Vessel slip is the movement of blood vessels in the subcutaneous wandering space for their normal position, which happens to most people. The so-called blood vessel slippage is that the nurse is difficult to fix the blood vessel during operation, so that the blood vessel slides to one side, causing certain difficulties for puncture. If the upper end of the blood vessel is fixed and the lower end of the blood vessel is fixed, then the blood vessel is not easy to be shifted when the puncture is carried out again. Many people have this situation, generally thick blood vessels or loose skin of the elderly will shift amplitude, but this is not a pathological phenomenon, when the blood pumping with a good with the fist tense skin, more conducive to puncture. The situation can be regarded as a normal physiological phenomenon of the body, without excessive worry.