Perioperative autotransfusion in total hip and knee arthroplasty

We assessed the OrthoPAT Orthopedic Perioperative Autotransfusion System (Zimmer Inc, Warsaw, Ind) in reducing the need for allogeneic blood in hip or knee arthroplasty. Patients (N = 398) were divided into 5 cohorts: unilateral primary hip (n = 131), unilateral revision hip (n = 38), unilateral primary knee (n = 179), unilateral revision knee (n = 26), and bilateral primary knee (n = 24). Primary or revision hip arthroplasties with no preoperative autologous blood donation, knee arthroplasties with no preoperative autologous blood donation, and unilateral primary hip arthroplasties were 2.7, 2.3, and 2 times less likely (P < .05), respectively, to use allogeneic blood with OrthoPAT. We conclude that OrthoPAT use significantly reduced the risk of receiving allogeneic blood transfusions in defined patient subsets.     

Orthopaedic-induced anemia: the fallacy of autologous donation programs

Total knee arthroplasty is associated with significant blood loss. Despite the initiation of various blood conservation modalities, allogeneic transfusion has yet to be eliminated. One hundred forty-eight patients who had unilateral primary total knee arthroplasties during a 3-year period were evaluated retrospectively for blood loss and transfusion rates. The patients were prescribed one unit of preoperative autologous donation that was to be transfused automatically on postoperative Day 1. Allogeneic transfusion was based on symptoms, and no numerical transfusion triggers were used. The preoperative autologous donation program resulted in increased preoperative anemia. Whereas only 26.2% of patients were in the high transfusion-risk group (hemoglobin >10 g/dL and < or = 13 g/dL) before surgery, 55.7% of patients were in this high-risk category after preoperative autologous donation. The patients did not recover from the autologous donations that occurred 4 weeks before surgery. A mean hemoglobin level of 14.0 g/dL was seen before donation, whereas the mean preoperative hemoglobin level decreased to 12.6 g/dL. We think that a preoperative autologous donation program leads to an increased risk of anemia before surgery.     

Cost Minimization Analysis of Preoperative Erythropoietin vs Autologous and Allogeneic Blood Donation in Total Joint Arthroplasty

Autologous blood donation and erythropoietin (EPO) have been shown to be effective in reducing allogeneic blood transfusion, but the cost-effectiveness of these interventions remains unclear. A cost minimization analysis was performed, comparing the total costs of allogeneic blood transfusion strategy and autologous and allogeneic blood transfusion strategy for 161 primary total hip arthroplasty (THA) and 195 total knee arthroplasty (TKA) patients. An EPO cost minimization model was constructed using a previously published algorithm for blood management after total joint arthroplasty. The least costly strategy was autologous blood donation in combination with allogeneic blood for THA and TKA patients at $856 and $892 per patient, respectively. The most costly strategy was allogeneic only at $1769 and $1352 per THA and TKA patient, respectively. The EPO strategy model predicted costs similar to the autologous and allogeneic. A strategy that combines autologous blood donation with EPO for patients who cannot donate autologous blood may provide the greatest cost savings and minimize allogeneic blood transfusion.     

Targeted Preoperative Autologous Blood Donation in Total Knee Arthroplasty Reduces the Need for Postoperative Transfusion

Background

Preoperative donation of autologous blood has been widely used to minimize the potential risk of allogeneic transfusions in total knee arthroplasty. A previous study from our center revealed that preoperative autologous donation reduces the allogeneic blood exposure for anemic patients but has no effect for non-anemic patients.

Questions/Purposes

The current study investigates the impact of a targeted blood donation protocol on overall transfusion rates and the incidence of allogeneic blood transfusions.

Methods

Prospectively, 372 patients undergoing 425 unilateral primary knee replacements were preoperatively screened by the Blood Preservation Center between 2009 and 2012. Anemic patients with a hemoglobin level less than 13.5 g/dL were advised to donate blood, while non-anemic patients did not donate.

Results

Non-anemic patients who did not donate blood required allogeneic blood transfusions in 5.9% of the patients. The overall rate of allogeneic transfusion was significantly lower for anemic patients who donated autologous blood (group A, 9%) than those who did not donate (group B, 33%; p?<?0.001). Donating autologous blood did increase the overall transfusion rate of anemic patients to 0.84 per patient in group A compared to 0.41 per patient in group B (p?<?0.001).

Conclusion

This investigation confirms that abandoning preoperative autologous blood donation for non-anemic patients does not increase allogeneic blood transfusion rates but significantly lowers overall transfusion rates.     

Autologous blood transfusion in total hip arthroplasty

PURPOSE: To determine the possibility of avoiding homologous blood transfusion during total hip arthroplasty, and to clarify the problems associated with autologous blood transfusion. METHODS: A total of 253 patients received autologous blood transfusion during total hip arthroplasty between April 1990 and December 2000. Patients were assessed for the volume of haemorrhage during surgery, possibility of avoidance of homologous blood transfusion, and the disposal of autologous blood. RESULTS: There were no significant differences in the mean volume of haemorrhage among different underlying diseases. The mean total volume of haemorrhage was 2039 (standard deviation, 992) ml in revision surgery and 1673 (717.3) ml in primary surgery (p<0.05). The rate of avoidance of homologous blood transfusion was 75% among patients who underwent primary surgery, and 61% among those who underwent revision surgery. The rate was 95% in cases in which a combination of preoperative blood pooling and intra-operative recovery was used, 49% in cases where the preoperative blood pooling system alone was used, and 42% in those in which the intra-operative recovery system alone was employed. The autologous blood had to be disposed of in 3 (1%) cases, all of which were revision procedures with replacement of the polyethylene liner alone. CONCLUSION: Combined use of the preoperative blood pooling and intra-operative recovery systems is effective for avoiding homologous blood transfusion.     

A prospective,randomized study of preoperative autologous donation for hip replacement surgery

BACKGROUND: Preoperative autologous blood donation is commonly performed to meet potential perioperative transfusion needs and is a common practice prior to total hip arthroplasty. Using standardized transfusion guidelines, we prospectively analyzed the effectiveness of preoperative autologous donation as a method for decreasing allogeneic transfusion among patients undergoing unilateral primary total hip replacement who were eligible to donate autologous blood. METHODS: Patients who were scheduled for primary total hip replacement surgery and who had a preoperative baseline hemoglobin level >or=120 g/L were randomized either to donate two units of blood (autologous donors) or not to donate any blood (nondonors). The donors and nondonors were compared with regard to demographic data, blood-loss volumes, hemoglobin measurements, and transfusion rates. Randomization continued until data were obtained from at least forty patients per treatment group. RESULTS: Of the ninety-six patients who completed the study, forty-two were autologous donors and fifty-four were nondonors. There were no significant differences between the donors and nondonors with regard to age, male:female ratio, estimated blood volume, baseline physical condition, or operative blood loss. The hemoglobin values at the time of enrollment (baseline), at the time of hospital discharge, and six weeks postoperatively were not significantly different between the two groups, although values at the time of admission (129 +/- 13 g/L versus 138 +/- 12 g/L) and in the recovery room (104 +/- 12 g/L versus 115 +/- 13 g/L) were significantly lower in the autologous donor group (p < 0.05). No patient in either group required an allogeneic transfusion. Twenty-nine (69%) of the forty-two donors received an autologous transfusion. Thirty-four (41%) of eighty-two autologous units were wasted. At a charge of $379 per autologous unit, there was an additional cost of $758 for each patient in the donor group. CONCLUSIONS: Preoperative autologous donation provided no benefit for nonanemic patients undergoing primary total hip replacement surgery. Preoperative autologous donation increased the likelihood of autologous transfusion, wastage of predonated units, and costs.     

Analysis of transfusion predictors in shoulder arthroplasty

BACKGROUND: We are not aware of any previous study that has examined predictive factors for blood transfusion after shoulder arthroplasty. We analyzed the association between clinical factors and the need for postoperative blood transfusion and documented the use and waste of predonated blood in a group of patients managed with shoulder arthroplasty. METHODS: A retrospective study of 119 patients who underwent 124 shoulder arthroplasties (including eighty-seven primary uncomplicated total shoulder arthroplasties, twenty-seven revision or complicated primary total shoulder arthroplasties, and ten hemiarthroplasties) from 2001 to 2004 was performed. Logistic regression analysis was conducted to determine which clinical variables were predictive of transfusion. RESULTS: A postoperative transfusion was received after thirty-one arthroplasties (25%). The strongest predictor of blood transfusion after shoulder arthroplasty was the preoperative hemoglobin level (likelihood ratio test = 37.8, p < 0.0001). Patients with a preoperative hemoglobin level of between 110 and 130 g/L had a five times greater estimated risk of transfusion than those with a level of >130 g/L (p < 0.001). Gender, body mass index, preoperative diagnosis, comorbid conditions, use of anticoagulants or aspirin, autologous predonation status, type of anesthesia, operative time, and decrease in hemoglobin or hematocrit were not predictors of blood transfusion. One hundred and two (78%) of the 131 predonated autologous units were discarded. Patients with a preoperative hemoglobin level of >130 g/L had the highest percentage of wasted units (90%; fifty-five of sixty-one). Preoperative autologous blood donation did not eliminate the risk of allogeneic blood transfusion in autologous donors. CONCLUSIONS: The preoperative hemoglobin level is the strongest predictor of blood transfusion after shoulder surgery, and individuals with a preoperative hemoglobin level of <110 g/L have the highest risk of transfusion. On the basis of these findings, we do not recommend autologous predonation for individuals with a preoperative hemoglobin level of >130 g/L, to avoid unnecessary expense and waste.     

The reduction of preoperative autologous blood donation for primary total hip or knee arthroplasty: the effect on subsequent transfusion rates

We conducted this quality assurance observational study to examine the effects of a change in policy regarding preoperative autologous blood donation (PABD) and indications for perioperative blood transfusion in patients undergoing primary total hip or knee arthroplasty. Two successive time periods, each including 182 successive patients treated by the same medical team and with standardized anesthesia, were compared. The first study had the following standard transfusion policy: 3 U of PABD collected (n = 119) and liberal autologous transfusion (AT). The second study introduced a specific indication for PABD, on the basis of estimated red blood cell reserve and a life expectancy of more than 10 years; 2 U of PABD was collected (n = 81), and criteria were identical for AT and allogeneic transfusion. We mainly compared the incidence of AT; allogeneic and overall transfusions; the inclusion, admission, and discharge hematocrit values; and the wastage of PABD units. This novel policy increased the number of untransfused patients by a factor of 10 (5.5% vs 56.6%) (P < 0.0001), decreased the number of PABD patients by 30% with a 2.4-fold reduction in AT (30% vs 80%) (P < 0.0001), and did not change allogeneic requirements (13% vs 15%). Although fewer autologous units were collected (172 vs 426), the wastage was higher in Study 2 (46% vs 12%) (P < 0.0001). We conclude that incorporation of patients' individual factors improves the efficiency of transfusion for total hip and total knee arthroplasty surgeries. IMPLICATIONS: We compared two transfusion policies for primary total hip or knee arthroplasties: first, a standard preoperative autologous donation with a liberal autologous transfusion policy; and second, a more restrictive indication for autologous donation that was based on patients' individual factors, with identical criteria for autologous and allogeneic transfusion. We found that this change of policy reduced autologous donation and transfusion with no increase in allogeneic transfusion.     

The effects of preoperative autologous donations on perioperative blood levels

The purpose of this study was to evaluate the blood levels of patients preparing for total knee arthroplasty (TKA) who were enrolled in a preoperative autologous donation program. The charts and hospital records of 70 consecutive patients who underwent primary unilateral TKA between 2000 and 2002 were retrospectively reviewed. Study participants were instructed to donate one unit of blood approximately 4 weeks prior to surgery. Predonation and preoperative hemoglobin levels were assessed throughout the study and transfusion requirements were recorded. Transfusions were administered only when warranted by clinical symptoms. The mean initial (predonation) hemoglobin concentration was 14.1 g/dL. The mean number of days donations were made prior to surgery was 13 +/- 3.3 days. Prior to surgery, the average hemoglobin concentration dropped to 12.8 g/dL. Fifty (71%) patients had a hemoglobin value > 13.0 g/dL prior to their autologous donation, but only 30 (43%) patients had blood levels > or = 13.0 g/dL following blood donation. Postoperatively, the mean hemoglobin concentration in the recovery room was 11.6 g/dL and dropped to a nadir of 10.8 g/dL on postoperative day 3. Overall, 91% of patients required autologous blood transfusion following TKA but no patients required allogeneic blood transfusions. Preoperative autologous donation was associated with a decrease in preoperative hemoglobin levels and with a high rate of autologous transfusion based on clinical symptoms of postoperative anemia.     

Mannheim concept of preoperative autologous blood donation and perioperative autologous blood transfusion in hip endoprosthesis surgery

PURPOSE: To investigate the efficiency of preoperative autologous deposit and intra- and postoperative cell salvage (CS) to reduce homologous transfusion in hip arthroplasty and revision hip arthroplasty. METHODS: In a retrospective study, the data of 1402 patients scheduled for hip arthroplasty and for revision hip arthroplasty were analysed. RESULTS: 767 women and 635 men, age 62.9 +/- 9.8 years (x +/- s) were included in the study. 1270 were scheduled for hip arthroplasty, 132 for revision hip arthroplasty. Of the autologous donors, 51 patients predeposited four units, 1020 patients three, 204 patients two, 39 patients one unit. 88 patients who had not enrolled in the autologous donation program but received CS served as a control group. Blood loss in autologous donors amounted to 1620 (220-5620) ml in hip arthroplasty and 2830 (950-7910) ml in revision arthroplasty. CS was employed in part of the cases in arthroplasty and in all revision operations. 470 (0-2200) ml and 705 (0-2200) were retransfused. In hip arthroplasty 227 of 1182 patients (19.2%) received homologous blood. Homologous transfusion in patients with coxarthrosis due to acetabular protrusio, avascular necrosis of the femoral head and hip dysplasia showed a trend to higher values. Patients who had donated 3 units and received CS required homologous transfusion in 12.4% of the cases. CS reduced the homolgous transfusion rate significantly if the preoperative hemoglobin concentration was < or = 12 g/dl. A group of autologous donors receiving CS was matched with patients receiving CS only. 12 of 76 (15.8%) vs. 45 of 76 (59.2%) required homologous transfusion. In revision hip arthroplasty 58 of 132 patients (43.9%) required homologous blood. CONCLUSIONS: Preoperative deposit reduces homologous transfusion requirements considerably in hip surgery. Under the conditions studied CS should be employed in hip arthroplasty in addition to preoperative deposit if the preoperative hemoglobin concentration falls below 12 g/dl. In revision arthroplasty, 4 or more autologous units should be predeposited and CS should be used regularly.     

Blood loss and transfusion rates in bilateral total knee arthroplasty

From 1994 to 1998, we performed 170 bilateral total knee arthroplasties (TKAs) with cemented, posterior cruciate-substituting prostheses. Blood management included preoperative autologous donation, symptom-based transfusion, and autoreinfusion devices. Perioperative allogeneic transfusion rates for patients who donated 0, 1, 2, 3, or 4 units of blood were 40.00%, 0.00%, 3.70%, 0.00%, and 3.23%, respectively. Preoperative autologous donation >2 units also resulted in lower preoperative hemoglobin levels. For bilateral TKA, a protocol of 2 preoperative autologous donation units and reinfusion of postoperative drainage reduces anemia during the preoperative and postoperative periods.     

Targeted pre-operative autologous blood donation: a prospective study of two thousand and three hundred and fifty total hip arthroplasties

Purpose

Pre-operative donation of autologous blood has been widely used in elective joint replacement procedures to avoid the risks of allogeneic blood transfusions. However, the high percentage of wasted autologous blood questions the general efficacy of pre-operative autologous blood donation (PABD) for all patients undergoing hip replacement. This study prospectively investigates the impact of a targeted pre-operative autologous blood donation protocol for anaemic patients on allogeneic and overall transfusion rates in 2,350 unilateral primary total hip arthroplasty procedures.

Methods

Patients with pre-operative haemoglobin less than 12.5 g/dL were advised to donate one unit of autologous blood seven to 15 days prior to the date of surgery. The targeted protocol was followed by 2,251 patients: 280 out of 367 anaemic patients donated while 1,971 out of 1,983 non-anaemic patients did not donate.

Results

Results showed a significantly lower rate of allogeneic transfusion for anaemic patients who predonated than anaemic patients who did not (13 % vs. 37 % respectively, p < 0.001). Overall transfusion rates for patients who followed the protocol (n = 2,251) were found to be 0.17 units/patient compared to previously reported numbers of 0.75 units/patient when routine donation was used. Among the 2,251 patients who followed the protocol, only 140 patients (6 %) had their autologous blood wasted, in contrast to values reported in the literature ranging from 14 % up to 50 %.

Conclusions

Targeted PABD reduces the need for allogeneic blood transfusion in anaemic patients and significantly reduces the overall number of transfusions compared to routine pre-operative autologous donation.     

Does the Use of Erythropoietin Reduce the Risk of Exposure to Allogeneic Blood Transfusion in Cardiac Surgery? A Systematic Review and Meta‐Analysis

BACKGROUND: The use of blood conservation techniques is important in cardiac surgery as postoperative bleeding is common and allogeneic blood transfusion carries the risk of transfusion reactions and infection transmission. Erythropoietin with and without preoperative autologous blood donation is one of the modalities to avoid allogeneic blood transfusion. The objective of this review was to assess the effectiveness of erythropoietin in reducing the risk of exposure to allogeneic blood transfusion during or after cardiac surgery. METHODS: A meta-analysis of 11 identified randomized controlled trials, reporting comparisons between erythropoietin and control, was undertaken. The primary outcome was the number of patients exposed to allogeneic blood transfusion during or after cardiac surgery. RESULTS: Eleven studies, involving 708 patients, met the inclusion criteria for this review. In total, 471 patients were given erythropoietin, and 237 patients formed the control group. The administration of erythropoietin with and without preoperative autologous blood transfusion prior to cardiac surgery is associated with a significant risk reduction: RR = 0.28 (95% CI 0.18-0.44, P < 0.001) and RR = 0.53 (95% CI 0.32-0.88, P < 0.01), respectively. CONCLUSION: The administration of erythropoietin before cardiac surgery is associated with a significant reduction in the risk of exposure to allogeneic blood transfusion. Further studies are warranted to define the patients' subgroups that may benefit the most from EPO administration.     

Blood management in revision total knee arthroplasty

Much attention has been focused on blood management issues in orthopaedic surgery in recent years, but blood management in patients having revision total knee arthroplasty is not well-established. Hematologic values and transfusion records of 100 patients (52 women, 48 men; mean age, 65 years) who had aseptic revision total knee arthroplasty at the authors' institution were evaluated retrospectively. Two- or three-component revisions comprised 66% of the procedures, and 58 patients participated in a preoperative autologous donation program. The mean preoperative hemoglobin level was 12.1 g/dL in the women and 14.1 g/dL in the men, but the men experienced a greater decrease in hemoglobin level (mean largest decrease, 4.2 g/dL versus 3.1 g/dL), possibly caused by the higher allogeneic transfusion rate in women (19.2%) versus men (4.2%). Patient age did not influence hemoglobin level or transfusion rates. Patients who participated in a preoperative autologous donation program had significantly higher hemoglobin levels before donation (14.4 g/dL versus 13.3 g/dL for patients who did not participate in a program) but comparable hemoglobin levels after predonation (12.9 g/dL). Patients with preoperative hemoglobin levels less than 13 g/dL were significantly more likely to have a transfusion. Symptom-based transfusion strategies and blood management approaches such as epoetin alfa that elevate preoperative hemoglobin level therefore may be beneficial in patients having revision total knee arthroplasty.     

Ten-year follow-up on Dutch orthopaedic blood management (DATA III survey)

Introduction

Hip and knee arthroplasties are frequently complicated by the need for allogeneic blood transfusions. This survey was conducted to assess the current use of perioperative blood-saving measures and to compare it with prior results.

Materials and methods

All departments of orthopaedic surgery at Dutch hospitals were sent a follow-up survey on perioperative blood-saving measures, and data were compared to the results of two surveys conducted 5 and 10 years earlier.

Results

The response rate was 94 out of 108 departments (87 %). Most departments used erythropoietin prior to hip and knee replacements at the expense of preoperative autologous blood donation. The use of intraoperative autologous retransfusion in revision hip (56 vs. 54 %) as well as revision knee arthroplasty (26 vs. 24 %), was virtually unchanged. Postoperative autologous retransfusion is still used by the majority of departments after both primary arthroplasty and revision of hip (58/53 %) and knee (65/61 %).

Conclusions

Currently, just as in 2007, the majority of Dutch orthopaedic departments uses erythropoietin, normothermia and postoperative autologous retransfusion with hip and knee arthroplasty. Intraoperative retransfusion is used mainly with hip revision arthroplasty. Other effective blood management modalities such as tranexamic acid have not been widely implemented.     

Autologous blood transfusion in revision hip arthroplasty. A prospective, controlled study of 30 patients.

In a prospective, randomized study of the efficacy and effects of autologous blood transfusion in revision hip arthroplasty, 30 patients were randomly allocated into two groups. The Control Group received homologous blood transfusion. The Study Group deposited 2-3 units of blood preoperatively, intraoperative blood salvage was used, and no homologous blood was transfused intraoperatively. There was a smaller postoperative blood loss in the Study Group. The preoperative hemoglobin values were lower in the Study Group, but one week postoperatively they were higher than in the Control Group. The decrease in the values of AT III and protein C was lower in the Study Group. The combination of preoperative blood donation and intraoperative blood salvage reduced blood loss and homologous blood transfusion in revision hip arthroplasty.     

麻醉后预存自体血在人工关节置换术中的应用

目的探讨麻醉后即刻采集自体血,于人工关节置换术后回输的临床应用. 方法 2004年9月～2005年1月,对33例拟行人工关节置换术的患者,麻醉后即刻采集自体血400 ml,于术后回输.观察采血时患者血压变化、术后12、24及72 h血常规、伤口引流及感染情况.其中男17例,女16例,年龄33～81岁,平均62.4岁.类风湿性关节炎5例,股骨头坏死23例,膝关节骨性关节炎5例.单髋关节置换20例,双髋关节置换1例;单膝关节置换6例,双膝关节置换5例;单髋关节翻修术1例. 结果采血前后血压无明显变化.术后回输血200～1 150 ml,平均650 ml.其中21例单髋关节置换患者仅回输预存自体血;6例单膝关节置换患者回输预存自体血后又将引流血回输;5例双膝及1例双髋关节置换的患者除用预存自体血和引流血回输外,因术后出血较多,输入异体血400 ml.术后血红蛋白68～102 g/L,平均88 g/L;红细胞压积20.5%～31.5%,平均24.6%,与术前比较差异均有统计学意义（P〈0.01）.术后伤口无感染、下肢静脉无血栓发生.6例输入异体血的患者,输血后2例出现寒战、皮肤骚痒等过敏反应,予地塞米松后症状均缓解. 结论对行人工膝、髋关节置换术的患者术前预存自体血供术后回输,可减少术后输入异体血带来的危险.     

Perioperative blood salvage as an alternative to predonating blood for primary total knee and hip arthroplasty

A total of 200 consecutive patients who underwent primary total knee or hip arthroplasty were reviewed to assess the efficacy of perioperative blood salvage and retransfusion. Five of 132 (3.8%) patients undergoing total knee arthroplasty and 3 of 68 (4.4%) patients undergoing total hip arthroplasty required allogeneic transfusion in addition to retransfusion of salvaged autologous blood. The risk of receiving allogeneic transfusion in addition to retransfusion of salvaged blood was 1.2% (2 of 173) in patients with a preoperative hematocrit of > or=37%. The risk of requiring allogeneic transfusion was 22% (6 of 27) in patients with a preoperative hematocrit of 37%.     

Blood management for patients with hemoglobin level lower than 130 g/l in total knee arthroplasty

Introduction The risk of requiring allogeneic blood transfusion after total knee arthroplasty has been recently decreased with several methods such as blood donation, blood salvage, and hematinic. For patients with a low baseline hemoglobin level, however, the rate of allogeneic transfusion is still high, and an effective method for avoiding allogeneic blood transfusion has not been established. We introduced intra- and postoperative blood salvage with the Cell Saver for patients with a baseline hemoglobin level lower than 130 g/l and analyzed the frequency of allogeneic blood transfusion.Materials and methods From 1993 to 1997, 218 consecutive total knee arthroplasties were performed, and 155 knees with baseline hemoglobin lower than 130 g/l were included in this study. Baseline hemoglobin ranged from 62 to 129 g/l, with a mean of 110 g/l. All patients were managed with intra- and postoperative blood salvage with the Cell Saver. Preoperative autologous blood donation and/or use of hematinic was performed for 129 knees (group 1) and was not performed for 26 knees (group 2). There were no significant differences between the two groups with regard to preoperative factors. To examine the role of perioperative factors (age, sex, baseline hemoglobin level, revision procedure, preoperative blood donation, and use of hematinic) in determining the requirements for allogeneic transfusion, backward elimination logistic regression analysis was used.Results Seven knees (4.5%) required allogeneic transfusion. Group 1 (2.3%) exhibited a lower rate of allogeneic blood transfusion than group 2 (15.4%) (p=0.016). Hemoglobin levels on the day (p=0.016), 1 week (p=0.0001), and 2 weeks (p=0.007) after surgery were lower in group 1 than in group 2. Backward elimination logistic regression analysis showed that preoperative blood donation (p=0.048) and use of hematinic (p=0.040) were significantly associated with a requirement for allogeneic blood transfusion.Conclusion Preoperative blood donation and use of hematinic were associated with a low incidence of allogeneic blood transfusion after total knee arthloplasty with intra- and postoperative blood salvage, even for patients with a baseline hemoglobin level below 130 g/l.     

Minimal effective dosage of recombinant human erythropoietin in spinal surgery

Preoperative autologous blood donation is one of the most widely used methods of autotransfusion. However securing a predetermined amount of blood (3 units of whole blood) may be difficult in patients with a low preoperative hematocrit. To determine the minimum effective pretreatment dosage of recombinant human erythropoietin required to secure an adequate amount of preoperative blood for autologous transfusion during posterior decompression and instrumentation fusion using the pedicle screw-rod system in the lumbar spine, a prospective randomized clinical trial was done. Forty-five patients who had a preoperative hematocrit less than 40% were selected and were divided blindly into three groups. Fifty units per kilogram of recombinant human erythropoietin seems to be the minimal effective dosage for securing an adequate amount of preoperative autologous blood donation.