Name | Zhang Xinlan

Unit | Dehong State Traditional Chinese Medicine Hospital Inspection Department

Preface

The emergence of vacuum vascular mining with different anticoagulants has greatly facilitated the various tasks of the inspection department, but the anticoagulant is a double -edged sword. On the one hand In terms of inappropriate anticoagulants selected, severe interference will be caused by some measurement results. In clinical biochemical tests, we most often use serum specimens, which are suitable for most biochemical projects.

Case pass

On May 27, 2022, a specimen sent by the cooperation unit of the foreign hospital to do two pairs of hepatitis B and liver merit at the time. The information of the patients is covered with information. It should be seen that the appearance should be an EDTA-K2 anticoagulant tube. I thought that although there were some results between the plasma and the serum, it should be used, so I would put it on the machine.

The results made below are as follows: ALP is obviously abnormal, and the rest of the projects are basically normal. The same result is the same. The specimen before and after the project is normal, and the current specimen instrument has no abnormal alarm information. He hesitated and issued this report.

The next day, the patient had doubts about the results of ALP and came to consult. In order to confirm whether it is a serious error caused by the type of sampling tube, the information written on the sampling pipe is wiped off, and it is determined that it is an EDTA-K2 anticoagulation tube, and the ALP <2 is reviewed again, which is no different from the results of the day before. With an unwilling heart, I found other patients who have adopted a biochemical tube and EDTA-K2 anticoagulant pipe to compare. The result is confirmed that there is indeed a significant difference between the two, as shown below:

Index (unit U/L)

EDTA-K2 anticoagulation tube

Serum tube

No. 1 sample ALP

<0

52

No. 2 sample ALP

<1

94

No. 3 sample ALP

<0

48

case analysis

After verifying the detection sample and the detection process, after the comparison verification, a series of questions have been poured into my heart, and there are no similar incidents in the normal work. Just staying on a very basic "difference", is the impact of anticoagulants really so great? Check the information with questions.

In the following information in Teacher Tan Yanbo's "Comparison of the results of different blood specimens in the detection of biochemical projects" [1]: As can be seen from the figure, the EDTA-K2 anticoagulation specimen was significantly affected in the ALP results in the liver power project.

So the question is, why does the EDTA-K2 anticoagulant cause ALP to be significantly suppressed? From the comparison of the results of "Different blood samples in the detection of biochemical projects" [2] by Wanli and other teachers, you can still see that EDTA-K2 anticoagulation has a significant inhibitory effect on ALP, as shown below: as shown in the figure below:

And the article explains: The detection value of the EDTA-K2 anticolybing plasma ALP is significantly lower than the measurement values ​​of other groups, showing a significant inhibitory state, and even the individual detection value is zero. This is mainly because the intermediate product in the ALP detection is right Nitro -phenol needs to be transformed into a pyrine structure in an alkaline solution, showing darker yellow and performing color analysis. EDTA produces hydrogen ions during the anticoagulation process, which makes the solution neutral or even acidic. inhibition.

Summary

In 2002, the WHO document "The use of anticoagulants in laboratory examinations" emphasized that using anticoagulants can avoid changes in components in the blood, and the composition in plasma can better reflect the pathological state of patients than serum. In the current laboratory inspection, there are two main problems in the use of countermeasures. One is the test of the project, which regards the detection results of serum and plasma as the same; the other is that the different anticoagulants are neglected Different detection results.

Through this case, there are a few thoughts:

1. Many laboratory blood collection is completed by the nursing unit, and the information management is labeled. The inspectors can only distinguish the types of sampling tube through the color of the vascular hats. It is not easy to remember the type of anticoagulant, such as the heparin lithium and heparin sodium anticoagulation tube shown in the figure below, and the editor of the heparies can always be unable to remember.

2. When there are interns, most interns are involved in centrifugal and capsules, or some large hospital specimens are particularly different and have special centrifugal and capacity. Which one is.

3. If there is a part of the case that the serum tube specimen is not enough, the inspection section cannot be monitored from the general blood conventional tube, or it can only be inferred from some specific projects.

4. One of the report forms in the case is inappropriate, that is, the column of the "specimen type" is not modified. The actual specimen is EDTA-K2 antibody plasma. To the type and results of the specimen type and results.

In summary, the error of our test results often occurs unknowingly, and suddenly finds the lack of knowledge. To discover the errors of various types of errors, we need to continue to learn Strengthen the cultivation of the ability to identify the interference factors.

references:

[1] Tan Yanbo. Comparison of results of different blood specimens in the test of biochemical projects [J]. Clinical test magazine (electronic version), 2018,7 (2): 327-328. [2] Wan Li, Song Juan, Zhang Qinglian.Comparison of the results of different blood samples in the test of biochemical projects [j]. Test medicine and clinical, 2011,08 (8): 947-948,950.