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1. The forcing of a fluid into a vessel, tissue, or cavity.

All supplies used in preparing and administering an injection should be sterile. The caregiver chooses the appropriate syringe size for the volume of fluid to be injected, the appropriate needle gauge for the type of fluid, and the appropriate needle length for the route and site of the administration, considering the amount of muscle and adipose tissue, mobility limitations, and other site-related factors. Hands should be thoroughly cleansed before and after the procedure, and gloves worn if preparing a chemotherapeutic agent. The prescribed dose is accurately measured. An appropriate site is identified by using anatomical landmarks; the area is cleansed with an antiseptic swab (from the center outward), and time is allowed for the antiseptic to evaporate. The needle is inserted at the appropriate angle along the prescribed route. Intradermal injections use a short, fine needle with the opening faced upward; the needle is placed nearly parallel to the surface of the skin and advanced far enough for the injected fluid to make a small bubble under the skin, then carefully removed; pressure that could cause the fluid to leak out onto the skin surface should be avoided. Subcutaneous injections should consist of no more than 1 ml. A short needle should be inserted at a 45° angle, without aspiration, and gentle pressure or no pressure applied to the site after needle removal. Intramuscular injections are made at a 90° angle; after insertion the syringe plunger is aspirated to ensure that no blood returns to prevent accidental injection into a blood vessel. The prescribed medication is injected slowly, then the needle is removed, and pressure is applied to the site with a dry sponge. A Z-track method helps to ensure that the medication remains in the muscle as desired and does not leak back into subcutaneous tissues. When administering an intravenous (IV) injection, the syringe is aspirated and blood obtained to be certain the needle is in the vein. When removing a needle after administering an IV injection directly into the vein, the caregiver lessens the chance of bleeding into soft tissue by applying firm pressure with a dry sponge while elevating the site above the heart for several minutes. However, the vast majority of intravenous injections are administered through an IV catheter or an IV fluid port with a needle or needleless device. Pressure is not applied when removing this device. The needle should not be recapped; both the needle and syringe should be disposed in a “sharps” container according to protocol. The injection time and site, any untoward responses to the injection, desired effects, and adverse reactions to the particular drug injected are recorded.

2. A solution introduced in this manner.
3. The state of being injected; congestion. SEE TABLE: Unsafe Injection Practices
Unsafe Injection Practices
1. Drawing up the wrong medication for the wrong patient or for an unapproved indication
2. Wrong dose or dosing interval
3. Wrong body part or route of administration (IV versus IM or subcutaneous)
4. Reuse of a syringe, intravenous solution bag, medication vial, or needle on multiple patients
5. Sharing of injection equipment by multiple patients, e.g., of insulin pen injectors or of illicit drugs
6. Contamination of medication vials before or during use (risk of bacterial, fungal, or viral contamination)
7. Nonsterile technique during injection
8. Mishandling of medications, e.g., inadequate refrigeration or dilution

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