Acute pancreatitis results in a hypermetabolic, hyperdynamic, systemic inflammatory response syndrome that creates highly catabolic stress state.Gut rest, with or without parenteral nutrition, is considered to be the standard care in patients with acute pancreatitis aiming towards decrease enzyme production.Recent evidence however, suggests that enteral nutrition may be feasible and perhaps desirable in such patients.Studies have shown that the site in the gastrointestinal tract to which feedings are delivered determines whether the pancreas is stimulated and that jejunal feedings results in negligible increase in enzyme, bicarbonate, and volume output from the pancreas.Some experts suggest that enteral feedings stimulates lysosomal movement to cell surface, minimising intracellular release of pancreatic enzymes, and that it also reduces the production of proinflammatory mediators that may be therapeutic in patients with acute pancreatitis.
On the other hand, it is reported that Total parenteral nutrition, impairs humoral and cell mediated immunity, increases the vigour of the proinflammatory response, increases bacterial translocation, and increases infection rates in various critically ill patients. Lack of enteral feeding results in atrophy of the GI mucosa, bacterial overgrowth, increases intestinal permeability, and translocation of bacteria or bacterial products into the circulation.TPN , and thereby , enteral starvation results in rapid and severe atrophy of lymphoid tissue associated with gut , impairs B and T cell lymphocyte function and phagocytosis.
Most cases of acute pancreatitis are mild and self limiting, with serum enzyme levels returning to normal within 2-4 days.However early initiation of enteral feedings should be considered for moderate and severe pancreatitis.Placement of a jejunal feeding tube is best as it is seen that pancreatic stimulation from enteral nutrients decreases as the feeding site moves down the bowel. Well nourished patients with mild pancreatitis who can resume oral intake within few days may not need this but previously malnourished patients and patients unable to resume oral intake would benefit from enteral nutritional support.TPN should be only considered if enteral feeding is contraindicated for some reason.