EFLM Position Paper Reaffirms Importance of Blood Draw Order to Prevent Sample Contamination
The EFLM Working Group for the Preanalytical Phase reviewed the evidence on order of draw during venous blood collection and concluded that significant sample contamination occurs when recommended sequences are not followed. Given that ideal phlebotomy conditions are not always achievable, the group reaffirms the standard order: blood culture tubes first, then plain/gel tubes, then additive tubes, as a patient safety measure.
The original study
Order of blood draw: Opinion Paper by the European Federation for Clinical Chemistry and Laboratory Medicine (EFLM) Working Group for the Preanalytical Phase (WG-PRE).
- Authors
- Cornes M, van Dongen-Lases E, Grankvist K, Ibarz M, Kristensen G, Lippi G, et al.
- Journal
- Clinical chemistry and laboratory medicine
- Type
- Journal Article, Practice Guideline
- PMID
- 27444170
Original abstract
It has been well reported over recent years that most errors within the total testing process occur in the pre-analytical phase (46%-68.2%), an area that is usually outside of the direct control of the laboratory and which includes sample collection (phlebotomy). National and international (WHO, CLSI) guidelines recommend that the order of draw of blood during phlebotomy should be blood culture/sterile tubes, then plain tubes/gel tubes, then tubes containing additives. This prevents contamination of sample tubes with additives from previous tubes that could cause erroneous results. There have been a number of studies recently looking at whether order of draw remains a problem with modern phlebotomy techniques and materials, or it is an outdated practice followed simply because of historical reasons. In the following article, the European Federation of Clinical Chemistry and Laboratory Medicine Working Group for the Preanalytical Phase (EFLM WG-PRE) provides an overview and summary of the literature with regards to order of draw in venous blood collection. Given the evidence presented in this article, the EFLM WG-PRE herein concludes that a significant frequency of sample contamination does occur if order of draw is not followed during blood collection and when performing venipuncture under less than ideal circumstances, thus putting patient safety at risk. Moreover, given that order of draw is not difficult to follow and knowing that ideal phlebotomy conditions and protocols are not always followed or possible, EFLM WG-PRE supports the continued recommendation of ensuring a correct order of draw for venous blood collection.