CBC Blood Test

What is a Complete Blood Count (CBC) Blood Test?

A Complete Blood Count (CBC) Test, also known as a CBC Blood Test, is a standard common blood test that counts blood cells, specifically the number of red blood cells, white blood cells, and platelets. It’s one of the safest blood tests and poses no risk to any patient. The test analyzes these cells to evaluate a person’s overall health status and check for signs of certain conditions related to blood and bone marrow.

Through this test, healthcare professionals can also identify abnormalities in a person’s bloodstream, heart, or lung disease and use the findings to determine the next set of tests to conduct to narrow down the possible conditions a patient may have and rule out others. Furthermore, this blood test is essential for cancer treatment because it can help detect all these and more by just taking a small amount of blood from a patient.

How to conduct a Complete Blood Count (CBC) Blood Test?

CBC Blood Tests are one of the most straightforward tests to conduct.

Step 1: Give reminders

Before the blood draw, healthcare providers must ask their patients about any medication they're taking that may affect the results and inform them that they are free to eat and drink as usual since the CBC test doesn't require fasting.

Step 2: Conduct the test

Here is a quick step-by-step on how to conduct the CBC test:

• First, they will have the patient sit down.
• Then, they will wipe the blood drawing site with antiseptic
• After cleaning the site, they will tie a band near the blood drawing site to help make the veins more visible
• They will use a needle to draw blood from a vein
• After drawing enough blood, they will remove the needle and cover the punctured site with a gauze pad or sterile bandage.
• They will send the blood sample to a laboratory for analysis.

Step 3: Analyze and interpret

The results should be ready within a day or two. Once they are, discuss your findings with the patient.  

From gathering patient history and information to analyzing and interpreting the results, feel free to use our free CBC blood test template to record the results, diagnosis, and next steps.

How are CBC Blood Test results interpreted?

Complete Blood Count measures different components that make up the blood. And though the average values for each component may vary from lab to lab, here's an overview of the possible problems the results can point to:

• Red blood cell count (erythrocytes): Anemia, kidney problems like chronic kidney disease, bleeding, malnutrition, heart problems, lung problems, polycythemia, dehydration
• Hemoglobin (protein in red blood cells that carries oxygen to tissues): Anemia, cirrhosis, cancer, malnutrition, bleeding, dehydration, polycythemia
• Hematocrit (the volume of red blood cells): Anemia, cirrhosis, cancer, malnutrition, bleeding, dehydration, polycythemia, hemochromatosis
• Blood sedimentation rate (how fast red blood cells sink to the bottom of the tube): Inflammations
• Red cell distribution width (RCDW or differences in red blood cell volume and size): Vascular diseases
• White blood cell count (leukocytes or a key part of the body's immune system, and provides insight into immune function) including subtypes like the monocyte, lymphocyte, neutrophil, basophil, and eosinophil: Infections, leukemia, and other immune system-related issues
• Platelet count (thrombocytes): Bleeding/clotting problems
• Mean corpuscular volume (MCV or average size/volume of red blood cells): Anemia, malnutrition, thalassemia
• Mean corpuscular hemoglobin (MCH or average amount of hemoglobin in red blood cells): Anemia, malnutrition, thalassemia
• Mean corpuscular hemoglobin concentration (MCHC or average amount of hemoglobin concentration in red blood cells): Anemia, malnutrition, thalassemia

When is it best to conduct a CBC Blood Test?

Here's a list of the best times to conduct CBC Blood Tests:

Patients present with particular symptoms

• If they have bruises or bleeding, especially for reasons unknown to them,

• if they feel weak and weary, especially if they get quickly tired despite not doing anything strenuous,
• if they have a fever,
• if they have headaches and feel dizzy,
• if they feel nauseated and have vomited because of nausea,
• if their joints hurt,
• if they have inflammations in their body,
• if their heart rate is abnormal,
• or if their blood pressure test is high or low.

Detecting blood diseases

If the patient has the following, they may have a blood disease, and a healthcare provider may conduct a CBC test to determine if the patient has said disease:

• If they have any deficiencies in vitamins and minerals
• If they have anemia (the state of not having enough red blood cells to scatter oxygen around the body)
• If the patient is dealing with any side effects of specific medication or chemotherapy
• If they have certain types of cancer
• If they have bacterial infections
• If they have a particular disease of blood or blood disorders
• If they have bone marrow disorders like bone marrow failure

Routine check-ups

Some people often schedule themselves for routine check-ups so they are always aware of the current state of their overall health. Suppose a CBC Blood Test picks up on abnormalities not present in previous results. In that case, the healthcare provider can work to detect underlying conditions early and provide treatment before they get any worse.

Patient monitoring

CBC Blood Tests are conducted to monitor the health status of patients diagnosed with a particular condition related to abnormal CBC Blood Test results. New results will help healthcare providers determine whether the patient's lung disease is getting better or worse, whether their treatment has any side effects, and whether the treatment plan is effective and working.