The influence of ultrafiltration on red blood cell transfusion during cardiopulmonary bypass

Abstract

Background: Ultrafiltration during cardiopulmonary bypass (CPB) reduces fluid overload and inflammatory mediators in open-heart surgery and is thought to reduce the risk of red blood cell (RBC) transfusion. We evaluated its effectiveness in reducing RBC transfusions in a large population undergoing cardiac surgery, among patients in general as well as by gender. Methods: We analyzed 40,650 propensity-matched adult cardiac surgery cases conducted over a 61-month period at 195 hospitals. We assessed the risk of intraoperative transfusion (⩾1 unit RBC) according to body surface area (BSA)-normalized ultrafiltration volume via mixed-effects binary logistic regression. Our statistical model controlled for 12 demographic and operative variables as well as for center level tendencies in ultrafiltration use and intraoperative RBC transfusion. In light of recent findings on gender and risk of transfusion, we also included an interaction effect between gender and ultrafiltration volume (UV). Results: Ultrafiltration was associated with an increased crude rate of RBC transfusion (32.1% vs. 28.1%, p<0.001), but equivalent crude median hematocrit change from first in operating room to nadir on bypass (−11% in both groups, p = 0.133). After controlling for patient, operative and site-level characteristics, we found no statistically significant effect on transfusion rate by volume of ultrafiltrate removed nor did we find statistical support for any gender-specific effect of ultrafiltration. Conclusions: Ultrafiltration is not associated with a reduction of risk of RBC transfusion during cardiac surgery. The use of ultrafiltration as a method for reducing intraoperative RBC transfusion warrants further study.

Hematologic evaluation of intraoperative autologous blood collection and allogeneic transfusion in cardiac surgery

“…5 As hemodilution typically occurs with the initiation of CPB, our multifaceted efforts toward minimizing hemodilution included fluid restriction before CPB, retrograde autologous priming, and hemofiltration during CPB. 11,12 Intraoperative fluid administration was guided by transesophageal echocardiography for maintenance of hemodynamic parameters. The decision to perform AWB collection was at the discretion of the staff anesthesiologist, and thus it was not a randomized intervention.…”

Retrospective evaluation of ultrafiltration during cardiac surgery with cardiopulmonary bypass in adult patients with increased neutrophil to lymphocyte ratio

“…Neutrophils, which are central in the mediation of systemic inflammatory responses to CPB and are activated by the complement system and kallikrein, arrive rapidly at sites of acute inflammation where they are responsible for phagocytosis and killing of invading pathogens by releasing proteolytic and cytotoxic enzymes (including elastase, myeloperoxidase and lactoferrin), chemokines, cytokines and arachidonate metabolites [7]. Over-activation of neutrophils, on one hand, is involved in the collateral destruction of tissues and cell together with injury from oxygen free radicals.…”

“…Systemic inflammation during CPB is triggered by neutrophil activation, which can be monitored by a novel biomarker, the neutrophil to lymphocyte ratio (NLR) [7]. A high NLR has been associated with poor prognosis in many cardiovascular diseases [8].…”

The effect of various blood management strategies on intraoperative red blood cell transfusion in first-time coronary artery bypass graft patients

“…23 More recently, however, we have questioned the use of ULF as a means of reducing RBC transfusion even after 1,300 mL of plasma water removed. 24 Most of the studies that have demonstrated an effect of ULF on RBC transfusion have combined ULF with other blood management techniques.…”