The efficacy of intraoperative autologous transfusion in major orthopedic surgery: a regression analysis

Intraoperative cell salvage versus postoperative autologous blood transfusion in hip arthroplasty: a retrospective service evaluation

INTRODUCTION

A number of ways of reducing blood loss in arthroplasty have been explored, including preoperative autologous transfusion, intraoperative cell salvage and postoperative autologous transfusions. Both intraoperative blood salvage and postoperative retransfusion drains have been shown to be effective in reducing blood loss in total hip arthroplasty. In our department there was a change in practice from using postoperative retransfusion drains to intraoperative cell salvage. To our knowledge no study has directly compared using intraoperative blood salvage and postoperative retransfusion drains alone in total hip arthroplasty.

METHODS

This was a retrospective service evaluation including all primary hip arthroplasty performed under our care between January 2006 and December 2008. Patients were divided into two groups: Group A used a postoperative autologous blood transfusion (ABT) drain and Group B used intraoperative cell salvage.

RESULTS

A total of 144 patients were included in this study: 84 in Group A and 60 in Group B. The mean haemoglobin difference for Group A was 3.96g/dl (standard deviation [SD]: 1.52) and for Group B it was 3.46g/dl (SD: 1.42). The mean haematocrit difference for Group A was 0.12% (SD: 0.05) and for Group B it was 0.10% (SD: 0.04). Using an independent t-test for the comparison of means, a significant difference was found between Group A and B both in regards to haemoglobin difference (p=0.009) and haematocrit difference (p=0.046).

CONCLUSIONS

We feel that intraoperative cell salvage provides a more efficient method of reducing blood loss than postoperative retransfusion in primary total hip replacement. A prospective randomised study would be useful to ascertain any clinical difference between the two methods.

Cell Saver: is it beneficial in scoliosis surgery?

STUDY DESIGN

Review of the use of Cell Saver in a non-randomized group of patients undergoing spinal fusion for scoliosis.

OBJECTIVES

To determine the efficacy of the use of Cell Saver for spinal fusions for scoliosis. Although Cell Saver is widely used in scoliosis surgery, it is not clear whether its use decreases the need for other transfusions or whether there are certain patients more likely to benefit from its use. The blood collected by Cell Saver intraoperatively is not always of sufficient volume to be returned to the patient, and there are no current guidelines addressing the amount that is likely to be returned to the patient.

PURPOSE

The purpose of this study was to determine: Does use of Cell Saver reduce the need for other transfusions in scoliosis surgery? Is there an amount of blood loss at which Cell Saver is likely to be returned?

MATERIALS AND METHODS

The study group consisted of 95 children who had undergone posterior spinal fusion between January 2002 and March 2004 with one of two surgeons. One surgeon used Cell Saver, the other surgeon did not. Of the total, 58 patients who underwent posterior spinal fusion with the use of Cell Saver (group 1) were compared with the 37 (group 2) who underwent the same procedure without the use of Cell Saver.

RESULTS

Of those in group 1, 34 received Cell Saver blood back as an intraoperative autologous transfusion (IAT) (59%). Patients in the Cell Saver group were just as likely to receive non-Cell Saver transfusions as those in the control group (P = 0.12). Of the 39 patients who lost more than 500 cc of blood, 34 received IAT (87%). No patient who lost less than 500 cc of blood received IAT.

CONCLUSION

The use of Cell Saver does not reduce the need for other transfusions in scoliosis surgery. The amount of blood loss at which Cell Saver is likely to be returned is 500 cc. We demonstrated no benefit in the use of Cell Saver in our patient population.

Severe blood loss during spinal reconstructive procedures: The potential usefulness of topical hemostatic agents

Complex spinal reconstructive procedures are invariably associated with excessive intraoperative blood loss that significantly increases the risk of severe perioperative complications. In some cases, excessive hemorrhage is equivalent to estimated total blood volume. Unfortunately, widely exposed bony surfaces are not amenable to standard hemostatic maneuvers utilized during soft tissue surgery. This article evaluates the clinical effectiveness of several approaches to blood management in this setting, and hypothesizes that underappreciated topical hemostatic agents may provide benefit by reducing the need for autologous predonation, banked donor blood or antifibrinolytic agents. Topical agents combining collagen, thrombin and fibrin have demonstrated initial promise by inducing platelet aggregation and initiating the clotting cascade when applied directly to bleeding bony sites. Clinical studies are clearly warranted.

Intraoperative blood management in joint replacement surgery

Interest is growing in blood conservation and avoidance of transfusion in patients undergoing orthopedic surgery, especially in the field of joint replacement. Several methods have proven successful in reducing intraoperative blood loss, which can translate into lessened allogeneic and autologous transfusion requirements. Available techniques include acute normovolemic hemodilution, hypotensive anesthesia, intraoperative blood salvage, specialized cautery, topical hemostatic agents, and pharmacologic agents given in the perioperative period. The greatest potential benefit arises in operations with greater expected blood loss or in special situations such as in patients with religious issues, bilateral joint replacement, coagulation disorders, or significant preoperative anemia.

Autologous transfusion and other approaches to reduce allogeneic blood exposure

When used as the sole source of transfused blood, the principal advantage of autologous blood transfusion is the avoidance of transmission of infectious agents and the avoidance of the purported adverse immunomodulatory effects of allogeneic transfusion. In the 1990s, however, the risks of transfusion-transmitted diseases have been greatly reduced, and estimates of the cost-effectiveness of pre-operative autologous blood donations now vary between 2470 dollars and 3,400,000 dollars per quality-adjusted year of life saved, depending on assumptions about the existence and magnitude of any adverse immunomodulatory effects of allogeneic transfusion. There is a paucity of randomized controlled trials evaluating the clinical outcomes and the cost-effectiveness of autologous transfusion procedures, and this situation is unlikely to change in the near future because of the difficulties in conducting such trials. This chapter reviews the available evidence on the efficacy, safety and cost-effectiveness of the three common autologous transfusion procedures, that is, pre-operative autologous blood donation, acute normovolaemic haemodilution, and intra-operative and post-operative blood recovery.

Intraoperative autotransfusion is associated with modest reduction of allogeneic transfusion in prosthetic hip surgery

BACKGROUND

The efficacy of intraoperative salvage and washing of wound blood and the predictors of allogeneic red cell transfusions in prosthetic hip surgery are insufficiently known.

METHODS

In 96 patients, undergoing primary or revision surgery, salvaged and washed red cells and, if necessary, allogeneic blood were used to keep haematocrit not lower than 33%. The bleeding of red cells during hospital stay was calculated from the red cell balance. The preoperative red cell reserve (mililitres of red cells in excess of a haematocrit of 33%) was estimated and the difference between this volume and the total bleeding of red cells was retrospectively used to classify patients with regard to the need for red cells. Stepwise regression analysis was used to define patient-related variables associated with allogeneic blood transfusion.

RESULTS

Preoperative knowledge of the type of operation (primary, revision), the preoperative red cell reserve, and the body mass could predict roughly half of the need for banked blood (r2 = 0.45). Only one-third of the total bleeding of red cells was retransfused. For complete avoidance of allogeneic blood, autotransfusion was most effective in patients with a moderate need (0-4 u). However, 32% of such patients required allogeneic blood.

CONCLUSIONS

Autotransfusion has a limited efficacy to decrease the need for allogeneic blood, and other blood-saving methods should be added for this purpose. It is difficult to predict the need for allogeneic blood preoperatively.

Survival of autotransfused red cells. 51Cr studies in 10 knee arthroplasty patients

We determined the long-term survival of red blood cells collected postoperatively from the surgical drains, filtered and autotransfused with the Constavac Blood Conservation System. 10 patients with knee arthrosis were treated with cementless total knee arthroplasty and postoperatively connected to the autotransfusion system. Shed blood was collected for 6 hours postoperatively and then reinfused. Before reinfusion, a fraction of the blood shed was radiolabeled with chromium-51 (51Cr). For a postoperative minimum period of 40 days the activity of 51Cr was measured in frequent venous blood samples. The time from 100% to 50% activity of the isotope (T50Cr) was 21 days, equal to that reported for banked autologous blood.

Autologous blood procurement in the surgical setting: lessons learned in the last 10 years

The percentage of blood transfused yearly that is autologous has increased substantially over the last 10 years. While autologous blood is regarded as a standard of care in many elective surgical settings, the increasing safety of allogeneic blood and the expense of autologous blood procurement have raised question regarding the appropriate roles of autologous blood in blood conservation strategies. We therefore review current activities and emerging questions that arise from this maturing arena.

Intraoperative salvage in patients undergoing elective abdominal aortic aneurysm repair: an analysis of cost and benefit

PURPOSE

Although autologous blood procurement has become a standard of care in elective surgery, recent studies have questioned its cost-effectiveness. We therefore reviewed our 3-year experience with intraoperative cell salvage in patients who underwent elective abdominal aortic aneurysm repair.

METHODS

A 3-year retrospective chart review of elective abdominal aortic aneurysm (infrarenal and suprarenal) repair was performed. Transthoracic repairs were excluded.

RESULTS

Estimated blood lost was 1748 +/- 1236 ml, or 35% of baseline blood volume (5012 +/- 689 ml). Overall, 164 (89%) received red blood cell (RBC) transfusions (3.5 +/- 2.0 U/patient). The cost per patient for cell salvage was $315 +/- $97, representing 31% of all RBC costs and 24% of total blood component costs. Mean salvage volume infused was 578 +/- 600 ml; at a mean hematocrit level of 55.7% the RBC volume infused from salvage during surgery was 313 +/- 328 ml (representing 27% of total RBC volume lost during the hospital stay). This mean RBC volume salvaged represented the equivalent of 1.6 blood bank RBC units. The mean blood bank costs saved by using cell salvage was $248, or 79% of the $315 actually spent for salvage. We found no decrease in percentage of patients undergoing transfusion until salvage volumes that were infused exceeded 750 ml, or the equivalent of two blood bank units; all of these patients who benefitted had estimated blood lost > or = 1000 ml.

CONCLUSIONS

We conclude that use of intraoperative cell salvage was most beneficial for patients who had estimated blood loss greater than or equal to 1000 ml and cell salvage volumes infused greater than or equal to 750 ml. Patients who are estimated to lose less than 1000 ml receive little benefit yet incur substantial costs from intraoperative cell salvage.

Efficacy and cost considerations of intraoperative autologous transfusion in spinal fusion for idiopathic scoliosis with predeposited blood

STUDY DESIGN

One hundred five patients with adolescent idiopathic scoliosis who underwent posterior spinal instrumentation and fusion with predeposited autologous blood, with or without intraoperative autologous transfusion, were reviewed.

OBJECTIVE

To determine the benefit/nonbenefit of intraoperative autologous transfusion in diminishing the need for homologous blood and influencing post-operative hematocrit values in healthy adolescents undergoing spinal fusion for scoliosis.

SUMMARY OF BACKGROUND DATA

A steady increase in the use of intraoperative autologous transfusion in recent years has occurred without guidelines regarding which procedures and patient populations would be best served. Previous studies have failed to determine the cost effectiveness and actual reduction in homologous blood exposure attributable to intraoperative autologous transfusion in adolescents who have undergone preoperative phlebotomy.

METHODS

Fifty-five adolescents (intraoperative autologous transfusion group) who underwent posterior instrumentation and fusion for idiopathic scoliosis with the use of an intraoperative autologous transfusion device were compared to 50 patients (control group) who underwent the same procedure without the intraoperative autologous transfusion device.

RESULTS

The average percent salvage of red blood cells by the intraoperative autologous transfusion device was 35%. The control group utilized significantly more of the predonated autologous blood than the intraoperative autologous transfusion group (1.34 units/case vs. 1.78 units/case, P < 0.05). Homologous blood usage was the same in both groups. Two patients in the intraoperative autologous transfusion group required nondirected homologous blood (total of four units), compared to three patients in the control group (total of four units) (P = 0.048). Using multiple regression analysis, the total number of transfusions was significantly correlated with the estimated blood loss and the duration of surgery in both groups. Postoperative hematocrit levels were slightly higher in the control group, but there was not a significant difference.

CONCLUSIONS

The addition of intraoperative autologous transfusion to a preoperative phlebotomy program had no benefit on homologous blood exposure or post-operative hematocrit changes in this population. Blood requirements for this procedure can be met less expensively and more reliably by merely donating one's own blood.

The role of autologous blood transfusion in joint replacement surgery

The efficacy of predeposited autologous blood transfusion (PABT) with and without intra/postoperative blood salvage to reduce or eliminate the need for homologous blood transfusion (HBT) in primary total hip or knee replacement surgery was investigated by retrospective and prospective studies. Depending on the type of surgery, one to three units of PABT eliminated the need for HBT in 50 to 78% of patients, but, intra/postoperative blood salvage alone reduced the need only in 11 to 29%. In contrast, blood salvage, when combined with three units of PABT, eliminated the need for HBT in all patients undergoing primary joint replacement surgery. A cost comparison analysis showed that blood salvage was more expensive than PABT, and therefore it should be limited to patients who had predeposited fewer than three units of autologous blood.

Blood transfusion and blood conservation: cost and utilization issues

Approximately 12 million red blood cell units are transfused to nearly 4 million patients annually in the United States (1). The conservation of blood has historically arisen from awareness that the inventory of this resource is limited (2), as well as the knowledge that blood transfusion carries a risk (3). Estimates of current blood transfusion risks (4-12), and the costs of transfusion complications (13-17), are summarized in Table 1. In addition, emphasis on the costs of health care has raised issues related to the costs of blood transfusion (18, 19). Finally, recent guidelines have emphasized that in the elective transfusion setting, no blood transfusion is a desirable outcome (20, 21). Furthermore, these guidelines along with consensus conference recommendations (22) have emphasized that if blood is to be transfused, autologous (the patient's own) blood is preferable to allogeneic (from an anonymous, volunteer donor) blood. Thus, the costs of blood conservation, for which an increasing array of technologic procedures and products have become available (Table 2), have also become an issue (23). The purpose of this review is to provide an overview of emerging data on the cost-effectiveness of blood and blood conservation interventions in order to help identify areas important for future investigation.

Blood Conservation and Blood Salvage

Autologus blood transfusion has been recommended as the blood of choice for surgical patients. Procurement of autologus blood can be accomplished by utilizing one or more conservation interventions: preoperative autologous blood donation, acute preoperative hemodilution, and perioperative autologous salvage. Recent estimates of cost-effectiveness emphasize that blood conservation interventions need to be held accountable with regards to their costs as well as their benefits. Despite recent advances in blood safety, patients need to be informed of the relative risks of blood transfusion and blood conservation, so that a careful balance of the need for blood conservation along with an acknowledgment of the life-saving properties of blood can be maintained.

Intraoperative autotransfusion in hip arthroplasty. A retrospective study of 214 cases with matched controls

The transfusion requirements in 214 patients who received intraoperatively collected autologous blood during total hip arthroplasty (Study Group) were compared with 214 age- and sex-matched controls who received homologous bank blood (Control Group). There were 132 patients with primary operations, 27 bilateral, and 55 revisions in each group. In the Study Group, there was a reduction in the amount of homologous blood transfusion, intraoperatively as well as totally, and also in postoperative blood loss in all three operation subsets. The Study and Control Groups were equal in pre- and postoperative hemoglobin and hematocrit values.

Intraoperative autotransfusion in primary hip arthroplasty. A randomized comparison with homologous blood

To study the quality and effect of blood produced by the cell saver compared with homologous blood in total hip arthroplasty, 40 patients were randomly divided into two groups. One group received autologous blood using the cell saver, whereas the second group served as a control, and received homologous bank blood. Hematologic and coagulation parameters of the patients were assessed both preoperatively and postoperatively. Samples from the autologous and the homologous blood were obtained before reinfusion, and were assessed as regards hematologic and biochemical parameters. The autologous blood satisfied all the intraoperative transfusion requirements of the autologous group and 75 percent of the total transfusion requirements. The operative and postoperative blood losses--hence, the total blood loss--were less in the autologous than in the control group. The autologous blood had a high hemoglobin, white blood cell, and plasma hemoglobin content and MCV compared with the homologous blood. Postoperatively, there were no differences as regards the hematologic parameters studied. There was no evidence of intravascular hemolysis in the autologous group. Postoperatively, in both groups, AT III, plasminogen, and protein C decreased. Other coagulation parameters were within normal limits in both groups. Intraoperative autotransfusion is safe and effective, and should be considered in hip arthroplasty to reduce the risks associated with homologous blood transfusion.

Cost effectiveness of blood substitution in elective orthopedic operations

Cost effectiveness was compared between substitution with autologous blood, implying no risk of transmission of diseases, and homologous blood, with a definite risk of transmission. Primary and revision hip arthroplasties were included in this study, as well as scoliosis operations. The risk of contracting chronic non-A, non-B hepatitis (NANBH) was included in the calculations of the long-term economic consequences of a transmittable disease. Our study showed that predonated blood alone, with a donation of up to four units, was the most suitable and cost-effective method for substitution of blood losses up to about 2.5-3 liters A combination of predonated blood and intraoperative autotransfusion was more suitable and less expensive for substituting blood losses of 2.5 liters or more. Homologous blood was the least cost-effective alternative considering the influence of non-A, non-B hepatitis.

Efficacy of intraoperative autotransfusion in primary total hip arthroplasty

The role of intraoperative autotransfusion in diminishing perioperative transfusion requirements was studied in 64 patients undergoing primary total hip arthroplasty. The total transfusions administered in a 3-day perioperative period were tabulated for the study group (in which intraoperative autotransfusion was utilized) and compared to that of the control group. Despite the use of the Cell Saver autotransfusion device, no significant difference was noted between the total units of blood transfused perioperatively in the two groups. Moreover, calculations of mean perioperative blood loss (intra- and postoperative) were not significantly different, nor was there any difference in mean hemoglobin concentrations between the two groups on the third postoperative day. All 64 patients received 4 units or less of banked blood in the perioperative period. The authors conclude that this modality of blood conservation is not necessary in primary hip arthroplasty and that a well planned autologous prebanking program should be sufficient in the vast majority of cases to avoid the use of banked homologous blood.

Intraoperative autotransfusion in reconstructive hip joint surgery of patients with rheumatoid arthritis and ankylosing spondylitis

The efficacy of a simple, low-cost device designed for intraoperative blood salvage and reinfusion, known as the Sorensen system, was studied during 24 hip joint operations in adult patients suffering from rheumatoid arthritis or ankylosing spondylitis. The total need for homologous blood was reduced to 28%, compared with a matched control group of patients who had previously undergone hip surgery by homologous blood replacement. In primary hip-replacement operations, the need for blood was met either completely by autotransfused blood or by the addition of 1 or 2 units of homologous blood. In revision arthroplasties, the maximal need for homologous blood was 6 units owing to a greater blood loss during operation. Postoperative changes in several hematologic variables measured were all very small. The autotransfusion system proved easy and safe to operate. No patients manifested complications. In our experience, the system may be considered an underutilized resource in rheumatological surgery.

Developing techniques in blood transfusion

Expansion of transfusion medicine has led to an increasing awareness of the importance of its practice. Specialists in this branch of haematology whose main aim is to provide adequate and safe supplies of blood (and blood products) and to ensure these are used appropriately, are increasingly aware that to do this efficiently requires the development and utilization of new laboratory and technical procedures. Review of cross-matching techniques has led to the introduction of more rapid methods using low ionic strength saline. Use of monoclonal antibodies for blood grouping has made use of new technology, whilst allowing scarce human plasma to be used more appropriately for therapeutic purposes. Similarly, the implementation of a more rational approach to blood ordering, as in a maximum surgical blood-order schedule, allows for the more efficient use of donor blood. The use of microtitre plates for grouping and cross-matching techniques allows for speed and economy in the transfusion laboratory. Their use is also associated with increased automation and computer use. The possibility of using solid-phase techniques, monocyte-macrophage assays and antibody-dependent cellular cytotoxicity assays introduces new techniques differing markedly from time-honoured liquid-phase serology methods. The application of flow cytometry, which has already been shown to be useful in many aspects of haematology, is also of benefit in the field of blood transfusion science. Safety of blood transfusion is an important aspect of its practice and has led to the introduction and development of screening tests for donor blood to exclude infection risks from such organisms as HIV-1, hepatitis B and non-A, non-B hepatitis. Another approach to ensure the safety of transfused blood has been increased usage of autologous transfusion by means of both predeposit donation and intraoperative cell salvage.

The impact of preoperative autologous blood donation on orthopaedic surgical practice

We have conducted a retrospective 3-year analysis of our autologous blood donation program to assess its impact on orthopaedic surgery. We conclude: (1) utilization has increased from less than 5% of eligible patients in the first audit interval to nearly 50% in the last audit interval; (2) in the last audit interval, autologous blood donation resulted in a reduction of homologous blood transfusion from 41% in nonautologous blood patients to 14% in autologous blood donors; (3) increasingly conservative transfusion practice is seen for all patients undergoing elective orthopaedic surgery; (4) regional blood centers are responding to increasing requests for autologous blood with programs that are effective in attracting autologous blood donors; (5) on the basis of utilization and efficacy, preoperative autologous blood donation as an alternative to homologous blood transfusion now represents a standard of practice for elective orthopaedic surgery.

Intraoperative blood salvage

Interest in and use of IBS have increased recently. This form of haemotherapy involves the retrieval of blood shed perioperatively. IBS, together with other forms of ABT, has gained a prominent role in transfusion medicine, largely due to an increased awareness of the risks associated with transfusion of homologous blood. In addition to conserving erythrocytes, IBS prevents disease transmission, other adverse transfusion reactions, and alloimmunization to antigens in blood cells and plasma which may result from homologous blood use. An array of IBS devices is presently available, ranging from disposable canisters to complete processing systems. The devices are capable of recovering, filtering, washing and reinfusing shed erythrocytes. They can be divided into slow-flow and rapid-flow systems based on the rapidity of blood processing. Most systems use a dual channel aspiration cannula through which shed blood is aspirated and mixed with anticoagulant solution. The salvage procedure requires operator control at every step, even for the highly automated instruments. Various health care personnel have been trained to operate IBS equipment; a transfusion service nurse with blood bank expertise has proved to be a highly reliable operator in our practice. Extensive clinical observation has shown that salvaged erythrocytes function and survive normally. IBS has been applied in many surgical fields; it has two relative contraindications: its use in areas affected by infection or malignancy. Operative procedures characterized by large blood losses provide a cost-efficient application of IBS, including cardiac surgery, orthopaedic procedures, trauma, vascular surgery, and liver transplantation. New, highly efficient technology is emerging that is capable of recovering other blood components. Consequently, what presently amounts to erythrocyte recovery will be expanded shortly to include platelets and plasma, with its many constituents.

Intraoperative autologous transfusion in primary and revision total hip arthroplasty

Significant blood loss during total hip arthroplasty is usually unavoidable. Blood loss is even more of a problem during revision total hip arthroplasty. Using the Cell-Saver for retrieval of red blood cells to be used for autotransfusion during surgery is a safe and useful way of sparing donor blood transfusion. This is a retrospective analysis of primary and revision total hip arthroplasty cases and comparison between cases in which Cell-Saver was used versus those in which Cell-Saver was not used. Generally accepted standards to determine the need for blood transfusion, including measured serum hemoglobin and patient symptoms and vital signs, were used as guidelines in treating patients. Using multiple regression models and taking into account certain variables between cases, it was determined that a significant amount of donor blood transfusion can be saved when the Cell-Saver is used. The Cell-Saver is an important aid in intraoperative treatment for both primary and revision total hip arthroplasty cases.