Man and the animals are merely a passage and channel for food: Leonardo da Vinci, 1452-1519.

Nutritional therapy in the critically ill patient in the intensive care unit (ICU) is an important part of the total care of the patient. Nutrition can be given through parenteral nutrition or enteral nutrition therapy. Parenteral nutrition has been limited recently, but not exclusively, to patients who, for a variety of reasons, cannot be fed enterally. Although the debate concerning parenteral versus enteral nutrition continues, enteral nutrition is preferred whenever tolerated because of its potential less risk of infection, no need for central vein catheterization, improved gastrointestinal function, and decreased cost. Nevertheless, the use of this technique is limited by several technical problems and their related complications. It includes the lack of reliable access, high gastric residuals, gastroesophageal reflux, emesis, tracheal aspiration, diarrhea, and constipation. In this issue of Rev. Hosp. Clin. Fac. Med. S. Paulo, a multiprofessional group of health practitioners investigated whether there are advantages of continuous versus intermittent administration of gastric enteral nutrition in ICU patients. In a prospective randomized study, Serpa and colleagues enrolled 28 consecutive critically ill patients receiving mechanical ventilation and nasogastric feeding and divided them into two groups, those given continuous enteral nutrition or intermittent (8 aliquots at 3 hours intervals). Therapy was limited to 3 days of enteral nutrition, and residual gastric volume and compliance with the dietetic prescription were chosen as the end point. Enteral diet was marked with aniline-blue dye to recognize pulmonary aspiration and pneumonia was diagnosed when new lung X rays alterations were associated to clinical symptoms. Residual gastric volumes were high in both groups. Pulmonary aspiration was suspected in both groups but confirmed just in one (continuous feeding). Total daily enteral nutrition intake was smaller than originally programmed volume in both groups and the reasons for interrupting enteral nutrition were referred as high residual volume as well as medical procedures. Of note was that enteral nutrition complications were high gastric residual in almost half of the patients, diarrhea in 14.3% and feeding tube displacement in 25%. These complications might be the reason why almost 20% of the patients had registered deficits in the dietary intake superior than the 40% origiMAN AND THE ANIMALS ARE MERELY A PASSAGE AND CHANNEL FOR FOOD LEONARDO DA VINCI, 1452-1519