Efficacy of intraoperative cell salvage in spine surgery: a meta-analysis
J Neurosurg Spine. 2020;:1-9
OBJECTIVE Intraoperative cell salvage systems, or cell savers, are widely used for the management of blood loss in patients undergoing spine surgery. However, recent studies report conflicting evidence of their efficacy. The purpose of the meta-analysis was to investigate the efficacy of cell savers in reducing blood transfusion requirements in patients undergoing spine surgery. METHODS Both retrospective and prospective studies that investigated the efficacy of cell savers in reducing transfusion requirements in spine surgery patients when compared with control patients were identified from MEDLINE, Embase, Cochrane Collaboration Library, Google Scholar, and Scopus databases. Outcome data extracted included number of patients receiving allogenic transfusions (transfusion rate); units of allogenic transfusions; postoperative hemoglobin; costs; operative time; and complications. RevMan 5 software was used to perform statistical analyses. A random-effects model was used to calculate pooled odds ratios (with 95% CIs) and weighted mean differences (WMDs [95% CI]) for dichotomous and continuous variables, respectively. RESULTS Eighteen studies with 2815 patients in total were included in the meta-analysis. During spine surgery, the use of intraoperative cell salvage did not reduce the intraoperative (OR 0.66 [95% CI 0.30, 1.41]), postoperative (OR -0.57 [95% CI 0.20, 1.59]), or total transfusion (OR 0.92 [95% CI 0.43, 1.98]) rate. There was a reduction in the number of allogenic units transfused intraoperatively by a mean of 0.81 (95% CI -1.15, -0.48). However, there were no differences in the number of units transfused postoperatively (WMD -0.02 [95% CI -0.41, 0.38]) or the total units transfused (WMD 0.08 [95% CI -1.06, 1.22]). There were also no differences in operative time (WMD 19.36 [95% CI -2.43, 42.15]) or complications reported (OR 0.79 [95% CI 0.46, 1.37]) between groups. A difference in postoperative hemoglobin (WMD 0.54 [95% CI 0.11, 0.98]) between both groups was observed. CONCLUSIONS Cell saver is efficacious at reducing intraoperative allogenic units transfused. There is no difference in transfusion rates, postoperative units transfused, and the total number of units transfused. Further cost analysis studies are necessary to evaluate the cost-effectiveness of this method of blood conservation. CLASSIFICATION OF EVIDENCE Type of question: therapeutic; study design: meta-analysis; strength of recommendation: low.
Patients undergoing spine surgery (18 studies, n=2815).
Use of intraoperative cell salvage.
The use of intraoperative cell salvage did not reduce the intraoperative, or total transfusion rate. There was a reduction in the number of allogenic units transfused intraoperatively by a mean of 0.81. However, there were no differences in the number of units transfused postoperatively or the total units transfused. There were also no differences in operative time or complications reported between groups. A difference in postoperative hemoglobin between both groups was observed.
Post-Operative Blood Salvage and Autotransfusion for Adult Spinal Deformity: A Randomized Controlled Trial
STUDY DESIGN Randomized controlled trial. OBJECTIVE To determine whether post-operative blood salvage and autotransfusion vs. 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 intra-operative blood salvage has become commonplace in spine surgery; however, the collection and reinfusion of blood drained from the wound post-operatively has not been employed routinely due to 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 less than 50cc over 4 hours, and drains were removed when output was minimal. Patients received autologous or homologous blood transfusions when Hg < 8 g/dL or they had symptomatic anemia. RESULTS 34 patients were randomized into Group 1 and 36 patients into Group 2. There were no differences in pre-operative or intra-operative parameters. Patients in Group 1 had higher hemoglobin levels on 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 EBL > 2000cc 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 post-operative complications. CONCLUSIONS Post-operative blood salvage and reinfusion results in a higher hemoglobin level in the early post-operative period, but does not significantly reduce the need for homologous blood transfusion. LEVEL OF EVIDENCE 1.
The effects of leukocyte filtration on cell salvaged autologous blood transfusion on lung function and lung inflammatory and oxidative stress reactions in elderly patients undergoing lumbar spinal surgery
Journal of Neurosurgical Anesthesiology. 2018;31((1):):36-42
BACKGROUND This study was designed to investigate the effects of leukocyte filtration of autologous salvaged blood on lung function, lung inflammatory reaction, and oxidative stress reaction in elderly patients undergoing lumbar spinal surgery. MATERIALS AND METHODS Sixty elderly patients undergoing lumbar spinal surgery were randomly divided into 2 groups: Leukocyte Filter group and Control group. Serum levels of inflammatory markers including white blood cell and polymorphonuclear count, neutrophil elastase, serum surfactant protein A, methane dicarboxylic aldehyde, superoxide dismutase, interleukin (IL)-6, IL-8, tumor necrosis factor-alpha, and respiratory function markers including dynamic respiratory system compliance, oxygenation index, and respiratory index were measured immediately before induction of anesthesia (T0), immediately before blood transfusion (T1), and 1 (T2), 6 (T3), and 12 hours (T4) after end of blood transfusion. RESULTS The Leukocyte Filter group had higher dynamic respiratory system compliance at T2, oxygenation index at T2 and T3, respiratory index and superoxide dismutase at T2, T3, and T4 than those in the Control group (P<0.05). The Leukocyte Filter group had lower white blood cell, polymorphonuclear count, neutrophil elastase, serum surfactant protein A, methane dicarboxylic aldehyde, IL-6, IL-8, and tumor necrosis factor-alpha at T2, T3, and T4 than those in the Control group (P<0.05). There were no significant differences in adverse reactions related specifically to blood transfusion or postoperative respiratory complications within 72 hours. CONCLUSIONS Salvaged autologous blood leukocyte filtration can improve ventilation, promote gas exchange and oxygenation, and inhibit lung inflammatory and oxidative stress reactions in elderly patients undergoing lumbar spinal surgery.
Randomized trial of Cell Saver in 2- to 3-level lumbar instrumented posterior fusions
Journal of Neurosurgery. Spine. 2018;:1-6.
OBJECTIVE The goal of this study was to determine efficacy and cost-effectiveness of Cell Saver in 2- and 3-level lumbar decompression and fusion. METHODS Patients seen at a tertiary care spine center who were undergoing a posterior 2- or 3-level lumbar decompression and fusion were randomized to have Cell Saver used during their surgery (CS group, n = 48) or not used (No Cell Saver [NCS] group, n = 47). Data regarding preoperative and postoperative hemoglobin and hematocrit, estimated blood loss, volume of Cell Saver blood reinfused, number of units and volume of allogeneic blood transfused intraoperatively and postoperatively, complications, and costs were collected. Costs associated with Cell Saver use were calculated based on units of allogeneic blood transfusions averted. RESULTS Demographics and surgical parameters were similar in both groups. The mean estimated blood loss was similar in both groups: 612 ml in the CS group and 742 ml in the NCS group. There were 53 U of allogeneic blood transfused in 29 patients in the NCS group at a total blood product cost of $67,688; and 38 U of allogeneic blood transfused in 16 patients in the CS group at a total blood cost of $113,162, resulting in a cost of $3031 per allogeneic blood transfusion averted using Cell Saver. CONCLUSIONS Cell Saver use produced lower rates of allogeneic transfusion but was found to be more expensive than using only allogeneic blood for 2- and 3-level lumbar degenerative fusions. This increased cost may be reasonable to patients who perceive that the risks associated with allogeneic transfusions are unacceptable. CLASSIFICATION OF EVIDENCE Type of question: therapeutic; study design: randomized controlled trial; evidence: class III.
Evaluation of acute normovolemic hemodilution in patients undergoing intracranial meningioma resection: a quasi-experimental trial
The aim of this study was to evaluate the safety of acute normovolemic hemodilution (ANH) for patients undergoing intracranial meningioma resection.Eighty patients (aged 48-65 years) with American Society of Anesthesiologists physical status I-II undergoing intracranial meningioma resection were included in this prospective observational study. The patients were randomly divided into group A (ANH group), which underwent a combination of ANH and intraoperative cell salvage (ICS), and group B (control group), which underwent ICS alone. The study parameters were recorded as baseline values before blood drainage (T0), after blood drainage (T1), and before (T2) and after (T3) retransfusion in group A. Whereas in group B, the same parameters were measured 10 minutes after anesthesia induction (T0), before surgery (T1), and before (T2) and after (T3) transfusion of autologous blood.When intraoperative blood loss was <2000 mL, the mean volume of homologous blood transfused in group A patients was 100.8 +/- 82.3 mL, compared with the 190.0 +/- 91.8 mL in group B. Reduction in homologous blood used in group A was statistically significant (P < .05). In group B, 15.1% patients received homologous blood, whereas only 5.9% patients received homologous blood in group A. The difference in heart rate between both groups at different time points was statistically nonsignificant (P > .05). The mean hemoglobin and hematocrit levels at T1 and T2 in group A were lower than in group B (P < .05). The prothrombin time and activated partial thromboplastin time in both groups were prolonged significantly after T2 (all P < .05), but were all within normal range. There were no significant differences in postoperative hospital stay, mortality, and postoperative infection between the 2 groups.For patients undergoing excision of intracranial meningioma, ANH is an effective procedure to reduce the need for allogeneic transfusions.
Cell salvage used in scoliosis surgery: is it really effective?
World Neurosurgery. 2017;101:568-576
BACKGROUND Scoliosis surgery is usually associated with large volume of intraoperative blood loss and cell salvage is commonly used to filter and retranfusion autologous blood to patients. However, the efficacy of using cell salvage in scoliosis surgery is still controversial. OBJECTIVE The purpose of this study is to make clear that intraoperative use of cell salvage is effective to decrease the volume of perioperative allogenic blood transfusion in scoliosis surgery. METHOD A meta-analysis was conducted to identify the relevant studies from PubMed, EMbase, Medline, Cochrane library and Google scholar till July 2016. All randomized trials and controlled clinical studies comparing the clinical outcomes of using cell salvage versus noncell salvage in scoliosis surgery were retrieved for the meta-analysis. The data were analyzed by RevMan 5.3. RESULTS A total of 7 studies with 562 patients were included in this meta-analysis. Based on the analysis, the volumes of perioperative and postoperative allogenic RBCs transfusion in cell salvage group were significantly less than those in control group (P = 0.04 and P = 0.01). However, no significant difference was detected in the amount of intraoperative allogenic RBCs transfusion and the risk of patients needing allogenic blood transfusion between the two groups (P = 0.14 and P = 0.61). Both the hemoglobin and hematocrit levels on the first day after surgery were significantly higher in cell salvage group than those in control group (P = 0.002 and P < 0.001). But no significant differences were noted in neither hemoglobin nor hematocirt level at the time of discharge between the two groups (P = 0.76 and P = 0.32). One of the included study reported the number of patients with complications related to transfusion in the two groups, which was not significant different (P = 0.507). CONCLUSIONS Cell salvage significantly reduced the volumes of perioperative and postoperative allogenic RBCs transfusion in scoliosis surgery and increased the hemoglobin and hematocrit levels on the first day postoperatively. In addition, it seemed not increase the rate of transfusion complications during the surgery.
Vancomycin added to the wash solution of the cell-saver. Effect on bacterial contamination
Revista Espanola De Anestesiologia Y Reanimacion. 2017;64((4):):185-191
OBJECTIVES The aim of this study is to test whether the addition of a low-dose of antibiotic (vancomycin) to the wash solution (saline) of the cell-saver reduces the incidence of bacterial contamination of the autologous red blood cell (RBCs) concentrate recovered. MATERIAL AND METHOD Experimental, randomized, double-blind, parallel group study performed on 20 consecutive patients scheduled for posterior spinal fusion surgery. Intraoperative bleeding was processed through a cell-saver: HaemoLite(R) 2+, in which the RBCs were washed according to randomization group, with saline (control group) or saline+10mug/ml-1 vancomycin (vanco group). Data regarding age, weight, processed and recovered volume, blood count, blood culture, and vancomycin concentration in RBCs concentrates obtained and incidence of fever after reinfusion were collected. RESULTS Processed volume was 843+/-403ml and recovered volume 121+/-29ml, with haemoglobin concentration 10.4+/-5.0g/dl-1 and haematocrit 29.1+/-15.9% (mean+/-SD). Recovered RBC concentrate cultures were positive for coagulase-negative Staphylococcus in 5 cases (50%) of the control group while all cultures were negative in the vanco group (P=.016). The difference between the theoretical concentration of vancomycin administered and the concentration determined in the recovered RBC concentrate was 1.31mug/ml-1 (95% CI 1.19 to 1.43; P=.074). CONCLUSIONS The addition of vancomycin at a concentration of 10ug/ml-1 to the wash solution of the cell-saver achieved similar concentrations in the autologous blood concentrate recovered allowing for bacterial removal, with negative blood cultures in all cases.
Indications and outcomes of cell saver in adolescent scoliosis correction surgery: a systematic review
STUDY DESIGN Systematic Review. OBJECTIVE To determine the indications and outcomes for intraoperative cell salvage during adolescent scoliosis correction surgery by systematically reviewing all available evidence. SUMMARY OF BACKGROUND DATA Several blood conservation strategies exist to minimize the consequences of blood loss due to scoliosis correction surgery. The utility of intraoperative cell salvage has been contested in the literature with respect to benefits and cost. High quality randomized control trials are needed to help surgeons make an informed decision about including Cell Saver into their practice. METHODS The databases Medline, Embase, Ovid Healthstar, and PubMed were searched for English language literature investigating Cell Saver use during adolescent scoliosis correction surgery, mean ages 10-19 inclusively. Qualitative and quantitative findings from relevant studies are presented. RESULTS There were seven eligible studies that directly compared the use of Cell Saver (349 patients) against a Control (non-Cell Saver) group (244 patients). The majority of the demographic and hematologic data were consistent between both groups. The average volume of blood that was re-infused into patients in the Cell Saver group was 453.8 ml. Patients in the Cell Saver group received significantly fewer allogenic blood transfusions than the Control group, with 32.6% less intraoperatively, 45.9% less postoperatively, and 47.3% less perioperatively. On average, Cell Saver patients received 1.0 fewer unit of allogenic blood compared to the Control group patients. CONCLUSION Cell Saver reduces the demand for allogenic transfusion. This review supports the use of Cell Saver if the associated monetary costs are expected to be less than the cost of transfusing one unit of allogenic blood. LEVEL OF EVIDENCE 4.
Which is the best schedule of autologous blood storage for preoperative adolescent idiopathic scoliosis patients?
Scoliosis. 2015;10((Suppl 2)):S11.
BACKGROUND It is critically important for AIS patients to avoid perioperative allogeneic blood transfusions. Toward this aim, many institutes use autologous blood storage to perform perioperative transfusions. However, there is no standard timeline for collecting blood for storage. Therefore, the objective of this prospective cohort study was to compare the outcome of two different schedules for collecting autologous blood before operation in adolescent idiopathic scoliosis (AIS) patients. METHODS Inclusion criteria are AIS patients, younger than 20 years old, female, operated between 2009 and 2013 with posterior spinal fusion and instrumentation who had 1600 mL autologous blood collected before operation. A total of 61 patients were participated in this study. They were randomly divided into 2 groups based on the storage interval. Weekly group (1W-G) consisted of 30 patients with a total of 1600mL blood collected weekly beginning 4 weeks before the operation. Biweekly group (2W-G) consisted of 31 patients with a total of 1600 mL blood collected biweekly beginning 8 weeks before the operation. The instrumented levels, total bleeding, complications during blood transfusion, and hematological examinations (RBC, Hb, Hct, MCH, MCV, MCHC) were evaluated. A hematological examination was performed before blood collection, before the operation, and on postoperative days 1, 3, and 7. Vasovagal reflex (VVR) was evaluated as complications during blood drawing. RESULT Mean age, height, and weight did not differ significantly between the 2 groups. There were no significant differences in instrumented levels, bleeding during operation, after operation, and collected blood during operation. With the autologous blood, allogeneic blood transfusion was completely avoided. VVR was more frequent in the biweekly group significantly (1W-G 4.2% vs 2W-G 15.3%). In terms of hematological examination, all values showed no significant differences between two groups in the pre-drawing and the pre-operation stage. However, the postoperative Hb and Hct values were higher in the weekly group. Also, MCV and MCHC showed the same behavior with higher values in the weekly group. CONCLUSION A weekly schedule of autologous blood storage is better than a biweekly storage schedule.
Does intraoperative cell salvage system effectively decrease the need for allogeneic transfusions in scoliotic patients undergoing posterior spinal fusion? A prospective randomized study
European Spine Journal. 2015;24((2):):270-5.
PURPOSE To determine the safety and efficacy of intraoperative cell salvage system in decreasing the need for allogeneic transfusions in a cohort of scoliosis patients undergoing primary posterior spinal fusion with segmental spinal instrumentation. METHODS A total of 110 consecutive scoliosis patients undergoing posterior instrumented spinal fusion were randomized into two groups according to whether a cell saver machine for intraoperative blood salvage was used or not. Data included age, body mass index, perioperative hemoglobin levels, surgical time, levels fused, perioperative estimated blood loss, perioperative transfusions and incidence of transfusion-related complications. A Chi-square test and t tests were performed for intraoperative and perioperative allogeneic transfusion between groups. A regression analysis was performed between selected covariates to investigate the predictive factors of perioperative transfusion. RESULTS Perioperative allogenic blood transfusion rate was lower in the cell saver group (14.5 versus 32.7 %, p = 0.025). Mean intraoperative red blood cell transfusion requirement was also lower (0.21 U/pt versus 0.58 U/pt, p = 0.032). A multivariate analysis demonstrated that no. of fused segments (OR: 1.472; p = 0.005), preoperative hemoglobin level (OR: 0.901; p = 0.001), and the use of cell saver system (OR: 0.133; p = 0.003) had a trend toward significance in predicting likelihood of transfusion. CONCLUSIONS Cell saver use significantly reduces the need for allogeneic blood in spine deformity surgery, particularly in patients with low preoperative hemoglobin or longer operation time. This study confirms the utility of routine cell saver use during PSF with segmental spinal instrumentation for scoliosis patients.