Comparison of Perioperative Outcomes for Transfusion of Hemoconcentrated Bypass Versus Cell Saver Blood in Cardiac Surgical Patients.

Abstract

Objective: Hemoconcentration and cell saver use are blood conservation techniques that are often used in cardiac surgery to salvage the patient's own blood to reduce autologous transfusion. The purpose of this study was to examine the perioperative outcomes including transfusion rates in cardiac surgical patients receiving hemoconcentrated blood versus cell saver blood via retrospective chart review. We hypothesized that hemoconcentration would have better patient outcomes, including reduced transfusion rates, compared to only cell salvage technique.

Design: Single-center, retrospective chart review case-control study SETTING: Cardiac operating room of a tertiary care center PARTICIPANTS: Patients over 18 years old who underwent elective open-heart surgery with cardiopulmonary bypass between January 2015 to January 2018. Patients for emergencies, off-pump cases, transplants, and reoperations and with a need for second bypass were excluded.

Interventions: None.

Measurements and main results: The specific outcomes assessed include perioperative transfusion of packed red blood cells and blood products, intensive care unit (ICU) length of stay, hospital length of stay, and surgical site infections. Patient characteristics such as ejection fraction and comorbidities, pulmonary hypertension, atrial fibrillation history, and coagulation dysfunction were also analyzed. Propensity score matching was done to balance the covariates between the groups. The differences for each outcome outlined above were calculated. Of the 744 observations, 735 were used for analysis after propensity matching. Postoperative ICU red blood cell transfusions recorded a mean difference of -0.37 (95% CI: -0.78, 0.04). Postoperative ICU platelets and fresh frozen plasma recorded mean differences of -0.01 (95% CI: -0.11, 0.09) and -0.08 (95% CI: -0.19, 0.03), respectively. There were no significant differences in outcomes in bivariate- and covariate-adjusted models.

Conclusions: There is no significant difference in postoperative blood transfusion rates in hemoconcentrated versus cell saver blood usage in cardiac surgery patients. Further studies are needed to analyze specific quantities and ratios of hemoconcentrated and cell saver blood used in these patients for a more clinically relevant analysis. This would allow incorporation of hemoconcentration and cell saver techniques into better blood conservation processes and guide overall transfusion strategies to reduce transfusion rates of blood and blood products in cardiac surgical patients.