Why Is Cbc Blood Test Ordered
CBC blood test is a common blood test that is ordered to check the overall health status of a patient. It is even ordered in case of inflammation, infection, unexplained bruising, bleeding, etc. Patients, who complain of weakness or fainting spells are also ordered the same. In some cases, it is ordered to check a medical condition or monitoring a medical treatment given to a patient.
Sexually Transmitted Disease Tests
Many sexually transmitted diseases can be diagnosed using a blood sample. These tests are often combined with urine samples or swabs of infected tissue for more accurate diagnoses.
The following STDs can be diagnosed with blood tests:
Blood tests arent always accurate right after contracting an infection. For an HIV infection, for example, you may need to wait at least a month before a blood test can detect the virus.
Most Frequent Fasting Blood Test Lists:
If your doctor asks for a blood test out of this list, please take the lab advice and your doctor recommendations about medications.
- Fasting blood glucose test requires 8 to 10 hours fasting period before taking the blood sample, only water is allowed, no eating, snacks, caffeine, fruits, or juices.Glucose tolerance test test requires 6 hours fasting from foods and drinks before the first sample.Glycated hemoglobin test does not need fasting because A1C levels independent on glucose levels which affected by meals or antisugar pills.Why fasting before a sugar test? Because blood glucose level is rapidly increase 30 minutes after meals and rapidly reduced after taking glucose-reducing medications.
- The Comprehensive Metabolic Panel tests require 10 to 12 hours fasting from foods, drinking, alcohols, smoking, snacks, except drinking water which is not affecting CMP results, CMP blood tests include the following tests:
However, some tests from CMP doesnt require fasting if its requested alone, see non-fasting blood tests list below.
Do You know: what does high cholesterol level mean?
Why fasting from alcohols is must for GGT test?As alcohols and smoking cause damage to your liver integrity and release GGT enzyme from liver cells into the blood stream, Alcohols are the primarily responsible for the high level of the GGT enzyme in the blood, GGT is an alcohol fasting blood test.
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/6why Fasting Is Important
Fasting means to avoid eating and drinking anything before the test is conducted. It is required before some tests for accurate results. Food and fluid are broken down into smaller molecules in our stomach which are later absorbed by the blood. This can alter the level of a certain substance in the blood like sugar, iron, cholesterol.
What To Expect During Tests
While fasting for blood tests is important, there are other things to know as well. Here is exactly what happens during different tests. Take cholesterol test for example:
A blood test ordered to check your cholesterol levels is usually done in the morning to get accurate results. A lab assistant will clean the puncture site, insert a needle, and draw some blood from a vein. They will also wrap an elastic band around your upper arm before inserting the needle this helps your veins to pop out a bit. After they collect the sample, they will cover the puncture site with a bandage. It usually takes a couple of minutes for the whole procedure to complete.
You do not need to take special care after your test. You can even drive and resume your normal activities immediately after the test. If you have been fasting for the last 12 hours, bring a snack with you to eat after the test. Your doctor will share the test results with you and explain what different values mean. If they find anything abnormal, they may ask you to have another test in a few weeks or months time.
Do I Need To Fast For My Thyroid Test
Usually,no special precautions including fasting need to be followed before taking a thyroid test. However, your pathologist can guide you better. For example, if you have to undergo some other health tests along with thyroid hormone levels, you may be asked to fast for 8-10 hours. Drinking water doesnt come under violation of fasting.
Is It Better If A Patient Fasts More Than 12 Hours
Patients should not fast for longer than 12 hours. While fasting is critical to these blood tests reliability and validity, over fasting can result in dehydration or other side effects. When fasting, remind patients that sleep also counts as fasting. For instance, if they have an 8 AM appointment, sleeping from 9 PM to 7 AM counts as 10 hours of fasting, as long as they do not eat in the morning before the appointment.
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Ask The Doctor: What Blood Tests Require Fasting
Q.Sometimes my doctor tells me it’s okay to eat before a blood test, and sometimes it isn’t. Why is that?
A. Actually, fasting affects the results of very few blood tests. For example, measurements of kidney, liver, and thyroid function, as well as blood counts, are not influenced by fasting. However, fasting is required before commonly ordered tests for glucose and triglycerides for accurate results.
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/6tests That Require Fasting
You do not have to fast for all kind of blood tests. Some can be performed at any time of the day. Here are some tests in which you are required to fast.
Fasting blood glucose test
This test is mostly for diabetic patients to diagnose the amount of sugar in the blood. A fasting blood glucose test is required to know if the glucose level in the body is balanced or not. For this test, one has to fast for 8 to 10 hours.
This test helps to determine the amount of good and bad cholesterol level in the body. High cholesterol level is linked with a different disease like the cardiac issue. One has to avoid foods and liquids other than water for 9 to 12 hours before the test. In some cases fasting is not important, so follow your doctor’s instructions
Iron blood test
This test is to determine the amount of iron in the blood, which can cause iron-deficient anaemia. You will be asked to fast from the morning and avoid taking any kind of supplement for 24 hours before the test.
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Oral Glucose Tolerance Test:
Glucose is the main source of energy for our body. Insulin produced by pancreas is responsible for absorbing glucose to drive out energy.
Oral Glucose Tolerance Test is a blood test done to determine how well our body is making use of the glucose intake. Or in other words, how efficient is our pancreas in producing insulin for the purpose. The bodys inability to generate insulin sufficient to absorb and use the glucose in blood, results to high blood glucose levels.
Doctors may order the test when following symptoms are experienced:
- Uncontrolled hunger and thirst
- OGTT is also performed as a mandatory test during pregnancy
Thyroid Hormone Test Results
Other medications can interfere with thyroid laboratory measurements, but not with the actual functioning of the thyroid.
A few examples of these medications include:
- Certain nonsteroidal anti-inflammatories
Lastly, research has found that the supplement biotin can interfere with the measurement of thyroid blood tests. Therefore, it’s recommended that people who take biotin stop doing so two days prior to having their thyroid blood tests.
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What Should I Take Care Of After Getting Tested For Thyroid Hormones
Once the blood sample for thyroid test is drawn, you can return to normal activities, including driving. A simple thing that you can follow is to avoid strenuous activity with the arm from where the sample was taken for a few hours after the test. If you experience any pain or bleeding, apply ice packs
Can I Request My Own Laboratory Tests
You can use QuestDirect to select and pay for lab tests. Licensed professionals from PWNHealth LLC and affiliated professional entities will provide clinical oversight of your lab testing, including ordering your selected tests, when appropriate. Then, have your specimen collected for the testing you purchased. Quest offers testing you can purchase for yourself, with physician oversight, as follows:
- Tests with an In-Person at Quest or In-Person at Drive-Thru option can be purchased in all states except Arizona, Alaska, and Hawaii, as well as Puerto Rico.
- Tests with an At-Home Kit option can be purchased in all states except Arizona, New York , Alaska, and Hawaii, as well as Puerto Rico.
Please note that New York residents may only purchase an at-home kit for a COVID-19 Active Infection Test. New York residents may not purchase any other at-home kits.
We strongly recommend that you share your test results with your doctor in order to make the best health decisions.
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Fasting Blood Glucose Test
A fasting blood glucose test can diagnose diabetes.
Diabetes is a condition that can lead to there being too much sugar in the blood. A fasting blood glucose test measures levels of sugar in the blood to see if they are healthy.
It is important that a person has not had anything to eat or drink other than water for 8 to 10 hours before a fasting blood glucose test. Fasting helps ensure that the blood test records an accurate measure of fasting blood sugar levels. The results help a doctor to diagnose or rule out diabetes.
Who Orders My Blood Tests
Your doctor typically orders blood tests for you during a physical, checkup, or an appointment intended for a specific condition.
Blood testing is usually partially or fully covered by insurance. Ordering tests through your medical provider ensures that youre not paying too much. Your doctor can also advise you on how to choose testing facilities that are reliable, well-managed, or convenient for you.
Its possible to order your own blood tests without a doctor or even health insurance, but its not recommended. You may end up paying the full cost by not going through an insurance plan, which can be expensive.
And some blood testing facilities may not give you accurate results. One infamous case of this is Theranos, a Palo Alto, California, biotechnology firm shut down in 2018 when an investigation uncovered lies and fraud around the accuracy of its private blood testing technology.
Normal levels can also vary by age.
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Non Fasting Blood Test Lists:
Non-fasting blood tests are those tests which their readings dont obviously affected by foods or drinks, it means theyre tested randomly at any time during the whole day.
- A1C test is not requiring a fasting period prior to sampling because it depends on glucose particles attached to RBCs surface and not depends on the circulating glucose.
- CBC blood test is not requiring a fasting period prior testing because it is only counts the blood cells, blood cells count not affected by food type in general.
- Thyroid function tests does not need fasting period, because thyroid hormone is responsible for metabolism processes, hence T4 and T3 is not a fasting blood test.
- TSH blood test isnt a fasting blood test.
- PSA blood test fasting is not needed, you dont have to fast from foods and drinking before taking prostate specific antigen test, as no study yet to told us about influence of PSA levels by some foods, however high PSA medications are responsible for lowering PSA levels, so that consult your urologist when testing PSA with taking its medications.
- Blood group type and RH tests does not require fasting before identify the ones blood type.
- Cancer antigens blood tests are not fasting tests in general, when testing for Cancer antigen CA.19.9, it is preferred to fast
Why Do I Need To Fast Before My Blood Test
If your health care provider has told you to fast before a blood test, it means you should not eat or drink anything, except water, for several hours before your test. When you eat and drink normally, those foods and beverages are absorbed into your bloodstream. That could affect the results of certain types of blood tests.
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What If I Accidentally Eat Or Drink Before My Blood Test
If you have been instructed to fast before your blood test and you accidentally eat or drink something during the fasting window, it is important to notify your healthcare provider or the person drawing your blood. If you dont, your results could be incorrectly interpreted.
It may be possible for your healthcare provider to interpret the non-fasted test results. Most likely, they will instruct you to reschedule the blood test at a time when you will be able to successfully complete the fast before the test.
Your physician will let you know the steps you need to take before your blood test, including whether or not fasting is required and for how long. By following all testing instructions and best practices , you can ensure a smooth testing process and the most accurate results.
How It Is Done
The health professional taking a sample of your blood will:
- Wrap an elastic band around your upper arm to stop the flow of blood. This makes the veins below the band larger so it is easier to put a needle into the vein.
- Clean the needle site with alcohol.
- Put the needle into the vein. More than one needle stick may be needed.
- Attach a tube to the needle to fill it with blood.
- Remove the band from your arm when enough blood is collected.
- Apply a gauze pad or cotton ball over the needle site as the needle is removed.
- Apply pressure to the site and then a bandage.
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Real Email Address Is Required To Social Networks
Health check-ups can be a nerve wreaking experience and full of anxiety at times. Procedures need to be explained and understand clearly so that prior misconceptions can be avoided. Some patients may wonder why fasting is necessary prior to the blood test. Questions that normally comes to mind are: Can the blood sample be taken immediately upon arrival at the hospital or are there any other options available?
Blood Sugar test
Health check-up may require 3 visits to the hospital:
During the first visit, you need to consult a doctor and have an appointment for blood test.
On the second visit which is the test date, you have to fast for 8-14 hours prior to the test, approximately from 8.00 p.m. the night before, until the blood sample is drawn.
There are 2 reasons for 12-hour fasting prior to the blood test
Firstly, fasting blood sugar level is required for diabetes risk analysis . If the result is categorized as pre-diabetes , in accordance to the Clinical Practice Guidelines of the Diabetes Association of Thailand, the oral glucose tolerance test would then be recommended. Those undergoing the test would have to do the following:
need to fast on the test date
drink syrupy glucose solution
have blood sugar test every 30-60 minutes for 2-3 hours
Secondly, fasting is necessary for the following tests:
Blood Lipid test
Get The Home Care You Need With Kinkaid:
If you or your loved one is in need of an at-home blood draw, please reach out to us to see how we can help. Kinkaid Private Nursing Care offers premium in-home services to patients looking for the best and most intensive care on the market. We only take on a few clients at a time, so we always provide specialized care to meet the needs of each client.
For more information, please visit our homepage and learn about the array of services we provide. These services include at-home blood draws, in-home nursing care, and the coordination of a variety of at-home medical services in the Los Angeles area, as well as home detox services all over the state of California. We also offer at-home Covid-19 testing.
Jennifer is a healthcare executive, and the founder of Kinkaid Private Care, a private health management company specializing in assisting patients in their homes with complex medical diagnoses. Jennifer is a registered nurse with more than 20 years of experience working in some of the most highly regarded hospitals in Los Angeles and Orange County. Over the years she has developed an extraordinary network of highly qualified nurses with various specialties. This network allows her to provide the best medical experience and match specialized nursing care to the specific needs of her clients.
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Preparing For Your Test
12 hours is the optimal fasting period. Fasting longer than the recommended time could compromise your results. You may be advised to defer the test to another day.
General Fasting information
To ensure your test is accurate it is important to adhere to the following:
- Have nothing to eat or drink for at least 10 to 12 hours – preferably an overnight fast
- If you are thirsty, sips of plain water only are permitted. .
- You are advised to avoid smoking
- You are advised not to chew gum
- If you take medication, please continue to take your medication as prescribed
- If you are diabetic please consult your doctor prior to fasting
12 hours is the optimal fasting period, but 10-14 hours is acceptable. Fasting beyond 14 hours affects the quality of the result.
Tips for nervous patients
If blood tests make you nervous, we have special options that will put you at ease.The first step it to let us know how youre feeling. If you have a tendency to become lightheaded when your blood is taken, our staff can have you lie down. This will help you to relax. If you start to feel faint, you can just close your eyes and breathe deeply. Our staff encounter nervous patients all the time are ready to help in any way they can.Practising self-care can also help to ease anxiety.
- Focus on your breathing
- Talk about your family, pets, or things you enjoy
- Try not to hold your breath, tense up or look at the needle.
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