Abstract 3364: Transfusion of Stored Leucodepleted Red Blood Cells Interacts With Cardiopulmonary Bypass to Amplify Post Cardiac Surgery Acute Kidney and Lung Injury
Background Clinical studies have demonstrated associations between allogenic red blood cell (RBC) transfusion and organ dysfunction, particularly acute kidney injury (AKI) and transfusion associated lung injury (TRALI), however causality has not been established.
Aim To determine whether RBC transfusion has a causal effect on the development of AKI and TRALI in a large animal experimental model of post cardiopulmonary bypass (CPB) organ injury.
Method We evaluated serial functional and biochemical measures of renal and pulmonary injury in adult landrace pigs (50 –70kg, n=28) randomised to the following groups:
2.5 hours of CPB,
Sham procedure plus RBC transfusion
D, 2.5 hours of CPB plus RBC Transfusion.
All pigs were recovered for 24 hours prior to organ harvest and histological assessment.
Results CPB elicited AKI manifest by a reduction in creatinine clearance when compared to Sham Procedure at 24 hours. Transfused pigs received 1000mls (4 units) of cross-matched allogenic leucodepleted RBC stored in SAG-M preservative for 42 days. Accumulation of toxic metabolites within the supernatant as well as cellular changes showed considerable homology to those measured in human RBC units. RBC transfusion interacted with CPB resulting in more severe AKI compared to CPB alone (creatinine clearance and microalbuminuria). This was associated with significant renal tubular dilatation and vacuolation, a reduction in the medullary ATP/ADP ratio but with no effect on nitric oxide bioavailability. RBC transfusion also interacted with CPB to cause a significant reduction in lung compliance and an increase in the work of breathing. Transfusion of 14 day old RBC units resulted in similar lung injury but not AKI. Absolute mean differences are presented in the table⇓.
Conclusion RBC transfusion interacts with CPB to elicit severe AKI and TRALI. Modification of stored RBC units prior to transfusion may reduce the incidence of organ dysfunction post cardiac surgery.