title: Effect of order of draw of blood samples during phlebotomy on routine biochemistry results.
abstract: OBJECTIVE
  To investigate whether incorrect order of draw of blood samples during phlebotomy causes in vitro potassium ethylenediaminetetraacetic acid EDTA (kEDTA) contamination of blood samples.
  
  
  METHODS
  Serum kEDTA, potassium, calcium, magnesium, alkaline phosphatase, zinc and iron concentrations were measured in blood samples drawn before and after collecting blood into kEDTA containing sample tubes by an experienced phlebotomist using the Sarstedt Safety Monovette system.
  
  
  RESULTS
  EDTA was undetectable in all samples. The concentrations of other analytes were similar in blood samples drawn before and after collection of the EDTA blood sample.
  
  
  CONCLUSIONS
  Order of draw of blood samples using the Sarstedt Safety Monovette system has no effect on serum biochemistry results, when samples are taken by an experienced phlebotomist.
authors.affiliation: Department of Clinical Chemistry, New Cross Hospital, Wolverhampton, West Midlands, UK. raashda3@aol.com
authors.forename: Raashda A
authors.initials: RA
authors.lastname: Sulaiman
authors.forename: Michael P
authors.initials: MP
authors.lastname: Cornes
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Whitehead
authors.forename: Nadia
authors.initials: N
authors.lastname: Othonos
authors.forename: Clare
authors.initials: C
authors.lastname: Ford
authors.forename: Rousseau
authors.initials: R
authors.lastname: Gama
mesh_terms: D000293:Adolescent; D000328:Adult; D000469:Alkaline Phosphatase / Q000097:blood; D002118:Calcium / Q000097:blood; D004492:Edetic Acid / Q000097:blood*; D006801:Humans; D007501:Iron / Q000097:blood; D008274:Magnesium / Q000097:blood; D008875:Middle Aged; D018962:Phlebotomy / Q000379:methods* / Q000592:standards*; D011187:Posture; D011188:Potassium / Q000097:blood; D055815:Young Adult; D015032:Zinc / Q000097:blood
chemical_list: D004492:Edetic Acid; D007501:Iron; D000469:Alkaline Phosphatase; D008274:Magnesium; D015032:Zinc; D011188:Potassium; D002118:Calcium