When monitoring an infant’s oxygen saturation, which location is least appropriate for sensor placement?

Placing the pulse oximeter sensor on the wrist of an infant is least appropriate because infants typically do not have enough tissue and bone structure in that area to ensure an accurate reading. The wrist is also more likely to involve movement and positioning changes, which can lead to inconsistent results for oxygen saturation levels.

In contrast, the heel is commonly used for infants as it provides a stable and easily accessible site for measurement that accommodates the smaller size of an infant’s limb. The great toe and index finger are also appropriate sites, as they tend to provide dependable readings without the complications of movement that might affect measurements at the wrist. Hence, the heel, great toe, and index finger are more suitable locations compared to the wrist for accurate oxygen saturation monitoring in an infant.