When administering ear drops to a 2-year-old, the nurse:

Choice A rationale

The abdomen, specifically 2 inches from the umbilicus, is a common site for subcutaneous injections due to the presence of ample adipose tissue, which allows for slower absorption of medications like insulin or heparin. Intradermal injections require a site with a thin epidermis and minimal subcutaneous tissue to ensure the medication remains within the dermal layer, making the abdomen unsuitable.

Choice B rationale

The anterior thigh is a common site for intramuscular injections, particularly in infants, due to the large muscle mass (vastus lateralis). While it can be used for subcutaneous injections, its muscularity and varying skin thickness make it less ideal for the precise shallow angle required for an intradermal injection, where the goal is to deposit the medication into the dermis.

Choice C rationale

The posterior upper arm, specifically the triceps area, is frequently utilized for subcutaneous injections, such as insulin or certain vaccines, because it offers sufficient subcutaneous tissue. However, similar to the anterior thigh, its anatomical characteristics with thicker skin and subcutaneous fat layers make it less optimal for the very superficial intradermal injection technique.

Choice D rationale

The upper chest, particularly below the clavicle and above the breasts, is an appropriate site for intradermal injections. This area, along with the inner forearm and upper back, has a thin epidermis and less subcutaneous tissue, which facilitates the proper placement of the medication within the dermis, allowing for the formation of a visible wheal, a key indicator of a successful intradermal injection.

Choice A rationale

Absence of pain at the site of an intradermal injection does not confirm proper administration. While minimizing pain is a goal, the primary indicator of correct intradermal placement is the formation of a bleb, which signifies the medication has been correctly deposited within the dermal layer, not subcutaneously.

Choice B rationale

Immediate blood return at the site of an intradermal injection indicates improper technique, specifically penetration into a blood vessel. Intradermal injections are administered into the avascular dermal layer; therefore, aspiration should yield no blood, and blood return necessitates withdrawing and restarting the injection at a new site.

Choice C rationale

Skin remaining flat and turning red at the injection site is not indicative of proper intradermal injection. Redness may occur due to irritation, but a flat appearance suggests the medication was either injected too deeply into the subcutaneous tissue or insufficient volume was administered into the dermal layer to form a bleb.

Choice D rationale

The immediate formation of a bleb or wheal, resembling a small blister, is the definitive sign of a correctly administered intradermal injection. This occurs because the medication is deposited precisely into the superficial dermal layer of the skin, causing a localized elevation as the fluid displaces tissue.