Nutrition in Acute Pancreatitis: A Review of Current Views

Nutritional support for the treatment of acute pancreatitis (AP) is an issue that is constantly being studied and developed. Nutritional support is important not only for maintaining mucosal permeability but also because AP is a metabolically demanding pathological process that activates an inflammatory cascade that leads to catabolic stress, the formation of reactive oxygen species, and the activation of immune responses that can quickly suppress innate immune regulation and antioxidant capacity. Traditionally, patients on the standard nutrition protocol start with a hypocaloric liquid diet, and if this first meal is well tolerated, a light diet is gradually introduced, followed by a fuller diet (solid foods with the calorie and fat content of a normal or low-fat diet) until the patient can take a full oral diet. Although this protocol is widely used, in practice, many randomised controlled trials have shown that immediate oral nutrition close to a normal diet is safe in presumed mild pancreatitis and may even lead to a shorter hospital stay. The first meal that patients with AP receive is crucial in determining whether oral nutrition is tolerated. In line with this goal, the timely administration of low-dose enteral nutrition (EN) is a widely supported approach. All international guidelines state that EN, which is preferable to full parenteral nutrition, should provide nutritional support in severe AP. Due to slow gastric emptying, patients may not be able to tolerate feeding through a nasogastric tube. Theoretically, feeding through a nasogastric tube can stimulate a more active secretion of pancreatic juice. However, while the placement of a nasogastric tube is a simple procedure, the nasojejunal tube must be placed radiologically or endoscopically, which can cause a delay in the onset of early EN. A systematic review and meta-analysis of the literature on EN formulas in AP showed that the use of polymeric formulas compared to semi-elemental formulas does not significantly increase the risk of nutritional intolerance, infectious complications, or death in patients with AP.