Put simply pancreatitis is inflammation of the pancreas. Your pancreas produces enzymes that aid in digestion and hormones that help to regulate how your body will process sugar. Out of pancreatitis, appendicitis, cholecystitis, and gastric ulcer, the condition that is most likely to have a nursing diagnosis of fluid volume deficit is in fact pancreatitis.
Hypovolemic shock caused by fluid shifts is a major factor in acute pancreatitis. Though the other conditions might present some sort of similar symptoms pancreatitis is the most likely.