Use of blood conservation devices has been studied previously. Three-way stopcock and syringes can those be used to preserve the discarded blood-infusate . Silver MJ et al  showed that the blood samples obtained with the blood-conserving arterial line were free of haemodilution or heparin contamination. In a small randomised control trial (RCT), Peruzzi WT et al  showed that the conservation group had better preservation of Hb with less volume of blood being discarded. However, the decrease in the transfusion requirements was not significant. Such devices were also found to be free of microbial contaminations .Despite their potential benefits, blood conservation devices are rarely used. In a survey of members of the Society of Critical Care Medicine, most agreed that such devices could be very useful in preventing anaemia .
Another survey found that such devices were used in only 18.4% of adult ICUs in England and Wales . One reason for such a paradox is the lack of convincing data on the effect of these devices on transfusion requirements. Encouragingly, findings of the present study strongly suggest that such devices do indeed reduce PRBC transfusion.Determination of a transfusion threshold or trigger in the ICU has been challenging. Due to the adoption of a restrictive transfusion practice  in our ICU, only 27.6% of our patient cohort received PRBC transfusions, which is lower than in previous studies [1,5]. This is reflected in the similar Hb levels at transfusion in both the control and active (7.1 �� 0.85 vs 7.25 �� 1.1 g/dL) groups.
It is likely that concurrent application of the restrictive transfusion practice where transfusion triggers are not individualised but guided, allowed demonstration of the effect of the blood conservation device on transfusion requirements. This notwithstanding, 23.8% and 29.7% patients in the control and active group respectively did receive transfusions above the suggested threshold (Table (Table2).2). In addition, a relatively smaller number of patients in the control group (control 17/80, 21.3% vs active 52/170, 30.6%) received a larger number of PRBC transfusions (control 62 units vs active 129 units of PRBC, table table2).2). This suggests that multiple transfusions of the same patients occurred in the control group.In our study, the control group had a greater loss of Hb; this finding is consistent with those of previous studies [15,18,19].
Patients in the control group had higher Hb levels on admission but similar Hb levels at discharge from ICU. There was also a numerical, though not statistically significant, trend toward better preservation of the Hb at discharge in the group without Carfilzomib transfusion (Table (Table22).Patients with the blood conservation device had a significantly lower ICU and hospital mortality.