Is the infusion needle too small to be slow?

If the needle used is smaller or the patient's vein is thinner, the flow rate of liquid medicine will become slower, thus prolonging the infusion time. When the weather is cold, the patient's venous blood vessels are easy to contract, and the slow reflux speed leads to the slow injection speed of drugs. If it is found that the needle has penetrated the skin, but the drug is not dripping, it is necessary to report to the nurse in time and ask for re-puncture.