Restrictive blood transfusion and 1-year mortality in patients undergoing open abdominal surgery: A retrospective propensity score-matched cohort study.

Background: The importance of patient blood management is increasingly recognized in surgery patients. This study aimed to examine the effect of perioperative restrictive blood transfusion on 1-year mortality and blood transfusion rate in open abdominal surgery.

Methods: We retrospectively studied 452 consecutive patients who underwent open abdominal surgery before (liberal group: 233 patients) and after (restrictive group: 219 patients) implementing intraoperative restrictive transfusion of red blood cell. The trigger levels of hemoglobin were less than 9-10 g/dL in the liberal group and less than 7-8 g/dL in the restrictive group. All-cause mortality at 1-year as the primary outcome and the transfusion rate of any allogeneic blood products as secondary outcome were compared between the liberal group and the restrictive group by the propensity-score matching.

Results: Among a total of 452 patients (69 ± 11 yr., 70.5 % men), overall mortality at 1 year was 8.4 % and the proportion of patients who received any allogeneic blood products was 19.6 %. Compared with 155 propensity-score matched patients of the liberal group, 155 matched patients of the restrictive group had significantly lower 1-year mortality (4 [2.5 %] versus 18 [11.6 %], p = 0.003, percent absolute risk reduction [%ARR]; 9.0, 95 % confidential interval [CI], 3.1-14.7) and had significantly lower proportion of patients who received any allogeneic blood products (21 [13.5 %] versus 41 [26.4 %], p = 0.006, %ARR; 12.9, 95 % CI, 3.9-21.5).

Conclusions: The results of this study indicate that intraoperative restrictive blood transfusion reduces 1-year mortality and the transfusion rate of allogeneic blood products.