A cohort study assessing the impact of small volume blood tubes on diagnostic test quality and iatrogenic blood loss in a cohort of adult haematology patients

to estimate the reduction in blood volume loss and diagnostic test quality associated with introduction of small volume blood tubes in a cohort of haematology inpatients compared to a historical comparator group.prospective cohort study.haematology unit of a tertiary referral hospital in Adelaide.haematology inpatients.small volume blood tubes were used in an intervention cohort admitted between 2012-2013 and compared to a control cohort admitted between 2009-2010 where standard volume tubes had been used.the diagnostic test quality, specimen integrity and total reduction in blood loss associated with small volume tubes were estimated.small volume tubes demonstrated acceptable collinearity on commonly assay haematological and biochemical parameters. Small volume tubes were associated with a 42% reduction in blood volume loss equating to 8.5ml per patient per day or 180ml of blood over a three-week admission. Small volume tubes were associated with a slight but significantly increased rate of fibrin contamination of EDTA samples (0.2 to 0.5% of specimens).small volume tubes are associated with a substantial reduction in total blood volume collected per day in haematology inpatients. They have similar diagnostic validity and sample integrity to that of standard volume containers