Management of blood transfusion in aortic valve surgery: impact of a blood conservation strategy

Abstract

Background: There are limited data in the literature concerning the effect of a blood conservation strategy (BCS) on aortic valve replacement (AVR) patients.

Methods: From 2007 to 2011, 778 patients underwent AVR at a single institution. During this period, a multidisciplinary BCS was initiated with emphasis on limiting intraoperative hemodilution, tolerance of perioperative anemia, and blood management education for the cardiac surgery care providers.

Results: Mortality was 3.0% (23 of 778) overall and 1.7% (9 of 522) for isolated first-time AVR. There was no difference in rates of mortality (p = 0.5) or major complications (p = 0.4) between the pre-BCS and post-BCS groups; however, the BCS was associated with a lower risk of major complications (odds ratio, 1.7; p = 0.046) by multivariable analysis. The incidence of red blood cell (RBC) transfusion decreased from 82.9% (324 of 391) to 68.0% (263 of 387; p < 0.01). Of those patients who did not receive any day-of-operation RBC transfusions, 64.5% (191 of 296) did not receive any postoperative RBC transfusions. Lower risk of RBC transfusion was associated with isolated AVR (p < 0.01), a minimally invasive approach (p < 0.01), and BCS (p < 0.01), whereas a greater risk of RBC transfusion was associated with older age (p < 0.01), prior cardiac operation (p = 0.01), female sex (p < 0.01), and smaller body surface area (p < 0.01). Day-of-operation RBC transfusion of 2 units or more was associated with increased deaths (p = 0.01), prolonged intubation (p < 0.01), postoperative renal failure (p = 0.01), and increased incidence of any complication (p < 0.01).

Conclusions: Perioperative BCS reduced RBC transfusion in AVR patients without an increase in mortality or morbidity. Guidelines for BCS in routine cardiac operations should be extended to AVR patients.

Keywords: 16; AVR; BCS; BSA; CABG; COPD; CPB; FFP; OR; RBC; SCA; SD; STS; Society of Cardiovascular Anesthesiologists; The Society of Thoracic Surgeons; aortic valve replacement; blood conservation strategy; body surface area; cardiopulmonary bypass; chronic obstructive pulmonary disease; coronary artery bypass graft; fresh frozen plasma; odds ratio; red blood cell; standard deviation.