RESUMEN
Ten patients aged between 18 and 73 years admitted to our intensive care unit were placed on exclusive artificial nutrition with Enteronutril receiving on average 2.855 +/- 496 kcal/day (715 +/- 125 g). This solution is poor in lipids (1.5%) and contains no linoleic acid (C18:2). Its effects on serum lipids were analysed after 5, 10 and 15 days of treatment. Total cholesterol (TC) and phospholipids (PL) showed no significant change. However, triglycerides (TG) rose on d15 and pre-beta-lipoproteins were significantly higher on d5. The latter rose further from d10 to d15. The C18:2 fraction of total lipids (TL) fell precipitously on d5 (-50%). Although C18:2 remained stable from d5 to d10, a new, slower decrease occurred from d10 to d15. This decrease was accompanied by a specific rise in oleic (C18:1) and palmitoleic (C16:1) acids. Palmitic (C16:0) and stearic (C18:0) acids were unaffected. Arachidonic acid (C20:4) remained within normal limits up to d15. Eicosatrienoic acid which was measurable on d0 presented no significant rise during the course of the study. The changes in C18:2 were inversely proportional to those of C18:1 or C16:1. This translated a lack of C18:2 relative to delta 9 desaturase (freed of the inhibition usually exerted by C18:2). These results showed that the body could maintain a sufficient level of linoleic acid to synthesize arachidonic acid by drawing on its C18:2 reserves from fatty tissue. Nevertheless, these reserves were progressively exhausted beyond d10, thereby causing a shortage of arachidonic acid.(ABSTRACT TRUNCATED AT 250 WORDS)