Intra‐operative cell salvage in cardiac surgery may increase platelet transfusion requirements: a cohort study

Comparative evaluation of two autotransfusion devices in a 72h survival swine model of surgically induced controlled splenic bleeding

Autotransfusion is a key strategy in hemorrhagic surgical procedures, reducing risks like disease transmission and immunosuppression due to allogenic transfusion. While conventional devices efficiently process red blood cells by centrifugation, they don't address complications requiring additional platelet transfusions. The innovative same™ device (i-SEP, France), utilizing hollow-fiber filtration, preserves both red blood cells and platelets without damaging cell integrity. This study designed as a prospective randomized controlled trial compared cell concentration and washout performances of two autotransfusion devices, a preclinical version of same™, the conventional centrifugation-based Xtra® (LivaNova, UK); and effects of retransfusion versus no transfusion in 21 Yucatan minipigs submitted to a surgically induced controlled splenic bleeding. Animals were divided into three groups (no-transfusion control group, same group and xtra group) and monitored postoperatively for 72 hours during which serial animal blood samples were collected for hematologic, biochemical and coagulation analyses and tests. Both autotransfusion devices showed high performances in red blood cell yields and concentrations, with a significant superiority of same™ device to preserve platelets. Animals from same and xtra groups retrieved similar rheological profiles and maintained a normal hematocrit compared to no-transfusion control animals. Coagulation profiles stayed within normal range in all groups. No adverse event on animals nor post-mortem sign of thrombosis were identified on autotransfused animals. The same™ device that can therefore be considered as an interesting alternative to conventional centrifugation-based devices. Further experiments are needed to provide evidence of platelets autotransfusion benefits in massive hemorrhagic procedures.

Evaluation of Red Blood Cell Biochemical Markers and Coagulation Profiles Following Cell Salvage in Cardiac Surgery: A Systematic Review and Meta-Analysis

Background: Individuals undergoing cardiac surgery face an increased risk of bleeding, as well as alterations in biochemical and coagulation patterns. Therefore, assessing the effectiveness of systems such as Cell Salvage is necessary to prevent potential surgical complications. Objective: To evaluate the efficacy of Cell Salvage in relation to the biochemical parameters of the red blood series and coagulation, as well as the risk of hemorrhage. Methods: A systematic review, accompanied by a meta-analysis, was executed via an extensive literature exploration encompassing Medline, CINAHL, Scopus, Web of Science, and the Cochrane Library. The inclusion criteria comprised studies in English or Spanish, without year restrictions, conducted in adults and with a randomized controlled trial design. Results: Twenty-six studies were included in the systematic review, involving a total of 2850 patients (experimental group = 1415; control group = 1435). Cell Salvage did not demonstrate superior outcomes compared to allogeneic transfusions in the management of post-surgical hemorrhage, as well as in total blood loss, platelet count, fresh frozen plasma, and fibrinogen. However, Cell Salvage showed a greater effectiveness for hemoglobin (moderate evidence), hematocrit (low evidence), post intervention D-dimer (low evidence), and some coagulation-related parameters (low evidence) compared to allogeneic transfusions. Finally, better results were found in the control group for INR parameters. Conclusions: The use of the Cell Salvage system holds high potential to improve the postoperative levels of biochemical and coagulation parameters. However, the results do not provide definitive evidence regarding its effectiveness for hemorrhage control, platelet count, fresh frozen plasma, and fibrinogen. Therefore, it is recommended to increase the number of studies to assess the impact of the Cell Salvage system on improvements in the red blood cell count and patient coagulation patterns. In addition, protocols should be homogenized, and variables such as the sex of the participants should be taken into account.

Organizational and budget impact model (OBIM) of SAME a new autotransfusion medical device

OBJECTIVES

This study aimed to assess the budget and organizational impact of progressively replacing the intraoperative cell salvage centrifugation-based systems currently installed in French hospitals with the SAME system, a new autotransfusion medical device.

METHODS

An Organizational and Budget Impact Model (OBIM) was developed based on two methodological guidelines issued by the French Health Authority (Haute Autorité de Santé, HAS). The OBIM was also developed based on a pragmatic literature review, hospital data and hospital pharmacists' expertise.

RESULTS

Considering an average hospital cohort of 600 cardio-thoracic surgery patients, with 57% experiencing mild hemorrhages, 23% moderate hemorrhages, and 20% massive hemorrhages, and a SAME market share of 33% in Year 1, the implementation of SAME resulted in significant savings. With an average allogeneic transfusion of 4.19 packed red blood cells (RBC) and 0.62 platelet concentrate per patient based on National Hemovigilance Report of the ANSM (French National Agency for the Safety of Medicines and Health Products) and when using SAME system a reduction of 45% of RBC transfusion associated with a reduction of 60% and 90% of platelet use for moderate and massive hemorrhages respectively, the first year annual saving amounted to €44,601 and the cumulated saving over 5 years to €535,206.

DISCUSSION

This model structure was developed based on overall hospitals' needs and acknowledged guidelines, with inputs based on French literatures and hospital data, so findings were specifics to a context. Among the inputs, the number of annual SAME procedure is not based on device capability but rather on hospital capability with the number of operating rooms used for cardio-thoracic surgery equipped with the device.

CONCLUSIONS

The results of this OBIM demonstrated the economic and organizational benefits of SAME for hospitals. This benefit results mainly of a reduction in the use of allogeneic blood products (RBCs, platelets).

Combined Platelet and Red Blood Cell Recovery during On-pump Cardiac Surgery Using same™ by i-SEP Autotransfusion Device: A First-in-human Noncomparative Study (i-TRANSEP Study)

BACKGROUND

Centrifugation-based autotransfusion devices only salvage red blood cells while platelets are removed. The same™ device (Smart Autotransfusion for ME; i-SEP, France) is an innovative filtration-based autotransfusion device able to salvage both red blood cells and platelets. The authors tested the hypothesis that this new device could allow a red blood cell recovery exceeding 80% with a posttreatment hematocrit exceeding 40%, and would remove more than 90% of heparin and 75% of free hemoglobin.

METHODS

Adults undergoing on-pump elective cardiac surgery were included in a noncomparative multicenter trial. The device was used intraoperatively to treat shed and residual cardiopulmonary bypass blood. The primary outcome was a composite of cell recovery performance, assessed in the device by red blood cell recovery and posttreatment hematocrit, and of biologic safety assessed in the device by the washout of heparin and free hemoglobin expressed as removal ratios. Secondary outcomes included platelet recovery and function and adverse events (clinical and device-related adverse events) up to 30 days after surgery.

RESULTS

The study included 50 patients, of whom 18 (35%) underwent isolated coronary artery bypass graft, 26 (52%) valve surgery, and 6 (12%) aortic root surgery. The median red blood cell recovery per cycle was 86.1% (25th percentile to 75th percentile interquartile range, 80.8 to 91.6) with posttreatment hematocrit of 41.8% (39.7 to 44.2). Removal ratios for heparin and free hemoglobin were 98.9% (98.2 to 99.7) and 94.6% (92.7 to 96.6), respectively. No adverse device effect was reported. Median platelet recovery was 52.4% (44.2 to 60.1), with a posttreatment concentration of 116 (93 to 146) · 109/l. Platelet activation state and function, evaluated by flow cytometry, were found to be unaltered by the device.

CONCLUSIONS

In this first-in-human study, the same™ device was able to simultaneously recover and wash both platelets and red blood cells. Compared with preclinical evaluations, the device achieved a higher platelet recovery of 52% with minimal platelet activation while maintaining platelet ability to be activated in vitro.

EDITOR’S PERSPECTIVE

The Effect of Cell Salvage on Bleeding and Transfusion Needs in Cardiac Surgery

Introduction. Cell salvaging is well established in the blood management of cardiac patients, but there remain some concerns about its effects on perioperative bleeding and transfusion variables. This randomized controlled study investigated the potential effects of the centrifuged end-product on bleeding, transfusion rates, and other transfusion-related variables in adult cardiac surgery patients submitted to extracorporeal circulation. Materials and Methods. Patients were randomly chosen to receive (cell-salvage group, 99 patients) or not to receive (control group, 110 patients) the centrifuged product of a cell salvage apparatus. Bleeding and transfusion rates according to the universal definition of perioperative bleeding (UDPB) classification, postoperative hemoglobin, coagulation, and oxygenation indices were recorded and compared between the groups. Results. Both groups had almost identical bleeding and transfusion rates (median value: 2 units of red blood cells (RBC) and no units of fresh frozen plasma (FFP) and platelets (PLT) for both groups, $p>0.05$ ). Patients in the cell-salvage group presented slightly higher hemoglobin concentrations (10.6 ± 1.1 vs. 10.1 ± 1.7 g/dL, $p<0.05$ , respectively) and a tendency towards better oxygenation indices (PaO2/FiO2: 241 ± 94 vs. 207 ± 84, $p=0.013$ ) in the postoperative period albeit with a tendency for prolongation of prothrombin time (INR: 1.31 ± 0.18 vs. 1.26 ± 0.12, $p=0.008$ ). Conclusion. Within the study’s constraints, the perioperative use of the cell salvage concentrate does not seem to affect bleeding or transfusion variables, although it could probably ameliorate postoperative oxygenation in adult cardiac surgery patients. A tendency to promote coagulation disturbances was detected.

Recovery of platelet-rich red blood cells and acquisition of convalescent plasma with a novel gravity-driven blood separation device

Objectives

Our objectives were to determine the separation characteristics and blood product quality of a gravity‐driven microfiltration blood separation system (HemoClear, The Netherlands).

Background

A range of centrifugal blood separation devices, including intraoperative cell salvage devices (cell savers) and apheresis machines, are available to assist in preparing both allogenic and autologous blood products. These devices are expensive to operate and require extensive training.

Methods and Materials

Nine whole blood units were collected under standard conditions and analysed for haematological parameters, thromboelastographic properties, platelet morphology and activation, and red blood cell (RBC) deformability and morphology. Three whole blood units were separated by means of the HemoClear device, into a liquid and cellular component. The cellular component was diluted with SAGM and cold stored for 14 days. To simulate cell salvage six whole blood units were diluted with isotonic saline, followed by multiple HemoClear separation rounds.

Results

The recovery of both RBCs (100 ± 1.6%) and white blood cells (99 ± 4.5%) after undiluted filtration were very high, while platelet recovery was high (83 ± 3.0%). During the filtration, and cold storage after filtration storage both the non‐deformable RBC fraction and the RBC maximum elongation remained stable. Parameters of thromboelastography indicated that platelets remain functional after filtration and after 7 days of cold storage. In the cell salvage simulation the total protein load in the cellular fraction was reduced by 65 ± 4.1% after one washing round and 84 ± 1.9% after two consecutive washing rounds.

Conclusion

The novel blood filter studied effectively separates whole blood into diluted plasma and platelet‐rich RBCs. Moreover, the device effectively washed diluted whole blood, driving over 80% of proteins to the liquid component.

Combined Platelet and Erythrocyte Salvage: Evaluation of a New Filtration-based Autotransfusion Device

BACKGROUND

The SAME device (i-SEP, France) is an innovative filtration-based autotransfusion device able to salvage and wash both red blood cells and platelets. This study evaluated the device performances using human whole blood with the hypothesis that the device will be able to salvage platelets while achieving a erythrocyte yield of 80% and removal ratios of 90% for heparin and 80% for major plasma proteins without inducing signification activation of salvaged cells.

METHODS

Thirty healthy human whole blood units (median volume, 478 ml) were diluted, heparinized, and processed by the device in two consecutive treatment cycles. Samples from the collection reservoir and the concentrated blood were analyzed. Complete blood count was performed to measure blood cell recovery rates. Flow cytometry evaluated the activation state and function of platelets and leukocytes. Heparin and plasma proteins were measured to assess washing performance.

RESULTS

The global erythrocyte yield was 88.1% (84.1 to 91.1%; median [25th to 75th]) with posttreatment hematocrits of 48.9% (44.8 to 51.4%) and 51.4% (48.4 to 53.2%) for the first and second cycles, respectively. Ektacytometry did not show evidence of erythrocyte alteration. Platelet recovery was 36.8% (26.3 to 43.4%), with posttreatment counts of 88 × 109/l (73 to 101 × 109/l) and 115 × 109/l (95 to 135 × 109/l) for the first and second cycles, respectively. Recovered platelets showed a low basal P-selectin expression at 10.8% (8.1 to 15.2%) and a strong response to thrombin-activating peptide. Leukocyte yield was 93.0% (90.1 to 95.7%) with no activation or cell death. Global removal ratios were 98.3% (97.8 to 98.9%), 98.2% (96.9 to 98.8%), and 88.3% (86.6 to 90.7%) for heparin, albumin, and fibrinogen, respectively. The processing times were 4.4 min (4.2 to 4.6 min) and 4.4 min (4.2 to 4.7 min) for the first and second cycles, respectively.

CONCLUSIONS

This study demonstrated the performance of the SAME device. Platelets and red blood cells were salvaged without significant impact on cell integrity and function. In the meantime, leukocytes were not activated, and the washing quality of the device prevented reinfusion of high concentrations of heparin and plasma proteins.

EDITOR’S PERSPECTIVE

Preoperative Anemia is Associated with Increased Intraoperative Mortality in Patients Undergoing Cardiac Surgery

Objectives

We sought to investigate the incidence of preoperative anemia in cardiac surgery and its association with outcomes.

Methods

A retrospective review of clinical, laboratory, and transfusion data for all patients who underwent cardiac surgery at Sultan Qaboos University Hospital between 2008 and 2014 was performed. Patients were divided into two groups, anemic and non-anemic, with anemia defined as hemoglobin levels < 13 g/dL (males) and < 12 g/dL (females). Clinical variables were compared using chi-square and independent t-test. Factors influencing preoperative mortality were analyzed using multivariate binary logistics regression.

Results

A total of 599 patients (69.9% males and 30.1% females) were included in the study; 69.3% underwent coronary artery bypass surgery. Preoperative anemia was found in 76.1% of females and 26.7% of male patients. Rates of intraoperative red blood cell transfusions were higher among anemic patients (75.9% vs. 52.3%, p < 0.001). Anemic patients had a worse risk profile with higher incidence of diabetes mellitus (53.8% vs. 38.9%, p < 0.001), congestive heart failure (51.4% vs. 28.3%, p < 0.001), arrhythmia (16.5% vs. 8.6%, p = 0.004), and cerebrovascular disease (10.0% vs. 4.9%, p = 0.015). In addition, they had a higher risk of overall mortality (6.4% vs. 2.6%, p = 0.023). Preoperative anemia remained a risk factor for intraoperative mortality after logistic regression (odds ratio = 4.08, 95% confidence interval: 1.43–11.66; p = 0.009).

Conclusions

Preoperative anemia in cardiac surgery is independently associated with increased intraoperative mortality and early readmission rates post-surgery.

Impact of Blood Transfusion on Troponin I Levels and Outcomes after Cardiac Surgery: A Cohort Study

Objectives

Increased cardiac troponin I (TI) has been suggested to be a sensitive indicator of intraoperative myocardial injury. We investigated the association of transfusion on TI levels post-surgery and outcomes in patients undergoing elective cardiac surgeries.

Methods

We conducted a retrospective review of 542 patients. Patients were divided into two groups based on TI levels at 24 hours (TI24) (> 6.5 µg/L vs. ≤ 6.5 µg/L). The impact of transfusion on TI levels was estimated using logistic regression and adjusted for using a multivariable model that included aortic cross-clamp time and preoperative ejection fraction. The effect of TI on the clinical outcomes was examined.

Results

Red blood cell (RBC) transfusion was found to be associated with high TI levels (odds ratio (OR) = 2.33, p = 0.007, 95% confidence interval (CI): 1.30–4.30). A trend was observed when aortic cross-clamp time and preoperative ejection fraction were adjusted for (OR = 2.06, p = 0.080, 95% CI: 0.90–4.70). An association was found between aortic cross-clamp time and high TI levels in the multivariable model (OR = 1.01, p = 0.028, 95% CI: 1.00–1.02). Elevated TI levels was associated with higher mortality (OR = 4.15, p = 0.017, 95% CI: 1.29–13.08), renal failure (OR = 2.99, p = 0.004, 95% CI: 1.41–6.32), and increased length of stay in-hospital (OR = 4.50, p = 0.020, 95% CI: 0.69–8.30).

Conclusions

RBC transfusion is associated with increased TI24 post-cardiac surgery and worse outcomes, albeit a confounding effect cannot be excluded. Larger studies are required to confirm these findings.

Impact of platelet pathogen inactivation on blood component utilization and patient safety in a large Austrian Regional Medical Centre

BACKGROUND

In clinical studies, pathogen inactivation (PI) of platelet concentrates (PC) with amotosalen and UVA light did not impact patient risk for haemorrhage but may affect transfusion frequency and component utilization. We evaluated the influence of platelet PI on PC, red cell concentrate (RCC) and plasma use and safety in routine practice in a large regional hospital.

STUDY DESIGN AND METHODS

Comparative effectiveness of conventional vs. PI-treated PC was analysed during two 21-month periods, before and after PI implementation.

RESULTS

Similar numbers of patients were transfused in the pre-PI (control, 1797) and post-PI (test, 1694) periods with comparable numbers of PC (8611 and 7705, respectively). The mean numbers of PC per patient transfused (4·8 vs. 4·5, P = 0·43) were not different but days of PC support (5·9 vs. 5·0, P < 0·01) decreased. Most patients received RCC (86·8% control vs. 84·8% test, P = 0·90) with similar mean numbers transfused (10·8 vs. 10·2 RCC, P = 0·22), and fewer patients (55·4% control vs. 44·7% test, P < 0·01) received less plasma units (mean 9·9 vs. 7·8, respectively, P < 0·01) in the test period. The frequencies of transfusion-related adverse events (AE) were comparable (1·3% vs. 1·4%, P = 0·95). Analysis of haematology-oncology (522 control, 452 test), cardiac surgery (739 control, 711 test), paediatric (157 control, 130 test) and neonate (23 control, 20 test) patients revealed no increase in PC, plasma and RCC utilization, or AE.

CONCLUSION

Component utilization and patient safety were not impacted by adoption of PI for PC. RCC use per patient was comparable, suggestive of no increase in significant bleeding.