What action does the nurse need to take first when suspecting that the patient receiving parenteral nutrition has an air embolus?

When a nurse suspects that a patient receiving parenteral nutrition has an air embolus, the priority intervention is to turn the patient to the left lateral decubitus position. This position helps trap any air that may have entered the bloodstream in the right atrium, preventing it from progressing into the pulmonary circulation where it would cause more severe complications.

In this scenario, positioning the patient in the left lateral position can help facilitate the closure of the foramen ovale, a fetal remnant that can allow air to pass into the bloodstream. This action is crucial because it may significantly reduce the risk of severe ramifications from the air embolus, such as a stroke or pulmonary embolism, allowing time for further interventions to be implemented.

Although notifying the healthcare provider and raising the head of the bed could be considered in some emergency situations, they are not the immediate actions that can help mitigate the risks posed by an air embolism. Performing the Valsalva maneuver can also be useful in some situations, but it is less effective in addressing an air embolus than the left lateral position, making it a secondary concern after ensuring the patient is appropriately positioned.