Abstract 15580: Blood Transfusion in Ascending Aortic Surgery: No Inherent Cause for Concern

Introduction: There is widespread concern that blood transfusion has a strong adverse impact on early/late surgical survival, so hematocrit is often allowed to drift very low. We investigate whether this adverse impact of transfusion is seen in aortic surgery.

Methods: The records of 870 patients who underwent open ascending aortic or arch surgery from 2004 to 2016 by one surgeon at a large hospital were reviewed. Of these patients, 347 (39.9%) received a blood transfusion. The mean number of intra-op units transfused was 0.89, and the mean total units transfused (intra+post-op) was 2.45. High-volume transfusion (over 5 units) was needed for only 24 (6.9%) patients. We aimed to maintain a post-operative Hct of above 28%. Mean follow-up was 6.5 years.

Results: We found no significant difference in 30-day or 1-year mortality between the transfused and non-transfused groups, nor between high- and low-volume transfused patients. However, the long-term mortality beyond 1 year was higher in the transfused group than in the non-transfused group (13% vs 5.7%; p=0.0003). Notably, the transfused group was older than the non-transfused group (64.9 vs 57.7). On Kaplan-Meier analysis (Fig.1), there remained a significant adverse effect of transfusion overall (p=0.004), but this effect was eliminated if patients were propensity matched for age (p=0.18). There was no difference in high- vs low-volume K-M survival (p=0.58). Amongst those transfused, the total units transfused was not a predictor of mortality in any time-frame on multivariate regression when adjusting for pre-op Hct, blood transfusions, DHCA, type A dissection, and operation urgency (p=0.95, 0.56, and 0.45 for 30d, 1yr, and beyond 1yr respectively).

Conclusions: Transfusion and transfusion volume had no significant effect on early mortality, or even on late mortality after appropriate age adjustment. Should patient condition warrant, surgeons need not be concerned that transfusion will further reduce survival.