Which site is appropriate for an intramuscular injection of vitamin K in a newborn?

Which site is appropriate for an intramuscular injection of vitamin K in a newborn?

• A. Vastus lateralis
• B. Dorsogluteal
• C. Deltoid
• D. Rectus femoris

Answer: (A)

For a newborn, the safest and most reliable intramuscular site is the vastus lateralis, the outer part of the thigh. This muscle has adequate mass in infants and sits away from major nerves and vessels, reducing the risk of nerve injury or vascular damage during injection. The dorsogluteal area is avoided because the sciatic nerve runs there, posing a real risk to the infant. The deltoid is too small in a newborn to safely receive an IM injection, and the rectus femoris is not preferred due to less predictable absorption and proximity to underlying structures. Therefore, vitamin K given to a newborn is best administered in the vastus lateralis.

For a newborn, the safest and most reliable intramuscular site is the vastus lateralis, the outer part of the thigh. This muscle has adequate mass in infants and sits away from major nerves and vessels, reducing the risk of nerve injury or vascular damage during injection. The dorsogluteal area is avoided because the sciatic nerve runs there, posing a real risk to the infant. The deltoid is too small in a newborn to safely receive an IM injection, and the rectus femoris is not preferred due to less predictable absorption and proximity to underlying structures. Therefore, vitamin K given to a newborn is best administered in the vastus lateralis.