The risks of blood transfusion: the relative influence of acquired immunodeficiency syndrome and non-A, non-B hepatitis

Le Domaine Privé de la Santé Publique Pouvoir, politique et sida au Congo

L'histoire du gouvernement des conduites humaines en matière d'hygiène et de reproduction, et plus généralement l'étude des relations entre santé, sexualité et politique sont au centre des derniers travaux de Michel Foucault. Analysant parallèlement la mise en pratique des biopolitiques et la mise en discours du sexe dans les sociétés occidentales, il montre d'une part, comment l'autorité publique déploie une activité croissante dans la gestion des affaires privées des personnes alors même que se développe l'idéologie libérale, et d'autre part, comment la médecine, se réclamant de la vérité scientifique, entreprend de rationaliser et de normaliser les comportements, tant dans le domaine de la santé que dans celui de la sexualité.

An economic analysis of costs associated with development of a cell salvage program

BACKGROUND

The increasing cost of blood products and associated risks of transfusion have lead to a heightened interest in techniques which reduce or replace allogeneic blood transfusion. The use of cell salvage is being explored in a number of institutions. We present financial information which may be useful to institutions that are considering the addition of a cell salvage service.

METHODS

A review of the cell salvage data from 2328 patients was used to estimate the average cost of a packed red blood cell unit equivalent processed by cell salvage equipment. In addition, an analysis was performed to assess the break-even point of establishing a cell salvage service.

RESULTS

Initial capital outlay to establish a cell salvage service at this institution was $103,551. The annual fixed operating cost was $250,943. The average cost of transfusion of an allogeneic packed red blood cell unit was $200. For an equivalent cell salvage unit, the cost was $89.46. The payback period was 1.9 mo.

CONCLUSION

This analysis suggests that cell salvage can be significantly less expensive than allogeneic blood. The cost of cell salvage in other institutions will vary depending upon case volume, expected levels of blood loss per case, and initial investment costs. A step-by-step formula is provided to assist in the evaluation of a cell salvage service in hospitals of various sizes.

Cell salvage does not minimize perioperative allogeneic blood transfusion in abdominal vascular surgery: a systematic review

PURPOSE

To determine whether the use of cell salvage reduces the proportion of patients receiving at least one unit of allogeneic packed red blood cells during the perioperative period of an elective vascular surgery.

SOURCE

We identified all relevant articles through the combined use of electronic searches of the MEDLINE and EMBASE databases, the Cochrane library as well as hand searching of all randomized clinical trials and review articles. The electronic search included articles published between 1966 and April 2001. The search included textword searches using "autotransfusion," "cell salvage," "device," or Medical Subject Headings "autologous blood transfusion" or a "randomized controlled trials" filter.

PRINCIPAL FINDINGS

Five randomized controlled trials (RCT) were identified involving cell salvage and vascular surgeries. In infra renal abdominal aortic aneurysm surgery the risk ratio (the risk of receiving at least one unit of allogeneic red cells) was 0.37 [95% confidence intervals (CI) of 0.06 to 2.36]. In elective aorto-femoral bypass surgery the risk ratio was 0.97 (95% CI of 0.66 to 1.42). The pooled risk ratio for cell salvage in vascular surgery was 0.67 (95% CI of 0.35 to 1.28).

CONCLUSION

Cell salvage, a commonly used technique to recover red cells from the operative field, has been the subject of several studies in vascular surgery. There is insufficient evidence to recommend the routine use of cell salvage in elective abdominal aortic aneurysm and aorto-femoral bypass surgeries. A large RCT would elucidate whether cell salvage is effective as a blood conservation technique.

The current role of preoperative and intraoperative autologous blood donation in pediatric open-heart surgery

OBJECTIVE

We assessed the current role of preoperative and intraoperative autologous blood donation in pediatric open-heart surgery.

METHODS

Group 1 consisted of 51 patients between 5 and 10 years old who underwent preoperative autologous blood donation. Group 2 consisted of 50 age-matched patients without preoperative donation as controls. Intraoperative donation was conducted in both groups prior to cardiopulmonary bypass. We evaluated perioperative blood cell count, blood loss, and the need for homologous blood products.

RESULTS

No serious complications occurred in preoperative or intraoperative donation. Total preoperative donation storage was 17.5 +/- 3.4 mL/kg. Intraoperative donation was 21.7 +/- 6.1 mL/kg in Group 1 and 12.8 +/- 4.0 mL/kg in Group 2 (p < 0.001). On admission, serum hemoglobin was lower in Group 1 (12.2 +/- 1.0 g/dL versus 13.6 +/- 1.6 g/dL, p < 0.001) but returned postoperatively to the preoperative value. It hovered at a depressed level in Group 2 (12.2 +/- 1.4 versus 10.2 +/- 1.1 g/dL, p < 0.001). The homologous blood requirement was significantly less in Group 1 than in Group 2 (0% versus 10%, p < 0.05). Postoperative platelet counts showed similar curves, and blood loss was not statistically significantly different between groups.

CONCLUSION

Preoperative and intraoperative donations are safe and continue to contribute uniquely to blood conservation, providing important options in comprehensive blood conservation programs in current pediatric open-heart surgery.

The effects of epoetin alfa on transfusion requirements in head and neck cancer patients: a prospective, randomized, placebo-controlled study

OBJECTIVE

To evaluate the efficacy of perioperative recombinant human erythropoietin (r-HuEPO, epoetin alfa) in stimulating hematopoiesis and reducing allogeneic blood transfusion requirements in major head and neck cancer surgery.

STUDY DESIGN

Double-blinded, placebo-controlled, randomized, prospective clinical trial.

METHODS

Fifty-eight patients undergoing surgical resection of head and neck tumors at the University of Iowa hospitals completed this study. Patients were required to have a pre-study hemoglobin >/=10.0 g/dL and </=13.5 g/dL. Group 1 (29 patients) received three doses of 600 IU/kg epoetin alfa before surgery. Group 2 (29 patients) received a placebo. All patients received oral iron supplementation (150 mg FeSO4 twice per day).

RESULTS

The epoetin alfa group demonstrated a significant increase in baseline to day-of-surgery mean hemoglobin (0.57 g/dL, P =.016), hematocrit (2.04%, P =.015), and reticulocyte count (95.3 x 103 cells/mm3, P = <.001), whereas there was no significant change in these hematologic variables in the placebo group. The percent of patients who avoided transfusion in the epoetin alfa group was 34.5% versus 17.2% in the placebo group. Patients requiring allogeneic blood transfusions received an average of 3.16 units in the epoetin alfa group and 4.12 units in the placebo group.

CONCLUSION

In this single institution study, we demonstrated a significant improvement in hematopoietic parameters and a trend toward decreased transfusion requirements using perioperative epoetin alfa in a head and neck cancer patient population. Further studies may delineate additional benefits in treating qualified patients with epoetin alfa during therapy for head and neck malignancies.

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 <or=37% (P<or=.01). Perioperative blood salvage is safe and cost-effective and makes it possible to discontinue the practice of predonating blood for primary total knee arthroplasty and total hip arthroplasty in patients with a preoperative hematocrit >37%.

Autologous blood transfusion in oral and maxillofacial surgery patients with the use of erythropoietin

Background: Autologous blood transfusion presents few infectious or immunologic side effects. The aim of the present study was to determine the impact of autologous blood transfusion with or without recombinant human erythropoietin (rHuEPO) in patients who underwent elective maxillofacial operations. Material: Seventy eight consecutive patients (29 men and 49 women) underwent elective maxillofacial operations during the years 1990-95. Study design and Methods: The patients were randomly assigned to three groups: In group 1, 30 patients preoperatively underwent autologous blood predonation with intravenous injection of erythropoietin 600 IU/kg after each blood predonation and autologous blood transfusion intraoperatively; in group 2, 28 patients underwent the same procedure without erythropoietin and in group 3, 20 patients underwent homologous transfusion serving as control group. All patients received ferrous sulphate daily by mouth, preoperatively until one week postoperatively. Results: Group 1 patients showed higher levels of haematocrit, haemoglobin and red blood cell count pre- and postoperatively than the group 2 patients. It was also shown that the use of rHuEPO contributed to an improvement of the blood parameters of the patients in the group 1 compared with those of the patients in groups 2 and 3. Copyright 2001 European Association for Cranio-Maxillofacial Surgery.

Debate: transfusing to normal haemoglobin levels will not improve outcome

Recent evidence suggests that critically ill patients are able to tolerate lower levels of haemoglobin than was previously believed. It is our goal to show that transfusing to a level of 100 g/l does not improve mortality and other clinically important outcomes in a critical care setting. Although many questions remain, many laboratory and clinical studies, including a recent randomized controlled trial (RCT), have established that transfusing to normal haemoglobin concentrations does not improve organ failure and mortality in the critically ill patient. In addition, a restrictive transfusion strategy will reduce exposure to allogeneic transfusions, result in more efficient use of red blood cells (RBCs), save blood overall, and decrease health care costs.

The efficacy of autologous blood transfusion in bilateral total knee arthroplasty

A controlled, randomised, prospective study was undertaken to assess the efficacy of the use of a blood re-infusion device in the reduction of allogenic blood requirements of patients undergoing bilateral simultaneous total knee replacements. Thirty-three consecutive patients were randomised to receive allogenic blood only, or a combination of collected and re-infused blood. An average of 1000 ml of drainage blood was salvaged in the study group, resulting in a significant reduction in allogenic blood requirements from 6.3 to 3.8 units in total (P value=0.002). No patients suffered transfusion reactions. We conclude that autologous re-infusion is a safe and effective method of reducing allogenic blood requirements, and as a result, reducing the risks of transmission of infection, and the rate of post-operative infection.

Cost-effectiveness of epoetin and autologous blood donationin reducing allogeneic blood transfusions incoronary artery bypass graft surgery

BACKGROUND

Coronary artery bypass graft (CABG) surgery accounts for a substantial portion of all allogeneic units of blood transfused. Drugs and autologous blood donation (ABD) are alternative or adjunctive methods for reducing complications and costs induced by allogeneic blood transfusions. Recombinant human erythropoietin (epoetin) has the potential to decrease perioperative need for allogeneic blood during CABG, but its high cost calls for a careful economic evaluation before it can be recommended for widespread use.

STUDY DESIGN AND METHODS

A decision tree was used to compare a hypothetical strategy of no epoetin with one in which epoetin was utilized to control blood transfusion needs in CABG; each strategy was tested with and without ABD. The impact of these strategies on both the quality-adjusted life years (QALYs) and costs ($US) was calculated.

RESULTS

Using epoetin alone and with ABD, respectively, avoided the transfusion of 0.61 and 1.35 units of allogeneic blood per patient and saved 0.000086 and 0.000146 QALYs per patient. This made cost-effectiveness (CE) higher than $7 million and $5 million for each QALY saved, respectively. ABD alone cost more than $1 million per QALY saved. If the risk of bacterial infections following allogeneic transfusions was included in the model, epoetin alone cost $6288 per QALY saved, while ABD, both alone and with epoetin, saved money.

CONCLUSION

On the basis of the existing evidence, neither of the blood-saving strategies modeled was a cost-effective means of avoiding the deleterious health effects of perioperative blood transfusions in CABG. However, if allogeneic blood-related infections were to be considered, both ABD and epoetin would be acceptable interventions.

Evaluation of a rapid immunochromatographic test for detection of antibodies to human immunodeficiency virus

A new immunochromatographic rapid test, Determine HIV-1/2, for the detection of antibodies to human immunodeficiency virus type 1 (HIV-1) and HIV-2 in human whole blood, serum, and plasma was evaluated. Determine HIV-1/2 is a sandwich immunoassay and uses a nitrocellulose strip with a capture site for the patient's results and a procedural control site to confirm the validity of the assay. The results can be read visually, and a positive result is indicated by the formation of a red line within 15 min after sample application. The test showed 100% sensitivity for HIV-1 with 102 whole-blood, 152 serum, and 144 plasma samples obtained from Ramathibodi Hospital, Bangkok, Thailand. The sensitivity of the test for HIV-2 was 100% with 100 serum or plasma samples obtained from Ivory Coast. The sensitivity of the test with 4 anti-HIV-1 seroconversion panels from Boston Biomedica Inc. was equivalent to or better than those of another agglutination assay with serum or plasma and the enzyme immunoassay licensed by the U.S. Food and Drug Administration. The specificity was 100% with 367 sets of whole-blood, serum, and plasma samples from Ramathibodi Hospital. This method had an analytical sensitivity for the detection of HIV-1 equivalent to or better than that of another agglutination assay with serum or plasma. This test had an analytical sensitivity for the detection of HIV-1 better than that of another immunochromatographic test with whole blood. This evaluation demonstrated the excellent performance of this immunochromatographic test with EDTA-anticoagulated whole-blood, serum, and plasma samples. We conclude that this test is suitable for use in emerging countries and is an excellent alternative to HIV antibody testing at remote sites, as well as in traditional laboratories.

Gains in life expectancy from medical interventions--standardizing data on outcomes

BACKGROUND

The gain in life expectancy is an important measure of the effectiveness of medical interventions, but its interpretation requires that it be placed in context. The interpretation of gains in life expectancy is particularly problematic for preventive interventions, for which the gains are often just weeks or even days when averaged across the entire target population.

METHODS

We tabulated the gains in life expectancy from a variety of medical interventions as reported in 83 published sources and categorized them according to target population and disease. We considered prevention in populations at average risk for particular diseases, prevention in populations at elevated risk, and treatments in populations with established disease.

RESULTS

The gains in life expectancy from preventive interventions in populations at average risk ranged from less than one month to slightly more than one year per person receiving the intervention, but the gains were as high as five years or more if the prevention was targeted at persons at especially high risk. The gains in life expectancy from treatments of established disease ranged from several months (for coronary thrombolysis and revascularization to treat heart disease) to as long as nine years (for chemotherapy to treat advanced testicular cancer).

CONCLUSIONS

A gain in life expectancy from a medical intervention can be categorized as large or small by comparing it with gains from other interventions aimed at the same target population. A gain in life expectancy of a month from a preventive intervention targeted at populations at average risk and a gain of a year from a preventive intervention targeted at populations at elevated risk can both be considered large. The framework we developed for standardizing gains in life expectancy can be used in the interpretation of data on the outcomes of interventions.

Safety and Cost Effectiveness of a 10 × 109/L Trigger for Prophylactic Platelet Transfusions Compared With the Traditional 20 × 109/L Trigger: A Prospective Comparative Trial in 105 Patients With Acute Myeloid Leukemia

In 105 consecutive patients with de novo acute myeloid leukemia (French-American-British M3 excluded), we compared prospectively the risk of bleeding complications, the number of platelet and red blood cell transfusions administered, and the costs of transfusions using two different prophylactic platelet transfusion protocols. Two hundred sixteen cycles of induction or consolidation chemotherapy and 3,843 days of thrombocytopenia less than 25 × 109/L were evaluated. At the start of the study, each of the 17 participating centers decided whether they would use a 10 × 109/L prophylactic platelet transfusion trigger (group A/8 centers) or a 20 × 109/L trigger (group B/9 centers). Bleeding complications (World Health Organization grade 2-4) during treatment cycles were comparable in the two groups: 20 of 110 (18%) in group A and 18 of 106 (17%) in group B (P = .8). Serious bleeding events (grade 3-4) were generally not related to the patient's platelet count but were the consequence of local lesions and plasma coagulation factor deficiencies due to sepsis. Eighty-six percent of the serious bleeding episodes occurred during induction chemotherapy. No patient died of a bleeding complication. There were no significant differences in the number of red blood cell transfusions administered between the two groups, but there were significant differences in the number of platelet transfusions administered per treatment cycle: pooled random donor platelet concentrates averaged 15.4 versus 25.4 (P < .01) and apheresis platelets averaged 3.0 versus 4.8 (P < .05) for group A versus group B, respectively. This resulted in the cost of platelet therapy being one third lower in group A compared with group B without any associated increase in bleeding risk.

Safety and Cost Effectiveness of a 10 × 109/L Trigger for Prophylactic Platelet Transfusions Compared With the Traditional 20 × 109/L Trigger: A Prospective Comparative Trial in 105 Patients With Acute Myeloid Leukemia

In 105 consecutive patients with de novo acute myeloid leukemia (French-American-British M3 excluded), we compared prospectively the risk of bleeding complications, the number of platelet and red blood cell transfusions administered, and the costs of transfusions using two different prophylactic platelet transfusion protocols. Two hundred sixteen cycles of induction or consolidation chemotherapy and 3,843 days of thrombocytopenia less than 25 × 109/L were evaluated. At the start of the study, each of the 17 participating centers decided whether they would use a 10 × 109/L prophylactic platelet transfusion trigger (group A/8 centers) or a 20 × 109/L trigger (group B/9 centers). Bleeding complications (World Health Organization grade 2-4) during treatment cycles were comparable in the two groups: 20 of 110 (18%) in group A and 18 of 106 (17%) in group B (P = .8). Serious bleeding events (grade 3-4) were generally not related to the patient's platelet count but were the consequence of local lesions and plasma coagulation factor deficiencies due to sepsis. Eighty-six percent of the serious bleeding episodes occurred during induction chemotherapy. No patient died of a bleeding complication. There were no significant differences in the number of red blood cell transfusions administered between the two groups, but there were significant differences in the number of platelet transfusions administered per treatment cycle: pooled random donor platelet concentrates averaged 15.4 versus 25.4 (P < .01) and apheresis platelets averaged 3.0 versus 4.8 (P < .05) for group A versus group B, respectively. This resulted in the cost of platelet therapy being one third lower in group A compared with group B without any associated increase in bleeding risk.

Shed mediastinal blood transfusion after cardiac operations: a cost-effectiveness analysis

BACKGROUND

Cardiac surgical patients consume a significant fraction of the annual volume of allogeneic blood transfused. Scavenged autologous blood may serve as a cost-effective means of conserving donated blood and avoiding transfusion-related complications.

METHODS

This study examines 834 patients after cardiac operations at the University of Alabama Hospital. Data were collected on patients receiving unwashed, filtered, autologous transfusions from shed mediastinal drainage and those receiving allogeneic transfusions. The data were incorporated into clinical decision models; confidence intervals for parameters were estimated by bootstrapping sample statistics. Costs were estimated for transfusing both allogeneic and autologous blood.

RESULTS

The study found a 54% reduction in transfusion risk or a mean reduction of 1.41 allogeneic units per case (95% confidence interval, 1.04 to 1.79 units). The process saved between $49 and $62 per case.

CONCLUSIONS

The use of autologous blood has the potential to significantly reduce the costs and risks associated with transfusing allogeneic blood after cardiac operations.

Hemodilution with other blood reinfusion techniques in total hip arthroplasty

Acute normovolemic hemodilution has been reported to result in blood savings varying from 18% to 90%. Very few of these are randomized prospective studies. This study attempts to determine the blood transfusion savings if acute normovolemic hemodilution is used in combination with autologous predonated blood and cell saver. Thirty-three patients undergoing total hip arthroplasty were assigned randomly to one of two groups (control, n = 16; hemodilution, n = 17). Patients in both groups entered an autologous predonation program if cleared medically and were placed on Cell Saver intraoperatively and in the postanesthesia care unit. In addition, the hemodilution group underwent acute normovolemic hemodilution preoperatively. Only 41% of the patients in the hemodilution group required any autologous blood transfusion as compared with 75% of the control group. In addition, the hemodilution group required a mean lower quantity of autologous blood transfusion (41% of the estimated blood loss) as compared with the control group (71%). The net anesthesia time increased by an average of 11.4 minutes in the hemodilution group. Acute normovolemic hemodilution is a safe procedure even in an older patient population. Hemodilution resulted in fewer patients needing autologous predonated blood transfusions. The major benefit of hemodilution was seen when predonation was not possible.

Preoperative autologous blood donation and plateletpheresis in patients undergoing elective cardiac operations--factors that influence the need for homologous blood transfusion

An increased awareness of the adverse effects of homologous blood transfusion prompted us to initiate a blood conservation program consisting of preoperative autologous blood donation and platelet-rich plasma-pheresis. We studied 120 patients who underwent elective cardiac surgery at Aomori General Hospital between January 1991 and September 1994. If their hemoglobin values exceeded 12 g/ml, 400 g of whole blood was drawn 3 times before the operation. Platelet-poor plasma was collected 10 days before the operation and platelet-rich plasma was collected the day before the operation. However, despite participation in this program, 42 of 120 patients (35%) required homologous blood transfusion perioperatively. Factors that influenced the need for homologous blood transfusion were identified retrospectively, with the following found to be significant by univariate analysis: operative procedures performed, cardiopulmonary bypass time, and the amount of autologous blood and autologous plasma donated. Although the effectiveness of our blood conservation procedure remains to be verified, it reduced the need for the transfusion of homologous blood. Thus, additional units of autologous blood are required to obviate the need for homologous transfusion in patients undergoing long cardiopulmonary bypass procedures.

Cost comparison of recombinant human erythropoietin and blood transfusion in cancer chemotherapy-induced anemia

OBJECTIVE

To compare the cost of recombinant human erythropoietin (rHuEPO) with that of blood transfusion in the treatment of chemotherapy-induced anemia from a healthcare system perspective.

DESIGN

A decision analytic model. Baseline estimates were obtained from a review of clinical trials data and economic evaluation studies.

SUBJECTS

Secondary data analyses of patients with advanced malignancies, excluding hematologic malignancies and metastasized solid tumors.

INTERVENTIONS

Patients received either leukocyte-depleted packed red blood cells (PRBCs) or rHuEPO 150 units/kg s.c. three times per week for 6 months (24 wk). After 6 weeks, if rHuEPO recipients did not display a response, they received rHuEPO 300 units/kg s.c. three times weekly for the duration of therapy. If rHuEPO recipients still exhibited no response, they were given blood transfusions.

MEASUREMENTS AND MAIN RESULTS

For a treatment period of 24 weeks, approximately 64% of rHuEPO recipients responded at an average expected cost of $12971 per patient. One hundred percent of transfusion recipients responded at a cost of $481; this resulted in a cost savings of $8490. Variation of response rates for rHuEPO or PRBCs did not appreciably lower costs. Lower rHuEPO dosages and higher numbers of transfused units of PRBCs yielded approximately equivalent costs; however, these strategies may not be clinically prudent.

CONCLUSIONS

From a healthcare system cost and outcome perspective, blood transfusion is the preferred strategy for chemotherapy-induced anemia. However, rHuEPO may be considered an effective blood-sparing alternative for patients with non-stem cell disorders. Future cost-effectiveness analyses are needed to assess more completely both the clinical and quality-of-life benefits rHuEPO may contribute to individual patients' lives and to society overall.

Blood loss during radical retropubic prostatectomy: is preoperative autologous blood donation indicated?

PURPOSE

We assessed the requirement for transfusion of allogeneic blood in a contemporary series of patients who did not deposit autologous blood before radical retropubic prostatectomy.

MATERIALS AND METHODS

After a policy was adopted in which preoperative autologous blood was not donated, 124 consecutive patients underwent radical retropubic prostatectomy. Type and screen for allogeneic blood were routinely available but neither hemodilation nor a cell saver was used.

RESULTS

Mean intraoperative blood loss was 579 cc and mean postoperative serum hematocrit was 33%. Only 3 patients (2.4%) required blood products due to intraoperative blood loss (2) and postoperative bleeding from a duodenal ulcer (1).

CONCLUSIONS

Transfusion of blood products was required in a small percentage of our patients even without autologous blood donation. Therefore, the overall cost of care is decreased but, more importantly, the potential risks associated with autologous or allogeneic blood transfusion are eliminated.

Estimated risk of transmission of the human immunodeficiency virus by screened blood in the United States

BACKGROUND

In the United States, transmission of the human immunodeficiency virus (HIV) by blood transfusion occurs almost exclusively when a recently infected blood donor is infectious but before antibodies to HIV become detectable (during the "window period"). We estimated the risk of HIV transmission caused by transfusion on the basis of the window period associated with the use of current, sensitive enzyme immunosorbent assays and recent data on HIV incidence among blood donors.

METHODS

We analyzed demographic and laboratory data on more than 4.1 million blood donations obtained in 1992 and 1993 in 19 regions served by the American National Red Cross, as well as the results of HIV-antibody tests of 4.9 million donations obtained in an additional 23 regions.

RESULTS

We estimated that, in the 19 study regions, 1 donation in every 360,000 (95 percent confidence interval, 210,000 to 1,140,000) was made during the window period. In addition, it is estimated that 1 in 2,600,000 donations was HIV-seropositive but was not identified as such because of an error in the laboratory. We estimated that 15 to 42 percent of window-period donations were discarded because they were seropositive on laboratory tests other than the HIV-antibody test. When these results were extrapolated to include the additional 23 Red Cross service regions, there was a risk of one case of HIV transmission for every 450,000 to 660,000 donations of screened blood. If the Red Cross centers are assumed to be representative of all U.S. blood centers, among the 12 million donations collected nationally each year an estimated 18 to 27 infectious donations are available for transfusion.

CONCLUSIONS

The estimated risk of transmitting HIV by the transfusion of screened blood is very small and nearly half that estimated previously, primarily because the sensitivity of enzyme immunosorbent assays has been improved.

A model for predicting transfusion requirements in head and neck surgery

INTRODUCTION

Although allogeneic blood transfusions have allowed surgeons increased latitude in resecting advanced cancers, they can cause significant morbidity or even death in rare instances. Potential side effects may include transmission of infection and immunosuppression leading to an increased risk of cancer recurrence. Because patients have become more reluctant to receive transfusions, they frequently request preoperative autologous blood donation (PABD). In practice, however, only 50% or less of the donated blood is ultimately transfused while the remainder is discarded.

PURPOSE

The purpose of this study was to develop a transfusion prediction and risk assessment (TPRA) model for predicting the need for perioperative blood transfusions in patients undergoing major head and neck oncologic surgical procedures. By knowing the probability for blood transfusion, the physician and patient can make an educated decision regarding the need for PABD.

PATIENTS AND METHODS

Over a 4-year period, 436 patients underwent major head and neck surgical procedures for neoplasms of the upper aerodigestive tract, the thyroid gland, and the salivary glands. Data obtained prospectively on each patient included age and gender, the TNM stage, primary disease site, type of prior treatment, estimated intraoperative blood loss, duration of surgery, transfusion requirements, preoperative and postoperative hemoglobin and hematocrit levels, type of procedure and method of reconstruction. These variables were examined singly and in combination both for descriptive purposes and to evaluate their interrelationships. In order to develop the TPRA model, only the 12 variables available prior to the surgical procedure were examined. Variables associated with transfusion need were evaluated further in a multivariate analysis. The logistic regression model allowed a linear expression of patient characteristics to be related to a function of the probability of transfusion need. Analyses of association between categorical variables and transfusion status were based on chi-squared, Fisher's Exact, and Mann-Whitney U tests.

RESULTS

Overall, 51 (11.7%) patients required blood transfusions. The median number of units transfused was 2.0 (range, 1 to 13 U). Univariate analysis demonstrated a higher probability for blood replacement in patients with oropharyngeal or hypopharyngeal primary tumor sites, a preoperative hemoglobin level below normal, prior chemotherapy, composite resection, flap reconstruction, between 50 and 59 years of age, and T3 or T4 tumor stage. Logistic regression analysis demonstrated that the need for flap reconstruction, a preoperative hemoglobin below the normal level, and T3 or T4 primary stage were the three factors most significantly associated with the need for transfusion (P < .03). Based on eight combinations of these three variables, transfusion risk predictions were obtained. The TPRA model predicted that patients with a normal hemoglobin level who did not require flap reconstruction and did not have either a T3 or T4 primary stage tumor had the lowest probability (.02) for requiring blood transfusion. Patients at highest risk (.65) were those with less than a normal hemoglobin level, who required flap reconstruction, and had T3 or T4 primary tumor stage. Based on the TPRA model, an algorithm was developed which could serve as a guideline for preoperative transfusion planning.

CONCLUSION

By using the TPRA model to change guidelines for preoperative transfusion planning, costs can theoretically be reduced by 50% without significantly increasing the risk of exposing patients to allogeneic blood transfusion. If the TPRA model proves accurate in a follow-up study to test its validity, it may have clinical utility for aiding the surgeon in more cost-effective transfusion planning.

The cost effectiveness of preoperative autologous blood donations

BACKGROUND

Since the recognition that human immunodeficiency virus is transmissible by blood transfusion there has been increasing public and professional support for autologous blood donations before elective surgery. Autologous blood donation is, however, a more expensive process than the donation of allogeneic blood by community volunteers. Furthermore, there have been recent improvements in the safety of the volunteer blood supply.

METHODS

We used a decision-analysis model to assess the cost effectiveness of donating autologous blood for four surgical procedures. Cost data were collected from the observation of transfusion practice at the University of California, Los Angeles, in 1992. Estimates of the risks of transfusion-associated diseases and the costs of treating them came from the medical literature. Cost effectiveness was expressed in dollars per quality-adjusted year of life saved. We performed sensitivity analyses of the variables in our model and examined the effect of strategies suggested to reduce costs.

RESULTS

Substituting autologous for allogeneic blood resulted in little expected health benefit (0.0002 to 0.00044 quality-adjusted year of life saved) at considerable additional cost ($68 to $4,783 per unit of blood). The additional cost of autologous blood was primarily a function of the discarding of units that were donated but not transfused and of a more labor-intensive donation process. The cost-effectiveness ratios ranged from $235,000 to over $23 million per quality-adjusted year of life saved.

CONCLUSIONS

Given the improved safety of allogeneic transfusions today, the increased protection afforded by donating autologous blood is limited and may not justify the increased cost.

Impact of autologous blood predonation on a comprehensive blood conservation program

Preoperative autologous donation has been shown to be a highly effective measure in reducing homologous blood use in cardiac operations. The aim of our study was to verify the effectiveness of this procedure and to see whether it is compatible with a comprehensive blood conservation program. Three hundred forty-eight patients (group 1) donated an average of 657 +/- 199 mL of blood before open heart operation, whereas 344 patients (group 2) without autologous predonation were used as a control. The two groups were compared with regard to homologous blood use and the possibility of applying other blood conservation measures. Homologous transfusion rate in group 1 was 12.6%, whereas in group 2 it was 46% (p < 0.001). Patients with three units of predonated autologous blood had a transfusion rate of 0.8% (p < 0.001 compared with group 2). In group 1, acute normovolemic hemodilution was accomplished in a lower number of patients and with a lower average withdrawal (338 +/- 102 versus 403 +/- 145 mL; p < 0.001). Other blood conservation measures such as the return of mediastinal drainage and use of residual blood of extracorporeal circulation were applied with similar results in both groups. In our experience, preoperative autologous donation was compatible with the application of other blood conservation measures, but acute normovolemic hemodilution was achieved in a lower number of patients. Preoperative autologous donation proved to be a highly effective method for reducing banked blood use and therefore homologous blood exposure during and after cardiac operations.

The clinician's approach to the management of risk

Although risk has always been accepted as an integral part of any medical or surgical therapy, it is only in recent years that quantitation of this risk in transfusion medicine is being assessed in a detailed and practical manner. Balancing of the risk/benefit equation in relation to blood component therapy has only become a day-to-day issue in clinical medicine since the recognition that HIV could be transmitted by blood transfusion. Blood transfusion has never been as safe a procedure as most patients and clinicians have thought, with numerous potential complications and new ones being recognized. As medical teaching in blood component therapy has not had a high profile in most undergraduate and postgraduate medical curricula, there has been an inappropriately low level of awareness for the indications for the risks and benefits of blood component therapy. Since the appearance of transfusion-transmitted HIV, clinicians and patients alike have rapidly become aware of the potential risks associated with transfusion medicine. This paper addresses the issues of how the clinician can minimize the risks of blood component therapy and to effectively present the risks and benefits to clinical users and potential recipients of blood component therapy. Paradoxically, in developed countries, transfusion therapy is probably safer than it has ever been in the past, but the perception of the community is the opposite. Why is this so?, and what can be done to improve that patient's perception and associated fear? The ultimate answer rests with improving assessment of risks versus benefits, effective education and communication with the patient (and relatives) in order to achieve meaningful informed consent.

Transfusion and surgery

In this survey of transfusion in surgery, we have attempted to provide the surgeon with an understanding of the problems associated with homologous transfusion and a practical knowledge of treatment strategies and alternatives designed to reduce homologous blood exposure. Such a review cannot be encyclopedic. Our hope is that it will serve the reader as a stimulus to examine his or her transfusion practices and as a guide for future self-learning.

Blood transfusion related HBV and HIV infection in a patient with SLE

We described the course of a young man with SLE who developed hepatitis B virus and human immunodeficiency virus infections through contaminated blood transfusion. He presented with severe SLE, improved on treatment and then developed hepatic failure which responded to conservative treatment. He now has AIDS and the SLE and HBV infection are quiescent.

Is a hemoglobin of 10 g/dL required for surgery?

The "10/30" (hemoglobin/hematocrit) rule has long been recognized and accepted in the medical community as the threshold for transfusion in the perioperative setting. However, an increasing number of publications suggest there is no absolute threshold for transfusion, and that this decision should be based on an assessment of the overall clinical picture presented by the patient. This article reviews the risks associated with blood transfusions, and the data in humans and animals that describe the benefits of transfusion. Recommendations on the trigger for red cell transfusion are provided.