[The choice of substrates in total parenteral nutrition]

This review contains a full outline on the choice of substrates in total parenteral nutrition (NPT). The basic properties of "conventional" substrates (glucose, long chain triglyceride-containing fat, common amino acid mixtures) are used to outline the general principles for NPT support in normal conditions and in stress (surgical and nonsurgical trauma, sepsis). Without taking into account factors which are not strictly metabolic (vascular access, local availability of products, costs), particular attention is then paid to "non-conventional" substrates and substrate mixtures, including some under study, with specific reference to properties and features which may motivate their choice.