To administer into a vein.
An injection of liquid into a vein, e.g. for the fast release of a drug.
Hypodermic injection into a vein to instill a fluid, withdraw blood, or begin a blood transfusion or intravenous feeding.
The injection into a vein or, more commonly, into an intravenous catheter of drugs, electrolytes, or fluids. The insertion of a needle directly into a vein (rarely necessary) requires a degree of skill that is easily obtained if proper instruction is obtained. The vein may be distended by applying a tourniquet with sufficient pressure to stop venous return but not arterial flow. The tourniquet is applied several inches above the injection site. If the patient does not have vascular collapse, the arterial pulse can be palpated; if not, the tourniquet is too tight. Heat applied to the area for 15 min before starting the injection will also help distend the vessels. The use of a needle attached to a 5- or 10-ml syringe will greatly facilitate controlling the course of the needle. It is best to insert the needle into the vein with the bevel side facing out and then, after the needle is in the vein, to rotate it so that the bevel is face in. There will be resistance as the needle goes through one side of the vein wall. The vein should be entered with the needle making only a narrow angle with the long axis of the vein. This will help to prevent pushing the needle completely through the vein.