Take venous blood for blood test. Except for special items, venous blood testing generally requires drawing blood in the morning. Try to minimize exercise before drawing blood. No food, no breakfast, an empty stomach, a small amount of water, except for some drugs that must be taken on time. Otherwise it will interfere with some experimental results.

The amount of blood drawn depends on the test content and the number of items. The amount of blood drawn is generally 2-20 ml, and it will not exceed 50 ml at most. Many health checks depend on blood analysis, so blood drawing is an important part of health checks.

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Precautions for blood drawing:

1. Immediately after blood drawing, compress the puncture site with a sterilized dry cotton piece, and locally press the needle hole and the area two centimeters upward from the needle entrance for 3-5 minutes to stop bleeding. Don't rub it to avoid subcutaneous hematoma. After 24 hours, try to keep the blood drawing arm clean and sanitary, and don't take a bath or sauna.

2, the time to measure blood pressure should be sufficient. The coagulation time varies from person to person, and some people need a little longer to coagulate. Therefore, when there seems to be no bleeding on the surface of the skin, the compression will stop immediately, and blood may seep out of the skin, resulting in bruising due to incomplete hemostasis. So it takes a long time to stop bleeding completely.

3. Rest after blood drawing 15 minutes. /kloc-it is best not to move, sit still or lie down for 0/5 minutes. If you have dizziness, dizziness, fatigue and other symptoms, you should immediately lie down and drink a small amount of sugar water, and then have a physical examination after the symptoms are relieved.

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