'True Blood' The Critical Care Story: An audit of blood sampling practice across three adult, paediatric and neonatal intensive care settings.

BACKGROUND Anaemia is common in critically ill patients, and has a significant negative impact on patients' recovery. Blood conservation strategies have been developed to reduce the incidence of iatrogenic anaemic caused by sampling for diagnostic testing. OBJECTIVES Describe practice and local guidelines in adult, paediatric and neonatal Australian intensive care units (ICUs) regarding blood sampling and conservation strategies. METHODS Cross-sectional descriptive study, conducted July 2013 over one week in single adult, paediatric and neonatal ICUs in Brisbane. Data were collected on diagnostic blood samples obtained during the study period, including demographic and acuity data of patients. Institutional blood conservation practice and guidelines were compared against seven evidence-based recommendations. RESULTS A total of 940 blood sampling episodes from 96 patients were examined across three sites. Arterial blood gas was the predominant reason for blood sampling in each unit, accounting for 82% of adult, 80% of paediatric and 47% of neonatal samples taken (p<0.001). Adult patients had significantly more median [IQR] samples per day in comparison to paediatrics and neonates (adults 5.0 [2.4]; paediatrics 2.3 [2.9]; neonatal 0.7 [2.7]), which significantly increased median [IQR] blood sampling costs per day (adults AUD$101.11 [54.71]; paediatrics AUD$41.55 [56.74]; neonatal AUD$8.13 [14.95]; p<0.001). The total volume of samples per day (median [IQR]) was also highest in adults (adults 22.3mL [16.8]; paediatrics 5.0mL [1.0]; neonates 0.16mL [0.4]). There was little information about blood conservation strategies in the local clinical practice guidelines, with the adult and neonatal sites including none of the seven recommendations. CONCLUSIONS There was significant variation in blood sampling practice and conservation strategies between critical care settings. This has implications not only for anaemia but also infection control and healthcare costs.