Blood test for sugar from a vein: norm and other indicators

Elevated blood sugar levels indicate severe disruption to the body. Most often, it is the first sign of the development of diabetes in humans. This dangerous disease leads to irreversible changes in the body, so the successful treatment of diabetes depends on timely diagnosis.

The main method of detecting diabetes is a blood test for sugar. Typically, capillary blood taken from a patient’s finger is used to perform this laboratory test. But sometimes more accurate results of this medical test can be obtained by analyzing the composition of venous blood.

The results of the study of venous and capillary blood can be very different from each other. Blood from a vein has a thicker consistency and is more saturated with various substances, including glucose. Therefore, the level of sugar in venous blood is always slightly higher than in capillary blood.

Therefore, in order to properly decipher the results of the analysis, one should know what the normal blood sugar is from the vein and what level of glucose indicates the onset of diabetes. This is especially important in cases of suspected diabetes mellitus type 1, as it tends to develop very rapidly.

Normal blood sugar from a vein

Normal blood sugar is an important indicator of physical health, especially in people in adulthood and old age. After a 40-year mark, a person has a significantly increased risk of developing type 2 diabetes, which is often a consequence of an unhealthy lifestyle.

For this reason, it is very important to be tested for blood sugar at the age of 40-50 years in order to identify the disease in time and begin the necessary treatment. This will help to avoid the development of severe complications, which are often identified on the background of diabetes.

The most common type of diagnosis is fasting blood. For this test, blood for vein sugar is usually taken in the morning before meals. This analysis shows how the human body absorbs glucose, which is produced by liver cells between meals.

There is another type of diagnosis of diabetes. It involves a blood sugar test after the patient has taken a glucose solution. This test helps determine the tolerance of internal tissues to glucose and in the case of a sharp increase in blood sugar, diagnose insulin resistance.

The sugar rate for blood sampling from a vein is, on average, 12% higher than with a finger blood test. Therefore, they should not be frightened if the results of this diagnostics will exceed the standard limits of 3.3 - 5.5 mmol / l.

Speaking about what the norm of blood sugar from a vein should be in a healthy person, it should be noted that there are two indicators - on an empty stomach and after eating. Both of these values ​​are needed to make a final diagnosis of diabetes mellitus.

Fasting blood test:

  1. The limits of normal range from 3.5 to 6.1 mmol / l;
  2. The presence of prediabetes is detected at rates from 6.1 to 7 mmol / l;
  3. The diagnosis of diabetes is made at a sugar level above 7 mmol / l.

Blood test after a meal:

  1. Indicators are considered normal to 7.8 mmol / l;
  2. Prediabetes is detected when the sugar level is from 7.8 to 11.1 mmol / l;
  3. Diabetes is diagnosed at rates above 11.1 mmol / l.

Symptoms of diabetes

Raising the level of sugar in the venous blood is just one of the many signs of diabetes. This chronic disease manifests itself as a whole complex of symptoms that all people predisposed to this disease need to know.

Symptoms of diabetes can manifest themselves in different ways depending on the type of disease. So type 1 diabetes develops very quickly and proceeds with a pronounced manifestation of all the symptoms. This form of diabetes after a few months can lead to the emergence of dangerous complications.

Diabetes of the second type develops much more slowly and can be almost asymptomatic for a long time. Therefore, the patient is often able to identify insulin-independent diabetes only in the study of blood for sugar.

Symptoms of high blood sugar:

  • Chronic fatigue, weakness in the whole body;
  • Frequent pains in the head;
  • Drastic weight loss;
  • Constant feeling of hunger;
  • Great thirst, which can be quenched only for a short period of time;
  • Excessive urination, the patient may even experience bed-wetting;
  • Any wounds and cuts heal for a very long time and tend to inflame;
  • The appearance of various skin diseases, especially dermatitis;
  • The deterioration of the immune system, frequent colds;
  • Pruritus, especially in the hips and groin;
  • Decreased sexual activity in men;
  • Frequent thrush in women;
  • Decreased visual acuity.

Low blood glucose from a vein

Everyone knows what the danger to human health is a high level of sugar in the blood. However, few people know that low concentration of glucose in venous blood can cause the body no less harm. Hypoglycemia (low blood sugar) causes severe damage to the nervous system and can cause irreversible changes in the brain.

A low concentration of blood glucose from a vein is characteristic of liver diseases, severe poisoning, nerve ailments and serious metabolic disorders. In addition, this condition may be due to alcohol consumption and prolonged fasting in diabetes.

If time does not stop an attack of hypoglycemia, then the patient may lose consciousness and fall into a hypoglycemic coma. In this case, only emergency hospitalization can save him from death. Therefore, it is very important to provide the patient with all the necessary help while he is still conscious. To do this, he must be given a glucose solution, fruit juice, or any other sweet drink.

Low blood sugar from vein indicators and symptoms:

  1. From 3.5 to 2.9 mmol / l - the patient has sweating, heart palpitations and severe hunger;
  2. From 2.8 to 2 mmol / l - the patient has inadequate behavior and temporary mental disorder. When glucose drops to this level, a person increases irritability and aggression, he may commit rash acts and even pose a danger to himself and others;
  3. From 2 to 1.7 mmol / l - violation of the nervous system takes more severe forms. The patient has a complete lack of vitality, he becomes very sluggish and apathetic. With this level of glucose, a person stops responding to external stimuli, and does not show any interest in the outside world. Sometimes he is not even able to say his name;
  4. From 1.7 to 1 mmol / l - such a deviation from normal values ​​is very dangerous for the patient. At this moment, the patient has severe convulsions and serious disturbances in the functioning of the brain, as can be seen on the electroencephalogram. If in such a situation not to provide emergency medical care to a person, he may fall into a heavy glycemic coma.

From 1 mmol / l and below - this is the maximum level of glucose. With it, the patient falls into a deep coma, which leads to the death of the brain and the subsequent death of the patient.

How to donate blood for analysis

In order for the results of diabetes diagnosis to be as accurate as possible, it is necessary to know how to donate blood from a vein to sugar. If you do not follow all the recommendations of physicians, then the results of this test will not reflect the real state of health of the patient, and, therefore, will not help to assign him the correct treatment.

It is important to understand that when examining blood, the rate of sugar may deviate noticeably if the patient had eaten too much sweets the day before or had suffered a lot of emotional stress. In addition, in the analysis of blood sugar levels from a vein, drinking alcohol or smoking cigarettes can play a negative role.

Also, the level of glucose in the blood from a vein, the norm of which is extremely sensitive to any physical activity, may be affected by sports, doing physical work, or even brisk walking.

How to prepare for the analysis of blood from a vein for sugar:

  • The last meal should be no later than 8 hours prior to analysis;
  • During this period of time you can not drink any drinks, except pure water. This rule applies especially to tea and coffee with sugar, as well as sugary carbonated drinks;
  • Before diagnosing, it is forbidden to brush your teeth with toothpaste or chew gum in the morning;
  • The day before the test, you should refuse to take any medication. If, due to poor health, the patient cannot stop taking the medication, then he needs to tell the doctors about it;
  • The day before the analysis can not take alcoholic beverages;
  • Before diagnosing diabetes, smoking cigarettes is prohibited;
  • 24 hours before the blood test, you need to abandon sports and other types of physical activity.

In no case can these rules be ignored, since they are essential for conducting an objective blood glucose test. Only compliance with all medical recommendations will ensure accurate results and the subsequent formulation of the correct diagnosis.

About normal blood glucose is described in the video in this article.

Watch the video: Diabetic Emergencies (February 2020).