Transfusion tomorrow: Royal College of Pathologists, November 2010

Massive blood transfusion after the first cut in liver transplantation predicts renal outcome and survival

INTRODUCTION

Transfusion requirements of blood products may provide useful prognostic factors for the prediction of short-term patient mortality and renal outcome after liver transplantation.

PATIENTS AND METHODS

Two hundred ninety-one consecutive liver transplants in adults were analysed retrospectively. Combined and living-related liver transplants were excluded. The amount of transfused packed red blood cells (PRBC) and units of platelets (UP) within the first 48 h were investigated as prognostic factors to predict short-term patient mortality and renal outcome. Receiver operating characteristic (ROC) curve analysis with area under the curve (AUC), Hosmer-Lemeshow tests and Brier scores were used to calculate overall model correctness, model calibration and accuracy of prognostic factors. Cut-off values were determined with the best Youden index.

RESULTS

The potential clinical usefulness of PRBC as a prognostic factor to predict 30-day mortality (cut-off 17.5 units) and post-transplant haemodialysis (cut-off 12.5 units) could be demonstrated with AUCs >0.7 (0.712 and 0.794, respectively). Hosmer-Lemeshow test results and Brier scores indicated good overall model correctness, model calibration and accuracy. The UP proved as an equally clinically useful prognostic factor to predict end-stage renal disease (cut-off 3.5 units; AUC = 0.763). The association of cut-off levels of PRBC with patient survival (p < 0.001, log-rank test) and dialysis-free survival (p < 0.001, log-rank test) was significant (cut-off levels 17.5 and 12.5 units, respectively) as well as the association of UP with dialysis-free survival (p < 0.001, log-rank test) (cut-off level 3.5 units).

CONCLUSIONS

The impressive discriminative power of these simple prognostic factors for the prediction of outcome after liver transplantation emphasizes the relevance of strategies to avoid excessive transfusion requirements.

Blood transfusion and the risk of acute kidney injury after transcatheter aortic valve implantation

BACKGROUND

Blood transfusion is associated with acute kidney injury (AKI) after transcatheter aortic valve implantation (TAVI). We sought to elucidate in more detail the relation between blood transfusion and AKI and its effects on short- and long-term mortality.

METHODS AND RESULTS

Nine hundred ninety-five patients with aortic stenosis underwent TAVI with the Medtronic CoreValve or the Edwards Valve in 7 centers. AKI was defined by the Valve Academic Research Consortium (absolute increase in serum creatinine ≥0.3 mg/dL [≥26.4 μmol/L] or ≥50% increase ≤72 hours). Logistic and Cox regression was used for predictor and survival analysis. AKI occurred in 20.7% (n=206). The number of units of blood transfusion ≤24 hours was the strongest predictor of AKI (≥5 units, OR, 4.81 [1.45-15.95], 3-4 units, OR, 3.05 [1.24-7.53], 1-2 units, OR, 1.47 [0.98-2.22]) followed by peripheral vascular disease (OR, 1.48 [1.05-2.10]), history of heart failure (OR, 1.43 [1.01-2.03]), leucocyte count ≤72 hours after TAVI (OR, 1.05 [1.02-1.09]) and European System for Cardiac Operative Risk Evaluation (EuroSCORE; OR, 1.02 [1.00-1.03]). Potential triggers of blood transfusion such as baseline anemia, bleeding-vascular complications, and perioperative blood loss were not identified as predictors. AKI and life-threatening bleeding were independent predictors of 30-day mortality (OR, 3.15 [1.56-6.38], OR, 6.65 [2.28-19.44], respectively), whereas transfusion (≥3 units), baseline anemia, and AKI predicted mortality beyond 30 days.

CONCLUSIONS

AKI occurred in 21% of the patients after TAVI. The number of blood transfusions but not the indication of transfusion predicted AKI. AKI was a predictor of both short- and long-term mortality, whereas blood transfusion predicted long-term mortality. These findings indicate that outcome of TAVI may be improved by more restrictive use of blood transfusions.