The shift from fluoride/oxalate to acid citrate/fluoride blood collection tubes for glucose testing - the impact upon patient results

Clin Biochem. 2014 May;47(7-8):683-5. doi: 10.1016/j.clinbiochem.2014.01.011. Epub 2014 Jan 23.

Abstract

Objectives: To ascertain whether or not the change in blood collection tubes for plasma glucose from fluoride/oxalate to citrate/fluoride/EDTA has had an effect upon the glucose results.

Methods: Plasma glucose results from fasting patients from 2007 to 2012 were extracted from the laboratory information system. The data was evaluated in order to see the potential impact on patient results due to the change in glucose stabilizer implemented in September 2010.

Results: The mean glucose result was increased by approximately 14% (difference: +0.80mmol/L) after the implementation of the citrate-buffered tubes (mean value=6.45mmol/L; n=15125) as compared to fluoride/oxalate tubes (mean value=5.65mmol/L; n=15867).

Conclusions: An increase in glucose results is seen after changing to citrate-buffered tubes due to the improved stabilizing effect as compared to fluoride. Properly collected blood samples will lead to the patient being correctly diagnosed. However, decision limits and reference intervals for glucose may need to be revised using citrate-tubes.

Keywords: Antiglycolytic additives; Diagnostic errors; Glucose; Preanalytical conditions.

MeSH terms

  • Blood Glucose / drug effects
  • Blood Specimen Collection / adverse effects
  • Blood Specimen Collection / methods*
  • Citrates / chemistry*
  • Female
  • Fluorides / chemistry*
  • Humans
  • Male
  • Oxalates / chemistry*
  • Phosphates / chemistry*

Substances

  • Blood Glucose
  • Citrates
  • Oxalates
  • Phosphates
  • fluorophosphate
  • Fluorides