Certified Medical Assistant (CMA AAMA)PharmacologyMedium
A medical assistant is preparing to administer an immunization to a 9-month-old infant. Which of the following intramuscular injection sites is most appropriate for this age group?
- ADorsogluteal
- BDeltoid
- CVentrogluteal
- DVastus Lateralis
Show answer & explanationAnswer & explanation
Correct answer: D. Vastus Lateralis
The vastus lateralis muscle in the thigh is the preferred and safest site for intramuscular injections in infants and young children (up to 2 years old) because it is well-developed and free from major nerves and blood vessels.
Why the other options are wrong
- A. The dorsogluteal site carries a significant risk of sciatic nerve damage and is generally not recommended for any age group, especially not infants.
- B. The deltoid muscle is not sufficiently developed in infants for IM injections and has a higher risk of nerve damage.
- C. The ventrogluteal site is an acceptable IM site for children over 12 months and adults, but vastus lateralis is preferred for infants.
Infant IM Injection Site
The vastus lateralis muscle is the preferred site for intramuscular injections in infants and toddlers (0-2 years).
- Large, well-developed muscle.
- Located in the anterolateral thigh.
- Low risk of nerve or blood vessel damage.
Memory trick: Infants need their 'V'accine in the 'V'astus.