With complicated forms of various diseases, formore accurate diagnosis and identification of the causes of their appearance may require blood from the vein in an amount of up to 10 ml. The results of the research depend on the quality of the blood sampling procedure.
If a laboratory technician can take the capillary blood, thenthe collection of blood from the vein should be performed by a qualified nurse, in a sterile procedural room, using a special instrument.
It is important that the patient is prepared for the surrender of blood,because there are a number of factors that can adversely affect the outcome of the study. Physical overstrain before the procedure should be avoided (fast walking, running, climbing stairs), refuse to eat before research, do not smoke and do not drink alcohol, keep emotional calm.
Before taking blood from the vein, the medical staffis obliged to give the patient under examination a 15-minute rest. Immediately during the procedure, the patient should sit, and the seriously ill patient may lie. If the patient used food, smoked or drank alcoholic drinks, the delivery of tests can be postponed to a different date.
It is most convenient to take blood from the veins of the forearm,since here they are located on the surface and are clearly visible. Here the following veins can be used: external superficial, ulnar, medial superficial, radial, median vein of elbow, internal superficial.
The veins are differently fixed in the tissues of the body,so blood is best taken from less moving vessels, as they are more convenient for piercing with a needle. These blood vessels include the median vein of the elbow and the outer surface of the elbow.
In the absence of a full-fledged experience, taking blood should not be done from the inner superficial vein, since next to it is a worm and an artery. An inaccurate injection can harm a patient.
If the veins of the ulnar fold are not visible enough (for example, in obese people), it is possible to draw blood from the venous vessels of the back surface of the hands, as well as the popliteal cavity.
Infants take blood from the veins located on thetemples. When the child screams, they swell significantly, which makes it safer to make a puncture with a needle. Also, blood from the vein can be taken from the child's heel.
It should be avoided to take a fence in placeslocation of scars, hematomas, from venous vessels used for transfusion of medical solutions. In patients with diabetes, with violation of peripheral blood flow, angiopathy, do not take blood from the leg veins.
The procedure is carried out in disposable rubber gloves. Otherwise, gloves should be pre-treated with medical alcohol.
For the collection of blood from the vein, the followingtools and accessories: vacuumers (disposable plastic blood sampling systems), disposable syringes and needles with a cross-sectional diameter of 0.55-0.65 mm, an elastic tourniquet, a test tube, sterile rubber gloves, cotton balls moistened with alcohol.
Taking blood from the vein is as follows:
A plait is applied to the middle third of the shoulder to stop blood flow.
The place of the elbow fold is processed sequentially with two balls of cotton wool, previously moistened with alcohol. The patient at this time clenches and unclench the fist.
The most complete vein is found and fixed by stretching the skin. The patient should squeeze his hand into a fist.
Firmly holding the tip of the needle with a cut up and parallel to the skin, it is necessary to pierce the vein and gently, along the vessel, insert the needle a third of the length.
To the needle cannula substitute the tube and release the blood in the right quantity.
Remove the harness. The patient should unclench the fist.
The needle is removed, and the puncture site is covered with a cotton ball.
The patient should bend at the elbow joint arm, to press the vein until the bleeding stops.
To the test tube, in which the blood from the vein is located, it is necessary to attach a direction.
