title: Effects of free glycerol contained in intravenous fat emulsion on plasma triglyceride determination.
abstract: BACKGROUND
  Plasma triglyceride analyses to evaluate the clearance of IV fat emulsion are necessary in patients receiving parenteral nutrition. Enzymatic kits for triglyceride analysis measure the glycerol that is hydrolyzed from triglyceride. This study investigates the effect of fat emulsion free glycerol on plasma triglyceride determination.
  
  
  METHODS
  Venous blood from fasting volunteers (n = 10) was drawn into tubes containing EDTA and was centrifuged to separate the plasma. An IV fat emulsion containing 2.25% glycerol was added to plasma samples to create serial dilutions ranging from 0.049% to 0.245% final lipid concentration. Total triglyceride and free glycerol concentrations were determined in each dilution and control sample. The free glycerol concentration was subtracted from the total triglyceride concentration to yield a true triglyceride value.
  
  
  RESULTS
  Increasing concentrations of fat emulsion added to donor plasma produced increases in total triglyceride and free glycerol concentrations. The increase in free glycerol concentration produced significant concentration-related differences between total and true triglyceride concentrations.
  
  
  CONCLUSIONS
  The total triglyceride level overestimated the true triglyceride concentration due to fat emulsion free glycerol. To assure reliable triglyceride results in patients receiving fat emulsion, blanking for free glycerol should be considered.
authors.affiliation: Department of Surgery, Medical College of Georgia, Augusta, USA.
authors.forename: T R
authors.initials: TR
authors.lastname: Howdieshell
authors.forename: N
authors.initials: N
authors.lastname: Bhalla
authors.forename: J T
authors.initials: JT
authors.lastname: DiPiro
authors.forename: T
authors.initials: T
authors.lastname: Kuske
authors.forename: R
authors.initials: R
authors.lastname: Baisden
mesh_terms: D000328:Adult; D005217:Fat Emulsions, Intravenous / Q000493:pharmacokinetics; D005260:Female; D005990:Glycerol / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D006868:Hydrolysis; D008297:Male; D008875:Middle Aged; D010288:Parenteral Nutrition / Q000592:standards; D014280:Triglycerides / Q000097:blood* / Q000378:metabolism
chemical_list: D005217:Fat Emulsions, Intravenous; D014280:Triglycerides; D005990:Glycerol