A guide to enteral access procedures and enteral nutrition.

The advent of total parenteral nutrition in the late 1960s meant that no situation remained in which a patient could not be fed. Unfortunately, total parenteral nutrition was complicated by serious infective and metabolic side effects that undermined the beneficial effects of nutrient repletion. Consequently, creative ways of restoring upper gut function were designed, based on semielemental diets and novel feeding tube systems. The employment of specific protocols and acceptance of increased gastric residual volumes has allowed most patients in intensive care to be fed safely and early by nasogastric tube. However, nasogastric feeding is unsuitable for patients with severely compromised gastric emptying owing to partial obstruction or ileus. Such patients require postpyloric tube placement with simultaneous gastric decompression via double-lumen nasogastric decompression and jejunal feeding tubes. These tubes can be placed endoscopically 40-60 cm past the ligament of Treitz to enable feeding without pancreatic stimulation. In patients whose disorders last more than 4 weeks, tubes should be repositioned percutaneously, by endoscopic, open or laparoscopic surgery. Together, the advances in enteral access have improved patients' outcomes and led to a 70-90% reduction in the demand for total parenteral nutrition.