Which is the appropriate technique for opening the airway of an infant with no suspected neck injury?

The appropriate technique for opening the airway of an infant with no suspected neck injury involves tilting the head back without hyperextending the neck. In infants, the airway is naturally positioned more anteriorly (forward), and their anatomy requires a more gentle approach to avoid obstruction and to ensure proper ventilation.

Tilting the head back allows for the alignment of the airway structures to facilitate airflow but does not involve hyperextension, which can actually lead to airway compression due to the flexibility of an infant's trachea. Maintaining a neutral position or a slight tilting aligns the airway effectively while also being mindful that infants have more short necks and larger heads relative to their bodies, making them more susceptible to airway obstruction if positioned incorrectly.

In contrast, lifting the chin and hyperextending the neck, or performing techniques suitable for older children or adults, does not account for the unique anatomical differences in infants. Gently lifting the chin while maintaining slight flexion is close but still would not be the most effective approach compared to the option of tilting the head back without hyperextension. Thus, the chosen method ensures both safety and effectiveness in managing an infant's airway.