1985 Volume 13 Issue 4 Pages 949-953
A simplified intravenous fat emulsion tolerance test (FETT) using 0.25ml/kg body weight of 10% Intralipid® has been established to evaluate triglyceride rich lipoprotein metabolism. Fractional removal rate (K2) of FETT and it's reliability were compared to that of intravenous fat emulsion tolerance test using 1ml/kg body weight of 10% Intralipid which is a modification of the method developed by Carlson. Both tests were done on the same 15 subjects within 7 days.
FETT: Fifteen subjects were fasted for 14 hours. Then 0.25ml/kg body weight of 10% Intralipid was injected intravenously in 90 seconds. Time measurements were started at midpoint of injection, and blood was sampled at 5, 7, 9, 11, 14, 17 and 20 minutes, respectively. Light scattering index (LSI) of serum diluted 1:100 in the physiological saline, was determined by nephelometer (Nephelotik DN 2110, Kyoto Dai-ichi Kagaku Co. Ltd.). The zero-time value was subtracted from the value for each post-injection sample. For calculation of fractional removal rate (K2) of fat emulsion, LSI's were plotted against time in a semilogarithmic plot. Slope of the regression line was determined by method of least squares and equation log Y=bx+a was calculated. The removal rate, K2, of fat emulsion was expressed as -b. Student's t-value was calculated as b/Sb ratio where Sb is standard error of b.
A modification of method by Carlson:The subjects were given 1ml/kg body weight of 10% Intralipid as intravenous infusion for 10 minutes. Time measurement was started at zero time of injection, and blood was sampled at 15, 20, 25, 30, 35, 40, and 50 minutes, respectively. K2' and Student's t-value were calculated in the same way as FETT was done. The mean value of K2 was approximately 2 times higher as compared with that of K2'. Also, K2 was higher than K2' in each subjects, respectively (Fig. 1). There was no significant difference between t-value of K2 and t-value of K2' (Fig. 2). K2 correlated" to K2' (r=0.78, p<0.001, Fig. 3). It was observed that fractional removal rate was significantly influenced by dose of administered fat emulsion. It may be concluded that FETT is a simple and good tool for study of triglyceride rich lipoprotein metabolism as a modification of method by Carlson.
