Fonte: Madeline Lassche, MSNEd, RN e Katie Baraki, MSN, RN, College of Nursing, University of Utah, UT
Injeções intramusculares (IM) depositam medicamentos profundamente no tecido muscular. Uma vez que as fibras musculares são bem perfundadas, esta rota de administração proporciona absorção rápida da medicação e permite a administração de volumes relativamente grandes. Os músculos esqueléticos têm menos nervos sensoriais de dor do que o tecido subcutâneo, o que permite a administração menos dolorosa de drogas irritantes (por exemplo, clororomazina, um antipsicótico). As injeções de IM são recomendadas para pacientes incapazes de tomar medicamentos orais e para pacientes não cooperativos. Alguns exemplos de medicamentos que são comumente entregues por injeções de IM incluem antibióticos, hormônios e vacinas.
Como em qualquer outra via de administração, o enfermeiro deve considerar se a medicação é adequada, dadas as condições médicas, alergias e o estado clínico atual do paciente. Além disso, especificamente para injeções de IM, é importante avaliar a massa muscular do paciente para determinar o tamanho adequado da agulha. Além disso, se o paciente já recebeu essa injeção, é necessário verificar o local de injeção que foi usado anteriormente e garantir que a dose anterior não resulte em reações adversas.
Os locais mais utilizados para injeções de IM incluem o músculo deltoide do ombro; a vasto lateralis da coxa; e os músculos ventrogluteal, glúteo medius, ou dorsogluteal do quadril. É melhor evitar administrar injeções de IM no músculo dorsogluteal, porque este local está associado a um risco aumentado de atingir um vaso sanguíneo, nervo ou osso.
Este vídeo se concentrará nos passos essenciais que toda enfermeira deve seguir para preparar e administrar corretamente uma injeção de IM.
This video demonstrates the preparation and administration of IM medications. According to best practices, IM medications should be administered in the deltoid muscle for immunizations or medications less than 1 mL but not exceeding 2 mL. Large volumes (i.e., more than 2 mL but less than 3 mL) should be administered in the ventrogludeal muscle; this site is used for antibiotics. Common errors in IM medication administration include administering large volumes to the deltoid muscle or using the gluteal muscle, causing the medication and needle to hit a nerve, bone, or adipose tissue. Another common error is using long needle lengths in patients with small amounts of muscle tissue, also increasing the chances of hitting bone tissue and causing osteomyelitis. As with any injection, failure to create a taut surface and hesitating with the injection may result in needle tip contamination, and recapping a used needle may lead to a needle-stick injury. Therefore, strict adherence to safe needle practices should always be enforced.
Intramuscular, or IM, injection is a safe and effective alternate route commonly used to deliver medications, which includes antibiotics, hormones, and vaccinations. An intramuscular injection deposit medications deep into the muscle tissue. Since muscle fibers are well perfused, this route of administration provides quick uptake of the medication and allows administration of relatively large volumes.
This video will focus on the essential steps that every nurse should follow in order to correctly prepare and administer an intramuscular injection
Before delving into the protocol, let’s review the common intramuscular injection sites and considerations associated with site and needle selection. The sites that are most commonly utilized for IM injections include the shoulder’s deltoid muscle; the thigh’s vastus lateralis; and the hip’s ventrogluteal, gluteus medius, or dorsogluteal muscles. The deltoid site is most commonly used for immunizations. However, only up to 1 mL of any medication may be administrated in this muscle. The gluteal site is commonly used to administer antibiotics, or any medication, when the volume exceeds 2 mL but is less than 3 mL for an adult.
Infants should receive all intramuscular medications in the vastus lateralis because it is the largest muscle at that developmental age. If administering an intramuscular injection into a child under age 2, the maximum amount that should be administered is 1 mL.
It is recommended to avoid administering intramuscular injections into the dorsogluteal muscle, because this location has an increased risk of hitting a blood vessel, nerve, or bone.
Needle selection is dependent upon the age of the patient, administration site, volume of fluid, amount of muscle and adipose tissue, and viscosity of the solution. Large bore needles-18 and 20 gauge-are appropriate for thick, viscous medications, while small bore needles-22 and 25 gauge-are appropriate for thinner medications and infants. Long needles-1 to 1½ inch-are most often used for patients with large amounts of adipose tissue covering the muscle site, or for deep muscles, such as the ventrogluteal muscle, whereas shorter needle lengths-5/8th to ½ inch-are appropriate for thin patients and pediatric patients to avoid needle sticks into the bone.
Let’s begin by reviewing the necessary preparation steps.
First, review the patient’s medical history. It is important to have a working knowledge of the patient’s preferences, allergies, and medication administration times. This information can be obtained by asking the patient and reviewing their Medication Administration Record, or MAR. It is also important to have an understanding of the medication being delivered to the patient. Medication information, like indication and adverse effects, can be obtained by referencing online databases. Next, keeping in mind the factors discussed in the previous section, select the most appropriate site for intramuscular injection.
Remember, adherence to the five “rights”-right patient, right medication, right dose, right route, right time-at three checkpoints of the safe medication administration process is imperative to prevent patient injury and harm. In order to learn about these five “rights” in detail, refer to another video in this collection.
Remember to wash or sanitize your hands before and after each patient encounter. Vigorous friction for at least 20 seconds should be applied while washing hands with soap and warm water or while applying hand sanitizer.
Once the injection site is selected, obtain the patient’s medication from the medication preparation area. Recall, adherence to the five “rights” at this first safety checkpoint of acquiring medication is critical. In the preparation area, first calculate the volume of medication needed for the correct patient dose. The calculated volume must be based on the concentration of the provided medication. For example, if the ordered dose is 2 milligrams and the vial concentration is 5 milligrams per milliliter, then the amount of volume to that you need to withdraw can be obtained by using the method of cross-multiplication, which is 0.4 milliliters in this case.
Then, remove the medication, which is a vial or an ampule, from the box and remove the vial top. Scrub the medication vial with an alcohol prep pad for 20 seconds, with friction and intent, while watching a wall clock or watch. Next, using aseptic technique, attach a blunt-tip needle to the syringe, remove the needle cap, and withdraw the appropriate amount of medication needed for injection. Note the viscosity of the medication being withdrawn from the vial. This will help determine the needle size needed for the patient’s IM injection. Hold the vial at eye-level and the needle tip below the level of medication to ensure the correct amount of liquid is withdrawn and air bubbles are avoided. If at any time during medication withdrawal, the needle hub, needle cap, or syringe connection point is contaminated from contact with hands or countertop, obtain new supplies and restart the medication preparation procedure. Next, slowly remove the needle from the medication. Then discard the blunt-tipped needle in an approved sharps container, while maintaining the sterility of the syringe containing the medication.
Now, attach the appropriate-sized needle to the syringe. Needle selection was discussed in the previous section of this video. Next, label the syringe with the medication name, dose, and any other information required by your institution’s labeling policy. Then, complete the second safety check, adhering to the 5 “rights” of medication administration. After the second safety check is complete, gather the necessary supplies, including alcohol prep wipes, non-sterile gloves, adhesive bandages or a cotton ball and silk/paper tape. Then, discard any remaining trash appropriately and proceed to the patient’s room.
Now, let’s learn how to perform IM injection. Upon entering the patient’s room, wash your hands thoroughly for 10-20 seconds, as described previously, and complete the third and final medication safety check, adhering to the 5 “rights” of medication administration. As with any medication administration, remind the patient of the medication purpose, any adverse reactions, and go over the administration procedure. Next, remove bed linens and the patient’s gown or clothing to access the selected injection muscle. Then locate the injection site.
If the deltoid has been selected as the injection muscle, locate the injection site by first locating the acromion process at the top of the shoulder. Then make a “V” with the index and middle fingers on the patient’s shoulder, with the tips of each finger touching the bottom of the acromion process. The deltoid injection site is in the middle of the “V.”
If the ventrogluteal muscle has been selected as the injection muscle, instruct your patient to lay on their side, exposing the selected hip. Locate the greater trochanter and the iliac crest. Place the palm of the hand on the patient’s hip, with the thumb on the patient’s greater trochanter. Point the index finger at the patient’s anterior iliac crest. Then spread the middle finger toward the back of the patient, forming a “V.” The needle injection site is located between the knuckles of the index and middle fingers.
Once the injection site has been located, don a pair of non-sterile gloves. If the patient has a latex allergy, be sure to use non-latex gloves to avoid allergic reactions. According to the CDC, it is unnecessary to clean the injection area with an alcohol prep pad, unless the skin is visibly soiled or dirty.
Next, obtain the prepared syringe. Hold the syringe between the thumb and index finger of your dominant hand and remove the needle cap with your non-dominant hand. Then, using your non-dominant hand, pull the patient’s skin taut between the thumb and forefinger, pushing the adipose tissue approximately 1 inch away from the muscle. In one quick motion, insert the needle at a 90° angle into the patient’s muscle. This is called the “z-track technique,” which prevents the medication from leaking into the subcutaneous tissue.
Slowly press the syringe plunger down with the thumb or index finger to inject the medication into the patient. The medication should be administered at a rate of 1 milliliter per 10 seconds. The syringe needle may be stabilized into the patient’s skin with the non-dominant hand. When the medication administration is complete, slowly remove the needle from the patient. Engage the needle safety device with the thumb and immediately discard the syringe and needle into the sharps container.
If blood is observed at the injection site, apply an adhesive bandage or cotton ball with silk/paper tape over the area. Then help the patient adjust their gown and bed linens. Next, remove the non-sterile gloves and immediately discard them, along with any other trash. Then thoroughly wash your hands for 10-20 seconds.
Finally, complete the required documentation in the patient’s electronic MAR. Be sure to document the medication administration time, date, location, and any other facility-required information. Before leaving the patient’s room, instruct the patient to immediately report any unusual reactions to the medication, such as injection site pain, redness, or swelling, to the nursing staff. Then exit the patient’s room and thoroughly wash your hands again.
“Selecting the injection site for the administration of IM medications is very important. Immunizations and medication doses between 1-2 milliliters should be administered in the deltoid muscle. Medication doses between 2-3 milliliters should be administered in the ventrogluteal muscle.”
“Common IM injection errors include administering large medication volumes into the deltoid muscle and selecting long needles in patients with small amounts of muscle tissue. These errors can lead to a needle hitting a nerve, adipose tissue, or bone, which may cause osteomyelitis”
“As with any injection, improper technique when recapping a needle may lead to a “needle stick” injury, and failure to create a taut surface or hesitating with the injection may result in needle-tip contamination. Therefore, all nurses must adherence to safe needle practices to safely and effectively administer IM injections.”
You’ve just watched a JoVE video on the preparation and administration of IM injections. You should have a better understanding of IM injection sites and factors involved in site and needle selection, and you should also be aware of the critical protocol steps for safe and effective delivery of IM medications. As always, thanks for watching!
