Final answer:
In acute pancreatitis, all oral fluids and food should be withheld initially. TPN or tube feeding with an elemental formula may be started if necessary.
Step-by-step explanation:
The nurse understands that initially, all oral fluids and food should be withheld for a patient with acute pancreatitis. This is because the inflamed pancreas needs rest and giving the digestive system a break can help reduce inflammation and allow the pancreas to heal.
In severe cases, total parenteral nutrition (TPN) may be started immediately. TPN provides all the necessary nutrients intravenously and bypasses the digestive system.
If the patient's condition allows, the nurse may also start tube feeding with an elemental formula to meet the patient's nutritional needs. An elemental formula consists of pre-digested nutrients that are easier for the digestive system to process.