Unwashed Shed Blood Research Articles

Cell Salvage at the ICU.

Patient Blood Management (PBM) is a patient-centered, systemic and evidence-based approach. Its target is to manage and to preserve the patient’s own blood. The aim of PBM is to improve patient safety. As indicated by several meta-analyses in a systematic literature search, the cell salvage technique is an efficient method to reduce the demand for allogeneic banked blood. Therefore, cell salvage is an important tool in PBM. Cell salvage is widely used in orthopedic-, trauma-, cardiac-, vascular and transplant surgery. Especially in cases of severe bleeding cell salvage adds significant value for blood supply. In cardiac and orthopedic surgery, the postoperative use for selected patients at the intensive care unit is feasible and can be implemented well in practice. Since the retransfusion of unwashed shed blood should be avoided due to multiple side effects and low quality, cell salvage can be used to reduce postoperative anemia with autologous blood of high quality. Implementing quality management, compliance with hygienic standards as well as training and education of staff, it is a cost-efficient method to reduce allogeneic blood transfusion. The following article will discuss the possibilities, legal aspects, implementation and costs of using cell salvage devices in an intensive care unit.

Cell salvage : Scientific evidence, clinical practice and legal framework

Cell salvage is an efficient method to reduce the transfusion of homologous banked blood, as documented by several meta-analyses detected in a systematic literature search. Cell salvage is widely used in orthopedics, trauma surgery, cardiovascular and abdominal transplantation surgery. The retransfusion of unwashed shed blood from wounds or drainage is not permitted according to German regulations. Following irradiation of wound blood, salvaged blood can also be used in tumor surgery. Cell salvage makes avaluable contribution to providing sufficient compatible blood for transfusions in cases of massive blood loss. Certain surgical procedures for Jehovah's Witnesses are only possible with the use of cell salvage. Another possible use is the washing of homologous banked blood, e. g. to prevent potassium-induced arrhythmia or sequestration of autologous platelets. Other advantages besides agood compatibility are the high vitality and functionality of the unstored autologous red blood cells. These have been declared apharmaceutical product by the German transfusion task force in 2014, so that the autologous red blood cells are now under the control of the Pharmaceutical Products Act (AMG). The new hemotherapy guidelines, however, tolerate cell salvage only under strict rules, whereby the production of autologous blood during or after surgery is still possible without additional special permits. The new guidelines now require the introduction of aquality management system for cell salvage and regular quality controls. These quality controls include acontrol of the product hematocrit for every application, monthly controls of the protein and albumin elimination rates and the erythrocyte recovery rate for each cell salvage device. Testing for infection markers is not required. The application of cell salvage has to be reported to the appropriate authorities.

Low vacuum re-infusion drains after total knee arthroplasty: is there a real benefit?

Low vacuum re-infusion drains after total knee arthroplasty: is there a real benefit?

Disminución de las transfusiones alogénicas por la generalización del uso de recuperadores de sangre postoperatorios en cirugía de prótesis de rodilla

ObjectivesSurgical teams have several tools in order to reduce the need for postoperative allogenic transfusion. Postoperative autotransfusion of unwashed shed blood has become common practice for total knee replacement surgery since 2006 in our hospital. This study was designed to evaluate if this practice has reduced allogenic blood transfusions. Material and methodsA retrospective study comparing two cohorts, group 2004 with patients operated on for total knee replacement during the year 2004, before the use of the retransfusion system, and group 2008, patients operated on in the year 2008, with regular use of the retransfusion system. Gender, preoperative and postoperative haemoglobin levels, total amount of calculated erythrocytes lost, reinfusion of shed blood and allogenic blood transfusion during hospital stay were recorded. ResultsBoth groups were similar as regards gender, preoperative and postoperative hemoglobin levels, and total amount of erythrocytes lost. The proportion of transfused patients was significantly lower in group 2008 versus group 2004 (20.18% versus 42.19%), with a relative risk of being transfused of 0.47 and a NNT of 4.54. P=.0017. ConclusionsIn our hospital the use of postoperative retransfusion systems has reduced the proportion of transfused patients during hospitalization for total knee replacement surgery, although this result cannot be generalized due to the lack of a fixed transfusion trigger.

Does Single Use of an Autologous Transfusion System in TKA Reduce the Need for Allogenic Blood?: A Prospective Randomized Trial

Mechanical autotransfusion systems for washed shed blood (WSB) were introduced to reduce the need for postoperative allogenic blood transfusions (ABTs). Although some authors have postulated decreased requirements for ABT by using autologous retransfusion devices, other trials, mostly evaluating retransfusion devices for unwashed shed blood (USB), verified a small or no benefit in reducing the need for postoperative ABT. Because of these contradictory findings it is still unclear whether autologous retransfusion systems for WSB can reduce transfusion requirements. We therefore asked whether one such autologous transfusion system for WSB can reduce the requirements for postoperative ABT. In a prospective, randomized, controlled study, we enrolled 151 patients undergoing TKA. In Group A (n=76 patients), the autotransfusion system was used for a total of 6 hours (intraoperatively and postoperatively) and the WSB was retransfused after processing. In Control Group B (n=75 patients), a regular drain without suction was used. We used signs of anemia and/or a hemoglobin value less than 8 g/dL as indications for transfusion. If necessary, we administered one or two units of allogenic blood. Twenty-three patients (33%) in Group A, who received an average of 283 mL (range, 160-406 mL) of salvaged blood, needed a mean of 2.1 units of allogenic blood, compared with 23 patients (33%) in Control Group B who needed a mean of 2.1 units of allogenic blood. We found the use of an autotransfusion system did not reduce the rate of postoperative ABTs. Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Blood transfusion and cytokines’ changes in total knee replacement

The aim of this prospective comparative study was to evaluate the serum levels of different cytokines and the frequency of adverse reactions and wound infections in patients who underwent total knee replacement (TKR) and were not transfused or received either allogeneic blood transfusion or postoperative auto-transfusion (PAT) with unwashed shed blood. A total of 248 patients were categorized into three groups; in Group 0 (n 85) patients received no blood transfusion, in Group 1 (n 92) patients received PAT and in Group 2 (n 71) patients received allogeneic blood transfusion. Patient's demographic and clinical data including age, gender, body mass index, preoperative haemoglobin value, adverse reactions and complications were documented. The serum levels of IL-1b, IL-6, IL-8, IL-10 and TNF were measured preoperatively, and on the first, third and fifth postoperative day. A statistical analysis of the results was performed. A significant elevation of cytokine values were observed during the first five postoperative days in patients who received blood transfusion after TKR. Adverse reactions (chills and pyrexia) were also more common in patients who received blood transfusion, whereas superficial infections were more common in patients who received allogeneic blood transfusion. The immunological status-as expressed by the measured cytokine levels-is altered in patients receiving blood transfusion compared to patients receiving no blood transfusion during the first five postoperative days. PAT is preferable to allogeneic blood transfusion in terms of the rate of adverse reactions and superficial wound infections.

A cost study of postoperative cell salvage in the setting of elective primary hip and knee arthroplasty

The increasing costs, limited supply, and clinical risks associated with allogeneic blood transfusion have prompted investigation into autologous blood management strategies, such as postoperative red blood cell (RBC) salvage. This study provides a cost comparison of transfusing washed postoperatively salvaged RBCs using an orthopedic perioperative autotransfusion device (OrthoPat, Haemonetics Corporation) versus unwashed shed blood and banked allogeneic blood. Cell salvage data were retrospectively reviewed for a sample of 392 patients who underwent primary hip or knee arthroplasty. Mean unit costs were calculated for washed salvaged RBCs, equivalent units of unwashed shed blood, and therapeutically equivalent volumes of allogeneic RBCs. No initial capital investment was required for the establishment of the postoperative cell salvage program. For patients undergoing total knee arthroplasty (TKA), the mean unit costs for washed postoperatively salvaged cells, unwashed shed blood, and allogeneic banked blood were $758.80, $474.95, and $765.49, respectively. In patients undergoing total hip arthroplasty (THA), the mean unit costs for washed postoperatively salvaged cells, unwashed shed blood, and allogeneic banked blood were $1827.41, $1167.41, and $2609.44, respectively. This analysis suggests that transfusing washed postoperatively salvaged cells using the OrthoPat device is more costly than using unwashed shed blood in both THA and TKA. When compared to allogeneic transfusion, washed postoperatively salvaged cells carry a comparable cost in TKA, but potentially represent a significant savings in patients undergoing THA. Sensitivity analysis suggests that in the case of TKA, however, cost comparability exists within a narrow range of units collected and infused.

Sedimentation method for preparation of postoperatively salvaged unwashed shed blood in orthopaedic surgery

BackgroundSalvage and return of unwashed shed blood (USB) after total knee replacement (TKR) is an established blood-saving technique, but some authors question its efficacy and safety and suggest that the shed blood be washed before returning. We evaluated a colloid-based sedimentation method for improving and standardizing the quality of USB collected after TKR without the need for washing. MethodsExperiments were performed to find the optimal colloid dose and sedimentation time using diluted donated venous blood. USB samples (n=52) were drawn from the reinfusion bag and mixed with hydroxyethyl starch or gelatine solutions (15−30%, colloid solution volume/total volume×100). USB red blood cells (RBCs) were allowed to settle by gravity for 30 min, supernatant was evacuated from the syringe, and RBC concentrate was analysed. RBC recovery and other blood cell and chemical removal were calculated according to changes in USB volume and haematocrit. Twenty-five samples from leucodepleted packed RBCs were analysed as a comparator group. ResultsMean haemoglobin (Hb) of USB was 10.9 g dl−1. After colloid treatment, 90% of RBCs were recovered, and USB Hb was similar to that of leucodepleted packed RBCs (n=25) (18.9 vs 19.6 g dl−1, respectively; P=NS). In addition, the procedure reduced USB content of leucocytes (60%), platelets (48%), total protein (76%), cytokines (70–77%), and plasma-free haemoglobin (53%), without major differences between colloids. ConclusionsSedimentation of USB with colloid solutions provides a low-cost alternative for improving and standardizing the quality of salvaged USB after TKR.

Tranexamic acid for reducing transfusion requirements after total knee arthroplasty: can efficacy and cost ratios be improved?

We read with interest the large study on the use of tranexamic acid (TA) in 414 consecutive patients undergoing total knee arthroplasty (TKA) published by Lozano et al . in Vox Sanguinis [1]. The authors showed that the routine use of TA administration in the management of TKA was associated with significant reduction in allogeneic blood transfusion (ABT) rate and blood management costs [1]. More importantly, this study, which encompassed the largest number of patients reported so far, showed that TA did not seem to be associated with an increased rate of thromboembolic complications [6/215 (2·4%) vs. 3/199 (1·5%), for control and TA groups, respectively; P = 0·507]. We would like, however, to comment regarding data of efficacy and costs. First, the ABT rate in the control group (54%) is significantly higher than that observed in two recent series of TKA patients with similar age, gender distribution and preoperative haemoglobin (30%), and the same is true for patients receiving TA when compared to those receiving postoperative unwashed shed blood (USB, 0·78 ± 0·52 units per patient) or preoperative treatment with oral iron [2,3] (Table 1). One possible reason for these differences may the use of high vacuum drains (650 mmHg), which resulted in a higher estimated blood loss (2325 ± 1196 ml and 1592 ± 823 ml, for control and TA, respectively) [1], when compared to a similar study using low vacuum drains (100 mmHg; 1744 ± 804 ml and 1301 ± 621 ml, respectively) [4]. In this later study, the use of low vacuum drains with reinfusion resulted in an ABT rate of 12·2% (6/49), which was decreased to 2·2% (1/46) by its combination with TA [4]. Second, in their economical analysis, the official price of a red blood cell (RBC) unit in Catalonia, Spain ( a 97·63), was used [1]. However, this so-called ‘official price’ is indeed a ‘political price’ for blood interchange between autonomic communities within Spain, and it does not correspond to the actual production costs of a RBC unit. In addition, the costs of pre-transfusion tests and giving set were also not included. Therefore, in agreement with average cost within the European Union, we estimated an actual cost of a 320 for one RBC transfusion in Spain [5]. Using this figure, the use of TA in TKA reduced transfusion cost per patient to a 108 (Table 1), which favourably compared to the cost of a 177 per patient for USB return ( a 120 per USB collection device) [2], but not with that of preoperative oral iron plus restrictive transfusion protocol ( a 46 per patient) [3]. All together, these results

Research on Coagulation of Unwashed Shed Blood After Total Knee Replacement in Chinese Patients

To evaluate quality of unwashed but filtered wound shed blood through ConstaVac blood conservation system (Stryker Company) after total knee replacement, we selected 30 patients who underwent total knee replacement consecutively from July 2003 to July 2004 and received retransfusion of wound shed blood. Pre- and postoperative coagulative factors of peripheral vein blood and wound shed blood were measured, such as fibrinogen, AT-III, D-dimer, plasminogen, and PT, APTT were also measured. No clinical evidence of coagulation and DIC appeared in these patients. There is significant change of coagulative factors in unwashed but filtered wound shed blood and it may cause a potential risk of coagulopathy to retransfuse wound shed blood, but retransfusion of unwashed but filtered shed blood appeared to be relative safe clinically.

Cell Salvage Alters the Systemic Inflammatory Response After Off-Pump Coronary Artery Bypass Grafting Surgery

Retransfused cardiotomy suction blood contains elevated inflammatory markers and is a bypass independent source of inflammatory mediators. We hypothesized that, during off-pump coronary artery bypass (OPCAB) grafting surgery, avoiding retransfusion of unwashed cardiotomy suction blood would beneficially alter both urinary and plasma cytokine concentrations and be renoprotective. Thirty-seven OPCAB surgery patients were randomly allocated to control (retransfusion of unwashed shed blood) and treatment (retransfusion of washed shed blood or discarding of unwashed blood) groups. Over 72 hours we measured plasma (tumor necrosis factor-alpha [TNF-alpha], interleukin-8, interleukin-6, interleukin-10, TNF soluble receptor-2, and interleukin-1 receptor antagonist) and urinary TNF soluble receptor-2 and interleukin-1 receptor antagonist and markers of renal injury and dysfunction (N-acetyl beta D glucosaminidase and alpha1-microglobulin). We demonstrated elevated proinflammatory cytokines in cardiotomy suction blood, which were effectively eliminated by cell salvage. After retransfusion, in comparison with controls, the treatment group had reduced plasma TNF soluble receptor-2. As compared with controls, treatment group patients also demonstrated significantly reduced levels of the urinary anti-inflammatory cytokine TNF soluble receptor-2. There were no between group differences in markers of renal injury or dysfunction. We have demonstrated that the management of shed mediastinal blood alters perioperative, systemic, plasma and urinary cytokine homeostasis at OPCAB surgery but does not impact on subclinical renal injury or dysfunction in this low risk group of patients.

Perioperative intravenous iron, with or without erythropoietin, plus restrictive transfusion protocol reduce the need for allogeneic blood after knee replacement surgery

Unilateral total knee replacement (TKR) results in a substantial blood loss and 30 to 50 percent of patients receive allogeneic blood transfusion (ABT). Therefore, the effectiveness of a restrictive transfusion trigger (hemoglobin [Hb] level < 8 g/dL) plus stimulation of erythropoiesis was evaluated, with or without blood salvage, for reducing ABT in TKR patients. A series of 139 consecutive of primary TKR patients received perioperative iron sucrose (2 x 200 mg/48 hr, intravenously [IV]), plus preoperative erythropoietin (EPO; 1 x 40.000 UI, sc) if preoperative Hb level was less than 130 g per L (Group A). This protocol was applied to another series of 173 consecutive TKR patients who also received postoperative unwashed shed blood (USB) if preoperative Hb level was less than 130 g per L (Group B). Perioperative clinical and laboratory data were gathered. No adverse effects of iron sucrose, EPO, or USB administration were witnessed, and only 13 patients received ABT overall (4%). No major differences in perioperative blood counts or iron metabolism variables were observed between groups, but stimulation of erythropoiesis seemed to be more pronounced in those patients receiving EPO (p < 0.05). There were no differences in postoperative complications between groups, but length of hospital stay for patients with a preoperative Hb level of less than 130 g per L was shorter in Group B (p < 0.05). This blood saving protocol seems to be effective for reducing ABT in TKR patients. Which patients are more likely to benefit from either perioperative iron administration or selective addition of postoperative blood salvage to pharmacologic treatment, however, needs to be further evaluated.

Coagulation Parameters After Retransfusion of Unwashed Blood

Postoperative blood salvage reduces the risk of allogenic transfusion in patients undergoing elective total joint arthroplasty. We measured the concentrations of coagulation parameters after autotransfusion of unwashed shed blood in 22 patients having elective joint arthroplasty and compared them with patients without retransfusion. Twenty-two patients with a total hip or knee arthroplasty received a mean of 611.4 mL unwashed but filtered shed blood. No complications were observed during or after the reinfusion of salvaged blood. Levels of D-dimer and fibrinogen increased significantly over time after retransfusion ( P < .0001). Comparison of the autotransfused group with the 25 patients without reinfused shed blood showed no significant difference in fibrinogen concentration between the 2 groups in the postoperative course but a significant difference with increased D-dimer concentrations in the autotransfused group ( P < .001).

Post‐operative unwashed shed blood transfusion does not modify the cellular immune response to surgery for total knee replacement

In patients undergoing total knee replacement (TKR), most blood loss occurs post-operatively, and the return of unwashed filtered shed blood (USB) from post-operative drainage may represent an alternative to allogeneic blood transfusion (ABT). We evaluated the impact of USB return on the cellular immune response (CIR) after TKR. Forty TKR patients, intended to receive post-operative USB, entered the study. Blood samples were obtained before and 6 h, 24 h, 72 h and 7 days after surgery, and from USB, after it had been passed through a 40-microm filter. Full blood cell counts, lymphocyte subsets and immunoglobulins (IgA, IgG, IgM) were measured in all samples. A set of clinical data was collected from each patient. Twenty-four of the 25 patients received a mean of 1.2 USB units and did not need additional ABT (USB group). Twelve of the 15 remaining patients who received neither USB nor ABT served as a control group for the post-operative CIR study. All patients showed a post-operative decrease in T-cell and natural killer (NK) cell counts, but not B-cell counts, and there were no significant differences between the groups with regard to CIR parameters, post-operative infection or hospital stay. Post-operative salvage and return of USB after TKR does not seem to increase the post-operative infection rate or hospital stay, and does not modify CIR induced by surgery. These findings add to the clinical experience that post-operative USB return, as a source of autologous blood, is safe, and questions the beneficial effect of blood washing.

Impact of Postoperative Unwashed Shed Blood Retrieved after Total Knee Arthroplasty on Endotoxin-stimulated Tumor Necrosis Factor α Release In Vitro

: Allogeneic or autologous blood seems to have an immunosuppressive effect that is largely attributable to storage-dependent factors. However, transfusion of postoperative unwashed shed blood (USB) after elective total knee replacement does not undergo storage. Therefore, the authors explored the effects of USB on the mitogen-driven cytokine synthesis by the patient's peripheral blood mononuclear cells. : Perioperative blood samples were obtained from 12 total knee replacement patients with and 5 without reinfusion of leukoreduced USB, and from USB reinfusion line, before and after leukoreduction. Venous blood obtained at 4-6 postoperative hours was coincubated with USB. Endotoxin-stimulated release of tumor necrosis factor alpha and interleukin 10 was measured after 24 h of culture by solid-phase enzyme-labeled chemiluminescent immunometric assay. : Coincubation of postoperative venous blood with USB, USB cells, or USB plasma resulted in a significant depression of tumor necrosis factor-alpha synthesis, without significant effects on interleukin-10 synthesis. However, no differences were observed for endotoxin-stimulated cytokine release in perioperative blood samples from patients receiving or not receiving USB. : These data suggest that USB seemed to contain an antiinflammatory agent. However, at the actual retransfusion rate, USB does not seem to further enhance the immunosuppression that follows knee replacement surgery.

Transfusion of post-operative shed blood: laboratory characteristics and clinical utility.

Increased awareness of the potential hazards of allogenic blood transfusion, such as incompatibility reactions, metabolic and immunologic disorders, or transmission of viral diseases, has led to an emphasis on allogeneic blood alternatives. For orthopaedic surgery, several autologous transfusion modalities have emerged as alternatives to allogeneic blood transfusion, avoiding its immunomodulatory effects. Among them, transfusion or return of post-operative salvaged shed blood has become popular in major orthopaedic procedures. However, although the effectiveness of this blood-saving method is well documented, several authors have questioned its safety and recommended the use of washed blood. Therefore, this review analyses the haematologic characteristics of unwashed filtered shed blood, including metabolic status and survival of red blood cells, the components of the haemostatic system, the content of fat particles, bacterial and tumour cells and the possibility of their removal, the content of inflammatory mediators, and the effects on the patient's immune system. From data reviewed in this paper, it can be concluded that post-operative salvage of blood seems to be an excellent source of functional and viable red cells without many of the transfusion-related risks and with some immuno-stimulatory effects. In addition, from our experience, post-operative re-infusion of unwashed shed blood after major spine procedures has proved to reduce post-operative homologous transfusion requirements and to complement pre-operative autologous blood donation, without any clinically relevant complication.

Clinical result of unwashed shed blood transfusion after TKA

Clinical result of unwashed shed blood transfusion after TKA

Cell washing versus immediate reinfusion of intraoperatively shed blood during abdominal aortic aneurysm repair

Significant hematologic changes are known to occur following intraoperative autotransfusion of shed blood, but the clinical importance of cell washing prior to reinfusion has not been substantiated. To evaluate these changes and their relationship to the use of blood bank products and postoperative morbidity, 26 patients undergoing elective abdominal aortic aneurysm repair were prospectively randomized to reinfusion with washed shed blood or to the use of a collection system in which filtered, but unwashed, whole blood was reinfused intraoperatively. Each patient was evaluated with respect to standard metabolic and hematologic laboratory parameters preoperatively, immediately postoperatively, and 12 to 18 hours postoperatively. Patient demographic data were similar for both groups. Perioperative survival was 100% for both groups. Total blood loss and blood volume autotransfused were significantly greater in the unwashed cell group compared with the washed cell group (p = 0.00014 and p = 0.00011, respectively). Hemoglobin, fibrinogen, prothrombin time, and partial thromboplastin time levels were not significantly different between the two groups at any time perioperatively; fibrin split product and d-dimer levels were significantly higher in the unwashed cell group postoperatively (p = 0.016 and p < 0.001, respectively). Serum free hemoglobin levels were significantly higher in the immediate postoperative period in the unwashed cell group compared with the washed cell group (p = 0.0013); by 12 to 18 hours postoperatively, this difference was not significant. Haptoglobin levels were significantly lower in the unwashed cell group at both postoperative times (123 +/- 86 mg/dL versus 41 +/- 50 mg/dL, p = 0.0086; 102 +/- 66 mg/dL versus 24 +/- 36 mg/dL, p = 0.0001); however, there was no perioperative renal failure in either group. Furthermore, homologous blood product use was not significantly different between the two groups, with an average of 1.5 +/- 2.5 units of packed red blood cells given to patients in the unwashed cell group versus 0.8 +/- 1.7 units in the washed cell group (p = 0.419). Overall complications were higher and critical care and total hospital stays were longer in the unwashed cell group but did not result from autotransfusion of unwashed blood. We conclude that the intraoperative reinfusion of unwashed shed blood is safe and effective, causing transient hematologic abnormalities that normalize in the early postoperative period, and is not associated with increased mortality, or hematologic, cardiopulmonary, or renal complications.

Autotransfusion of unwashed mediastinal shed blood fails to decrease banked blood requirements in patients undergoing aortocoronary bypass surgery

Infusion of unwashed mediastinal shed blood (MSB) is one technique advocated for decreasing use of donor blood in cardiac surgery patients. A commercially available system was prospectively evaluated in 96 consecutive patients. The control group was comprised of 78 consecutive patients. All underwent elective aortocoronary bypass surgery. Student's t-test, chi-square analysis, multivariate analysis, and Fisher's exact test were used where appropriate. There was no decrease in the amount of banked blood required or percentage of patients who received transfusions in the MSB autotransfusion group.

Unwashed filtered shed blood collected after knee and hip arthroplasties. A source of autologous red blood cells.

We evaluated the results of twelve hematological and plasma protein determinations in 450 to 500-milliliter volumes of shed blood that had been collected with or without acid-citrate-dextrose anticoagulant (National Institutes of Health Formula A) from knees and hips during the first twelve hours after arthroplasty. We also evaluated the effects on the recipients when the blood was used for reinfusion. The findings in the units that had been obtained in less than four hours, in between four and six hours, and in more than six hours after the arthroplasty were similar whether or not the acid-citrate-dextrose anticoagulant had been used. The mean values for the collected units were: in the blood, a concentration of hemoglobin of 115 grams per liter, a hematocrit of 0.34, a white blood-cell count of 4.8 x 10(9) per liter, and a red blood-cell count of 3.7 x 10(12) per liter, and, in the plasma, a level of hemoglobin of 160 grams per liter, a level of fibrinogen of less than 0.2 gram per liter, a level of factor-V clotting protein of less than 10 per cent of normal, a level of factor-VIII clotting protein that was 45 per cent of normal, a level of antithrombin III that was 45 per cent of normal, a level of plasminogen that was 55 per cent of normal, a level of protein C that was 100 per cent of normal, and a level of fibrin-degradation products of 1000 micrograms per milliliter of plasma. The clinical response of the patient was assessed after the reinfusion of a total of 205 units of unwashed shed blood into 153 patients. In addition, in 126 of the 153 patients, hematological and plasma-protein measurements were analyzed before the autotransfusion and one and twenty-four hours afterward. Each of these patients had received one to four units of shed blood that had been filtered but not washed. Only two (2 per cent) of the ninety-nine patients who received shed blood that had been collected six hours or less after the operation had a febrile reaction, whereas twelve (22 per cent) of the fifty-four patients who received blood that had been collected six to twelve hours after the operation had such a reaction.(ABSTRACT TRUNCATED AT 400 WORDS)