Application of heparin lithium blood collection tube in blood samples of patients with multiple myeloma

Heparin is a mucopolysaccharide containing sulfuric acid group, with a relative molecular weight of 15× 103 and a strong negative charge. Commonly used sodium, potassium and lithium salts, 100 ~ 125 U/mg can make 5 ~ 10 ml blood not coagulate. Heparin is an excellent anticoagulant, which has little interference with blood components and does not cause hemolysis, and is suitable for biochemical determination [1]. This is very important for daily clinical laboratory work, especially in emergency rescue. Because anticoagulant samples can be directly centrifuged without pre-incubation, it can save a lot of time, provide test results to clinic as soon as possible, and win valuable time for saving patients' lives. According to the traditional theory, heparin anticoagulated plasma has little influence on biochemical detection, but in fact, the author found that some items have influence in his work, so two samples with different additives in the same sample were compared in electrolyte determination and statistically analyzed by Excel software. The results are reported as follows. 1 materials and methods

1. 1 sample source The sample comes from the outpatient physical examination of our hospital.

1.2 The instruments and reagents are AC980 1 electrolyte analyzer and its supporting reagents, and heparin lithium vacuum blood collection tube (provided by Chengdu Xinjin Shifeng Medical Equipment Co., Ltd.).

Step 1.3 40 samples of 20 people were collected with heparin lithium vacuum blood collection tube and common blood collection tube without any anticoagulant. After 10min, they were centrifuged at 4000 r/min (TDZ5 ‐ WS Centrifuge, Changsha Xiangzhi Centrifuge Co., Ltd.

), two samples of the same patient were detected on AC980 1 and recorded.

1.4 statistical processing: Excel2003 software was used for data analysis, and the paired data were compared by T-test, P < 0.05 was statistically significant.

Two samples of 20 people were tested for electrolytes. From the table 1, it can be seen that the electrolyte results measured by heparin lithium anticoagulant plasma are statistically significant, but the blood sodium and blood chlorine levels are not statistically significant.

The results of this study show that heparin has no effect on the determination of serum sodium and serum chlorine compared with serum without anticoagulant, which is very different from that reported by Qin Lihua [2]. Why the same experiment will have different results needs to be further observed by increasing the sample size. For blood potassium, the difference was about 0.30 mmol/L, and the difference was statistically significant (P < 0.05). This is consistent with the difference of 0.38 mmol/L between plasma potassium and serum potassium reported by Wang Jianqiong and others, indicating that heparin lithium anticoagulation has obvious influence on potassium level in electrolyte determination. From the etiological analysis, it may be that heparin and potassium produce heparin potassium, which affects the determination of potassium by ion-selective electrode and leads to low blood potassium. At the same time, for serum samples, due to the destruction of platelets during coagulation, potassium ions in platelets (the concentration of which is much higher than that of plasma potassium) are released into the blood, which makes serum potassium higher than plasma potassium, and the increase is positively related to the number of platelets. It is reported that the serum potassium concentration is about 0.15 ~ 0.18 mmol/l [4 ‐ 6] higher than the plasma potassium concentration every time platelets increase. However, according to the author's daily clinical experience, despite the influence of platelet destruction, the determination of serum potassium is still better than that of plasma potassium, mainly because serum potassium has no influence of heparin, and serum is widely used as a specimen in routine biochemical tests and analysis in China, and most of the existing reference values come from serum, although serum is not necessarily a reliable reference system [8]. If reported by plasma potassium,