title: Stability of Routine Biochemical Analytes in Whole Blood and Plasma From Lithium Heparin Gel Tubes During 6-hr Storage.
abstract: BACKGROUND
  The stability of biochemical analytes has already been investigated, but results strongly differ depending on parameters, methodologies, and sample storage times. We investigated the stability for many biochemical parameters after different storage times of both whole blood and plasma, in order to define acceptable pre- and postcentrifugation delays in hospital laboratories.
  
  
  METHODS
  Twenty-four analytes were measured (Modular® Roche analyzer) in plasma obtained from blood collected into lithium heparin gel tubes, after 2-6 hr of storage at room temperature either before (n = 28: stability in whole blood) or after (n = 21: stability in plasma) centrifugation. Variations in concentrations were expressed as mean bias from baseline, using the analytical change limit (ACL%) or the reference change value (RCV%) as acceptance limit.
  
  
  RESULTS
  In tubes stored before centrifugation, mean plasma concentrations significantly decreased after 3 hr for phosphorus (-6.1% [95% CI: -7.4 to -4.7%]; ACL 4.62%) and lactate dehydrogenase (LDH; -5.7% [95% CI: -7.4 to -4.1%]; ACL 5.17%), and slightly decreased after 6 hr for potassium (-2.9% [95% CI: -5.3 to -0.5%]; ACL 4.13%). In plasma stored after centrifugation, mean concentrations decreased after 6 hr for bicarbonates (-19.7% [95% CI: -22.9 to -16.5%]; ACL 15.4%), and moderately increased after 4 hr for LDH (+6.0% [95% CI: +4.3 to +7.6%]; ACL 5.17%). Based on RCV, all the analytes can be considered stable up to 6 hr, whether before or after centrifugation.
  
  
  CONCLUSIONS
  This study proposes acceptable delays for most biochemical tests on lithium heparin gel tubes arriving at the laboratory or needing to be reanalyzed.
authors.affiliation: Department of Metabolic Biochemistry, La Pitié Salpêtrière-Charles Foix University Hospital (AP-HP), Paris, France. dmonneret2@gmail.com.
authors.forename: Denis
authors.initials: D
authors.lastname: Monneret
authors.affiliation: Department of Metabolic Biochemistry, La Pitié Salpêtrière-Charles Foix University Hospital (AP-HP), Paris, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Godmer
authors.affiliation: Department of Metabolic Biochemistry, La Pitié Salpêtrière-Charles Foix University Hospital (AP-HP), Paris, France.
authors.forename: Ronan
authors.initials: R
authors.lastname: Le Guen
authors.affiliation: Department of Metabolic Biochemistry, La Pitié Salpêtrière-Charles Foix University Hospital (AP-HP), Paris, France.
authors.forename: Clotilde
authors.initials: C
authors.lastname: Bravetti
authors.affiliation: Department of Metabolic Biochemistry, La Pitié Salpêtrière-Charles Foix University Hospital (AP-HP), Paris, France.
authors.forename: Cecile
authors.initials: C
authors.lastname: Emeraud
authors.affiliation: Department of Metabolic Biochemistry, La Pitié Salpêtrière-Charles Foix University Hospital (AP-HP), Paris, France.
authors.forename: Anthony
authors.initials: A
authors.lastname: Marteau
authors.affiliation: Department of Metabolic Biochemistry, La Pitié Salpêtrière-Charles Foix University Hospital (AP-HP), Paris, France.
authors.forename: Rana
authors.initials: R
authors.lastname: Alkouri
authors.affiliation: Department of Metabolic Biochemistry, La Pitié Salpêtrière-Charles Foix University Hospital (AP-HP), Paris, France.
authors.forename: Fouzi
authors.initials: F
authors.lastname: Mestari
authors.affiliation: Department of Metabolic Biochemistry, La Pitié Salpêtrière-Charles Foix University Hospital (AP-HP), Paris, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Dever
authors.affiliation: Department of Metabolic Biochemistry, La Pitié Salpêtrière-Charles Foix University Hospital (AP-HP), Paris, France.
authors.forename: Françoise
authors.initials: F
authors.lastname: Imbert-Bismut
authors.affiliation: Department of Metabolic Biochemistry, La Pitié Salpêtrière-Charles Foix University Hospital (AP-HP), Paris, France.|Department of Biochemistry, Faculty of Pharmacy, Paris Descartes University, Paris, France.|UPMC University Paris 6, Paris, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Bonnefont-Rousselot
mesh_terms: D001800:Blood Specimen Collection / Q000295:instrumentation* / Q000379:methods*; D002474:Cell-Free System; D002498:Centrifugation; D006493:Heparin / Q000737:chemistry*; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D010949:Plasma / Q000737:chemistry*; D012016:Reference Values; D013997:Time Factors; D014280:Triglycerides / Q000097:blood; D005723:gamma-Glutamyltransferase / Q000097:blood
chemical_list: D014280:Triglycerides; D006493:Heparin; D007770:L-Lactate Dehydrogenase; D005723:gamma-Glutamyltransferase
keywords: biochemical analytes; plasma; preanalytical; stability; storage time; whole blood