Current concepts in the use of cell salvage in obstetrics.

PURPOSE OF REVIEW: The worldwide leading cause of maternal death is severe maternal hemorrhage. Maternal hemorrhage can be profound leading to an entire loss of blood volume. In the past two decades, Patient Blood Management has evolved to improve patient's care and safety. In surgeries with increased blood loss exceeding 500 ml, the use of cell salvage is strongly recommended in order to preserve the patient's own blood volume and to minimize the need for allogeneic red blood cell (RBC) transfusion. In this review, recent evidence and controversies of the use of cell salvage in obstetrics are discussed. RECENT FINDINGS: Numerous medical societies as well as national and international guidelines recommend the use of cell salvage during maternal hemorrhage. SUMMARY: Intraoperative cell salvage is a strategy to maintain the patient's own blood volume and decrease the need for allogeneic RBC transfusion. Historically, cell salvage has been avoided in the obstetric population due to concerns of iatrogenic amniotic fluid embolism (AFE) or induction of maternal alloimmunization. However, no definite case of AFE has been reported so far. Cell salvage is strongly recommended and cost-effective in patients with predictably high rates of blood loss and RBC transfusion, such as women with placenta accreta spectrum disorder. However, in order to ensure sufficient practical experience in a multiprofessional obstetric setting, liberal use of cell salvage appears advisable.

Serious hazards of transfusion: evaluating the dangers of a wrong patient autologous salvaged blood in cardiac surgery.

BACKGROUND: The past half century has seen the near eradication of transfusion-associated hazards. Intraoperative cell salvage while widely used still poses significant risks and hazards due to human error. We report on a case in which blood collected from a patient with lung cancer was mistakenly administered to a patient undergoing cardiac surgery who should have received his own collected blood. The initial investigation found that the cause of the patient harm was violations of procedures by hospital personnel. A detailed investigation revealed that not only violations were the cause, but also that the underlying causes included haphazard organizational policies, poor communication, workload and staffing deficiencies, human factors and cultural challenges. CASE PRESENTATION: On August 14, 2019, a 72-year-old male was admitted to our hospital for angina pectoris and multivessel coronary artery disease. Cardiac surgery was performed using an autologous salvage blood collection system, and there were no major problems other than the prolonged operation time. During the night after the surgery, when the patient's blood pressure dropped, a nurse retrieved a blood bag from the ICU refrigerator that had been collected during the surgery and administered it at the physician's direction, but at this time neither the physician nor the nurse performed the required checking procedures. The blood administered was another patient's blood taken from another surgery the day before; an ABO mismatch transfusion occurred and the patient was diagnosed with DIC. The patient was discharged 65 days later after numerous interventions to support the patient. An accident investigation committee was convened to analyze the root causes and develop countermeasures to prevent a recurrence. CONCLUSION: This adverse event occurred because the protocol for intraoperative blood salvage management was not clearly defined, and the procedure was different from the standard transfusion practices. We developed a new workflow based on a human factors grounded, systems-wide improvement strategy in which intraoperative blood collection would be administered before the patient leaves the operating room to completely prevent recurrence, instead of simply requiring front-line staff to do a double-check. Implementing strong systems processes can reduce the risk of errors, improve the reliability of the work processes and reduce the likelihood of patient harm occurring in the future.

Effectiveness of intraoperative cell salvage combined with a modified leucocyte depletion filter in metastatic spine tumour surgery.

BACKGROUND: To compare the effectiveness of intraoperative cell salvage (IOCS) combined with a modified leucocyte depletion filter (MLDF) with IOCS combined with a regular leucocyte depletion filter (RLDF) in eliminating tumour cells from blood salvage during metastatic spine tumour surgery (MSTS). METHODS: Patients with a known primary epithelial tumour who underwent MSTS were recruited for this study. Blood samples were collected in 5 stages: from the patients' vein before anaesthesia induction (S1), from the operative field at the time of maximum tumour manipulation (S2), and from the operative blood after IOCS processing (S3) and after IOCS+RLDF (S4) and IOCS+MLDF (S5) processing. The polyploids of tumour cells in the blood samples were collected and counted with immunomagnetic separation enrichment and fluorescence in situ hybridization. RESULTS: We recruited 20 patients. Tumour cells were detected in 14 patients (70%) in S1, 16 patients (80%) in S2, 13 patients (65%) in S3, and 12 patients (60%) in S4. MLDF was added in 8 patients. Tumour cells were detected in only 1 of 8 patients in S5 (12.5%). There were significantly fewer tumour cells in the samples collected after MLDF processing (S5) than in the samples collected after RLDF (S4) and around the tumour (S2) (P = 0.016 and P = 0.039, respectively). Although no significant difference was observed between S4 and S1, a downward trend was observed after IOCS+RLDF processing. CONCLUSIONS: Tumour cells could be removed by IOCS combined with RLDF from blood salvaged during MSTS, but residual tumour cells remained. The findings support the notion that MLDF eliminates tumour cells more effectively than RLDF. Hence, this technique can be applied to MSTS. TRIAL REGISTRATION: ChiCTR1800016162 Chinese Clinical Trial Registry.

The safty profile of blood salvage applied for collected blood with amniotic fluid during cesarean section.

BACKGROUND: The guidelines of National Health Service(NHS, the United Kingdom) recommended for use in obstetrics at increased risk of bleeding, requiring two suction devices to reduce amniotic fluid contamination, however, when comes to massive hemorrhage, it is may difficult to operate because the complex operation may delay time. The aim of the study was to detect the effect of amniotic fluid recovery on intraoperative cell salvage in obstetrics and provide evidence for clinical applications. METHOD: Thirty-four patients undergoing elective cesarean section were randomly divided into two groups. In group 1, the cumulative blood from the operation field, including the amniotic fluid, was collected using a single suction device for processing. In group 2, after suctioning away the amniotic fluid using another suction device for the cumulative blood from the operation field. From each group, four samples were taken, including maternal venous blood (sample I), blood before washing (sample II), blood after washing (sample III) and blood after filtration with a leukocyte filter (sample IV), to detect serum potassium (K +), hemoglobin (Hb), white blood cell (WBC), fetal hemoglobin (HbF), alpha fetoprotein (AFP) and squamous cell (SC) levels. RESULTS: The AFP, K + and WBC levels of sample III and sample IV were significantly lower than sample I in group 1 and group 2 (P < 0.05). Significantly more SCs were found in sample III than in sample I in group 1 and group 2 (P < 0.05), but SCs of sample IV had no statistical difference compared to sample I in group 1 and group 2 (P > 0.05). There was no significant difference in the K + , Hb, WBC, AFP and SC levels of sample IV between group 1 and group 2 (P > 0.05). The HbF levels of sample III and sample IV were significantly higher in group 1 than in group 2 (P < 0.05). CONCLUSION: There is little or no possibility for AF contamination to enter the re-infusion system when used in conjunction with a leucodepletion filter. For maternal with Rh-negative blood, we recommend two suction devices to reduce HbF pollution. TRIAL REGISTRATION: ChiCTR1800015684 , 2018.4.15.

Removal of EpCAM-positive tumor cells from blood collected during major oncological surgery using the Catuvab device- a pilot study.

BACKGROUND: Intraoperative blood salvage (IBS) is regarded as an alternative to allogeneic blood transfusion excluding the risks associated with allogeneic blood. Currently, IBS is generally avoided in tumor surgeries due to concern for potential metastasis caused by residual tumor cells in the erythrocyte concentrate. METHODS: The feasibility, efficacy and safety aspects of the new developed Catuvab procedure using the bispecific trifunctional antibody Catumaxomab was investigated in an ex-vivo pilot study in order to remove residual EpCAM positive tumor cells from the autologous erythrocyte concentrates (EC) from various cancer patients, generated by a IBS device. RESULTS: Tumor cells in intraoperative blood were detected in 10 of 16 patient samples in the range of 69-2.6 × 105 but no residual malignant cells in the final erythrocyte concentrates after Catuvab procedure. IL-6 and IL-8 as pro-inflammatory cytokines released during surgery, were lowered in mean 28-fold and 52-fold during the Catuvab procedure, respectively, whereas Catumaxomab antibody was detected in 8 of 16 of the final EC products at a considerable decreased and uncritical residual amount (37 ng in mean). CONCLUSION: The preliminary study results indicate efficacy and feasibility of the new medical device Catuvab allowing potentially the reinfusion of autologous erythrocyte concentrates (EC) produced by IBS device during oncological high blood loss surgery. An open-label, multicenter clinical study on the removal of EpCAM-positive tumor cells from blood collected during tumor surgery using the Catuvab device is initiated to validate these encouraging results.

Does tourniquet use decrease blood loss following primary total knee arthroplasty in Jehovah's Witness patients?

OBJECTIVES: This study aims to investigate the use of multiple blood management strategies and the effect of tourniquet on the estimated blood loss (EBL) in Jehovah's Witness (JW) patients who underwent primary total knee arthroplasty (TKA). PATIENTS AND METHODS: Twenty-two self-reported JW patients (9 males, 13 females; mean age 66.8±8.6 years; range, 51 to 83 years) who underwent primary TKA between January 2014 and January 2020 in our institution were retrospectively reviewed. A standard blood management protocol that consisted of hypotensive anesthesia, local and systemic administration of tranexamic acid (TXA) and intraoperative cell salvage was applied to all patients. Patients were divided into two groups: with (n=11) and without (n=11) tourniquet use. The EBL was calculated according to Meunier's formula. Hemoglobin (Hgb), hematocrit (Hct), and EBL on the first and third postoperative days were compared statistically. RESULTS: There was no significant difference between groups regarding postoperative Hgb (p=0.801 and p=0.767), Hct (p=0.617 and p=0.895), Hgb decline (p=0.311 and p=0.822), and EBL (p=0.067 and p=0.284) at first and third postoperative days. None of the patients required blood transfusion. No wound complication or symptomatic deep vein thrombosis was seen during the hospital stay. CONCLUSION: Combined use of hypotensive anesthesia, intravenous administration of TXA, intraoperative periarticular injection, and cell salvage seem to be sufficient in controlling the blood loss in JW patients during TKA. Additional tourniquet use may not further decrease the EBL.

[Blood-saving technologies in extensive liver resections]. / Taktika krovosberezheniya pri obshirnykh rezektsiyakh pecheni.

The researches devoted to blood-saving technologies in extensive liver resections are analyzed in the manuscript. Resection of three and more liver segments is effective method of surgical treatment of various focal liver lesions. Surgical (anatomical resection with hilar glissonean access, Pringle maneuver, modern technical equipment, etc.), anesthesiological (reduction of central venous pressure, hemostatic agents) and transfusion (autologous blood donation, transfusion, cell saver, etc.) methods contribute to prevention and reduction of blood loss. Intraoperative measures for blood loss prevention should include adequate surgical incision and liver mobilization, precise techniques of parenchymal dissection (for example, cavitation surgical aspirator-destructor), use of clip applicators and local or systemic hemostatic agents.

[Safety of cell salvage in tumor surgery : Systematic review with meta-analysis]. / Sicherheit der maschinellen Autotransfusion in der Tumorchirurgie : Systematisches Review mit Metaanalyse.

BACKGROUND: Allogeneic blood transfusion is avoidable in many oncological interventions by the use of cell salvage or mechanical autotransfusion (MAT). As irradiation is elaborate and expensive, the safety of leucocyte depletion filters (LDF) for autologous blood from the surgical field might be a more acceptable alternative for the prevention of cancer recurrences. A previous meta-analysis could not identify an increased risk of cancer recurrence. The aim of this review article is to provide an update of a previous meta-analysis from 2012 as well as a safety analysis of cell salvage with LDF due to the improved data situation. MATERIAL AND METHODS: This systematic review included all studies in PubMed, Cochrane, Cochrane Reviews and Web of Science on cell salvage or autotransfusion combined with outcomes, e.g. cancer recurrence, mortality, survival, blood transfusion, length of hospital stay (LOS) after the use of MAT without irradiation and with or without LDF. The grades of recommendations (GRADE) assessment of underlying evidence was applied. RESULTS: A total of seven new observational studies and seven meta-analyses were found that compared unfiltered or filtered cell salvage with autologous predeposition, allogeneic transfusion or without any transfusion. No randomized controlled trials have been completed. A total of 27 observational and cohort studies were included in a meta-analysis. The evidence level was low. The risk of cancer recurrence in recipients of autologous salvaged blood with or without LDF was reduced (odds ratio, OR 0.71, 95% confidence interval, CI 0.58-0.86) as compared to non-transfused subjects, allogeneic or predeposited autologous transfusion. The transfusion rate could not be assessed due to the substantial selection bias and large heterogeneity. Cell salvage does not change mortality and LOS. Leucocyte depletion studies reported a removal rate of cancer cells in the range of 99.6-99.9%. CONCLUSION: Randomized controlled trials on a comparison of MAT and allogeneic blood transfusion as well as LDF and irradiation would be desirable but are not available. From observational trials and more than 6300 subjects and various tumors, cell salvage in cancer surgery with or without LDF appears to be sufficiently safe. The efficacy of leucocyte depletion of autologous salvaged blood is equivalent to irradiation. Unavailability of radiation is not a contraindication for cell salvage use in cancer surgery. By usage of leucocyte depleted salvaged autologous blood, the risks of allogeneic transfusion can be avoided.

The role of intra-operative cell salvage in patient blood management for revision hip arthroplasty: a prospective cohort study.

Cell salvage is an important component of blood management in patients undergoing revision hip arthroplasty surgery. However concerns regarding efficacy and patient selection remain. The aims of this study were to describe intra-operative blood loss, cell salvage re-infusion volumes and red blood cell transfusion rates for revision hip procedures and to identify factors associated with the ability to salvage sufficient blood intra-operatively to permit processing and re-infusion. Data were collected from a prospective cohort of 664 consecutive patients undergoing revision hip surgery at a single tertiary centre from 31 March 2015 to 1 April 2018. Indications for revision surgery were aseptic (n = 393 (59%)) fracture (n = 160 (24%)) and infection (n = 111 (17%)). Salvaged blood was processed and re-infused when blood loss exceeded 500 ml. Mean (SD) intra-operative blood loss was 1038 (778) ml across all procedures. Salvaged blood was re-infused in 505 of 664 (76%) patients. Mean (SD) re-infusion volume was 253 (169) ml. In total, 246 of 664 (37%) patients received an allogeneic red blood cell transfusion within 72 h of surgery. Patients undergoing femoral component revision only (OR (95%CI) 0.41 (0.23-0.73)) or acetabular component revision only (0.53 (0.32-0.87)) were less likely to generate sufficient blood salvage volume for re-infusion compared with revision of both components. Compared with aseptic indications, patients undergoing revision surgery for infection (1.87 (1.04-3.36)) or fracture (4.43 (2.30-8.55)) were more likely to generate sufficient blood salvage volume for re-infusion. Our data suggest that cell salvage is efficacious in this population. Cases where the indication is infection or fracture and where both femoral and acetabular components are to be revised should be prioritised.

Impact of Intraoperative Cell Salvage on Blood Coagulation Factor Concentrations in Patients Undergoing Cardiac Surgery.

BACKGROUND: Cardiothoracic surgery is associated with major blood loss and allogeneic transfusion of red blood cell concentrates. To minimize allogeneic red blood cell (RBC) transfusion, intraoperative cell salvage has been effectively used for years. The objective of this study was to evaluate the impact of cell salvage on blood coagulation factors. METHODS: We enrolled 30 patients scheduled for cardiac surgery in a prospective single-center observational cohort study at an academic hospital. Blood samples from the cell salvage system were obtained from both the reservoir and the processed red blood cell concentrate. Coagulation factors, fibrinogen, antithrombin and von Willebrand activity, and antigen were assessed before and after cell salvage. Statistical analysis was performed using Wilcoxon matched-pairs signed rank test. RESULTS: Our results revealed a significant decrease of fibrinogen (P < .001), coagulation factors II (P = .004), factors VII, X, and XIII (P < .001), and all other measured coagulation factor concentrations/activities in the processed red blood cell concentrate, when compared to the concentrations/activities of the reservoir. CONCLUSIONS: The results of the present study revealed a significant reduction of coagulation factor concentrations/activities by the washing process. Therefore, physicians need to consider adequate management of coagulation in patients with major blood loss and the need of large volumes of RBC transfusion.

Intraoperative cell salvage as part of a blood conservation strategy in an obstetric population with abnormal placentation at a large Irish tertiary referral centre: an observational study.

BACKGROUND: Haemorrhagic morbidity is more common in women with abnormal placentation, that is placenta praevia or morbidly adherent placenta. The incidence of abnormal placentation is increasing due to rising caesarean section rates. Concerns regarding blood safety, blood shortages and soaring costs of blood processing have generated growing enthusiasm for blood conservation strategies. The aim of our study was to look at intraoperative cell salvage (IOCS) use and allogeneic transfusion patterns in patients with abnormal placentation. METHODS: Patients with abnormal placentation were identified from the hospital database over a 2-year period between 2015 and 2016. Information collected for those that had IOCS setup included estimated blood loss, volume of blood collected and returned, pre- and postoperative haemoglobin levels and use of allogeneic blood. RESULTS: A total of 139 cases of abnormal placentation were identified. Abnormal placentation accounted for 62% of all cases of IOCS usage and was established for 53 patients with abnormal placentation. The re-transfusion rate was 18.5%. Five patients received IOCS blood only. The allogeneic transfusion rate was 7.5% in patients who had IOCS setup compared with 6.9% in those who did not (p = 1.00). Median blood loss was greater for patients who had IOCS blood returned compared with patients who had not (p = 0.004). The median volume of blood returned was 520 (114-608) mL. Preoperative haemoglobin levels were lower for patients who received a combination of cell salvage and allogeneic blood (p = 0.006). CONCLUSIONS: IOCS contributed to a reduction or elimination of allogeneic transfusion for a proportion of this high-risk cohort and should be an integral component of a hospitals' blood conservation strategy.

Efficiency of leukocyte depletion filters and micro-aggregate filters following intra-operative cell salvage during cesarean delivery.

BACKGROUND: Intra-operative cell salvage is not routinely used during cesarean delivery because it is not cost-effective for patients at low risk of hemorrhage and there are theoretical concerns about amniotic fluid embolism. Some guidelines recommend using leukocyte depletion filters to decrease the risk of amniotic fluid embolism before re-infusing salvaged blood, but these filters are not available in Japan. We compared the efficacy and safety of leukocyte depletion and micro-aggregate filters in combination with intra-operative cell salvage during cesarean delivery. METHODS: Blood was collected in a Cell Saver 5 reservoir during cesarean delivery. Four samples were collected: pre-wash, post-wash, post-filtration with a leukocyte depletion filter and post-filtration with a micro-aggregate filter. Each sample was analyzed for amniotic fluid markers of zinc coproporphyrin-1 and sialyl-Tn, for fetal hemoglobin, and the sample underwent pathological examination for white blood cells and squamous cells. Post-filtration samples were compared using paired t-tests with P <0.05 indicating statistical significance. RESULTS: Zinc coproporphyrin-1 and sialyl-Tn were negative at almost all sample points. Squamous cells decreased by 59.1% post-wash and 91.2% post-filtration using a leukocyte depletion filter. Leukocyte depletion filters removed 99.7% of white blood cells and were more effective in removing white blood cells than micro-aggregate filters (P=0.02). CONCLUSION: Leucocyte depletion filters are more effective in removing white blood cells and squamous cells than micro-aggregate filters, and their introduction for intra-operative cell salvage during cesarean delivery should be considered in Japanese clinical practice.

Postoperative Blood Salvage and Autotransfusion for Adult Spinal Deformity: A Randomized Controlled Trial.

STUDY DESIGN: Randomized controlled trial. OBJECTIVE: The aim of this study was to determine whether postoperative blood salvage and autotransfusion versus traditional closed suction drainage reduces the rate of homologous blood transfusions in patients undergoing surgery for adult spinal deformity. SUMMARY OF BACKGROUND DATA: The use of intraoperative blood salvage has become commonplace in spine surgery; however, the collection and reinfusion of blood drained from the wound postoperatively have not been employed routinely because of increased cost and questionable benefit. METHODS: Adult patients undergoing long posterior fusions were randomized to either a blood salvage and reinfusion system (OrthoPat - Group 1) or a standard subfascial closed suction drain (Group 2). Blood collected in Group 1 was reinfused according to the manufacturer's protocol. Reinfusion drains were converted to standard closed suction drains when output was <50 mL during 4 hours, and drains were removed when output was minimal. Patients received autologous or homologous blood transfusions when hemoglobin (Hg) <8 g/dL or they had symptomatic anemia. RESULTS: Thirty-four patients were randomized into Group 1 and 36 patients into Group 2. There were no differences in preoperative or intraoperative parameters. Patients in Group 1 had higher hemoglobin levels on postoperative day (POD) 2 and POD 3 compared to those in Group 2. However, there was no significant difference in the percentage of patients requiring homologous blood transfusion between the two groups (41% Group 1 vs. 60% Group 2, P = 0.17). Similarly a subgroup analysis in patients with estimated blood loss >2000 mL also showed no difference in homologous blood transfusion rates (67% Group 1 vs. 76% Group 2, P = 0.58). There were no differences in the rate or type of postoperative complications. CONCLUSION: Postoperative blood salvage and reinfusion result in a higher hemoglobin level in the early postoperative period, but does not significantly reduce the need for homologous blood transfusion. LEVEL OF EVIDENCE: 1.

How do I perform cell salvage in obstetrics?

Maternal mortality in the United States is increasing. The leading cause of death is hemorrhage. Maternal hemorrhage can be profound, with entire blood volumes being lost. In most major blood loss surgery, autotranfusion (also known as cell salvage, cell saving, and intraoperative blood collection and readministration) is a technique that has been used to minimize allogeneic transfusion. Historically, autotransfusion has been considered contraindicated in the face of maternal hemorrhage because of a fear of incorporating amniotic fluid in the salvaged blood. Recent data suggests that this fear is unfounded, with several medical societies now recommending that autotransfusion be used during maternal hemorrhage. In this review, autotransfusion during maternal hemorrhage is discussed, and suggestions are made for how to make it most successful.

Hemolytic reaction in the washed salvaged blood of a patient with paroxysmal nocturnal hemoglobinuria.

BACKGROUND: In patients with paroxysmal nocturnal hemoglobinuria (PNH), the membrane-attack complex (MAC) formed on red blood cells (RBCs) causes hemolysis due to the patient's own activated complement system by an infection, inflammation, or surgical stress. The efficacy of transfusion therapy for patients with PNH has been documented, but no studies have focused on the perioperative use of salvaged autologous blood in patients with PNH. CASE PRESENTATION: A 71-year-old man underwent total hip replacement surgery. An autologous blood salvage device was put in place due to the large bleeding volume and the existence of an irregular antibody. The potassium concentration in the transfer bag of salvaged RBCs after the wash process was high at 6.2 mmol/L, although the washing generally removes > 90% of the potassium from the blood. This may have been caused by continued hemolysis even after the wash process. Once activated, the complement in patients with PNH forms the MAC on the RBCs, and the hemolytic reaction may not be stopped even with RBC washing. CONCLUSIONS: Packed RBCs, instead of salvaged autologous RBCs, should be used for transfusions in patients with PNH. The use of salvaged autologous RBCs in patients with PNH should be limited to critical situations, such as massive bleeding. Physicians should note that the hemolytic reaction may be present inside the transfer bag even after the wash process.

Safety and efficacy of a simple cardiotomy suction system as a blood salvage procedure during off-pump coronary artery bypass surgery.

The ideal blood-salvaging strategies for off-pump coronary artery bypass graft procedures have not been determined. We developed a new blood-salvaging system that uses a cardiotomy suction. The purpose of this study was to examine the efficacy of this novel method. This was a retrospective study involving 50 consecutive patients undergoing off-pump coronary artery bypass grafting. In 25 patients, a simple cardiotomy suction system was used (cardiotomy suction group). These individuals were compared with 25 historical cohorts who were treating with the conventional cell saver system (cell saver group). There was no in-hospital mortality in either group. In the cell saver group, there was one major complication (stroke) and two minor complications (saphenous vein graft occlusion, superficial wound infection). In the cardiotomy suction group, there was one minor complication (subclinical pulmonary emboli). The cardiotomy suction group received significantly fewer transfused RBC (cardiotomy: 0.56 ± 1.4 units vs. cell saver: 2.46 ± 3.3 units, p = 0.005). The serum total protein and albumin levels were significantly higher in the cardiotomy group. Our newly developed simple cardiotomy suction system, when compared with the conventional cell saver system, produced similar clinical results and attenuated postoperative hemodilution. Our system may emerge as a preferable alternative for blood salvage during off-pump coronary artery bypass grafting.

Red blood cells are damaged by intraoperative blood salvage via Ca2+-dependent and -independent mechanisms.

AIMS: Intraoperative blood salvage (IBS) is associated with shortened lifespan of red blood cells (RBCs). This study aims to examine how salvaged RBCs are compromised during IBS. MAIN METHODS: Thirty patients who underwent vertebra surgery with IBS were included in the study. To examine possible mechanisms of IBS-induced injury, both fresh and salvaged RBCs from each patient were mixed with plasma, the Ca2+ ionophore ionomycin or mannitol-adenine-phosphate (MAP) solution (n = 10 patients per condition). Binding of Fluo-3 and/or Annexin V by RBCs was measured. KEY FINDINGS: The percentage of Fluo-3-binding RBCs in salvaged samples was 2.83 ±â€¯0.76%, which increased to 15.34 ±â€¯5.99% after 48-h incubation in plasma. These percentages were significantly higher than those observed with fresh RBCs (P < 0.01). Ionomycin dose-dependently increased the percentage of Fluo-3-binding RBCs in salvaged samples, while MAP solution decreased it. Incubating salvaged RBCs in plasma for 48 h increased the percentage of Fluo-3-positive spherocytes from 0.8 ±â€¯0.6% to 11.35 ±â€¯3.96%, and this increase was blocked by MAP solution. Ionomycin increased the percentage of RBCs binding both Fluo-3 and Annexin V, while MAP decreased this percentage. The percentage of Annexin V-binding RBCs was also higher in salvaged samples than in fresh samples, but this percentage was unaffected by either ionomycin or MAP solution. SIGNIFICANCE: Our results suggest that IBS induces a postponed RBC damage by inducing spherocyte formation, which likely reflects Ca2+ entry induced by energy exhaustion, as well as by exposing phosphatidylserine on the RBC surface, which likely occurs via Ca2+ entry and via Ca2+-independent pathways.

Impact of intraoperative high-volume autologous blood collection on allogeneic transfusion during and after cardiac surgery: a propensity score matched analysis.

BACKGROUND: Perioperative use of allogeneic blood products is associated with higher morbidity, mortality, and hospital costs after cardiac surgery. Blood conservation techniques such as acute normovolemic hemodilution (ANH) report variable success. We hypothesized that large-volume ANH with limited hemodilution would reduce allogeneic blood transfusion compared to the standard practice. STUDY DESIGN AND METHODS: Retrospective observational study of cardiac surgery patients at the University of Maryland Medical Center between January 2014 and September 2017. Using the institutional Society of Thoracic Surgeons database 91 autologous and 981 control patients who underwent coronary artery bypass grafting, aortic valve replacement, or both were identified. After propensity matching of 13 preoperative characteristics, 84 autologous and 84 control patients were evaluated. Our primary endpoint was avoidance of blood transfusion during index hospitalization, and secondary endpoints were postoperative bleeding and major adverse outcomes. RESULTS: The median harvest volumes in the ANH and control groups were 1100 mL and 400 mL, respectively. Of the ANH group, 25% received any transfusion versus 45.2% of the control group after propensity score matching (p < 0.006). When controlling for preoperative platelet count, the transfusion rate ratios for ANH were 0.58 (95% confidence interval, 0.39-0.88) for RBCs and 0.63 (0.44-0.89) for non-RBC components, which were both found to be statistically significant. There was no difference found in major adverse events. CONCLUSION: These results suggest that large-volume ANH is beneficial in reducing both RBC and non-RBC component usage in cardiac surgery. A further prospective validation is warranted.

Cost-effectiveness of cell salvage and donor blood transfusion during caesarean section: results from a randomised controlled trial.

OBJECTIVES: To evaluate the cost-effectiveness of routine use of cell salvage during caesarean section in mothers at risk of haemorrhage compared with current standard of care. DESIGN: Model-based cost-effectiveness evaluation alongside a multicentre randomised controlled trial. Three main analyses were carried out on the trial data: (1) based on the intention-to-treat principle; (2) based on the per-protocol principle; (3) only participants who underwent an emergency caesarean section. SETTING: 26 obstetric units in the UK. PARTICIPANTS: 3028 women at risk of haemorrhage recruited between June 2013 and April 2016. INTERVENTIONS: Cell salvage (intervention) versus routine care without salvage (control). PRIMARY OUTCOME MEASURES: Cost-effectiveness based on incremental cost per donor blood transfusion avoided. RESULTS: In the intention-to-treat analysis, the mean difference in total costs between cell salvage and standard care was £83. The estimated incremental cost-effectiveness ratio (ICER) was £8110 per donor blood transfusion avoided. For the per-protocol analysis, the mean difference in total costs was £92 and the ICER was £8252. In the emergency caesarean section analysis, the mean difference in total costs was £55 and the ICER was £13 713 per donor blood transfusion avoided. This ICER is driven by the increased probability that these patients would require a higher level of postoperative care and additional surgeries. The results of these analyses were shown to be robust for the majority of deterministic sensitivity analyses. CONCLUSIONS: The results of the economic evaluation suggest that while routine cell salvage is a marginally more effective strategy than standard care in avoiding a donor blood transfusion, there is uncertainty in relation to whether it is a less or more costly strategy. The lack of long-term data on the health and quality of life of patients in both arms of the trial means that further research is needed to fully understand the cost implications of both strategies. TRIAL REGISTRATION NUMBER: ISRCTN66118656.