Patient blood management (PBM) aims to improve patient outcome by managing and preserving a patient’s own blood and its components. Among the many recommended interventions, reducing intraoperative blood loss by using cell salvage (CS) devices is prioritized.^1,2 In cardiac surgery, CS describes the process involving the recovery of blood collected from the surgical field and residual blood collected from the extracorporeal circuit after weaning and decannulation, followed by autotransfusion to the patient. Recent international PBM guidelines support the routine use of CS devices for blood conservation during cardiac surgery either as a class IA recommendation (Society of Thoracic Surgeons/Society of Cardiovascular Anesthesiologists)³ or as a class IIA recommendation (European Association for Cardio-Thoracic Surgery/European Association of Cardiothoracic Anaesthesiology and Intensive Care).⁴ These recommendations are mainly based on the findings that the use of CS systems can reduce the requirements for transfusion of allogeneic blood products, especially red blood cells (RBCs), by about 20%. The latter has been reported in a recent Cochrane review including 5 large randomized controlled trials.⁵ Furthermore, the use of CS during cardiac surgery has been associated with a more favorable inflammatory response after cardiac surgery.⁶ However, most commercially available autotransfusion systems include a centrifugation and washing process, allowing only the salvage and re-transfusion of RBCs, whereas platelets and other coagulation factors are removed. Especially with large CS volume, the re-transfusion of only RBCs can be associated with coagulopathy due to dilution of coagulation factors and platelets.⁷ Recently, the Same (Smart Autotransfusion for Me) device (i-SEP, Nantes, France) has been introduced in clinical practice in different European countries. This device uses tangential filtration technology instead of centrifugation. Limited evidence from animal and clinical studies has suggested that this autotransfusion device is able to recover both RBCs and platelets and simultaneously allows for efficient washing of shed blood including removal of plasma proteins and heparin.^8,9

In the present issue of the Journal of Cardiothoracic and Vascular Anesthesia, Desfour et al.¹⁰ reported their evaluation of data from an observational, retrospective single-center study in 293 patients undergoing mostly elective cardiac surgery with cardiopulmonary bypass. Of the patients, 85 (29%) were treated with the Same device (CS-filtration group) whereas 208 were treated with a conventional CS device (CS-centrifugation group). The CS-centrifugation group showed an approximately 15% higher decrease in platelet count during the postoperative evaluation (mean difference, 9.94 × 10⁹/L; 95% confidence interval, 1.99-18.58; p = 0.02) than patients treated with the Same device. This finding remained consistent in the multivariable analysis. Furthermore, perioperative transfusion rates were significantly lower 28 days after surgery in the CS-filtration group (49% v 34%, p = 0.03). Finally, the authors reported lower rates of postoperative complications including infections, acute kidney injury, thromboembolic events, and intervention for bleeding with the Same device.

The present study is in good agreement with two other recent studies evaluating the Same device in cardiac surgery patients,^8,11 as well as an animal study using a porcine model of cardiopulmonary bypass.⁹ In the first in-human study, published in 2023, data from 50 patients undergoing various types of cardiac surgery using the Same device were presented.⁸ This study mainly focused on the performance of the CS device with respect to platelet recovery and safety issues. The authors reported similar efficacy for RBC recovery compared with conventional CS devices.⁸ Furthermore, removal ratios for heparin and free hemoglobin were nearly 99% and 95%, respectively. These removal ratios are comparable to those of conventional CS devices. Of interest, median platelet recovery was reported as >50%, with a post-treatment platelet concentration of nearly 120 × 10⁹/L in the recovered blood.⁸ More recently, Blum et al.¹¹ reported their findings on the Same device in this journal. In their study, shed blood from 44 patients undergoing on-pump heart valve surgery or coronary artery bypass grafting was processed with the Same device. Similar to the first study, Blum et al. reported a platelet count of 136 × 10⁹/L in the reinfusion bag. This platelet count corresponds to approximately 11.4% of one pooled platelet concentrate in Germany. Considering an average of 3 processing cycles per patient, the authors concluded that the use of the Same device would equate to roughly one-third of a standard platelet concentrate unit.¹¹ However, increased platelet count after cardiac surgery might be a questionable outcome as its impact on the need for platelet transfusion or patient outcomes remains largely unclear. A recent retrospective data analysis in >12,000 cardiac surgery patients found no association between postoperative platelet transfusion and increased morbidity and mortality.