Since the creation of vacuum blood collection tubes in 1937, vacuum blood collection test tubes have become increasingly common, gradually replacing the method of syringe blood collection, which has increasingly standardized blood collection skills and improved the quality and speed of testing specimens. In 2004, it was reported that due to the change in the pressure difference between the internal pressure of the vacuum blood collection tube and the intravascular pressure, the adopted blood has the ability to flow back into the blood vessel and has the risk of infection. It has been stated that Serratia marcescens was detected from some vacuum blood collection tubes. If there is a risk of infection due to blood reflux, the safer blood collection skills have attracted attention from all walks of life. This article describes how to prevent backflow of blood flow:
Why it can cause blood backflow: The "vacuum" of vacuum blood collection tube refers to the condition of no air at all, which is lower than atmospheric pressure. The pressure increase (negative pressure) of the vacuum blood collection tube is set according to the blood collection volume.
When the cuff is tightly pressed, the intravascular pressure rises-after the blood collection needle intervenes in the elbow vein, blood flows into the vacuum blood collection tube under negative pressure. After the pre-negative negative pressure is exhausted, the blood collection is completed, at this moment, the intravascular pressure = vacuum intravascular collection! Blood collection is ended because the blood pressure in the blood vessel is lowered quickly than normal pressure after removing the driving belt. At this moment, the blood pressure is less than the blood pressure in the blood collection tube, and there is a risk that the pumped blood can return to the blood vessel.
Blood collection method to prevent blood backflow: remove blood drive belt during blood collection. The adopted blood prevents some spitting from touching the lancet. Do n’t remove the lancet during blood collection. The adopted blood prevents some spitting from the lancet (make the tube seat down during blood collection, preventing some spitting from the lancet from touching the blood ), This can be prevented.