The nurse observes the student nurse check the placement of a nasogastric (NG) tube prior to administering an intermittent feeding. Which student nurse actions require an intervention by the nurse? (select all that apply)
1. The student nurse checks the pH of the contents aspirated from the NG tube
2. The student nurse positions a stethoscope on the upper abdomen and listens as air is introduced into the NG tube
3. The student nurse uses a large-barreled syringe to aspirate for stomach contents
4. The student nurse flushes the NG tube with 30 mL of air before aspirating fluid
5. The student nurse places the end of the NG tube in a cup of water and watches for bubble formation.
