A sample of blood is drawn and examined under a microscope in a laboratory.
You do not need to fast ahead of time.
The results of a blood smear can help diagnose a variety of issues, from anemia to cancer.
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A blood smear test involves looking at a sample of blood under a microscope.
No other preparation is needed.
A phlebotomista healthcare professional who specializes in collecting and preparing blood for testingwill draw the sample.
Bloodwork
They will examine your arms inside the elbows to find a good vein.
They will then clean the area with an antiseptic and insert a needle.
You may feel a sting and some pressure.
Tape or bandage will then be applied.
Side effects may include bruising at the site of the blood draw or continued bleeding.
To minimize bruising, avoid lifting or carrying anything with that arm for a few hours after the test.
First, special stains are applied to the sample.
Possible Testing Errors
Certain errors can affect how accurate the blood smear results are.
These errors include:
Blood smears are often reviewed by a person, not a machine.
The experience of the person analyzing the smear (called ahematopathologist) can affect how it is interpreted.
What Can a Blood Smear Show?
A blood smear is used to take a more detailed look at your blood cells.
It can reveal important information about many blood-related conditions.
The results commonly include:
Sometimes a diagnosis can be made based on the blood smear alone.
For example:
Other times, the results of a blood smear indicate further testing is warranted.
It can also indicate leukemia.
Bands of young white blood cells often increase with serious infections.
The blood smear test can also show how many granules are in the platelets.
Granules are important in wound healing and inflammation.
Up close, the smear shows how many of each punch in of blood cell are present.
The process is simple: A technician draws a small sample of your blood using a needle.
The sample is spread onto a slide and then analyzed.
A blood smear helps healthcare providers identify illnesses and find out how well the body is functioning.
The results are even more useful when compared to the results of other tests, such as CBCs.
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