Pre-analytical delay of blood cultures: An observational study with an appraisal of the effects of laboratory centralisation

ABSTRACT Aims The United Kingdom Standards for Microbiology Investigations (UK SMI) recommends incubating inoculated blood cultures in an automated analyser as soon as possible and within 4 hours of collection. This observational study records compliance with a four hour standard by microbiology services across NHS England. The impact of laboratory centralisation on compliance rates was appraised. Methods Freedom of Information requests were submitted to 116 National Health Service Trusts/administrative units in England requesting retrospective audit data showing compliance with the standard over a single year. Additional information requested relating to service configuration and laboratory costs was supplemented by data available in the public domain. Results Responses were received from 89 Trusts (76.7%) comprising 149 acute hospitals. Compliance was poor with only four hospitals (2.7%) showing full compliance with the recommended standard. There was wide variation in compliance rates between hospitals across the region and hospitals within the same Trust and within Trust networks. Laboratory centralisation was not accompanied by a cohesive strategy which addressed the particular needs of a microbiology service. These changes hinder the optimal management of blood cultures. Conclusions Pre-analytical delay of blood cultures impedes timely reports which are critical to the effective management of sepsis while limiting the emergence of antimicrobial resistance. The need for a more comprehensive microbiology service in each acute care setting can be rationalised in view of the continued high prevalence of sepsis and the increasing emergence of antimicrobial resistance.