Blood Tests: What You Need to Know

Spoiler alert: An abnormal result isn’t cause for panic.
Black female medical professional draws blood on male patient

Let’s face it: Nobody looks forward to blood tests, but they’re quick, relatively easy and can tell you and your provider a lot about your health.

Some blood tests are screening labs, like those ordered as part of a wellness exam, while others are used to monitor a condition or answer a specific question about your health. They can also help diagnose a specific health issue or condition like diabetes, high cholesterol or even cancer. Your provider can discuss with you when it may be worth considering a blood test to help you both make appropriate decisions about your health care.

What Are the Different Types of Blood Tests?

When a blood test is ordered by your provider, that single blood draw may be used for one specific test or a variety of tests. Below are some blood tests your doctor may order to help better understand your health or help inform the care you receive:

  • CBC (Complete Blood Count): This is the go-to test for red blood cells, white blood cells and platelets. It may help identify infection, autoimmune disorders, anemia, leukemia and other cancers.
  • BMP (Basic Metabolic Panel): The BMP measures your electrolytes, kidney functions and blood sugar levels.
  • CMP (Comprehensive Metabolic Panel): This test includes the BMP with additional tests related to liver function.
  • Hemoglobin A1C (HbA1C): The A1C measures the average amount of glucose, or sugar, in your blood over the past three months. It helps screen for or diagnose prediabetes and diabetes. If you have diabetes, it is used to help you and your provider monitor and manage your treatment plan.
  • Cholesterol or Lipid Panel: These tests help assess your “good” (HDL) and “bad” (LDL) cholesterol levels and your triglycerides, or the fat in the blood. Your provider reviews the results along with your overall health and risk factors. They will also use them to estimate your risk for heart attack and stroke. Knowing your risks allows you and provider to have a conversation on what lifestyle changes or medications might benefit your health.
  • Hepatitis C Virus (Hep C): This antibody test determines whether you’ve ever been exposed to the hepatitis C, a viral infection of the liver that can lead to serious health complications.
  • Human Immunodeficiency Virus (HIV): This screening test checks your blood for the presence of HIV, a virus that causes HIV infection and attacks certain infection-fighting cells in your immune system.
  • Sexually Transmitted Disease (STD) or Infections (STI): Blood tests for STDs or STIs may include a number of screenings, like hepatitis C, human immundodeficiency virus (HIV) and syphilis, a bacterial infection that, left untreated, can permanently damage your heart, brain and other organs. Diagnosis can help protect your health and the health of your partner(s).

How Often Do I Need a Blood Test?

The frequency of blood tests depends on your health conditions, symptoms, and the information your doctor needs. For instance, you might need an annual lipid panel screening if you have high cholesterol. If you have diabetes, you need to get your blood tested every three to six months to measure blood sugar levels. During radiation or chemotherapy, regular blood tests help your care team monitor your body’s response to treatment.

Your doctor might also suggest a blood test to diagnose or rule out a condition. “Sometimes a patient has a new complaint, such as ‘I’m fatigued,’ ‘I'm cold,’ or ‘I'm gaining weight,’” says David Ziegelman, MD, an internal medicine physician from University of Vermont Medical Center. “A lot of times, people's conditions are temporary. But let's say they're still tired after months – then we need to dig deeper.”

What Does an Abnormal Blood Test Result Mean?

Blood test results are often available within 24 hours and can be accessed in MyChart, the UVM Health Network’s electronic patient portal. You may see your results before your provider sees them. So what should you do if you see a number that’s “high” or “low” before your provider contacts you to discuss your results?

First, don’t worry. Several factors can cause abnormal levels. “When people fast for their blood test, they sometimes don’t drink enough water and get dehydrated. Or they don’t fast, and their blood sugar comes back high,” says Jeremiah Eckhaus, MD, a family medicine physician at University of Vermont Health Network - Central Vermont Medical Center. “Those things can cause the test result to come back abnormal. But when the physician looks at the test results, they know that the abnormal reading isn’t anything concerning.”

Rest assured – your provider will review your test results. If there’s a concern or problem, your provider will let you know. They may then order a follow-up test or may recommend waiting a while before retesting.

“I try my best to give patients context before I order something. I’ll say, ‘Here’s what I'm thinking it could be, what I’m curious about, or what I’m worrying about,’” says Natasha Withers, DO, a family physician at University of Vermont Health Network - Porter Medical Center. “I try to prep them beforehand.”

What If I’m Afraid of Needles?

If you’re scared of needles, the thought of a blood draw can create anxiety and tempt you to avoid the test altogether. But skipping a blood test can leave questions about your health unanswered and potentially lead to unwanted consequences. Don’t skip the test! Instead, Dr. Ziegelman says, try these tips to calm your nerves:

  • Talk It Through: When you arrive for your blood test, tell the phlebotomist (the person drawing your blood) you are nervous. They can answer your questions, help you relax and distract you through conversation. You can also ask to lay down for the test, which can help you relax.
  • Turn Your Attention Elsewhere: Try not to focus on process. Look away or close your eyes. Think about something you enjoy, talk to the phlebotomist or listen to soothing music through headphones.
  • Breathe and Relax: Before the test begins, relax your shoulders and arms and take deep, slow breaths. Remember to focus on your breathing to calm your mind.

“Our phlebotomists are very used to someone coming in who does not like needles,” Dr. Ziegelman says. “We stay very calm and don’t make a big deal about it.” The team is there to help ease your nerves and complete the procedure as quickly and painlessly as possible.

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