Plasma clearance of intravenous fat emulsion in acute bacterial infections

A variety of abnormalities in lipid metabolism during infection have been reported and it has been questioned whether intravenous fat emulsion should be given in septic states. This study was designed to investigate the removal of a fat emulsion from plasma during septicaemia. An intravenous fat tolerance test (0.1 g of fat in the form of Intralipid 10% per kg b.w.) was performed in 28 adult patients who had been admitted for suspected septicaemia. All patients were febrile (mean body temperature 38.9 +/- 0.1 degrees C SEM), the majority had leucocytosis (mean value 10.5 +/- 1.0 10 (9)1 ) and all were haemodynamically stable. On the basis of bacterial cultures taken from various locations, the patients were classified as septic (n = 12; gram-negative sepsis, n = 8; gram-positive sepsis, n = 4), infected but without septicaemia (n = 9) or febrile of unknown cause (all cultures negative, n = 7). Plasma fractional removal rates of intravenous fat were similar in the different groups. The mean plasma clearance rate of intravenous fat was 6.6 +/- 0.5 (% minute), which does not differ from that reported for healthy controls. All patients with proven septicaemia and 5 non-septic patients were studied two weeks later when their infection had been treated and they were off antibiotic medication. The plasma clearance rate of i.v. fat was significantly lower in the recovery phase than during the acute febrile state (5.9 +/- 0.5 vs 4.2 +/- 0.4 %/min, n = 17; p < 0.05). It is concluded that clearance of intravenous fat emulsions from plasma is unimpaired in haemodynamically stable patients with septicaemia or other acute infections.