Autologous Blood Conservation Research Articles

Implementation of an electronic identification system in the setting of perioperative autologous cell salvage transfusion: Experience at a university hospital

Perioperative autologous cell salvage (PACS) is one of the effective strategies in patient blood management (PBM). However, mistransfusion, in which the wrong blood is transfused to the wrong patient, of PACS units has been reported. In this study, we implemented a bar code-based electronic identification system (EIS) for blood transfusion in the setting of PACS transfusion. Between February 2009 and December 2020, a total of 12341 surgical patients (9% of whom received surgical interventions) received blood transfusion, among whom 6595 (54 %) received autologous blood transfusion alone, 2877 (23 %) both autologous and allogeneic blood transfusions, and 2869 (23 %) allogeneic blood transfusion alone. Among autologous blood conservation techniques, PACS units were transfused to 7873 patients (83 %) without a single mistransfusion. Rates of overall compliance with the electronic pre-transfusion check at the bedside for all autologous units and PACS units were 98.8 and 98.5 %, respectively. Our observations suggest that a bar code-based EIS can be successfully applied to PACS transfusion, as well as allogeneic blood transfusion in operating rooms.

Ranking the effectiveness of autologous blood conservation measures through validated modeling of independent clinical data

Future supply with allogeneic blood transfusions faces several crucial challenges that warrant thorough (re-)evaluation of existing alternatives. Meta-analyses have indicated a significant potential for autologous blood conservation (ABC) measures to reduce the need for allogeneic blood transfusions. The quality of currently available studies, however, prohibits definite conclusions. Under these circumstances, mathematical modeling offers unique opportunities to compare various ABC measures and to test the impact of different variables on efficacy and effectiveness. We performed an extensive search for clinical ABC studies, focusing on acute normovolemic hemodilution (ANH), intraoperative blood salvage (IBS), or preoperative autologous deposit (PAD). Only ABC studies providing a minimum set of clinical variables were included. Using a clinically validated mathematical model, we then calculated maximal allowable blood loss (efficacy) and increase in red blood cell (RBC) mass (effectiveness) to rank the three techniques. We identified 21 clinical ABC studies, including 3926 patients, as suitable for our model. Our model shows that IBS with high recovery rates is the most efficacious and effective ABC measure. PAD will reveal nearly similar efficacy and effectiveness, only if sufficient time for RBC regeneration has passed and if 4 PAD units or more are available. Our model further demonstrates that ANH as well as IBS with low recovery rates are the least efficacious and effective alternatives. IBS appears to be the most efficacious and effective ABC measure. PAD can only reduce the need for allogeneic blood transfusions under certain circumstances. ANH does not appear to play an important role in ABC.

Autologous blood in obstetrics: where are we going now?

In developed countries1, pregnancy-related transfusion accounts for about 6 percent of red blood cell (RBC) units transfused. This means that, for example, in the UK as a whole, approximately 70,000 units of RBC are transfused to obstetric patients each year2. The pattern of blood usage is very different in countries in which diagnostic and treatment options are more limited, with 37 percent of transfusions being given to women with obstetric emergencies1. Obstetric haemorrhage is a leading cause of maternal and perinatal mortality3. Placental abruption and placenta praevia/accreta can present as antepartum haemorrhage and are risk factors for post-partum haemorrhage (PPH). Uterine atony, inversion, retained products of conception and genital tract trauma all cause PPH and account for the majority of cases of major haemorrhage. Uterine rupture is an infrequent cause of haemorrhage and maternal death and can occur spontaneously or at the site of previous uterine surgery (caesarean section or retained placenta)3. During the triennium 2006–2008, the rate of deaths from hemorrhage in the UK was 0.39 per 100,000 maternities4. The incidence of severe bleeding in childbirth has been estimated in various surveys and is approximately one in 200 to 250 deliveries4. In developed countries treatment is generally effective with an approximate case fatality rate between 1 in 600 to 800 cases of obstetric bleeding5–7. Various blood conservation techniques can reduce exposure to allogeneic blood. These include pre-operative autologous blood donation (PABD), acute normovolaemic haemodilution (ANH) and intra-operative blood salvage (IBS). PABD may cause anaemia, does not eliminate transfusion risk, cannot be used in an emergency, is not acceptable to Jehovah’s Witnesses and should be reserved for exceptional circumstances8,9. ANH may induce anaemia and cardiac failure, cannot be used in an emergency and may have a limited role in combination with other techniques9. The use of IBS has increased substantially during the last two decades and the re-infusion of shed washed blood is commonplace in many types of surgical operations in which heavy blood loss is anticipated10,11. In this technique, blood shed at the time of surgery is collected and washed, and RBC are returned to the patient as an ongoing process (Figure 1)12,13. In skilled hands, blood salvage can be quickly set up and the final product returned to the patient within minutes of collection. In addition, this technique is also acceptable to some Jehovah’s Witnesses, provided the equipment is set up in continuity with the circulation (Figure 1)14, but consent needs to be obtained on an individual basis. Figure 1 Schematic representation of a blood salvage system with a double suction setup to reduce the possible contamination of the blood suctioned from the surgical field138. In this setup, one suction line is connected to the collection reservoir and used for ... However, the safety of IBS in obstetrics has been questioned and its introduction in this clinical arena has been delayed because of theoretical concerns stemming from the historical and ongoing dispute focused on the risk of maternal-foetal anti-Rh(D) alloimmunisation and the risk of contamination of the cell-saved blood with traces of amniotic fluid (AF)15,16. The objective of this article is to review the role of autologous blood conservation techniques in obstetrics focusing on the currently available evidence regarding IBS. An overview of current European regulatory requirements on IBS will also be provided.

Pre-operative autologous blood donation: clinical parameters and efficacy.

Pre-operative autologous blood donation (PABD) aims to provide a supply of safe blood for patients undergoing surgery who might need a blood transfusion while at the same time increasing the patient's total red blood cell (RBC) mass due to the PABD-induced stimulation of erythropoiesis before scheduled elective surgery. This can, however, only be accomplished if the determinants of RBC regeneration are understood. The improvement of viral safety of allogeneic blood products following the introduction of molecular techniques has led to a decline in the use of autologous blood conservation (ABC) measures, and in particular in the use of PABD. More rational and restrictive indications for allogeneic blood transfusion have evolved and led to a further decrease in the relevance of PABD.

Reinfusion of Blood within Aneurysm Sac: A Simple Method of Intraoperative Blood Conservation in Elective Abdominal Aortic Surgery

Autologous blood conservation reduces postoperative morbidity and mortality. In elective abdominal aortic aneurysm repair, the blood within the aneurysm sac is generally neglected during surgery. We present a simple method of additional blood conservation in elective abdominal aortic surgery, which involves reinfusion of autologous blood within the aneurysm sac in the perioperative period.

Compatibility of different colloid plasma expanders with perflubron emulsion: an intravital microscopic study in the hamster.

Perfluorocarbon-based oxygen carriers have been proposed as an adjunct to autologous blood conservation techniques during elective surgery. To date, the effects of perfluorocarbon emulsions at the microcirculatory level have not been studied extensively. In this study the effects of perflubron emulsion on the microcirculation after acute normovolemic hemodilution (ANH) were investigated using different colloid plasma expanders. The dorsal skin fold chamber model and intravital fluorescence microscopy were used for analysis of the microcirculation in the thin striated skin muscle of conscious hamsters (body weight, 40-60 g). Measurements of microvascular perfusion and leukocyte adhesion (n = 6 animals per experimental group) were made before and at 10, 30, and 60 min after ANH (to hematocrit 0.3) with either 6% hydroxyethyl starch 200/0.6 (HES), 3.5% gelatin, 5% human serum albumin (HSA), or 6% dextran 60 (DX-60) followed by intravenous injection of 3 ml/kg body weight of a 60% weight/volume perfluorocarbon emulsion based on perflubron (perfluorooctyl bromide) emulsified with egg yolk lecithin. Acute normovolemic hemodilution with HES, gelatin, or HSA followed by injection of perflubron emulsion elicited no alterations of local microvascular perfusion or leukocyte-endothelium interaction as assessed in arterioles and postcapillary venules. However, ANH with DX-60 followed by injection of perflubron emulsion led to a significant reduction of erythrocyte velocity in postcapillary venules and an increase in venular leukocyte sticking that was never observed with DX-60 alone. Hydroxyethyl starch, gelatin, and HSA are compatible with perflubron emulsion in the setting of ANH. Only DX-60 appeared to be incompatible with perflubron emulsion, as evidenced by impairment of capillary perfusion.

Autologous Blood Predonation Versus Acute Normovolemic Hemodilution

SUMMARY Autologous blood donation is a standard of care for elective surgical procedures requiring blood transfusion. Preoperative autologous blood donation (PAD) and acute normovolemic hemodilution (ANH) are both recommended autologous blood procurement strategies that reduce the need for allogeneic blood transfusions. Limitations of PAD include a high wastage of donated blood and poor cost-effectiveness. In addition, this technique promotes preoperative anemia and a liberal transfusion policy. ANH is a “point-of-care” strategy that can be performed in the operating room, thereby decreasing the cost and wastage of blood. Clinical studies have demonstrated that PAD and ANH have similar efficacy and outcomes in urologic surgery. However, studies comparing these techniques in orthopedic surgery are equivocal. Cost comparisons have demonstrated that ANH is a less costly blood procurement technique than PAD. Additional clinical trials are necessary to further define the role for these autologous blood conservation modalities.

Kostenanalyse autologer Transfusionsverfahren - eine Untersuchung bei 5017 Patienten

Cost analysis of autologous blood conservation measures compared to corresponding homologous blood products. This study is based on data from 5,017 patients undergoing major bone and joint surgery in 1993 and participating preoperatively in autologous blood donation (ABD) (with hemoseparation (HS) into autologous packed red blood cells (APRBC) and autologous fresh-frozen-plasma (AFFP)), autologous plasmapheresis (APPH) for harvesting AFFP as well as intra-/postoperative blood salvage with mechanically processed autologous transfusion (MAT). Total costs for 3,110 ABD with HS amount to DM 517,586.00 resulting in about DM 167.00 per U of APRBC plus AFFP. Comparatively, costs per U of HPRBC is about DM 202.00. Break-even-point (BEP) is calculated with 2,258 U of APRBC (without considering AFFP additionally obtained by HS). Taking into account this AFFP due to coagulation in 20% lowers BEP to 1,819 U of APRBC. However, this analysis compares the "mere" cost figures only, but does not consider the extent of ABD-induced increase in rbc mass compared to that of HPRBC. Under these circumstances calculated cost per unit of APRBC is up to 90 per cent higher than for 1 U of HPRBC. Total cost for PPH with 15,570 U of AFFP amounts to about DM 1,824,162.00, resulting in about DM 115.00 per U of AFFP. Comparatively, cost per U of HFFP is about DM 136.00. BEP is calculated with 11,595 U of AFFP. However, when considering AFFP on coagulatory reasons' with 20% only, no BEP can be calculated and AFFP is not proven to be cost-efficient. Under these conditions it is about 2.8-times more expensive than HFFP; and if considering AFFP a volume substitute it is even more than twelve times more expensive than artificial colloids (e.g. HES 6%, 200/0.5). MAT--2,690 sets and patients with a total of 5,326 processing cycles--causes a total cost of about DM 1,356,161.00, resulting in about DM 504.00 per set and patient. Under our conditions MAT is not cost-efficient compared to HPRBC as it is about two times more expensive than HPRBC. For reaching cost efficiency the number of processing cycles is either to be increased from about 2 to about 4 cycles per set and patient or hematocrit of the rbc-product obtained by MAT is clearly to be increased. The "mere" figures of this cost analysis of APRBC versus HPRBC as well as of AFFP versus HFFP and HES appear in favour of the autologous products. However, such an analysis should consider--besides the costs--both the increase in rbc-mass obtained by ABD or MAT, versus homologous rbc, and the indication for administering AFFP. This study does not prove our autologous blood conservation measures to be cost efficient compared to homologous blood products. Therefore, these data may cause a critically reflection on established concepts of autologous transfusion measures and may initiate promoting new and more cost efficient constellations/alternatives of blood conservation measures.

Changing transfusion practices in hip and knee arthroplasty.

This study was designed to examine changes in perioperative transfusion practices after the introduction of autologous blood conservation strategies into routine clinical practice. The existing medical records of all patients undergoing total hip or knee arthroplasty at Mayo Clinic in Rochester, MN, who resided in Olmsted County, were reviewed over three periods: 1981-82 (232 procedures), 1987-88 (269 procedures), and 1993-94 (398 procedures). The proportion of patients receiving any perioperative red cell (RBC) units significantly decreased (from 85% in 1981-82 to 65% in 1993-94). The timing of transfusion also changed; the proportion of RBC units transfused in the preoperative or intraoperative periods decreased from 68 percent in 1981-82 to 38 percent in 1993-94, with the balance of RBC units transfused in the postoperative period. Although the number of RBC units utilized per procedure in the intraoperative period significantly decreased, the number of RBC units transfused in the postoperative period significantly increased (from 0.6 +/- 1.0 to 1.1 +/- 1.4 units per procedure in 1981-82 and 1993-94, respectively, p < 0.05). Although blood conservation strategies have been successful in reducing RBC transfusion intraoperatively, avoidance of intraoperative transfusion may in some cases postpone, rather than prevent, transfusion.

Acute Normovolemic Hemodilution Versus Predonation

Acute Normovolemic Hemodilution Versus Predonation

Plateletpheresis before redo CABG diminishes excessive blood transfusion

Blood conservation remains an important element for patients undergoing cardiac operations with cardiopulmonary bypass. Preoperative platelet-rich plasma (PRP) harvest is an autologous blood conservation method. The efficacy of preoperative PRP harvest and post-cardiopulmonary bypass reinfusion on postoperative bleeding and need for postoperative blood transfusion was evaluated in patients undergoing redo coronary artery bypass grafting in a prospective, randomized manner. All adult patients admitted for redo coronary artery bypass grafting entered into the study. The PRP harvest aim was 20% or more of the total estimated circulating platelets. Immediately preoperatively three sequestration cycles were performed. The PRP was reinfused after weaning from cardiopulmonary bypass. One hundred seven parameters/patient were recorded. There were 20 patients in the RPR group and 20 controls (without PRP harvest). Patient characteristics, operative data, and preoperative hematologic parameters did not differ between the groups. In the PRP group, the mean platelet count in the PRP was 864 +/- 139 x 10(3)/microL, and the platelet yield was 27% +/- 5% (range, 20% to 37%). The average total chest tube blood loss was 423 mL (PRP) compared with 1,462 mL (controls; p < 0.001). Fourteen patients in the control group required blood transfusions postoperatively compared with only 1 patient in the PRP group (p < 0.001). Postoperative fluid requirements were also significantly greater in the control group (p < 0.001). Postextubation gas exchange was significantly better in the PRP group compared with controls (p < 0.01). Postoperative ventilation time and intensive care stay were significantly shorter in patients in the PRP group. A preoperative PRP harvest of 20% or more of the total platelets and reinfusion of the PRP after cardiopulmonary bypass resulted in significantly less postoperative blood loss and decreased fluid and blood transfusion requirements compared with controls. Postextubation gas exchange, ventilation time, and time required in the intensive care unit were also better, and the method was found cost-effective.

Comparison of blood reinfusion techniques used during coronary artery bypass grafting

A comparison of intraoperative autologous blood conservation techniques was carried out in 100 patients undergoing coronary artery bypass grafting. To facilitate comparisons of similar groups, patients were stratified into high-risk and low-risk groups based on the ratio of preoperative bleeding time to preoperative red blood cell volume. Our previous work suggested that patients with an elevated ratio have increased risk of excessive postoperative blood transfusion. We used this ratio to stratify the 100 patients to either the high-risk (39 patients) or low-risk (61 patients) strata. Within each stratum, patients were randomized to one of three groups: no intraoperative autologous blood conservation (control group), infusion of autologous platelet-rich plasma obtained from intraoperative plasmapheresis (PRP group), and infusion of autologous whole blood harvested immediately before cardiopulmonary bypass (whole blood group). Variables of postoperative blood loss and transfusion requirements were measured in each patient. Analysis of variance showed significant differences in blood product transfusions between groups. Patients in the high-risk stratum required significantly more blood product transfusions than those in the low-risk stratum (5.4 ± 0.7 versus 2.0 ± 0.6 units per patient; p < 0.001). In the high-risk stratum, PRP patients required significantly less postoperative blood transfusion compared with patients in the high-risk control group (2.9 ± 2.1 versus 8.1 ± 2.2 units per patient; p = 0.05). In the low-risk stratum, no intraoperative blood infusion method resulted in significant improvement in postoperative blood use. We conclude that intraoperative autologous blood reinfusion methods are not helpful in low-risk patients but, for high-risk patients, infusion of autologous PRP is associated with significantly less postoperative blood transfusion. This suggests that the added cost of intraoperative autologous blood conservation techniques is justified in patients at high risk for excessive postoperative blood transfusion but not in patients at low risk.

Plasmapheresis Techniques During Cardiac Surgery

Plasmapheresis is an aggressive autologous blood conservation method utilized in cardiac surgery to reduce patient exposure to homologous blood transfusion. Presently the three perioperative techniques which have been used clinically incorporate varying methodology in producing platelet rich plasma (PRP). However, no prospective randomized study has been made to concurrently examine the benefits of individual devices. Fifty-two consenting adult cardiac patients who met selection criteria were randomly assigned to one of three plasmapheresis devices: Plasma Saver (PS), Cell Saver (CS), and Autotrans 1000 (AT 1000). Following induction of anesthesia, 20% of each patient's estimated plasma volume was removed, stored and then reinfused following the reversal of heparin with protamine. One hundred and twenty-two parameters were measured for each patient. These included anthropomorphic, operative, cardiopulmonary bypass, and postoperative follow-up parameters. Indices of hemostasis were measured which included coagulation screens and thrombelastographic data. There were no differences between groups in all preoperative parameters including the volume of PRP removed. Fibrinogen levels in the PRP were 213.9 +/- 63, 219.4+/-73, and 188.9+/- 69mg/dl in groups PS,CS, and AT 1000 (p=NS), while platelet counts were 178.4 +/- 73, 121.6 +/- 85, and 210.6 +/- 77 109/L, respectively (p&lt;.05 CS vs. AT). There were no differences in chest tube drainage, time on ventilator, or length of ICU stay between groups. However, patients in PS group had significantly lower discharge platelet counts than groups CS and AT 1000. Total homologous blood exposure rate (donor blood exposure per patient) was 8.2 units in group PS, 4.5 in CS, and 5.4 in AT 1000, (p=NS). The currently available techniques for perioperative PRP production differ in both methodology and platelet yield, although the difference did not result in significantly different patient postoperative outcome indices.

Total Autologous Blood Conservation Achieved by One Machine Using One Operator

Total Autologous Blood Conservation Achieved by One Machine Using One Operator