When obtaining a rectal temperature from an infant, how far should the probe be inserted?

When obtaining a rectal temperature from an infant, it is recommended to insert the thermometer about 1/2 inch into the rectum. This depth is sufficient to ensure an accurate reading while minimizing discomfort and reducing the risk of injury to the delicate rectal tissue of the infant. Inserting the thermometer to this specified depth strikes a balance between achieving an accurate core temperature measurement and ensuring the safety and comfort of the patient.

Deeper insertion, such as 1 inch or more, can pose a risk of perforation or injury, which is particularly concerning in infants due to their smaller anatomy. Similarly, inserting the thermometer only a quarter inch may not be deep enough to obtain an accurate core temperature reading, leading to unreliable results. Thus, the guideline of 1/2 inch is established based on safety and effectiveness for this vulnerable population.