established protocol:
• Clean and disinfect hands
• Wear gloves
• Communicate with helper to establish the order for collecting the samples

Patient Considerations

The site to draw blood may be determined by the size and accessibility of the blood vessels, but it is also dependent upon the animal and its health. Planning steps should take the animal’s condition and physical factors into consideration, for example:

• Stress level
• Injuries, trauma
• Wounds or skin infections
• Respiratory compromise
• Pain
• Temperament
• Breed characteristics, for example:
• Thick folds of skin
• Excessive coats

Equipment

When blood tests differ on their requirements for the draw site and the amount of blood collected, decisions need to be made in order to choose the proper equipment, for example:

• Syringe:
• Size may be dictated by:
• Sampling volume required
• Health of blood vessels
• Needle:
• Choice of gauge:
• Smaller gauge for little, fragile veins
• Larger gauge for high-volume sampling
• Catheter:
• Use is dependent on the need to exchange syringe

Once drawn, the blood needs to be placed into a collection tube. These tubes are vacuum-sealed, and each is created for a specific purpose and identified by the color of the tube stopper.
The following list identifies the tubes and their use:

• Red-topped tube
• Used for tests that require whole blood clotting
• No chemicals included in tube
• Orange-topped tube
• Serum separator tube (SST)
• Allows for the separation of blood cells from serum
• Clots in a way that cells can’t change the serum chemicals which would give false test results
• Serum is often used to test for glucose, calcium, liver enzymes, kidney toxins
• Lavender-topped tube
• Preserves blood cells, cells float free with no clotting
• Tube contains potassium EDTA which prevents clogging
• Used to count cells to screen for infections, identifies anemia
• Gray-topped tube
• Provides a more stable glucose level
• Tube contains sodium fluoride
• Used to determine blood sugar levels, monitor diabetic insulin treatment
• Light blue-topped tube
• Contains citrate
• Used for coagulation tests
• Dark blue-topped tube
• Contains sodium EDTA
• Used to detect trace minerals

The only way to get the accurate results for a specific blood test is to place the blood within the correct tube. When a blood draw requires various tubes for testing, prepare for collection by placing tubes in an order that prevents tube contamination. When collecting blood samples, it is always wise to begin by establishing a plan!

Want to learn more about ways to ease the comfort of your animal patients? Give your Covetrus representative a call today at 855.724.3461.