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This is sometimes referred to as “checking labs,” “doing bloodwork,” or even “checking blood.” Most older adults have been through this. For instance, it’s pretty much impossible to be hospitalized without having bloodwork done, and it’s part of most emergency room care. Such testing is also often done as part of an annual exam, or “complete physical.” Last but not least, blood testing is usually — although not always — very helpful when it comes to evaluating many common complaints that affect aging adults. Fatigued and experiencing low energy? We should perhaps check for anemia and thyroid problems, among other things. Confused and delirious? Bloodwork can help us check on an older person’s electrolytes (they can be thrown off by a medication side-effect, as well as by other causes). Blood tests can also provide us with information related to infection, kidney function, and much more. Like much of medical care, blood testing is probably overused. But often, it’s an appropriate and an important part of evaluating an older person’s health care concerns. So as a geriatrician, I routinely order or recommend blood tests for older adults. Historically, laboratory results were reviewed by the doctors and were only minimally discussed with patients and families. But today, it’s becoming more common for patients to ask questions about their results, and otherwise become more knowledgeable about this aspect of their health. In fact, one of my top recommendations to older adults and family caregivers is to always request a copy of your laboratory results. (And then, keep it in your personal health record!) This way, if you ever have questions about your health, or need to see a different doctor, you’ll be able to quickly access this useful information about yourself. In this article, I’m going to list and briefly explain the blood tests that are most commonly used, for the primary medical care of older adults. Specifically, I’ll cover four “panels” which are commonly ordered, and then I’ll list six more blood tests that I find especially useful. In other words, we’re going to cover my top ten blood tests for the healthcare of aging adults. I’ll finish with some practical tips for you to keep in mind, when it comes to blood tests. 4 common “panels” in laboratory blood testing1. Complete Blood Count (CBC) What it measures: A CBC is a collection of tests related to the cells in your blood. It usually includes the following results:
The CBC can also be ordered “with differential.” This means that the white blood cells are classified into their subtypes. For more information on the CBC test, see Medline: CBC blood test. For details on the white blood cell count differential, and what the results might signify, see Medline: Blood differential test. What the CBC is often used for:
2. Basic metabolic panel (basic electrolyte panel) What it measures: Although it’s possible to request a measurement of a single electrolyte, it’s far more common for electrolytes to be ordered as part of a panel of seven or eight measurements. This is often referred to as a “chem-7,” and usually includes:
What the basic metabolic panel is often used for:
For more details on these tests, see Medline: Basic Metabolic Panel. From this page, you can find links to additional pages which explain each of the above electrolytes and metabolic components in detail, including common causes of the result being abnormally high or low. 3. Comprehensive metabolic panel What it measures: This panel includes the items above in the basic metabolic panel, and then usually includes an additional seven items. For this reason, it’s sometimes referred to as a “chem-14” panel. Beyond the seven tests included the basic panel (see above), the comprehensive panel also adds:
What the comprehensive metabolic panel is often used for:
For more details on these tests, and the possible causes of abnormal results, see Medline: Comprehensive Metabolic Panel. 4. Lipid (cholesterol) panel What it measures: These tests measure the different types of cholesterol and related fats in the bloodstream. The panel usually includes:
People are often asked to fast before having their cholesterol checked. This is because triglycerides can increase after eating, and this can cause a falsely low LDL to be calculated. However, research suggests that in most cases, it’s not necessary for people to fast; it’s inconvenient and only makes a small difference in test results. What the lipid panel is often used for:
6 more blood tests that I order oftenHere are six other types of tests that I often order on my older patients: 1. Tests related to thyroid function What these measure: These tests can be used to screen for thyroid disorders, or to help calibrate the dosage of thyroid replacement medications. The most commonly used tests are:
In more complicated situations, other tests related to thyroid function may also be ordered. What these tests are often used for:
For more information about thyroid problems in older adults, see HealthinAging.org: Thyroid Problems. You can also read a more in-depth scholarly article here: Approach to and Treatment of Thyroid Disorders in the Elderly. 2. Tests related to vitamin B12 levels What these measure: These measure the serum levels of vitamin B12 and provide information as to whether the level is adequate for the body’s needs. The two tests involved are:
Depending on the situation, if an older adult is found to have low vitamin B12 levels, additional testing may be pursued, to determine the underlying cause of this vitamin deficiency. What these tests are often used for:
3. Glycated hemoglobin (Hemoglobin A1C) What it measures: Glycated hemoglobin is formed in the body when blood glucose (blood sugar) attaches to the hemoglobin in red blood cells. It is normal for glucose to do this, but if you have more glucose in the blood than normal, your percentage of glycated hemoglobin will be higher than normal. The higher one’s average blood sugar level, the greater percentage of glycated hemoglobin one will have. A result of 6.5% or above is suggestive of diabetes. For more information:
What this test is usually used for:
4. Prothrombin time (PT) and International Normalized Ratio (INR) What it measures: These two tests are used as a measure of how quickly a person’s blood clots. People taking the blood-thinner warfarin (brand name Coumadin) must have this regularly monitored. For more information:
What this test is usually used for:
5. Brain natriuretic peptide (BNP) test What it measures: Despite the name, BNP levels are mainly checked because they relate to heart function (not brain function!). BNP levels go up when a person’s heart cannot pump blood as effectively as it should, a problem known as “heart failure.” For more information on this test:
A related, but less commonly used, test is the “N-terminal pro-B-type natriuretic peptide” (NT-proBNP) test. What this test is used for:
6. Ferritin What it measures: The body’s serum ferritin level is related to iron stores in the body. For more about this test:
Depending on the situation, if an older person’s iron levels need further evaluation, additional tests can be ordered. What this test is used for:
Obviously, there are many more tests that can be ordered as part of the medical care of older adults. But the tests I cover above are, by far, the ones I order the most often. Tips to help you benefit from your blood tests and resultsHere are my top tips: 1. Be sure you understand why a given test is being ordered. Is it meant to help evaluate a symptom? Monitor a chronic condition? Assess whether a treatment is working? You will understand your own health issues better, if you ask questions about the purpose of the blood tests your doctors are proposing. In general, blood tests should only be ordered for a reason, such as to evaluate a concerning symptom, to monitor a chronic disease, or to check for certain types of medication side-effect. Keep in mind that it’s only occasionally appropriate to order blood tests for “screening.” A screening test means a person doesn’t have any symptoms. Such screening blood tests are only recommended for a handful of conditions. For more on preventive health care and screening tests that may be appropriate for older adults, see 26 Recommended Preventive Health Services for Older Adults. 2. Ask your doctor to review the results and explain what they mean for your health. Try to look at the report with your doctor. It’s especially important to ask about any result that is flagged as abnormal by the laboratory system. For instance, I have found that many older adults are unaware of the fact that they have mild or moderate kidney dysfunction, even though this has been evident in prior laboratory tests. This happens when people do not review reports and ask enough questions. Wondering why the doctor wouldn’t tell an older person that the kidney function is abnormal? Well, if it’s been going on for a while, the doctor might think the older person already knows about this issue. Or perhaps the doctor mentioned it before, but the older person didn’t quite hear it. It’s also not uncommon for doctors to just not get around to mentioning a mild abnormality that is pretty common in older people, such as mild anemia or mild kidney dysfunction. 3. Ask your doctor to explain how your results compare with your prior results. Laboratory reports will always provide a “normal” reference range. But what’s usually more useful is to see how a given result compares to your previous results. For instance, if an older person’s complete blood count (CBC) shows signs of anemia, it’s very important to look at prior CBC results. This helps us determine what the “trajectory” of the blood count is. A blood count that is drifting down — or worse yet, dropping fairly suddenly — is much more concerning than one that has been lower-than-normal, but stable for the past year. Ditto test results suggesting diminished kidney function, and for many other abnormal blood test results. Of course, you’ll want to understand what might be the cause of an abnormal result regardless of the trajectory. But a worsening blood test result usually means the issue is more urgent to sort out. 4. Request copies of your results, and keep them in your own record system. Past laboratory results provide incredibly useful information to health providers, and can be very useful to you as well. If you keep your own copies of results, you’ll be better able to:
For instance, one of my family members recently had a “routine” cholesterol panel done. He takes no medications, is quite fit, and is in good health, so he was surprised when some of his results came back higher than normal. We promptly reviewed his previous results, from three years ago, and found that those results were within normal range. So this family member is now in the process of reconsidering his diet. If he hadn’t had copies of his previous labs, he could have asked his doctor. But it’s much faster and more convenient to be able to look in your own records! And don’t just rely on looking up past results through a patient portal. Clinics will often remove your access, if you are deemed to have left the practice. So it is very important to keep your own copies of results. For more on the benefits of maintaining your own personal health record — or a health record for an older parent — see How to Use a Personal Health Record to Improve an Older Person’s Healthcare. This article was first written in 2017. It was reviewed and minor updates were made in January, 2022. Which laboratory results would the nurse expect to find when assessing a patient with MDS?For other people, MDS might be suspected based on the results of blood tests that are done for another reason. In either case, if MDS is suspected, you will likely need tests to look at your blood and bone marrow cells to see if you have MDS or some other health condition.
What blood cells would the nurse expect to find elevated as the result of infection?See Figure 9.22 for an illustration of a complete blood count with differential. When there is an infection or an inflammatory process somewhere in the body, the bone marrow produces more WBCs (also called leukocytes), releasing them into the blood where they move to the site of infection or inflammation.
Which condition is the most common cause for Hematemesis quizlet?Conditions that most commonly cause hematemesis include: Bleeding ulcers. A peptic ulcer is an open sore in your stomach or duodenum. It's often caused by a bacterial infection, or by the regular use of NSAIDs or aspirin.
Which symptom would the nurse expect to find in a patient with vitamin B12 deficiency?Key points about vitamin B12 deficiency anemia
Without enough oxygen, your body can't work as well. Symptoms include weak muscles, numbness, trouble walking, nausea, weight loss, irritability, fatigue, and increased heart rate. Treatment may include vitamin B12 supplements.
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