A nurse is caring for an infant who has a prescription for continuous pulse oximetry. Which of the following actions should the nurse take?

A. Warm the infant's extremity for 1 min prior to placing the sensor probe: While cold extremities can affect pulse oximetry readings, brief warming alone may not reliably improve accuracy. Proper probe placement and minimizing movement are more critical to obtaining consistent readings. B. Keep the infant's foot immobilized while the sensor is in place: Immobilizing the extremity prevents motion artifact, which can interfere with pulse oximetry accuracy. This is a recommended action for continuous monitoring in infants, as movement can cause false low or fluctuating readings. C. Place a sensor on the infant's index finger: In infants, the fingers are often too small for standard pulse oximetry probes. Preferred sites include the foot or wrist, which accommodate the sensor without compromising accuracy. D. Place a sock over the infant's foot to secure the sensor: Covering the sensor with a sock may create pressure or interfere with proper probe function, and it can trap moisture, which affects readings. Securing the probe with gentle adhesive or specialized wraps is safer.