title: Low vacuum and discard tubes reduce hemolysis in samples drawn from intravenous catheters.
abstract: OBJECTIVE
  In-vitro hemolysis is a great challenge to emergency departments where blood is drawn from intravenous catheters (IVCs). Although high quality samples can be obtained by straight needle venipuncture, IVCs are preferred for various reasons. The aim of this study was to identify blood collection practices that reduce hemolysis while using IVC.
  
  
  METHODS
  The study was conducted at an emergency department where blood is drawn in ≥ 90% of patients from IVC. Hemolysis, measured spectrophotometrically, was compared between syringe and vacuum tubes. The following practices were tested in combination with vacuum collection; a Luer-slip adapter, a Luer-lock adapter, discard tubes and low vacuum tubes. Each intervention lasted 1 week and retrieved 154 to 297 samples. As reference, hemolysis was also measured in vacuum tubes retrieved from departments where only straight needle venipuncture is performed.
  
  
  RESULTS
  Vacuum collection led to more hemolytic samples compared with syringe tubes (24% versus 16% respectively, p=0.008). No difference in hemolysis was observed between the Luer-slip and the Luer-lock adapter. The use of discard (17% hemolytic, p=0.045) and low vacuum tubes (12% hemolytic, p<0.001) substantially decreased hemolysis. None of the interventions reduced the hemolysis rate to the level observed when drawing blood by straight needle venipuncture (3%, p<0.02).
  
  
  CONCLUSIONS
  In summary, both discard and low vacuum tubes reduce hemolysis while drawing blood from IVC. Of these practices the use of a low vacuum tube is preferred considering the less volume of blood and the amount of tubes drawn.
authors.affiliation: Laboratory of Clinical Chemistry and Hematology, VieCuri Medical Centre, Venlo, The Netherlands.
authors.forename: Connie
authors.initials: C
authors.lastname: Heiligers-Duckers
authors.affiliation: Emergency Department, VieCuri Medical Centre, Venlo, The Netherlands.
authors.forename: Nathalie A L R
authors.initials: NALR
authors.lastname: Peters
authors.affiliation: Emergency Department, VieCuri Medical Centre, Venlo, The Netherlands.
authors.forename: Jose J P
authors.initials: JJP
authors.lastname: van Dijck
authors.affiliation: Emergency Department, VieCuri Medical Centre, Venlo, The Netherlands.
authors.forename: Jan M J
authors.initials: JMJ
authors.lastname: Hoeijmakers
authors.affiliation: Laboratory of Clinical Chemistry and Hematology, VieCuri Medical Centre, Venlo, The Netherlands. Electronic address: marceljanssen@viecuri.nl.
authors.forename: Marcel J W
authors.initials: MJW
authors.lastname: Janssen
mesh_terms: D001800:Blood Specimen Collection / Q000295:instrumentation*; D002404:Catheterization / Q000295:instrumentation*; D006461:Hemolysis / Q000502:physiology*; D006801:Humans; D014618:Vacuum
keywords: Blood collection; Discard tube; Hemolysis; IVC; Intravenous catheter; Low vacuum tube; intravenous catheter