What does the blood test check?

A routine blood test is a relatively common blood test item. Blood is composed of two components: liquid and tangible cells. The process of a routine blood test includes red blood cell tests, white blood cell tests, and platelet tests. Through such tests, some disease problems, some inflammatory problems, etc. can be discovered. Therefore, a routine blood test is very important.

Precautions

1. Before inspection:

(1) Do not eat greasy or high-protein foods and avoid drinking large amounts of alcohol the day before blood collection. The alcohol content in the blood will directly affect the test results.

(2) You should fast for 12 hours starting at 8pm the day before the physical examination to avoid affecting the test results.

(3) When drawing blood, you should relax to avoid blood vessel constriction due to fear, which will increase the difficulty of blood collection.

2. After inspection:

(1) After drawing blood, apply local pressure on the needle hole for 3-5 minutes to stop the bleeding. Note: Do not rub to avoid causing subcutaneous hematoma.

(2) The pressing time should be sufficient. The clotting time varies from person to person, and some people need a little longer to clot. Therefore, if you stop applying pressure immediately when the surface of the skin seems to be not bleeding, the bleeding may not stop completely, and the blood may seep into the subcutaneous layer, causing bruises. Therefore, pressing for a longer time can completely stop the bleeding. If there is a tendency of bleeding, the pressing time should be prolonged.

(3) If you experience symptoms of needle phobia such as dizziness, blurred vision, fatigue, etc. after blood draw, you should lie down immediately and drink a small amount of sugar water. Wait until the symptoms are relieved before undergoing a physical examination.

(4) If local bruising occurs, apply a warm towel for 24 hours to promote absorption.

Inspection process

Venous blood sampling usually uses superficial veins located on the body surface, usually the elbow vein, the back of the hand vein, the medial ankle vein or the femoral vein. The antecubital vein is the preferred blood collection site for most people (except infants and young children). The blood vessels here are generally more obvious, the pain is lighter, and the operation is convenient and easy. In children, blood can be drawn from the external jugular vein. The femoral vein is selected next.

method:

(1) Prepare all the necessary materials, label the specimen containers, and after verifying that they are correct, explain the procedure to the patient to gain their cooperation. Expose the patient's arm, select a vein, tie a tourniquet about 4-6 cm above the venous puncture site, and ask the patient to clench his fist to make the vein full and visible.

(2) Disinfect the skin routinely and wait for it to dry.

(3) Below the puncture site, use the left thumb to tighten the skin and fix the vein. Hold the syringe in the right hand with the needle beveled upward at an angle of 15 to 30 degrees to the skin. Insert the needle into the subcutaneous tissue above or beside the vein. Then insert the needle into the vein along the direction of the vein. After seeing the blood return, slightly flatten the needle and move it forward to fix it. When the required amount of blood is drawn, loosen the tourniquet, ask the patient to relax his fist, press the puncture point with a dry cotton swab, quickly remove the needle, and flex the patient's forearm for a moment.

(4) Remove the needle and slowly inject the blood into the container along the tube wall. Do not inject the foam to avoid hemolysis. When glass beads are placed in the container, it should be shaken quickly to remove fibrinogen; if it is an anticoagulant test tube, it should be rotated and rubbed in both hands to prevent coagulation; if it is a dry test tube, it should not be shaken; if it is a liquid culture medium, the blood and culture fluid should be mixed evenly, and the bottle mouth should be disinfected with flame before and after the blood is injected into the culture bottle, and be careful not to let the bottle stopper contact the blood.

The amount of blood drawn is determined by the content of the test and the number of items, usually around 5 ml.