The preparation of heparin sealant is usually 100 ml salt water with half a branch of heparin, one heparin is 25,000 units. Of heparin sodium sealing tube fluid density is 12500 units per 100 milliliters, heparin liquid seal tube is mainly used for deep vein puncture wash pipe and tube, sealing of indwelling needle puncture after losing the liquid also requires the use of heparin sodium sealing tube, long-term indwelling PICC tube more need of heparin sodium sealing liquid seal tube, the main effect of heparin sodium sealing tube fluid is to prevent lien and other indwelling needle puncture blood clots in the ducts.