title: Relationship between sampling volume of primary serum tubes and spurious hemolysis.
abstract: BACKGROUND
  We planned a study to establish whether spurious hemolysis may be present in low volume tubes or partially filled tubes.
  
  
  METHODS
  Four serum tubes were collected in sequence from 20 healthy volunteers, i.e., 4.0 mL, 13 x 75 mm (discard tube), 6.0 mL, 13 x 100 mm half-filled, 4.0 mL, 13 x 75 mm full-draw and 6.0 mL, 13 x 100 mm full-draw. Serum was separated and immediately tested for hemolysis index (HI), potassium, aspartate aminotransferase (AST), and lactate dehydrogenase (LDH).
  
  
  RESULTS
  The HI always remained below the limit of detection of the method (< 0.5 g/L) in all tubes. No statistically significant differences were recorded in any parameter except potassium, which increased by 0.10 mmol/L in 4 mL full-draw tubes. No clinically significant variation was however recorded in any tube.
  
  
  CONCLUSIONS
  The results suggest that all types of tubes tested might be used interchangeably in term of risk of spurious hemolysis.
authors.affiliation: U .O. Diagnostica Ematochimica, Azienda Ospedaliero-Universitaria di Parma, Italy. glippi@ao.pr.it
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Lippi
authors.forename: Roberta
authors.initials: R
authors.lastname: Musa
authors.forename: Luisita
authors.initials: L
authors.lastname: Battistelli
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Cervellin
mesh_terms: D000328:Adult; D001219:Aspartate Aminotransferases / Q000097:blood; D004864:Equipment and Supplies; D005260:Female; D006461:Hemolysis; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D057230:Limit of Detection; D008297:Male; D008875:Middle Aged; D011188:Potassium / Q000097:blood; D012016:Reference Values; D044967:Serum; D013048:Specimen Handling
chemical_list: D007770:L-Lactate Dehydrogenase; D001219:Aspartate Aminotransferases; D011188:Potassium