Aims:To test the hypothesis that compliance with a hospital protocol on peripheral blood culture (PBC) collection in adults is associated with a reduction in PBC contamination, and to investigate likely contributing factors for contamination.Methods:A prospective cohort study was conducted, utilising data collection by participant questionnaire completion, and utilising bacteriology laboratory results on PBCs. Participants were all healthcare workers involved in obtaining PBCs from adults.Results:1460 PBCs with questionnaires were received. Contamination among the 1460 PBCs as a whole was 8.8%. 766 of the questionnaires were sufficiently complete to allow analysis of blood culture contamination in relation to protocol compliance. Among these, protocol compliance was 30% and contamination was 8.0%. When the protocol was complied with, 2.6% of PBCs were contaminated, but when the protocol was not followed, contamination was significantly higher at 10.3% (OR 4.35, 95% CI 1.84 to 12.54). Univariate analysis on all 1460 PBCs suggested that the site for blood collection, and disinfection of the venepuncture site were important factors in PBC contamination: when no venepuncture site disinfection was performed, contamination was significantly higher than when alcohol was used (5.1% versus 15.8%, OR 3.46, 95% CI 2.01 to 5.97); when a PBC collection site other than a fresh peripheral vein was used, contamination was significantly higher (7.3% versus 12.0%, OR 1.75, 95% CI 1.03 to 2.96).Conclusions:Compliance with a hospital protocol on PBC collection technique in adults significantly reduces blood culture contamination.
