Nutrition in the critically ill.

When indicated, artificial feeding in critically ill patients should be instituted as early and as simply as possible. If feasible, enteral feeding is preferable but a period of intravenous nutrition is usually necessary in the critically ill. A compounded feed, administered via a sterile single lumen subclavian catheter is recommended. The volume and electrolyte composition are centrally important. High nitrogen and relatively low caloric intake are more likely requirements in stressed patients. The most important supplements are water soluble vitamins (including folate) and the trace element zinc. Safe practice requires a system of monitoring and awareness of potential complications.