Having blood in a lagging needle the next day is mostly unaffected. Having blood inside the lagging needle and the blood not clotting the next day is usually of no consequence. The lagopharyngeal needle must be sealed with a heparin cap to avoid clotting of the blood in the lagopharyngeal needle. After the first day of infusion, the lagopharyngeal needle will be sealed to avoid blood reflux and coagulation of blood in the lagopharyngeal needle. If there is a small amount of blood in the lagopharyngeal needle memory, the blood reflux will not usually have an effect. If there is a small amount of blood in the needle, it will not affect the blood. This is because the needle has been anticoagulated with heparin to keep the blood in a normal state when the tube is sealed. The needle can continue to be used the next day. The needle can be left in the vein for 3 to 5 days. When the needle is no longer being used for infusion, the tube should be sealed with a heparin cap to prevent blood return.