Clinical Utility of Autologous Salvaged Blood: a Review

The Importance of Cell Saver Usage in Complex Endovascular Repair of Thoraco-Abdominal Aortic Aneurysms

AIM

The use of the cell-saver is well established in open aneurysm repair, however, its role in endovascular repair is yet to be determined. The aim of this study was to analyze the effects of cell-saver usage in patients undergoing complex endovascular procedures.

MATERIALS AND METHODS

Single-center retrospective cohort study including consecutive patients undergoing fenestrated and/or branched repair for the treatment of thoracoabdominal and complex abdominal aortic aneurysms between January 2019 and December 2022. The cell-saver was a standard part of the intraoperative setup of these procedures and its use was readily available. The primary endpoint was the percentage of patients in which autologous blood collected was transfused (CSBT), alongside the usable amount obtained. Secondary endpoints included mean blood loss, postoperative haemoglobin levels and 30-day mortality.

RESULTS

A total of 170 patients (77.1% male, mean age 71.2 ± 9.2 years) were included, with a median blood loss of 700mL (IQR 400-1200mL). A total of 96 patients received some kind of blood transfusion (BT) (56.5%): 35 (20.6%) allogenic BT, 31 (18.2%) CSBT only and 30 (17.6%) a combination of both. In total, 61 patients (35.9%, or 63.5% of all patients requiring BTs) received CSBT, with a median usable blood volume of 282mL (IQR, 194.5 - 508mL). Thirty-day mortality was similar in both groups. Although the CSBT group had lower intraoperative hemoglobin values (9.25 ± 1.55 vs. 10.36 ± 1.88 mg/dL; p<0.001), both groups presented similar postoperative hemoglobin levels.

CONCLUSION

Blood loss during complex endovascular repair is not insignificant. In this cohort, over 50% of included patients required some kind of BT, 32.3% of which received exclusively CSBT while 31.3% had supplementary CSBT alongside allogenic BT. This data showcases its potential role in these repairs, paving the way for its standardization in the intraoperative setup of these complex procedures.

Effect of intraoperative blood transfusion during maternal cesarean section on serum electrolytes and inflammatory response plus cellular immune response: A retrospective study

Analyzing the effect of intraoperative autotransfusion on serum electrolytes, inflammatory response and cellular immune response in puerperae undergoing cesarean section. This study is a retrospective study of 60 women who underwent cesarean section in our hospital from January 2022 to January 2023. The subjects were divided into 2 groups according to the blood transfusion mode of the patients. The differences in blood transfusion volume, blood transfusion volume, serum electrolyte, inflammatory response, cellular immune function, coagulation function and prognosis were compared between the 2 groups. The intraoperative blood transfusion volume, postoperative feeding time, the activity time since getting out of bed, the time of physical recovery and hospital stay in the observation group were lower compared to those of the control group, but the intraoperative crystal infusion volume and the colloid infusion volume in the observation group were higher compared to those of the control group (P < .05). Ca2+ concentrations of the observation group and the control group were lower compared with those of their same groups before surgery (P < .05), however, there were no statistically significant differences in the comparison of the Ca2+ concentrations between the observation group and the control group (P > .05). At 1d postoperatively, IL-1β, IL-6 and granulocyte-macrophage colony-stimulating factor (GM-CSF) were all higher (P < .05) and CD3+, CD4+ and CD4+/CD8+ were all lower (P < .05) in the observation group and the control group compared with those of their same groups before surgery. The IL-1 β, IL-6, and GM-CSF of the observation group were decreased compared to those of the control group (P < .05) and CD3+, CD4+, CD4+/CD8+ of the observation group were elevated compared to those of the control group (P < .05). Both autotransfusion and allogeneic blood transfusions during maternal cesarean section can attenuate the inflammatory response and have no significant inhibition of coagulation, and autotransfusion have less effect on the cellular immune response, are more effective in attenuating the inflammatory response, and significantly improve prognosis, although changes in Ca2+ concentration after transfusion require attention.

The effectiveness of cell salvage in extracorporeal circulation surgeries in relation to use of health resources after use: A systematic review and meta-analysis

Background

Alternatives to allogeneic blood transfusions are sought for resource management reasons and it is necessary to investigate the efficiency and efficacy on Cell Salvage use. The objective of this study is to analyze the effectiveness of the Cell Salvage system in addressing factors related to healthcare service utilization that may lead to increased healthcare expenditure.

Methods

A systematic review with meta-analysis was conducted through literature search in Medline, CINAHL, Scopus, Web of Science, and Cochrane Library. Inclusion criteria were studies in English/Spanish, without year restriction and Randomized Controlled Trials design, conducted in adults.

Results

Twenty-six studies were included in the systematic review, involving a total of 4781 patients (nexperimental group = 2365; ncontrol group = 2416). Significant differences favored the Cell Salvage system in units of transfused Red Blood Cells, in terms of units (p = 0.04; SMD = -0.42 95 % CI = -0.83 to -0.02) and individuals (p = 0.001; RR = 0.71, 95 % CI = 0.60 to 0.84) transfused. No significant differences were found in ICU (p = 0.93) and hospital stay duration (p = 0.21), number of reoperations (p = 0.68), and number of units and individuals transfused in terms of platelets (p > 0.05).

Conclusions

Cell Salvage use holds high potential for reducing healthcare costs and indirectly contributing to improving blood and blood product reserves within blood banks. Results obtained thus far do not provide definitive evidence regarding the duration of hospital stay, ICU stay, need for reoperation, or the quantity of transfused platelets. Therefore, it is recommended to increase the number of studies to assess the impact on the economic models of the Cell Salvage system.

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 Challenges of Spinal Surgery Requiring Ventral Decubitus in the Critical Trauma Patient on Extracorporeal Membrane Oxygenation: A Case Report

Extracorporeal membrane oxygenation (ECMO) provides a bypass of the lungs, ensuring blood oxygenation and carbon dioxide removal in cases of respiratory failure. The nature of the device itself creates many perioperative challenges, including fluid management and the management of anticoagulation. Surgery via the posterior approach for an unstable spinal fracture requiring the ventral decubitus position comes with its own set of difficulties, among which are the need for stability and craniocaudal alignment when rotating the patient, the risk of increased abdominal pressure, and the damage to vulnerable soft tissues like the eyes, nose, and others. The combination of these two situations creates a synergistic effect, which adds to the difficulty of the management of the situation and requires a personalized, multidisciplinary approach. We present a case of a critical trauma patient who was on venovenous ECMO as a consequence of refractory respiratory hypoxemia with an unstable mid-thoracic spinal fracture requiring surgical intervention via the posterior approach (demanding intra-operative ventral decubitus).

Everyday Cardiac Surgery in Jehovah's Witnesses of Typically Advanced Age: Clinical Outcome and Matched Comparison

BACKGROUND AND OBJECTIVES

Jehovah's Witnesses (JW) reject the transfusion of blood components based on their religious beliefs, even if they are in danger of harm or death. In cardiac surgery, this significantly reduces the margin of safety and leads to ethical conflicts. Informed consent should be carefully documented and the patient's family should be involved. This study aims to compare the postoperative course of JW who underwent major cardiac surgery with a similar population of non-Witnesses (NW).

PATIENTS AND METHODS

Demographic, procedural, and postoperative data of all consecutive JW who underwent cardiac surgery at our institution were obtained from the records. They were compared with a propensity-score-matched group of NW. Anemic JW were treated with erythropoietin and/or iron as needed. Cardiac surgery was performed by experienced surgeons using median sternotomy and cardiopulmonary bypass. Common blood-sparing techniques were routinely used. Periprocedural morbidity and mortality were statistically evaluated for both groups.

RESULTS

A total of 32 JW and 64 NW were part of the matched dataset, showing no demographic or procedural differences. EPO was used preoperatively in 34.4% and postoperatively in 15.6% of JW but not in NW. Preoperative hemoglobin levels were similar (JW, 8.09 ± 0.99 mmol/L; NW, 8.18 ± 1.06; p = 0.683). JW did not receive any transfusions except for one who revoked, while NW transfusion rates were 2.5 ± 3.1 units for red cells (p < 0.001) and 0.3 ± 0.8 for platelets (p = 0.018). Postoperative levels differed significantly for hemoglobin (JW, 6.05 ± 1.00 mmol/L; NW, 6.88 ± 0.87; p < 0.001), and hematocrit (JW, 0.29 ± 0.04; NW, 0.33 ± 0.04; p < 0.001) but not for creatinine. Early mortality was similar (JW, 6.3%; NW, 4.7%; p = 0.745). There were more pacemakers and pneumonias in JW, while all other postoperative conditions were not different.

CONCLUSIONS

Real-world data indicate that Jehovah's Witnesses can safely undergo cardiac surgery provided that patients are preconditioned and treated by experienced surgeons who use blood-saving strategies. Postoperative anemia is observed but does not translate into a worse clinical outcome. This is consistent with other studies. Finally, the results of this study suggest that all patients should benefit from optimal pretreatment and blood-sparing strategies in cardiac surgery, not just Jehovah's Witnesses.

Turbulence in surgical suction heads as detected by MRI

BACKGROUND

Blood loss is common during surgical procedures, especially in open cardiac surgery. Allogenic blood transfusion is associated with increased morbidity and mortality. Blood conservation programs in cardiac surgery recommend re-transfusion of shed blood directly or after processing, as this decreases transfusion rates of allogenic blood. But aspiration of blood from the wound area is often associated with increased hemolysis, due to flow induced forces, mainly through development of turbulence.

METHODS

We evaluated magnetic resonance imaging (MRI) as a qualitative tool for detection of turbulence. MRI is sensitive to flow; this study uses velocity-compensated T1-weighted 3D MRI for turbulence detection in four geometrically different cardiotomy suction heads under comparable flow conditions (0-1250 mL/min).

RESULTS

Our standard control suction head Model A showed pronounced signs of turbulence at all flow rates measured, while turbulence was only detectable in our modified Models 1-3 at higher flow rates (Models 1 and 3) or not at all (Model 2).

CONCLUSIONS

The comparison of flow performance of surgical suction heads with different geometries via acceleration-sensitized 3D MRI revealed significant differences in turbulence development between our standard control Model A and the modified alternatives (Models 1-3). As flow conditions during measurement have been comparable, the specific geometry of the respective suction heads must have been the main factor responsible. The underlying mechanisms and causative factors can only be speculated about, but as other investigations have shown, hemolytic activity is positively associated with degree of turbulence. The turbulence data measured in this study correlate with data from other investigations about hemolysis induced by surgical suction heads. The experimental MRI technique used showed added value for further elucidating the underlying physical phenomena causing blood damage due to non-physiological flow.

Error traps in Pediatric Patient Blood Management in the Perioperative Period

Patient blood management is a patient-centered evidence-based approach to improve patient outcomes by harnessing the patient's own hematopoietic system to optimize blood health while promoting patient safety and empowerment. Perioperative patient blood management is a standard of care in adult medicine, yet it is not commonly accepted in pediatrics. Raising awareness may be the first step in improving perioperative care for the anemic and/or bleeding child. This article highlights five preventable perioperative blood conservation error traps for children. The goal is to provide practical clinical guidance to improve preoperative diagnosis and treatment of anemia, facilitate recognition and treatment of massive hemorrhage, reduce unnecessary allogeneic blood transfusions, and decrease associated complications of anemia and blood component transfusions utilizing a patient/family-centered informed consent and shared decision-making approach.

A framework for perioperative care for lower extremity vascular bypasses: A Consensus Statement by the Enhanced Recovery after Surgery (ERAS®) Society and Society for Vascular Surgery

The Society for Vascular Surgery and the Enhanced Recovery After Surgery (ERAS) Society formally collaborated and elected an international, multi-disciplinary panel of experts to review the literature and provide evidence-based suggestions for coordinated perioperative care for patients undergoing infrainguinal bypass surgery for peripheral artery disease. Structured around the ERAS core elements, 26 suggestions were made and organized into preadmission, preoperative, intraoperative, and postoperative sections.

Transfusion-free Strategies in Liver and Pancreatic Surgery: A Predictive Model of Blood Conservation for Transfusion Avoidance in Mainstream Populations

OBJECTIVE

The objective of this study is to (1) describe the techniques and prove the feasibility of performing complex hepatobiliary and pancreatic surgery on a Jehovah Witness (JW) population.  (2) Describe a strategy that offsets surgical blood loss by the manipulation of circulating blood volume to create reserve whole blood upon anesthesia induction.

BACKGROUND

Major liver and pancreatic resections often require operative transfusions. This limits surgical options for patients who do not accept major blood component transfusions. There is also growing recognition of the negative impact of allogenic blood transfusions.

METHODS

A 23-year, single-center, retrospective review of JW patients undergoing liver and pancreatic resections was performed. We describe perioperative management and patient outcomes. Acute normovolemic hemodilution (ANH) is proposed as an important strategy for offsetting blood losses and preventing the need for blood transfusion. A quantitative mathematical formula is developed to provide guidance for its use.

RESULTS

One hundred one major resections were analyzed (liver n=57, pancreas n=44). ANH was utilized in 72 patients (liver n=38, pancreas n=34) with median removal of 2 units that were returned for hemorrhage as needed or at the completion of operation. There were no perioperative mortalities. Morbidity classified as Clavien grade 3 or higher occurred in 7.0% of liver resection and 15.9% of pancreatic resection patients.

CONCLUSIONS

Deliberate perioperative management makes transfusion-free liver and pancreatic resections feasible. Intraoperative whole blood removal with ANH specifically preserves red cell mass, platelets, and coagulation factors for timely reinfusion. Application of the described JW transfusion-free strategy to a broader general population could lessen blood utilization costs and morbidities.

Intraoperative cell salvage using swab wash and serial thromboelastography in elective abdominal aortic aneurysm surgery involving massive blood loss

The loss of 50% blood volume is one accepted definition of massive haemorrhage, which ordinarily would trigger the massive transfusion protocol, involving the administration of high ratios of fresh frozen plasma and platelets to allogeneic red cells. We investigated 53 patients who experienced >50% blood loss during open elective abdominal aortic aneurysm surgery to assess allogeneic blood component usage and coagulopathy. Specialist patient blood management practitioners used a tailored cell salvage technique including swab wash to maximise blood return. We assessed the proportion of patients who did not require allogeneic blood components and develop evidence of coagulopathy by thromboelastography (TEG) parameters. Blood loss was 50%-174% (mean [SD] 68% [27%]) of blood volume. The mean (SD) intraoperative decrease in haemoglobin concentration, assessed by arterial blood gas analysis, was 5 (13) g/l. No patient received allogeneic red cells intraoperatively. Four of the 53 (8%) patients received blood components in the first 24 h postoperatively at the anaesthetists' discretion. No patient had intraoperative TEG changes indicative of fibrinolysis or coagulopathy. The 30-day mortality was 2% (one of 53). Reduction of allogeneic transfusion is one aim of patient blood management techniques. We have demonstrated virtual avoidance of allogeneic blood product transfusion despite massive blood loss. These data show possible alternatives to the current massive transfusion protocols to the management of elective vascular surgical patients.

Perioperative Tracking of Intravenous Iron in Patients Undergoing On-Pump Cardiac Surgery: A Prospective, Single-Center Pilot Trial

BACKGROUND

Preoperative intravenous iron administration is a frequently used patient blood management procedure. If the timeframe of intravenous iron administration before surgery is short, (1) the concentration of the intravenous iron compound might still be high in patients' plasma when undergoing surgery and (2) this iron in patients' plasma is at risk to be lost due to blood loss. The aim of the current study was, therefore, to track the iron compound ferric carboxymaltose (FCM) before, during, and after cardiac surgery requiring cardiopulmonary bypass, with an emphasis on intraoperative iron losses in shed blood and potential recovery through autologous cell salvage.

METHODS

Concentrations of FCM were analyzed in patients' blood using a hyphenation of liquid chromatography and inductively coupled plasma-mass spectrometry to distinguish between pharmaceutical compound FCM and serum iron. In this prospective, single-center pilot trial, 13 anemic and 10 control patients were included. Anemic patients with hemoglobin levels ≤12/13 g/dL in women and men were treated with 500 milligrams (mg) intravenous FCM 12 to 96 hours before elective on-pump cardiac surgery. Patients' blood samples were collected before surgery and at days 0, 1, 3, and 7 after surgery. One sample each was taken of the cardiopulmonary bypass, the autologous red blood cell concentrate generated by cell salvage, and the cell salvage disposal bag.

RESULTS

Patients who had received FCM <48 hours before surgery had higher FCM serum levels (median [Q1-Q3], 52.9 [13.0-91.6]) compared to ≥48 hours (2.1 [0.7-5.1] µg/mL, P = .008). Of 500-mg FCM administered <48 hours, 327.37 (257.96-402.48) mg were incorporated compared to administration ≥48 hours with 493.60 (487.78-496.70) mg. After surgery, patients' plasma FCM concentration in the FCM <48 hours group was decreased (-27.1 [-30 to -5.9] µg/mL). Little FCM was found in the cell salvage disposal bag (<48 hours, 4.2 [3.0-25.8] µg/mL, equivalent to 29.0 [19.0-40.7] mg total; equivalent to 5.8% or 1/17th of the 500 mg FCM initially administered), almost none in the autologous red blood cell concentrate (<48 hours, 0.1 [0.0-0.43] µg/mL).

CONCLUSIONS

The data generate the hypotheses that nearly all FCM is incorporated into iron stores with administration ≥48 hours before surgery. When FCM is given <48 hours of surgery, the majority is incorporated into iron stores by the time of surgery, although a small amount may be lost during surgical bleeding with limited recovery by cell salvage.

Utilization and cost of cell salvage in minimally invasive myomectomy

OBJECTIVE

To assess the utilization and cost of intraoperative cell salvage (ICS) in minimally invasive myomectomy.

STUDY DESIGN

Retrospective cohort study of patients who underwent minimally invasive myomectomy at a quaternary care academic hospital. Patients were classified into: ICS setup vs no ICS setup, ICS setup with reinfusion vs ICS setup without reinfusion.

RESULTS

Of 382 patients who underwent minimally invasive myomectomy, 67 (17.5 %) had ICS setup, 30 (44.8 %) of those patients reinfused. Median volume of reinfusion per patient was 300 mL (range 125-1000 mL). Patients who ultimately underwent ICS reinfusion, compared to those with ICS setup only, had significantly larger mean maximum fibroid size (9.8 cm vs 8.0 cm, p = 0.02), higher median total specimen weight (367 vs 304 g, p = 0.03), higher median estimated blood loss (575 vs 300 mL, p < 0.0001), longer mean operative time (261 vs 215 min, p = 0.04). No perioperative complications were associated with ICS. Higher costs are associated with universal use or complete lack of ICS; lowest cost is associated with ICS setup only for those ultimately reinfused.

CONCLUSION

ICS might reduce requirements for allogeneic blood transfusions in patients undergoing minimally invasive myomectomy, and may contribute to cost savings. Uterine and maximum fibroid sizes are possible preoperative indicators for patients who require cell salvage reinfusion.

Risk factors associated with positive bacterial culture in salvaged red blood cells during cardiac surgery and postoperative infection incidence: A prospective cohort study

Background

This study was designed to explore factors associated with the incidence of positive bacterial culture of salvaged red blood cells (sRBCs) recovered with a Cell Saver instrument during cardiac surgery and the impact of such positive outcomes on postoperative infection-related morbidity.

Methods

The cohort study enrolled 204 patients scheduled for cardiac surgery with intraoperative blood cell salvage and retransfusion from July 2021 to July 2022. These patients were stratified into two groups based on intraoperative sRBCs bacterial culture results: culture (+) and culture (-) groups. Preoperative and intraoperative variables were compared between these groups aim to detect possible predictors of positive culture in sRBCs. In addition, differences in postoperative infection-related morbidity and other clinical outcomes were compared between these groups.

Results

Of these patients, 49% were sRBCs culture (+), with Staphylococcus epidermidis as the most commonly identified pathogen. Risk factors independently associated with the risk of positive culture in sRBCs included BMI ≥25 kg/m², a history of smoking, an operative duration ≥277.5 min, the higher number of staff in the operating room and higher surgical case order. Patients in the sRBCs culture (+) group exhibited a longer average ICU stay [3.5 days (2.0-6.0) vs. 2 days (1.0-4.0), P < 0.01], a longer duration of ventilation [20.45 h (12.0-17.8) vs. 13 h (11.0-17.0, P = 0.02)], underwent more allogeneic blood transfusions, exhibited higher transfusion-related costs [2,962 (1,683.0-5,608.8) vs. 2,525 (1,532.3-3,595.0), P = 0.01], and had higher rates of postoperative infections (22 vs. 9.6%, P = 0.02) as compared to patients in the sRBCs culture (-) group. In addition, culture (+) in sRBCs was an independent risk factor for postoperative infection (OR 2.62, 95% CI 1.16-5.90, P = 0.02).

Conclusion

Staphylococcus epidermidis was the most common pathogen detected in sRBCs in the culture (+) group in this study, identifying it as a potential driver of postoperative infection. Positive sRBCs culture may contribute to postoperative infection and its incidence was significantly associated with patient BMI, history of smoking, operative duration, the number of staff in the operating room and surgical case order.

Autologous blood resuscitation for large animals in a research setting using the Hemafuse device: Preliminary data of device use for controlled and real-world hemorrhage

Introduction

New low-cost technologies are needed to salvage lost blood in low-resource settings and large animal laboratories. The Hemafuse device is a simple mechanical device that can recover lost blood during surgery. The aim of this study is to assess the feasibility of this device for resuscitating large animals with controlled and unintended hemorrhage and to provide device considerations for use in this context.

Methods

This study had two experimental components: (1) the Hemafuse device was kept on-shelf and used as needed to assess real-world use for unintended hemorrhage during experiments, and (2) animals underwent a controlled hemorrhage protocol, where four anesthetized swine underwent aortic and external jugular vein catheterization for pressure monitoring. Animals were hemorrhaged into the pelvis, and the Hemafuse device was used to suction the blood through a filter and pushed into a heparinized bag for subsequent retransfusion. Blood samples were collected at baseline, hemorrhage, within the device, and post-retransfusion and laboratory tests were performed.

Results

Animals that underwent controlled hemorrhage had a baseline mean arterial pressure of 83.6 ± 7.8 mmHg, and central venous pressure of 12.8 ± 1.9 mmHg, with expected changes throughout hemorrhage and resuscitation. Following resuscitation, pH was similar to baseline (7.39 ± 0.05 vs. 7.31 ± 0.03, p = 0.24). Lactate increased throughout the experiment with no significant differences after autotransfusion compared to baseline (2.7 ± 0.7 vs. 4.1 ± 1.4 mmol/L, p = 0.37). There were no significant changes in metabolic physiology. Compared to baseline, the hemoglobin (7.8 ± 2.4 vs. 7.3 ± 1.8 g/dL, p = 0.74), hematocrit (23% ± 6.9 vs. 21.3% ± 5.6, p = 0.71), and activated clotting time (268.5 ± 44.5 vs. 193 ± 24.6 s, p = 0.35) were similar after retransfusion. When used for unintended hemorrhage, the animals were resuscitated using the device with a mean time to retransfusion time of 128.7 ± 13.3 s and 100% survival throughout the experiment.

Conclusion

The Hemafuse device is feasible and efficacious for supporting large animal resuscitation. This is preliminary evidence that the device is a low-risk and low-cost off-the-shelf option for resuscitation using autologous blood with no significant effect on physiology post-retransfusion. We recommend that research laboratories consider the Hemafuse device for emergency use, particularly for highly invasive surgical laboratories where banked blood is not readily available.

Patient Blood Management in Vascular Surgery

Patient blood management (PBM) is an evidence-based, multidisciplinary approach aimed at appropriately allocating blood products to patients requiring transfusion while simultaneously minimizing inappropriate transfusions. The 3 pillars of patient blood management are optimizing erythropoiesis, minimizing blood loss, and optimizing physiological reserve of anemia. Benefits seen from PBM include limiting hospital costs and mitigating harm from numerous risks of transfusion.

Assessment of thermally stabilized electrospun poly(vinyl alcohol) materials as cell permeable membranes for a novel blood salvage device

The use of Intraoperative Cell Salvage (ICS) is currently limited in oncological surgeries, due to safety concerns associated with the ability of existing devices to successfully remove circulating tumour cells. In this work, we present the first stages towards the creation of an alternative platform to current cell savers, based on the extremely selective immunoaffinity membrane chromatography principle. Non-woven membranes were produced via electrospinning using poly(vinyl alcohol) (PVA), and further heat treated at 180 °C to prevent their dissolution in aqueous environments and preserve their fibrous morphology. The effects of the PVA degree of hydrolysis (DH) (98 % vs 99 %), method of electrospinning (needleless DC vs AC), and heat treatment duration (1-8 h) were investigated. All heat treated supports maintained their cytocompatibility, whilst tensile tests indicated that the 99 % hydrolysed DC electrospun mats were stronger compared to their 98 % DH counterparts. Although, and at the described conditions, AC electrospinning produced fibres with more than double the diameter compared to those from DC electrospinning, it was not chosen for subsequent experiments because it is still under development. Evidence of unimpeded passage of SY5Y neuroblastoma cells and undiluted defibrinated sheep's blood in flow-through filtration experiments confirmed the successful creation of 3D networks with minimum resistance to mass transfer and lack of non-specific cell binding to the base material, paving the way for the development of novel, highly selective ICS devices for tumour surgeries.

Development and Validation of a Nomogram to Predict the Risk of Blood Transfusion in Orthognathic Patients

OBJECTIVE

This study aims to establish a nomogram to predict the probability of blood transfusion in patients with preoperative autologous blood donation before orthognathic surgery.

METHODS

The authors conducted a retrospective case-control study on consecutive orthognathic patients with preoperative autologous blood donation from January 2014 to December 2020. The outcome variable was the actual transfusion of autologous blood (ATAB). Predictors included patients' demographics, preoperative blood cell test, vital signs, American Society of Anesthesiologists classification, surgical procedure, operation duration, and blood loss. Univariable and multivariable logistic regressions were performed to identify independent risk factors associated with ATAB. A nomogram was constructed to predict the risk for ATAB. The performance of the nomogram was evaluated using the area under the receiver operating characteristic curve, calibration curve and the consistency index.

RESULTS

A total of 142 patients (75 males and 67 females) with an average age of 22.72 ± 5.34 years donated autologous blood before their orthognathic surgery. Patients in the transfusion group (n = 56) had significantly lower preoperative red blood cell counts (4.74 ± 0.55 × 109/L versus 4.98 ± 0.45 × 109/L, P = 0.0063), hemoglobin (141.48 ± 15.18 g/dL versus 150.33 ± 14.73 g/dL, P = 0.0008), and hematocrit (41.05% ± 4.03% versus 43.32% ± 3.42%, P = 0.0006), more bimaxillary osteotomies (92.86% versus 56.98%, P < 0.001), longer operation duration (348.4 ± 111.10 minutes versus 261.6 ± 115.44 minutes, P < 0.001), and more intraoperative blood loss (629.23 ± 273.06 ml versus 359.53 ± 222.84 ml, P < 0.001) than their counterparts (n = 86) in the non-transfusion group. Univariable and multivariable logistic regression demonstrated that only hemoglobin (adjusted odds ratio [OR] 0.864, 95% confidence interval [CI]:0.76-0.98, P = 0.026), operation procedures (adjusted OR 8.14, 95% CI:1.69-39.16, P = 0.009), and blood loss (adjusted OR 1.006, 95% CI:1.002-1.009, P < 0.001) were independent risk factors for ATAB. The area under the receiver operating characteristic curve of the nomogram was 0.823. The consistency index of the nomogram was 0.823. The calibration curve illustrated that the nomogram was highly consistent with the actual observation.

CONCLUSIONS

The nomogram is a simple and useful tool with good accuracy and performance in predicting the risk for blood transfusion.

Cell Salvage in Oncological Surgery, Peripartum Haemorrhage and Trauma

Oncological surgery, obstetric haemorrhage and severe trauma are the most challenging conditions for establishing clinical recommendations for the use of cell salvage. When the likelihood of allogeneic transfusion is high, the intraoperative use of this blood-saving technique would be justified, but specific patient selection criteria are needed. The main concerns in the case of oncological surgery are the reinfusion of tumour cells, thereby increasing the risk of metastasis. This threat could be minimized, which may help to rationalize its indication. In severe peripartum haemorrhage, cell salvage has not proven cost-effective, damage control techniques have been developed, and, given the risk of fetomaternal alloimmunization and amniotic fluid embolism, it is increasingly out of use. In trauma, bleeding may originate from multiple sites, coagulopathy may develop, and it should be evaluated whether re-transfusion of autologous blood collected from uncontaminated organ cavities would be feasible. General safety measures include washing recovered blood and its passage through leukocyte depletion filters. To date, no well-defined indications for cell salvage have been established for these pathologies, but with accurate case selection and selective implementation, it could become safe and effective. Randomized clinical trials are urgently needed.

Intraoperative Cell Salvage for Women at High Risk of Postpartum Hemorrhage During Cesarean Section: a Systematic Review and Meta-analysis

Postpartum hemorrhage (PPH) can lead to substantial blood loss that compromises maternal hemodynamic stability and consequently cause severe maternal complications such as organ dysfunction or death. Intraoperative cell salvage (IOCS), an effective method of blood conservation used in other surgical specialties, can be an alternative intervention for managing PPH. Thus, our aim was to evaluate the efficacy and safety of IOCS for women at high risk of PPH undergoing cesarean sections. We conducted a systematic search of electronic databases from inception to February 25, 2021 for randomized controlled studies and observational studies published in English or Mandarin about IOCS use in cesarean sections. Primary outcomes of interest were changes in postoperative hematologic parameters and any adverse events reported among patients that had IOCS and controls that had an allogeneic blood transfusion. The certainty of the evidence of the outcomes was evaluated using the GRADE approach. A total of 24 studies with 5872 patients were included in the meta-analysis. Eleven randomized controlled trials (RCTs), and 13 observational studies were analyzed. Postoperative hemoglobin levels were higher among patients with IOCS SMD 0.39 (95% CI; 0.20, 0.60; P < 0.001, high certainty). Allogeneic blood transfusion increased adverse events RR = 1.81(95% CI; 1.24, 2.62; P = 0.002, low certainty). IOCS shortened hospital stay SMD - 0.59 (95% CI: - 0.98, - 0.19; P = 0.004, low certainty) and shortened prothrombin time SMD - 0.67 (95% CI; - 1.31, - 0.04), P = 0.037, low certainty). The lower incidence of transfusion-related adverse events and shorter hospital stay among other findings demonstrate that IOCS use in obstetrics is an effective and safe alternative for the management of PPH; however, high-quality randomized control studies are required to confirm this evidence.

Obstetrical Hemorrhage

Obstetric hemorrhage is a leading cause of morbidity and mortality. Prevention includes identifying patients with risk factors and actively managing the third stage of labor. The anesthesiologist should be ready to manage hemorrhage with general strategies as well as strategies tailored to the specific cause of hemorrhage. Both neuraxial anesthesia and general anesthesia are appropriate in different situations. Treatments proven to be effective include increasing the oxytocin infusion, administering tranexamic acid early, guiding transfusion with point-of-care tests, and using cell salvage. Utilization of protocols and checklists within systems that encourage effective communication between teams should be implemented.

Plasma rocuronium concentration in cell salvage blood following cardiac surgery: a case series

PURPOSE

The aim of the study was to evaluate the plasma rocuronium concentration in autologous blood transfusion obtained from the cell salvage (CS) system following cardiac surgery with cardiopulmonary bypass (CPB).

METHODS

This prospective observational study was conducted in a university teaching hospital from July to November 2020. Patients undergoing general anesthesia for cardiac surgery with CPB were enrolled in the study. After separation from CPB, residual blood remaining in the extracorporeal system was collected as the control sample. The second sample (CS blood) was collected from the autologous blood transfusion obtained after completion of the CS system with Cell Saver® Elite®. Hematocrit values of both samples were also examined.

RESULTS

Ten subjects (aged 57-86 years) were enrolled in this study. Plasma rocuronium concentrations (ng/ml) were significantly lower in the CS blood (94.0 ± 77.5) compared to the control (2950 ± 812.2) (p = 0.002). Hematocrit values (%) were significantly higher in the CS blood (75.2 ± 11.3) compared to the control (40.2 ± 10.2) (p = 0.002).

CONCLUSION

Autologous blood transfusion obtained from CS system following cardiac surgery with CPB, only retained a small amount of plasma rocuronium concentration, therefore, the risk of autologous blood transfusion contributing to clinically relevant residual neuromuscular blockade postoperatively should be considered to be low.

TRIAL REGISTRATION

This trial was registered in the University Hospital Medical Information Network under registration number UMIN000040877 (registration date; June 24, 2020).

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

Efficacy and cost-effectiveness of cell saver usage in the repair of thoracic aortic aneurysms and dissections

INTRODUCTION

A substantial amount of blood loss occurs during the open repair of aortic aneurysms or dissections. The aim of the present study is to determine the efficacy and cost-effectiveness of cell saver devices in blood conservation during the open repair of thoracic aortic pathologies.

METHODS

The present study prospectively collected the data pertaining to 25 patients who underwent surgical management of thoracic aortic aneurysms or dissections using a cell saver (Group 1, n = 25). The volume and cost of transfusion and postoperative outcomes were compared with the second group of patients who underwent surgery without the use of cell savers in the previous year (Group 2, n = 25); the data pertaining to the same were retrospectively collected from the hospital records. The patient characteristics and categorical variables were compared using the x² test and Fisher's exact test. Transfusion volume and costs were compared using the independent samples t-test and Mann-Whitney U test.

RESULTS

The patients in both the groups displayed similar characteristics and risk factors. The total volume of allogenic red blood cell (p < 0.001) and total blood product (p = 0.01) transfusions were significantly lower in Group 1. The cost of red blood cell (p < 0.001) and total transfusions (p = 0.03) were lower in Group 1. The two groups displayed similar in-hospital morbidity and mortality rates.

CONCLUSIONS

There was a significant association between the use of cell savers and the decreased need for red blood cell and total blood product transfusions. Considering the cost of the cell saver set, transfusion costs in the two groups were comparable.

Intraoperative blood salvage in proximal femur epiphysiolysis surgical treatment with hip controlled dislocation technique: a case series study

Objectives

To report a case series of Intraoperative Blood Salvage (IOS) in surgeries during the treatment for Slipped Capital Femoral Epiphysis (SCFE) with controlled dislocation of the hip, identifying its efficacy, complications, and the profile of patients with SCFE.

Methods

Descriptive study reporting a case series, comprising patients seen between January 2016 and March 2018, diagnosed with SCFE, and treated with controlled surgical dislocation of the hip using IOS.

Results

Sample comprised of 15 patients, with a mean age of 13.1 years. The most affected side was the left with 8 cases. None of the patients required allogeneic blood in the postoperative period. Mean pre- and postoperative hemoglobin were 13.2 and 11.2 g.dL^-1, respectively, and mean hemoglobin difference was 1.8 g.dL^-1. Mean pre- and postoperative hematocrit were 39.13% and 33.20%, respectively, and mean hematocrit difference was 5.52%. No intraoperative complications were observed. One patient presented vomiting and another one, wound infection in the postoperative period.

Conclusion

IOS was an alternative blood salvage approach and prevented allogeneic blood transfusion, enabling reduction of potential complications.

How I treat anemia in the perisurgical setting

Anemia is a common finding in the perioperative setting with significant untoward consequences including worsening of outcomes and diminished quality of life as well as increased risk of allogeneic blood transfusions. Here, we present 3 cases that illustrate how anemia can be perioperatively managed in patients undergoing cardiac, orthopedic, and oncology surgeries. Timely detection of anemia prior to high-blood loss surgeries can allow clinicians to manage it and optimize hemoglobin level, making patients better prepared for the surgery. Treatment of anemia should be guided by the etiology and may include erythropoietic agents, folic acid, B12, and iron preparations. Other blood management strategies geared toward reducing surgical blood loss such as autologous transfusion techniques and agents to optimize hemostasis are used during surgery and in the immediate postoperative period. Patients should be closely monitored following surgery for signs of ongoing bleeding in need of control. Finally, screening for and management of anemia should continue in the postoperative and postdischarge period, as persistence and recurrence of anemia can further undermine patient's outcomes.

Cell saver physics – a review

Cell salvage, cell saver, cell processor or autologous blood transfusion is the process of collecting a patient’s blood from the surgical field, washing, filtering and transfusing it back to the same patient. There are six basic steps involved in cell salvage. Step one involves the collection of shed blood into a reservoir with an anticoagulant-saline mixture. Step two is the filtration of debris and clots. In step three, the red blood cells (RBCs) are separated from the nonerythrocyte components. This process may be likened to clothes in the washing machine. Washing with saline removes contaminants in step four and the RBCs are resuspended in saline and transferred to the reinfusion bag. Waste products are transferred into the waste bag in step five. In step six, the resuspended, washed RBCs are collected in a bag at room temperature which can be reinfused. The functioning of the cell saver is based on Newton’s First and Second Laws of Motion, where centripetal forces are generated to separate the blood components depending on their density. The denser RBCs are driven to the outer wall of the centrifuge bowl with the plasma collecting on the inside. A typical yield will retrieve 50–95.8% RBCs with a final haematocrit of 50–70%. Cell savers are used in procedures with a large volume of anticipated blood loss, high risk of bleeding, low preoperative haemoglobin, in patients with rare blood groups or multiple antibodies and in some Jehovah’s Witness patients.

The Effect of Antifibrinolytic Use on Intraoperative Cell Salvage: Results from a National Registry of Surgical Procedures

Intraoperative cell salvage (ICS) is a critical component of any blood management program involving surgery with a high potential for blood loss. The introduction of antifibrinolytics (AF) may reduce blood loss. The purpose of this study was to evaluate the use of AF on ICS in non-cardiac surgical procedures. Following institutional review board approval, 69,935 consecutive case records between January 2016 and September 2019 from a national registry of adult surgical patients were reviewed. Procedure types were stratified into one of nine surgical categories: general (GN, n = 1,525), neurosurgical (NS, n = 479), obstetric (OB, n = 1,563), cervical spine (CS, n = 2,701), lumbar spine (LS, n = 38,383), hip arthroplasty (HA, n = 13,327), knee arthroplasty (KA, n = 596), vascular (VA, n = 9,845), or orthopedic other (OO, n = 1,516). The primary endpoint was the use of AF with the secondary endpoints ICS shed blood volume and volume available for return. The overall use of AF across all surgical procedures increased from 21.4% in 2016 to 25.4% in 2019. The greatest increases were seen in NS (4.4% to 16.2%), LS (13.7% to 23.1%), and HA (55.8% to 61.9%). For several procedure types, there was an initial increase then either a leveling off or a decline in AF use: OB initially increased from 6.2% to 10.8% in 2018, whereas GN (9.4% to 7.2%) and VA surgery declined slightly (9.9% to 5.7%). When comparing patients who did not receive AF with those who did, there were similar volumes of ICS available for return in all groups, except for LS, GN, and VA, where lower volumes were seen in the No-AF groups. The use of AF has increased each year over the 4-year period in most of the surgical categories, but several have declined. There may be a beneficial effect of AF with lower ICS volumes available for return in a few groups.