Is it necessary to draw blood on an empty stomach?

Question 1: Do you need to draw blood on an empty stomach for routine blood tests? Hello. I work in a hospital laboratory. Generally speaking, blood routine does not need an empty stomach, but generally we should ask patients to take it on an empty stomach because.

First of all, the standard values of many blood tests are tested on an empty stomach and then formulated, that is, the standards are carried out on an empty stomach.

Second, if other items need to be tested at the same time as routine examination, if other items need to be tested on an empty stomach, there is no need to draw lots again the next day. Direct injection is enough, so we usually advise patients to take it on an empty stomach just in case.

Blood routine, hormones and immunity. Whether you are on an empty stomach has little effect on the result, so if you accidentally eat something, it's not a big problem. But there are strict requirements for blood sugar, blood lipid and liver function. Because eating will have a greater impact on your grades.

So I suggest you go on an empty stomach. As for whether to take medicine, you should ask the doctor. The doctor asks to stop taking the medicine and then take the test, or to take the test during taking the medicine, depending on the specific needs.

Question 2: Do you want to take blood on an empty stomach to measure liver function? Liver function test must be done on an empty stomach. The fasting time is generally 8~ 12 hours, especially for the first time to check the liver function. It is best to abstain from alcohol the day before the blood test. There is a certain relationship between the measured values of many contents of liver function test and diet. For example, drinking alcohol can easily increase some serum enzyme values, while eating greasy food will increase blood lipids.

Blood was drawn at 9: 00 a.m. when liver function was performed, and the result given by the hospital was 1 1. I wonder if this is the case in your place.

Doctors usually arrange fasting blood test in the morning, because the physiological condition of human body is the most stable in the morning. Check that the dinner time the day before is not too late, eat food and don't drink.

Question 3: Which tests need to draw blood on an empty stomach in the morning? Generally, the items that need fasting blood test in the morning are: 1, and various blood chemistry tests. Blood sugar, total blood lipid, cholesterol, triglyceride, β-lipoprotein, serum protein electrophoresis, carbon dioxide binding capacity, various serum enzymes, alpha-fetoprotein, serum immunoglobulin, mucin, etc. 2, blood liver function test. 3. Determination of blood and renal function. 4. Glucose tolerance test. 5. Serological and immunological examination. For example, total complement, C3, rose petal test, antinuclear antibody, hepatitis B surface antigen, widal reaction, determination of anti-streptolysin "O" and examination of rheumatoid factor. 6. Measurement of hemorheology. Such as whole blood viscosity, plasma viscosity, serum viscosity and platelet viscosity. Some blood tests can be checked at any time, such as red blood cells, white blood cells and platelets. Some blood tests need to be carried out on an empty stomach (without breakfast) in the morning, such as renal function, liver function, erythrocyte sedimentation rate and blood sugar. This is because: first, avoid the influence of diet and other factors on some components in the blood. Because food is absorbed by gastrointestinal tract into blood, and then transported to the whole body by blood, the concentration of some components in blood will increase, which will affect the accuracy of test results. Secondly, after eating, all kinds of digested food chyle particles are quickly absorbed into the blood, which makes the blood appear turbid, usually called "fatty blood", which makes it impossible for inspectors to observe clearly. Third, the mood is relatively stable in the morning, and the body is in a state of basal metabolism. The results can truly reflect the actual situation. Fasting means not eating after dinner and not eating breakfast the next morning. In this case, blood test is the best method.

Question 4: I want to ask the blood test doctor to say that I should eat on an empty stomach. Generally speaking, how long does it mean not to eat? First, the collection time of fasting blood. Fasting blood usually refers to blood that has not eaten in the morning, and is taken from 8 days12 hours after the last meal. After eating, many substances in the blood will change temporarily, which cannot reflect the real situation of the body. Fasting blood is usually collected in the morning and 6 hours after a light diet if necessary. 2 weeks before blood lipid test, you should keep your usual eating habits, and take blood after meals 12 hours.

Second, it is not advisable to exercise more before blood collection. A kind of sport is static, that is, it lasts for a short time, but its intensity is high, such as weightlifting and pitching. It uses the energy stored in muscles and has little effect on the laboratory. Another kind of sports is dynamic, that is, sports with long duration and low intensity, such as long-distance running, swimming and cycling. This requires a lot of heat to maintain and has a great influence on the test results, so it should be avoided as much as possible 2 days before the test.

Third, don't take a lot of vitamins before blood collection, otherwise some test results will be distorted. For example, taking large doses of vitamin C will affect the results of urine sugar.

Fourth, please stretch your ring finger when taking blood from your fingertips. Peripheral blood sampling is suitable for detecting items with blood volume less than 0.0 ml, such as peripheral blood sugar. Usually choose the side of the fingertip of the left ring finger. First of all, there are abundant blood vessels in this area. Second, it will not affect the fingers to continue to touch objects after rest.

Question 5: Why do physical examinations have to be performed on an empty stomach? When people need to test their liver function, blood sugar and blood lipids, doctors always ask them to take blood on an empty stomach the next morning. For this reason, some patients are afraid that eating will affect the test results, and even wait for the test without eating anything the night before blood drawing. Here, many people think that such fasting blood test results are accurate, but this is not the case.

The doctor told the patient to have a blood test on an empty stomach, not to let the patient go hungry, and not to let the patient check the results after being hungry for more than ten hours. Because if the body is hungry, the number of functional indicators in the body will change, which will lead to the collection of blood samples different from usual. Therefore, even if the results of such examinations are "normal", they cannot accurately reflect the real situation of patients.

Hunger has a particularly obvious impact on diabetics, because if you are hungry for a long time, you will have hypoglycemia shock, cold sweat and even faint. Finally, you have to inject or take oral glucose to save your life. Even if there is no shock, because the fasting time is too long and the blood sugar test result is very low, it is easy to be mistaken for good blood sugar control, which not only harms oneself but also misleads doctors. There are also some diabetics who are extremely sensitive to their own blood sugar regulation. When they are hungry for a long time, they will immediately mobilize glycogen in their bodies for urgent need. At this time, their blood sugar is much higher than usual, and this result is incorrect, which will mislead doctors and add trouble to treatment. Therefore, diabetic patients must eat dinner overnight before testing fasting blood glucose.

So, what is an empty stomach? The specific requirements are: the night before blood drawing, patients should maintain their usual living habits and eat normally; Food should be light, don't drink; Don't drink coffee or strong tea after meals; Have a good rest. After getting up the next morning, don't eat breakfast, drink less or no water, don't do morning exercises, and calmly wait for blood collection in the hospital. Such a blood sample is a good sample to reflect the real situation.

Some patients have so high triglycerides that serum, like milk, affects the accuracy of other blood ester test results. At this time, the doctor will ask them to eat vegetarian food for a few days, do not eat fat, let the serum clear, and then do blood tests on an empty stomach.

Question 6: Do you need an empty stomach before routine blood tests? Routine blood examination is a common examination in physical examination. Through routine blood examination, we can get the information of many organs of the body, including liver, kidney, blood sugar, blood lipid and so on. , and know how much you are at risk of liver disease and fatty liver, and at the same time know information such as body immunity. So what? The following hospital liver disease experts will give you specific answers. ? Generally speaking, blood routine examination needs fasting, and it should be fasting before blood routine examination, but fasting is not as simple as skipping breakfast. The night before the examination, you should avoid eating greasy food, especially after 8 o'clock. If you are still eating supper at 12, you can't guarantee an empty stomach when taking blood. On the morning of the physical examination, you can't drink drinks including juice and milk except boiled water. If you want to make the test results more ideal, you'd better start to be basically vegetarian three days before the test. Why do routine blood tests need an empty stomach? What are the basic benefits of fasting before blood routine examination? According to experts from the hospital's hepatology department, fasting before routine blood examination has the following three advantages: each examination adopts different examination methods and has different normal values. Normal data is obtained by measuring the fasting blood of a large number of normal people. Because the body is in a basal metabolic state on an empty stomach, it is relatively stable and can reflect the real situation of human blood, excluding the influence of food and other factors. The normal value of this method is obtained by statistical processing of many test results. Therefore, we should also carry out fasting blood tests on patients. Only in this way can the examination results be reliable, truly reflect the actual situation of patients and provide valuable evidence for the diagnosis of diseases. After eating, food is chewed by the mouth, digested and absorbed by the gastrointestinal tract, and then transported to various tissues and organs of the whole body by blood. Therefore, some ingredients in food enter the blood, which will increase the concentration of some ingredients in the blood. In this way, the test results may be incorrect. Recommended reading guide "; What kind of people are susceptible to hepatitis C If blood testers eat in the morning, a large number of chylous particles produced after food digestion will be quickly absorbed into the blood, and at this time, the blood becomes turbid, which is medically called fatty blood. Because many blood biochemical tests are judged by the change of specimen color, if the blood is turbid due to chylous particles, it will be difficult for inspectors to observe clearly, which will eventually affect the correctness and reliability of the results. Therefore, fasting blood drawing will not be affected by foreign food and other factors, and can reflect the real physiological situation in the human body. Hospital-ordinary people can freely choose through the above introduction. " Our experts remind us that if we have this disease, we must go to the hospital for examination in time to avoid delaying the illness. If it is convenient, welcome to our hospital for treatment. If you have any other questions, please ask the experts and they will give you patient answers. Recommended reading guide "; What are the causes of hepatitis C?

Question 7: Do you want to draw blood on an empty stomach? Under normal circumstances, liver function, renal function, blood lipid and blood sugar require patients to draw blood on an empty stomach the next morning.

First of all, because the body is in a relatively basic metabolic state on an empty stomach, the influence of factors such as diet can be ruled out, so an empty stomach blood test can reflect the real situation in human blood. Therefore, if fasting blood test is needed for patients, fasting blood must be taken, so that the test results are reliable.

Second, avoid the influence of eating a variety of foods on some components in the blood. After eating, food is digested by the mouth, digested and absorbed by the gastrointestinal tract, and then transported to various tissues and organs by blood. Therefore, some ingredients in food will enter the blood, which will increase the concentration of some ingredients in the blood, thus affecting the accuracy of the test results.

3. If you eat before the blood test in the morning, the top chylous particles produced after food digestion will be quickly absorbed into the blood, and then the blood will be "turbid", which is called "fatty blood" in medicine. Because many blood biochemical tests are judged by the change of specimen color, it is difficult for inspectors to clearly observe whether the blood is turbid due to chylous particles. Especially when measuring blood lipids, "fatty blood" will affect the accuracy of measurement. Therefore, in order to make some blood tests more accurate, it is hoped that patients must follow the doctor's advice.

Question 8: Do blood tests have to be on an empty stomach? Yes, this will make the blood test more accurate