Description of Complete Blood Count (CBC)
Table of Contents
The Complete Blood Count (CBC) is a fundamental blood test that provides valuable information about the overall health and well-being of an individual. By analyzing various components of the blood, this test helps medical professionals in diagnosing and monitoring a wide range of conditions. In this blog post, we will explore the definition, indications, sample type and collection, sample analysis, interpretation, and the utility of the CBC test. Its also reffered to as Full Hemogram (FHG), or Full Blood Count(FBC).
It utilizes automated blood cell counting to determine various blood parameters. These include red and white cells, platelet and hemoglobin parameters.
Indications: When is CBC ordered?
The CBC test is commonly ordered by healthcare professionals for various reasons, including routine check-ups, pre-surgical evaluations, and monitoring the progress of certain medical conditions. Some of the commonly used situations include:-
- Infectious diseases eg pneumonia, meningitis,
- Hematologic conditions eg Anemia, Sickle cell disease, coagulation disorders
- Inflammatory conditions e.g rheumatoid athritis,
- Cancers e.g leukemia,
- Hypersensitivity conditions eg Asthma
- Baseline workup for patients undergoing surgery, chemotherapy
- Disease and therpay monitoring
Test Type
CBC is a laboratory-based test. Newer analysers can be used in doctor’s office or point of care settings.
Procedure and Equipment for complete blood count
Hematology Analyser is the equipment used to perform complete blood count. They vary in complexity from 3, 5 and 7 parameter
Hematology analyzers come in different sizes and capabilities. Most typical in the average laboratory is a single test machine. In busy facilities, bigger analyzers with batch processing capabilities are used.
In terms of capabilities, they are categorized as follows:
- 3- parameter
- 5- parameter
- 9-parameter
Sample for complete blood count
CBC test is run on anti-coagulated, whole blood. Venous blood is used and collected in lavender/purple top (EDTA) vacutainer.
Sample Collection Procedure:
Blood for complete blood count is routinely collected from a peripheral vein in the forearm or antecubital fossae. Other sites are acceptable based on the clinical situation. We use EDTA (purple-top) tube for collection about 3-5ml of blood.
Sample Analysis
- Sample identified and checked if acceptable for analysis
- Depending on the machine, samples are labelled and put on the machine rack
- The analyser aspirates the correct amount for sample and carries out the analysis.
- Results are displayed on the screen. If satisfactory, they are printed and signed out.
Interpretation of CBC
Interpretation of CBC is vary with specific clinical situation . While there are reference ranges for each parameter, interpretation will take into account the entire clinical picture.
Please refer to our reference range page here