Views:2 Author:Site Editor Publish Time: 2021-04-15 Origin:Site
The vacuum blood collection tube is a one-time negative pressure vacuum glass tube that can realize quantitative blood collection and needs to be used in conjunction with a venous blood collection needle. With the popularization of vacuum blood collection tube applications, it has brought convenience to hospitals. Because of its easy operation, clean, safe, accurate and reliable, it has been used more and more clinically. However, in the process of clinical use, various problems occur from time to time, which affect the smooth collection of specimens. The following points are several issues that should be paid attention to in the use of vacuum blood collection tubes:
1. The patient should relax when taking blood, and the environment should be warm to prevent venous contracture. The strapping time should not be too long, and it is forbidden to tap the arm, otherwise it may cause local blood concentration or activate the coagulation system. After making a fist for 2 minutes, the serum concentration of potassium can increase by 1.0 to 1.5 mmol/L. Blood collection should hit the nail on the head to prevent tissue damage and exogenous coagulation factors entering the test tube and affecting the test results.
2. The blood volume of the sample collection should be sufficient. The presence of vacuum can easily rupture the blood cell. If the blood sample is not used enough, the bottle stopper should be opened for a while after blood collection. The ratio of blood to anticoagulant must be precise. The absolute content of anticoagulant in blood samples can change the plasma calcium ion concentration and affect the results of the experiment. The higher the absolute concentration of calcium, the shorter the coagulation time of PT and APTT.
3. When using blood collection tubes containing coagulant or separating gel, be sure to wait for the blood to coagulate before centrifugation, otherwise clots are likely to appear in the serum and cause the instrument to block the holes. Serum tube (red) generally needs to wait for 0.5～1h, and for coagulant containing coagulant, wait for 10～30 min. Heparin tube (green) can be centrifuged to separate plasma after mixing and anticoagulation. Separating rubber tube (yellow) 5～10 Centrifuge after min.
4. The recommended blood collection sequence is coagulation vessel (serum tube) → sodium citrate tube → heparin or EDTA tube → potassium oxalate 2 sodium fluoride tube → erythrocyte sedimentation tube. The main reason is that the first tube often contains tissue fluid, which is easy to cause coagulation and is not suitable for blood coagulation determination.
5. After the blood collection is completed, first remove the back test tube from the needle holder, and then pull out the needle from the vein. If there is blood leakage, in addition to the loose installation of the needle, it is more common in the hemostatic protective sleeve or the hemostatic sheath The rebound is too slow or can not rebound in place.
6. Due to the relatively large negative pressure of the vacuum tube, at the beginning of blood collection, the blood flows into the bottom of the tube at a fast speed, red blood cells collide with each other to cause rupture, and clinical hemolysis is occasionally seen. In this regard, when collecting blood samples, tilt the side needle of the two-way blood collection needle to make it close to the side wall of the blood collection tube, and the blood slowly flows down the tube wall to avoid direct impact of red blood cells to cause rupture and form hemolysis.
7. Due to the loosening of the latex sheath at the end of the blood collection tube of the two-way lancet or the needle piercing the latex sheath, the two-way lancet is not tightly sealed. During venipuncture, blood leaks along the end of the blood collection tube of the bidirectional blood collection needle. In this regard, check and tighten the latex sheath before blood sampling, and re-fit the needle if the needle is punctured to maintain its airtightness.
8. Because the puncture needle is stuck to the blood vessel wall or there is no negative pressure in the blood collection tube, the blood inflow is not smooth. Under the premise of ensuring the success of venipuncture, the direction of the needle can be adjusted until the blood flows into the blood collection tube. If it is invalid, replace the blood collection tube.
9. Due to the insufficient negative pressure in the blood collection tube, the blood collection volume is insufficient. The syringe needle can be pierced from the rubber stopper of the blood collection tube, and the air in the blood collection tube can be sucked to form a negative pressure until the blood sample is collected. The blood collection tube can be directly replaced when the original blood volume is low.
The above are the problems that are prone to occur during the use of vacuum blood collection tubes. Therefore, we must pay attention to these problems when using vacuum blood collection tubes. As long as these problems are solved, the vacuum blood collection tube can bring us more accurate, more convenient and faster results.