PREPARATION OF THE MATERIALS FOR AN INJECTION Ovidiu Fabian, Emilia ăţ Learning objectives What you should know What is an injection What are the parenteral routes of administration of drugs; what types of injections are there What are the advantages of parenteral drug administration What is a syringe; which are the parts of the syringe and needle What information should be looked for in the prescription / medical indication What important information should be looked for on the syringe package What information should be sought on the package of the medicine to be administered What materials are necessary for the injection procedure The technique of dissolving medication and aspirating it into the syringe What is a container for sharp objects What you should do Choose the right materials for an injection Check the identity of the patient that is about to have the injection Check the ’medication Open the packaging for the syringe / needle Attach the needle to the syringe; loosen and remove the needle sheath Open a vial and aspire the contents into the syringe Dissolve a medicinal powder in the vial and absorb the contents into the syringe Place the filled syringe into a position that is convenient to use Disinfect the place of the future injection Keep material sterility throughout the entire procedure Discharge the needle into the container for sharp objects Definition Injection is a procedure by which a drug substance is introduced into tissues using a special needle and a syringe. Drug administration through injections is called parenteral administration (bypass digestive tract). The ways of parenteral drug administration are: Intradermal route (intradermal injection) Hypodermic route (subcutaneous),(subcutaneous injection) Intramuscular route (intramuscular injection) Intravenous route (intravenous injection and infusion) Intra-arterial route (intra-arterial injection) Intraosseous route (intraosseous injection and infusion) Indication An injection can be made for therapeutic or diagnostic purposes o For example administration of an intramuscular or intravenous antibiotic is for therapeutic purposes o Testing of antituberculous immunity (so-called intradermally in tuberculin) is done by an intradermal injection (diagnostic purpose). Some drugs may be administered both orally and parenterally. Sometimes, however, the oral route is not available: o Patients with digestive stasis (as is the case with most patients in the first hours / days after surgery) o Patients who throw up o Patients in coma / uncooperative / oro-tracheal catheterization o Patients with facial trauma Some substances can not be given orally (enterally) because they are digested in the digestive tract, inactivated in the liver or have hepatotoxic effects. Even if it involves minor trauma, parenteral drug administration has several advantages: o Precise dosing of the administered substance o Absorption and bioavailability of the substance are virtually complete (100%) o Quick action o Allows administration of medication even when the oral route is not usable o Allows the administration of substances that would be digested in the digestive tract, would be inactivated in the liver or would have liver side effects. Contraindications . There are no contraindications to injections as a procedure itself. The choice of medication should take into account possible allergies, side effects. Anatomical regions with infections, scars, hematoma, etc. Will be avoided as places for administration. Description of the syringe and needle The syringe is a single use disposable plastic instrument (not re-sterilized) used for Figure 1. Syringe parental drug administration. It consists of a plastic tube (barrel) and a plunger. The needle attaches to the syringe through which the medication is inserted into the tissue. The syringe body has, at one end, a truncated cone extension - the adapter for the needle. The adapter can be located centrally or eccentrically. At the other end, the syringe body has two lateral extensions useful for securing the Figure 2. Parts of the syringe syringe while pushing the plunger. There are syringes with different volumes (1, 2, 5, 10, 20, 50 ml). A scale (milliliters or tenths of milliliter) is marked on the barrel to allow a precise amount of substance to be introduced into the syringe. The plunger is perfectly sealed on the inner diameter of the barrel. Both filling and emptying the syringe is done with the help of the plunger. The syringe needle is a skewed steel tube at one end and has at Figure 3. Needle for injection its other end a funnel-shaped plastic that allows attachment to the syringe. The oblique cut tip of the needle is called bevel. The needle is delivered in the same package as the syringe or is packaged separately. It is covered with a plastic sheath. Figure 4. The needle cover(sheath) of the needle Needles are of different thicknesses and lengths, which are noted on the packaging. The thickness of the needle is expressed in the Gauge scale; The higher the number G, the smaller the needle. Needles are used between 14 G and 30 G. The syringes and needles are delivered in a sealed package that keeps them sterile. The packaging consists of a wrinkled sheet of paper and a transparent plastic sheet bonded together; Sometimes they are only sealed in transparent plastic. Only syringes with intact packaging may be used; those whose packaging is damaged can no longer be considered as sterile, so they are unusable. On the packaging is indicated by an arrow (triangle) the place where to open. For some syringes, specific names are used: tuberculin syringe, insulin syringe, Guyon syringe, pre-filled syringe (syringe-vial). Tuberculin syringe Is a small volume syringe Figure 5. Tuberculin syringe (1 ml) and a small diameter, graded in milliliters, with a needle of 25-30G, suitable for administration of small but precise quantities of the substance – for example: medication administered to the newborn or for tuberculin intradermosis for which it was conceived. Insulin syringe ’s also a small Figure 6. Insulin syringe volume (1 ml) thin needle syringe, graded in insulin units; it is used for subcutaneous administration of insulin. Guyon Syringe It is a large volume sy- ringe (50-60 ml); The ori- Figure 7. Guyon Syringe ginal Guyon syringe has a handle made up of 2 rings; With the generalization of single use syringes, its shape has been simplified and the appearance of a typical syringe, but it has a larger volume. Pre-filled syringe Some medi- cines are de- livered in Figure 8. Pre-filled syringe (syringe-vial) sterile syringes, with accurate dose (marked on the package) ready for use. Some syringes are provided with needle cover systems after use, which prevent injury and transmission of potential pathology through the syringe. Some important information is noted on the packaging: Volume of the syringe (in milliliters) - important for choosing the right syringe depending on the type injection: o For intradermal injections: syringes of up to 1 ml o For subcutaneous injections: 1 ml syringes o For intramuscular injections: syringes of 2 - 5 ml o For intravenous injections: syringes of 10 - 20 ml Needle size - important for choosing the right needle depending on the type of injection: o 18-19 G: for geting the medication into the syringe o 20-21 G: for intramuscular and intravenous injections o 25-30 G: for intradermal and hypodermic injections (subcutaneous) Shelf life - only syringes / needles are used that are within viability Stages of an injection Preparation of the syringe; Preparation of the injecting area: choice of the injection area – depending on the type of injection and disinfection of the skin; The injection itself (puncture, medication introduction, needle removal): the technique differs according to the type of injection. Drugs to be administered Parenteral medicines are delivered either as a solution (usually in ampoules / vials) or in powder form (usually packed in bottles). The vials have a circle or a point Figure 9. Vial and ampoule in the neck. These markers are useful for breaking the neck of the vial. The vials that have a circle are held in any position. The vials having a point are held in such a way that the point is in front of the person that is opening the vial, and the neck of the ampoule is inverted in the Figure 10. Markers opposite direction. for vial opening: The bottles are provided with a plastic point or line or metal cap and a rubber sealing plug that is pierced with the syringe needle to dissolve and aspire the substance. The plug is usually provided with 2 slots allowing the needle to be seen in the vial. Figure 11. The bottles are provided In the case of solutions only aspiring into with a rubber stopper the syringe is necessary; In the case of powders, the substance must first be dissolved in physiological serum or (less commonly) sterile distilled water; Some drugs come with specific solvent. The labeling on vials or bottles must be checked for: o Substance name - this verification should be done systematically to avoid any confusion; we never have to rely solely on the appearance of the packaging (there are medicines with similar packaging); o The amount of substance contained - usually there is the quantity for a single administration in the vial / bottle, but there are cases where there are doses for multiple administrations; o The expiration date. Necessary materials Syringe and needle - of the right size A thick needle (18 G) for suction can be used The administered drug: vial (dissolved drug) or bottle (powder to be dissolved) + a solvent vial (physiological serum) 2 alcohol pads or a cotton pads with alcohol. Syringe preparation techniquening Washing of hands Place the necessary materials on a table at hand Check the identity of the patient receiving the medication Verify the medication: o The substance (confirmation that the prepared substance is the one indicated in the prescription), o Dose, o Expiration date.