To disinfect or not to disinfect that is the question – Procedure when drawing blood for alcohol measurements in Denmark

Swabbing with ethanol to disinfect the skin before venipuncture does not bias measurements of blood ethanol, as previously suspected. International evidence-based theory may not always be successfully integrated into local practices, where old customs may remain. So how are the local protocols for swabbing in practice – if they even do swab? Not disinfecting may risk patient safety. We aim to put a focus on the venipuncture disinfection procedure in practice when measuring blood alcohol for clinical matters and if their procedure refers to a guideline.

Specialized biomedical laboratory scientists (BLS) are typically responsible for the phlebotomy procedure in Denmark, thus questionnaires were sent to the relevant BLS in 2020 to map disinfection procedures in all Danish hospitals and affiliated blood draw clinics (n = 58).

The response rate was 93% (54/58). We observed an inter-laboratory dissimilarity in swabbing procedures, when measuring blood alcohol: A quarter did not use any disinfectant (26%), while the remaining disinfected with ethanol 55%, isopropanol 13%, and 6% with ethanol/chlorhexidine. Of the five Danish regions, three had a regional guideline (3/5), otherwise the swabbing protocol was locally based. There was a regional difference in disinfecting or not (Chi² p < 0,0001).

Danish protocols do not always parallel international literature and international guidelines. Not applying disinfectant may jeopardize patient safety. Laboratories are encouraged to work with evidence-based practice or follow newest standardized international guidelines.