After abdominal surgery a client returns to the unit with a nasogastric (ng) tube to low intermittent wall suction. the primary healthcare provider prescribes an antiemetic every six hours as needed for nausea. when the client complains of nausea, what should the nurse do first? check for correct placement of the ng tube. administer the prescribed antiemetic. irrigate the ng tube with normal saline. notify the primary healthcare provider immediately.