Response of erythropoiesis and iron metabolism to recombinant human erythropoietin in intensive care unit patients

Use of EPO in Critically Ill Patients With Acute Renal Failure Requiring Renal Replacement Therapy

BACKGROUND

Recombinant human erythropoietin (EPO) is used widely to treat anemia in patients with chronic kidney disease, but the benefits of EPO use in patients with acute renal failure (ARF) are unclear. In vitro and animal studies suggest that EPO may promote renal recovery and decrease mortality in ARF.

METHODS

We conducted a retrospective cohort study at a tertiary-care center to evaluate the use of EPO in 187 critically ill patients with ARF requiring renal replacement therapy.

RESULTS

Compared with patients not administered EPO (n = 116), patients administered EPO (n = 71) were significantly more likely to have baseline chronic kidney disease, have undergone vascular surgery, and have received intermittent hemodialysis, rather than continuous renal replacement therapy. In a propensity-adjusted analysis that controlled for differences between the 2 cohorts and baseline hemoglobin level, EPO use did not decrease the transfusion of packed red blood cells. Renal recovery was not more common in patients administered EPO: the odds ratio for renal recovery in the propensity-adjusted analysis was 0.63 (95% confidence interval, 0.30 to 1.3) with EPO use. In-hospital survival was more common in the EPO-treated group, but this potential benefit was not significant in propensity-adjusted analyses.

CONCLUSION

Although EPO use was not associated with a decrease in transfusion requirements or with renal recovery in our retrospective study, 37% of critically ill patients with ARF were treated with EPO at varying doses. A randomized controlled trial is needed to evaluate the potential benefits of EPO use in patients with ARF.

Impact of anemia on outcome in critically ill patients with severe acute renal failure

OBJECTIVE

To evaluate the prognostic value of hemoglobin levels in critically ill patients with acute renal failure (ARF) requiring dialysis.

DESIGN AND SETTING

A prospective observational cohort study in two adult medical ICUs.

PATIENTS

206 consecutive patients with ARF who required dialysis. Overall 28-day mortality was 48%.

MEASUREMENTS AND RESULTS

At ICU admission mean hemoglobin level was 9.1+/-2.1 g/dl. By ROC curve analysis the threshold value of hemoglobin with the highest sensibility/specificity was 9 g/dl. At baseline 63% of patients had anemia, defined as initial hemoglobin below 9 g/dl. Kaplan-Meier analysis showed that these patients had lower survival rate than those with hemoglobin above 9 g/dl. By multivariable analysis three factors were independently associated with 28-day death: hemoglobin lower than 9 g/dl (adjusted odds ratio 2.4, 95% CI 1.1-5.2), age, and SOFA score. Based on age and SOFA a matched cohort analysis of 67 pairs of ARF patients with or without anemia found similar results regarding the negative impact of anemia on outcome. Finally, a multivariable logistic regression analysis on matched cohort identified hemoglobin level below 9 g/dl (adjusted odds ratio 1.32, 95%CI 1.15-1.46), continuous renal replacement therapy, and vasoactive therapy as independent predictors of 28-day death.

CONCLUSIONS

These results suggest that initial hemoglobin level could be helpful in identifying patients with ARF requiring dialysis at high risk of death.

Blood conservation in the critically ill patient

This review focuses on transfusion practice in the critically ill.

Recombinant human erythropoietin therapy in critically ill patients: a dose-response study [ISRCTN48523317]

Introduction

The aim of this study was to assess the efficacy of two dosing schedules of recombinant human erythropoietin (rHuEPO) in increasing haematocrit (Hct) and haemoglobin (Hb) and reducing exposure to allogeneic red blood cell (RBC) transfusion in critically ill patients.

Method

This was a prospective, randomized, multicentre trial. A total of 13 intensive care units participated, and a total of 148 patients who met eligibility criteria were enrolled. Patients were randomly assigned to receive intravenous iron saccharate alone (control group), intravenous iron saccharate and subcutaneous rHuEPO 40,000 units once per week (group A), or intravenous iron saccharate and subcutaneous rHuEPO 40,000 units three times per week (group B). rHuEPO was given for a minimum of 2 weeks or until discharge from the intensive care unit or death. The maximum duration of therapy was 3 weeks.

Results

The cumulative number of RBC units transfused, the average numbers of RBC units transfused per patient and per transfused patient, the average volume of RBCs transfused per day, and the percentage of transfused patients were significantly higher in the control group than in groups A and B. No significant difference was observed between group A and B. The mean increases in Hct and Hb from baseline to final measurement were significantly greater in group B than in the control group. The mean increase in Hct was significantly greater in group B than in group A. The mean increase in Hct in group A was significantly greater than that in control individuals, whereas the mean increase in Hb did not differ significantly between the control group and group A.

Conclusion

Administration of rHuEPO to critically ill patients significantly reduced the need for RBC transfusion. The magnitude of the reduction did not differ between the two dosing schedules, although there was a dose response for Hct and Hb to rHuEPO in these patients.

Perioperative stimulation of erythropoiesis with intravenous iron and erythropoietin reduces transfusion requirements in patients with hip fracture. A prospective observational study

BACKGROUND AND OBJECTIVES

Patients undergoing surgery for hip fracture (HF) often receive perioperative allogeneic blood transfusions (ABT) to avoid anaemia. However, concerns about the adverse effects of ABT have prompted the review of transfusion practice and the search for a safer treatment of perioperative anaemia.

MATERIALS AND METHODS

We prospectively investigated the effect of a blood-saving protocol of perioperative iron sucrose (3 x 200 mg/48 h, intravenously) plus erythropoietin (1 x 40,000 IU, subcutaneously) if admission haemoglobin level < 130 g/l, on transfusion requirements and postoperative morbid-mortality in patients with HF (group 2; n= 83). A parallel series of 41 HF patients admitted to another surgical unit within the same hospital served as the control group (group 1). Perioperative blood samples were taken for haematimetric, iron metabolism and inflammatory parameter determination.

RESULTS

This blood-saving protocol reduced the number of transfused patients (P < 0.001), the number of transfused units (P < 0.0001), increased the reticulocyte count and improved iron metabolism. In addition, the blood-saving protocol also reduced the rate of postoperative infections (P = 0.016), but not the 30-day mortality rate or the mean length of hospital stay.

CONCLUSIONS

The blood-saving protocol implemented seems to reduce ABT requirements in patients with HF, and is associated with a lower postoperative morbidity. The possible mechanisms involved in these effects are discussed.

Cost-effectiveness of recombinant human erythropoietin for reducing red blood cells transfusions in critically ill patients

OBJECTIVE

To examine the cost-effectiveness of using recombinant human erythropoietin (rHuEPO) to reduce red blood cells (RBC) transfusions in intensive care unit (ICU) patients.

METHODS

Decision analysis examining costs and effectiveness of using rHuEPO versus not using rHuEPO in a simulated adult medical/surgical/trauma (mixed) ICU. Two independent cost-effectiveness models were created based on the results of two multicenter studies that investigated the use of rHuEPO. Base case assumptions and estimates of effectiveness were obtained from these two studies. Mean cumulative doses of rHuEPO were 190,900 units and 102,400 units for studies 1 and 2, respectively. The models accounted for the deferral rate for allogeneic RBC transfusions, rHuEPO efficacy (the reduction in allogeneic RBC use), and adverse effects of rHuEPO and allogeneic RBC transfusions. Model estimates were obtained from published sources. Costs were expressed in 2002 US dollar (dollars) and effectiveness was measured using discounted quality-adjusted life-years (QALYs). A 3% discount rate was used. Probabilistic sensitivity analysis was conducted using second-order Monte Carlo simulation.

RESULTS

Incremental costs of using rHuEPO to reduce RBC transfusions amounted to 1918 dollars and 1439 dollars; incremental effectiveness values were 0.0563 QALYs and 0.0305 QALYs; and the cost-effectiveness ratios were 34,088 dollars and 47,149 dollars per QALY for studies 1 and 2, respectively. The model was most sensitive to the attributable risk of nosocomial bacterial infections per RBC unit. rHuEPO was cost-effective in 52.0% of the Monte Carlo simulations for a willingness to pay of 50,000 dollars/QALY.

CONCLUSION

rHuEPO appears to be cost-effective for reducing RBC transfusions in heterogeneous ICU populations, assuming RBC transfusions increase the risk of nosocomial bacterial infections.

Anemia, allogenic blood transfusion, and immunomodulation in the critically ill

Anemia and allogenic RBC transfusions are exceedingly common among critically ill patients. Multiple pathologic mechanisms contribute to the genesis of anemia in these patients. Emerging risks associated with allogenic RBC transfusions including the transmission of newer infectious agents and immune modulation predisposing the patient to infections requires reevaluation of current transfusion strategies. Recent data have suggested that a restrictive transfusion practice is associated with reduced morbidity and mortality during critical illness, with the possible exception of acute coronary syndromes. In this article, we review the immune-modulatory role of allogenic RBC transfusions in critically ill patients.

Anemia in critically ill patients

Anemia is common in acute critically ill patients. Although blood loss, either by trauma, surgery, phlebotomies or gastrointestinal bleeding, may play a role, the anemia in these patients bears many similarities to the anemia characteristic of chronic disease. Serum iron is low with a high concentration of ferritin and low-to-normal transferrin and serum transferrin receptor levels. Several mechanisms may be involved, with inflammation playing a crucial role. Although the exact nature of the inflammatory response and the role of various cytokines need further elucidation, it is known that inflammation blunts the responsiveness of the hormone erythropoietin and induces functional iron deficiency. Iron is trapped in cells of the mononuclear phagocytic system and its release is temporarily blocked. The bone marrow is still capable of incorporating iron and of responding to treatment with recombinant human erythropoietin (rh-EPO). The duration of the anemia is related to the persistence of the inflammation. Although the effects of anemia on morbidity and mortality in the critically ill are poorly defined, a restrictive transfusion policy, in which hemoglobin concentration is maintained between 7.0 and 9.0 g/dl, proves to be at least as effective as, if not superior to, a more liberal regimen. In individual situations, such as in cardiovascular and cancer patients, higher thresholds may be appropriate. The administration of rh-EPO is an alternative to reduce the need for red blood cell transfusions and to avoid transfusion-related complications. Although its efficacy has been shown, questions regarding cost-benefit, dose regimen and clinical outcomes need to be answered before its large-scale use can be recommended.

[Erythropoietin treatment in critically ill children]

OBJECTIVE

To analyze whether erythropoietin treatment increases hemoglobin and decreases transfusion requirements in critically ill children.

PATIENTS AND METHODS

We performed an observational, prospective study of 23 critically ill children aged between 1 month and 6 years. Recombinant human eritropoietin (rHuEPO) was administered at a dosage of 150-750 U/kg/week over 3 days. Hemogram, reticulocyte, iron metabolism, serum ferritin and transferrin were measured before treatment started and weekly thereafter.

RESULTS

After erythropoietin treatment, hematocrit, hemoglobin and red blood cells progressively increased, with a maximal response in the sixth week. At the end of treatment, hemoglobin increased 1.68 g/dl, hematocrit by 5 % and erythrocytes 600,000/ml/mm3. Transfusion requirements decreased from 59 transfusions at baseline to 12 in the first week of treatment and none from the sixth week. No treatment-related adverse effects were observed.

CONCLUSION

Erythropoietin can be an effective treatment for anemia in some critically ill children, decreasing the number of transfusions and increasing hemoglobin.

Relationship of baseline glucose homeostasis to hyperglycemia during medical critical illness

STUDY OBJECTIVE

To elucidate the relationship of baseline glucose control and acute stimuli with hyperglycemia during medical critical illness.

DESIGN

Prospective cohort study.

SETTING

Medical ICU (MICU) of a university affiliated hospital.

PATIENTS

Convenience sample of 100 medical patients meeting criteria for severity of illness and anticipated length of stay and not admitted to the hospital for diabetic ketoacidosis or a hyperglycemic hyperosmolar state.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patients were categorized as having normal, abnormal, or unevaluable baseline glucose control based on history and glycosylated hemoglobin (HbA1c). Data collection included blood glucose measurements within 120 h of MICU admission, and dosing of norepinephrine, corticosteroids, propofol, and carbohydrates. Average blood glucose and times over glycemic thresholds were calculated using linear interpolation. Hyperglycemia (glucose > 110 mg/dL) was pervasive in all groups. Among the 51 patients with normal baseline glucose control, HbA1c was correlated with hyperglycemic time (p < 0.01, R(2) = 0.15). Multiple regression found HbA1c, age, corticosteroid dose, and carbohydrate administration independently associated with hyperglycemic time (p < 0.05 for each, total R(2) = 0.49) in these patients, while body mass index, APACHE (acute physiology and chronic health evaluation) II, norepinephrine dose, propofol dose, gender, and sepsis were not associated with time > 110 mg/dL. Among normal subjects, HbA1c was independently predictive of peak and average glucose, and the fraction of time glucose was > 150 mg/dL and > 200 mg/dL (p < 0.05 for each). Patients with abnormal baseline glucose control had significantly more hyperglycemia than patients with normal baseline control.

CONCLUSIONS

Even in patients without evidence of abnormal glucose homeostasis at baseline, hyperglycemia is common during critical illness. Time exposure to hyperglycemia is correlated with acute stressors and baseline glucose regulation, as characterized by HbA1c. Patients with low HbA1c levels are less disposed to hyperglycemia during severe illness than patients with higher, but still normal, HbA1c.

Use of blood products in sepsis: An evidence-based review

OBJECTIVE

In 2003, critical care and infectious disease experts representing 11 international organizations developed management guidelines for the use of blood products in sepsis that would be of practical use for the bedside clinician, under the auspices of the Surviving Sepsis Campaign, an international effort to increase awareness and to improve outcome in severe sepsis.

DESIGN

The process included a modified Delphi method, a consensus conference, several subsequent smaller meetings of subgroups and key individuals, teleconferences, and electronic-based discussion among subgroups and among the entire committee.

METHODS

The modified Delphi methodology used for grading recommendations built on a 2001 publication sponsored by the International Sepsis Forum. We undertook a systematic review of the literature graded along five levels to create recommendation grades from A to E, with A being the highest grade. Pediatric considerations to contrast adult and pediatric management are in the article by Parker et al. on p. S591.

CONCLUSION

In the absence of extenuating circumstances and following resolution of tissue hypoperfusion, red blood cell transfusion should be targeted to maintain hemoglobin at 7.0 g/dL or greater. Erythropoietin is not recommended as a specific treatment for sepsis-associated anemia. Fresh-frozen plasma should be given for documented deficiency of coagulation factors and in the presence of active bleeding or before surgical or invasive procedures. Antithrombin administration is not recommended. Specific platelet transfusion thresholds are based on the presence or absence of bleeding, significant risk for bleeding, plans for surgery or invasive procedures, and platelet count </=5,000/mm.

Patients with pertrochanteric hip fracture may benefit from preoperative intravenous iron therapy: a pilot study

BACKGROUND

Patients undergoing pertrochanteric hip fracture (PHF) repair surgery often receive perioperative allogeneic blood transfusions (ABTs) to avoid the deleterious effects of anemia. Nevertheless, concerns about adverse effects of ABTs have prompted the review of transfusion practice and the search for a safer treatment of perioperative anemia.

MATERIAL AND METHODS

The effect of preoperative 200 to 300 mg of intravenous (IV; Group 2; n = 55) iron sucrose administration on transfusion requirements and postoperative morbidity-mortality in patients with PHF has been prospectively investigated. A previous series of 102 PHF patients served as the control group (Group 1). All patients were older than 65 years and were operated on at the third day after admission to the hospital, by the same medical team and with the same implant.

RESULTS

Iron sucrose was well tolerated and reduced the transfusion rate in patients with admission hemoglobin levels of greater than 120 g per L (p < 0.05) who also received fewer units of red blood cells (p < 0.05). In addition, iron sucrose reduced postoperative infection rate (p < 0.05), but not 30-day mortality rate or mean length of hospital stay.

CONCLUSION

The administration of IV iron sucrose seems to reduce ABT requirements in patients with PHF and is associated to lower postoperative morbidity. The possible mechanisms involved in these effects are discussed.

Erythropoietin for Prevention and Treatment of Anemia in the Intensive Care Unit

Objective:

To evaluate and summarize the data on erythropoietin (EPO) use to prevent anemia in intensive care unit (ICU) patients.

Data Sources:

A literature search was performed using MEDLINE (1966–December 2003) using the key words erythropoietin, intensive care unit, anemia, and critically ill.

Data Synthesis:

Attempts to decrease the complications associated with anemia in ICU patients have recently focused on EPO use. Two comprehensive studies found that EPO significantly reduced the cumulative number of blood transfusions as compared to that of placebo. The assessing outcomes found no difference between the groups with respect to mortality rates, ventilation days, or length of stay.

Conclusions:

Available trials demonstrate reduced blood transfusions in ICU patients when EPO is administered. However, this result has not carried over as a defined clinical benefit. EPO use should be reserved for patients with longer hospital stays who are at risk for frequent blood transfusions as a comprehensive blood conservation strategy in the ICU.

Indications et limites de l'utilisation d'érythropoïétine recombinée en réanimation

OBJECTIVE

To analyze the data from the literature on erythropoietin and the future indications of recombinant human erythropoietin in intensive care unit (ICU) patients.

DATA SOURCE

References were obtained from computerized bibliographic research (Pubmed) from 1986 to 2003, except for some physiologic data.

DATA SELECTION

Original articles, reviews, and letters to editor in French and English were selected and analyzed.

DATA SYNTHESIS

An anemia is often observed in patients hospitalized in ICU. This anemia may be due to many reasons. The management of anemia consists on the treatment of the underlying disease associated with the transfusion of red blood cells. Recent studies provided evidence of an association between transfusions and mortality in ICU patients. The anemia of ICU patients is compared to the anemia of chronic diseases, which is characterized by a blunted erythropoietin. A treatment with rHuEPO may be a future therapeutic of the anemia in such patients. A multicentric study shows the efficacy of recombinant erythropoietin therapy on a decrease in the use of red blood cell, and another clinical trial highlights a decrease of the proportion of ICU patients receiving red blood cell. Recombinant erythropoietin could be an alternative to transfusion in certain conditions and certain ICU patients. Further studies are needed to determine the consequences on mortality rate and to clarify the place of this therapy in ICU patients.

Science review: recombinant human erythropoietin in critical illness: a role beyond anemia?

Erythropoiesis usually fails during severe illness because of a blunting of the kidney-erythropoietin (EPO)-bone marrow axis. In this setting, clinical studies have shown that recombinant human erythropoietin (rhEPO), administered in pharmacological amounts, significantly reduces the need for blood transfusions. In addition to the kidney, however, EPO is also produced locally by other tissues in a paracrine-autocrine manner. Here, similar to its role in the bone marrow, EPO rescues cells from apoptosis. Additionally, EPO reduces inflammatory responses, restores vascular autoregulation, and promotes healing. The results of many studies (including a phase II clinical trial in ischemic stroke) demonstrate that rhEPO protects the brain, spinal cord, retina, heart, and kidney from ischemic and other types of injury. Although rhEPO is efficacious in the treatment of EPO-deficient anemia during illness, inadequate effort has been devoted to determining whether direct tissue protection might also result from its administration. Here, we speculate on the potential utility of EPO as a protective cytokine in the context of acute critical illness and suggest key parameters required for a proof-of-concept clinical study.

Anemia and blood transfusion in the critically ill patient: role of erythropoietin

Critically ill patients receive an extraordinarily large number of blood transfusions. Between 40% and 50% of all patients admitted to intensive care units receive at least 1 red blood cell (RBC) unit during their stay, and the average is close to 5 RBC units. RBC transfusion is not risk free. There is little evidence that 'routine' transfusion of stored allogeneic RBCs is beneficial to critically ill patients. The efficacy of perioperative recombinant human erythropoietin (rHuEPO) has been demonstrated in a variety of elective surgical settings. Similarly, in critically ill patients with multiple organ failure, rHuEPO therapy will also stimulate erythropoiesis. In a randomized, placebo-controlled trial, therapy with rHuEPO resulted in a significant reduction in RBC transfusions. Despite receiving fewer RBC transfusions, patients in the rHuEPO group had a significantly greater increase in hematocrit. Strategies to increase the production of RBCs are complementary to other approaches to reduce blood loss in the intensive care unit, and they decrease the transfusion threshold in the management of all critically ill patients.

Pathophysiology of intensive care unit-acquired anemia

The formation of red blood cells (RBCs) in the bone marrow is regulated by erythropoietin in response to a cascade of events. Anemia in the intensive care unit can be caused by a host of factors. Patients in the intensive care unit may have decreased RBC production and a blunted response to erythropoietin. Administration of recombinant human erythropoietin may stimulate erythropoiesis, increase hematocrit levels and hemoglobin concentration, and reduce the need for RBC transfusions.

Iron supplementation in the intensive care unit: when, how much, and by what route?

Derangements of iron metabolism may be present in critically ill patients who develop anemia during a stay in the intensive care unit. Iron supplementation may be appropriate, especially if an underlying nutritional disorder is present. It may be even more critical to replace iron when erythropoietin therapy is used because of the consumption of iron stores that occurs during heme synthesis. Iron therapy is not without risks, and controversy persists regarding the potential for iron overload and infections. Clinical trials that define the optimal dose, route, and timing of iron administration in critically ill patients are lacking. However, studies of iron supplementation in chronic kidney disease, pregnancy, and anemia of prematurity may provide some guidance about approaches to treatment. Clinical evidence and limitations that can assist clinicians in managing iron therapy in the intensive care unit are presented.

Role of iron in anaemic critically ill patients: it's time to investigate!

Anaemia is a common problem in critically ill patients admitted to intensive care units. Many factors can be involved in its development, including rapid alterations of iron metabolism. Maintenance of iron homeostasis is a prerequisite for many essential biological processes and a central element for the development of erythroid precursors and mature red blood cells. With the inflammatory process, iron distribution is disturbed, with decreased serum iron levels and increased iron stores. Little information is available on the precise role of alterations of iron metabolism in the development of iron anaemia in critically ill patients.

Use of exogenous erythropoietin in critically ill patients

OBJECTIVE

Review the literature regarding the use of recombinant human erythropoietin (rHuEPO) to prevent red blood cell (RBC) transfusion in critically ill patients.

DATA SOURCES

A computerized search of MEDLINE and EMBASE from 1966 through June 2003 was conducted using the terms erythropoietin, anemia, hemoglobin, critical care, intensive care, surgery, trauma, burn, and transfusion. References of selected articles were reviewed. A manual search of critical care, surgery, trauma, burn, hematology, and pharmacy journals was conducted to identify relevant abstracts.

RESULTS

Six randomized studies have evaluated exogenous administration of erythropoietin to prevent RBC transfusions in critically ill patients. Studies vary with respect to rHuEPO dosage regimens, dose of concurrently administered iron, patient characteristics, and transfusion thresholds. Administration of rHuEPO rapidly produces erythropoiesis to reduce the need for RBC transfusions. The largest study conducted to date used weekly rHuEPO administration and found a modest decrease in transfusion requirements although the time to first transfusion was delayed. Reduced intensive care unit (ICU) length of stay (LOS) was shown in only one study of surgical/trauma patients. Reduced LOS after ICU discharge was found in another study of severely ill patients (APACHE II score >22). Other clinical outcomes were not altered by rHuEPO use. No adverse events were associated with rHuEPO use although studies were not designed to evaluate safety.

CONCLUSIONS

rHuEPO reduces the need for transfusions. A cost-effectiveness analysis of rHuEPO for this indication is needed. Defining an optimal dosage regimen, identifying patients most likely to respond to rHuEPO, and determining risk factors for ICU associated anaemia would provide information for appropriate rHuEPO utilization.

Is there a place for epoetin alfa in managing anemia during critical illness?

BACKGROUND

Anemia is a common problem in critically ill patients. As a result, blood transfusions are often used in the intensive care unit (ICU) setting. However, mounting evidence shows that blood transfusions may contribute to negative outcomes, such as transfusion-related infections, organ dysfunction, and immunosuppression. Supplementation with epoetin alfa is currently used in some medical centers to manage anemia in critically ill patients.

OBJECTIVE

This review discusses the risks with blood transfusions and the clinical evidence supporting the use of epoetin alfa in managing edema during critical illness.

METHODS

A search was conducted in MEDLINE and Current Contents (1966-2003) using the terms epoetin alfa, recombinant human erythropoietin, and anemia. Articles addressing anemia and the use of epoetin alfa in critically ill patients were selected and assessed. From this selection, the cited references addressing the etiology of anemia in the ICU and the risks associated with blood transfusions were manually extracted and reviewed.

RESULTS

Several reports have shown that critically ill patients display evidence of anemia due to a blunted erythropoietin response. One large, randomized, placebo-controlled study assessed the effect of SC epoetin alfa on blood transfusions in the ICU. In this study, 40, 000 IU administered weekly for up to 4 weeks resulted in an overall transfusion reduction (9.9% absolute risk reduction; P<0.001 ). Other, smaller studies using different dosing regimens in critically ill patients have also demonstrated that epoetin alfa can decrease the need for transfusion.

CONCLUSION

The use of epoetin alfa in critically ill patients can decrease the number of blood transfusions required during hospitalization, and potentially result in transfusion avoidance. Because of the scarce amount of evidence and the diversity of dosing regimens used used, no strict recommendations can be drawn from this review.

Bench-to-bedside review: iron metabolism in critically ill patients

Critically ill patients frequently develop anemia due to several factors. Iron-withholding mechanisms caused by inflammation contribute to this anemia. The iron metabolism imbalances described or reported in all intensive care studies are similar to the values observed in anemia of inflammation. The administration of iron could be useful in the optimization of recombinant human erythropoietin activity, but this could be at the expense of bacterial proliferation. Since there is a lack of evidence to support either oral or intravenous iron administration in intensive care patients, further studies are necessary to determine the efficacy and safety of iron supplementation in conjunction with recombinant human erythropoietin in critically ill patients. We review the mechanisms leading to iron sequestration in the presence of inflammation. The present article also reviews the literature describing the iron status in critically ill patients and explores the role of iron supplementation in this setting.

Anemia in the critically ill

The anemia of critical illness is a distinct clinical entity with characteristics similar to that of chronic disease anemia. Several solutions to the processes of anemia, such as blunted erythropoietin production and erythropoietin response and abnormalities in iron metabolism have been developed. The transfusion of RBCs provides immediate correction of low hemoglobin levels, which may be of value in patients with life-threatening anemia. Avoidance of RBC and blood component transfusion, however, is becoming increasingly important as data of adverse clinical outcomes in critically ill patients become clearer. Although the optimal hemoglobin in critically ill patients is not determined, this organ system has a generous reserve. Short-term compensated anemia is tolerated well, while exogenous erythropoietin allows patients to achieve higher hemoglobin concentrations without exposure to transfused blood/blood components. A recent randomized trial enrolled over 1300 critically ill patients to receive either 40,000 units of exogenous erythropoietin or placebo. These authors found that patients randomized to erythropoietin received significantly less allogeneic RBC transfusions and had significantly greater increases in hemoglobin. Although no differences were found between groups in gross clinical outcomes (ie, death, renal failure, myocardial infarction), this study did not have the power to identify small differences in outcomes. This and other studies of exogenous erythropoietin therapy in critically ill patients clearly demonstrate that the bone marrow in many of these patients will respond to the administration of erythropoietin despite their illness, suggesting a blunted production of erythropoietin rather than a blunted response to erythropoietin. Exogenous erythropoietin therefore represents a therapeutic option for treating anemia in critical illness. Acute events in medicine and surgery often lead to many patients becoming anemic. Solutions to this process of anemia should be focused on preventing such events. Anemia after surgery represents an area for prevention. Blood conservation strategies can be performed with adequate results. Monk et al randomized 79 patients undergoing radical prostatectomy to preoperative autologous donation (PAD), preoperative exogenous erythropoietin therapy plus ANH immediately following induction of general anesthesia, and ANH alone. This study concluded that all three techniques resulted in similar hemostasis outcomes (eg, bleeding and transfusion rates), but ANH alone was the least expensive, and ANH plus exogenous erythropoietin and ANH alone resulted in a higher ICU hematocrit compared with PAD. Regardless of these prophylactic strategies, patients still become anemic after surgery or during critical illness. This acute event anemia usually is treated with RBC transfusion; however, autologous blood recovery (cell salvage systems) has been shown to be effective in patients with acute bleeding-related anemia, and this may reduce patients' exposure to allogeneic blood in these patients. There are no universally accepted treatment guidelines for managing anemia, and practice differs between clinicians, hospitals, regions, and countries. Transfusion medicine is evolving and incorporating many new pharmacological agents into the armamentarium of anemia and bleeding therapy. Accumulating evidence suggests that anemia in critically ill patients is common and correlated with poor outcomes. The management of anemia can improve outcomes; however, the optimal management of anemia is not performed universally. New approaches, continued research, and an understanding of anemia may result in more consistent and improved outcomes for critically ill patients.

Use of Epoetin Alfa in Critically III Patients

OBJECTIVE

To discuss the controversies regarding the use of epoetin alfa (EPO) for reducing red blood cell (RBC) transfusions in critically ill patients with anemia.

DATA SOURCES

A MEDLINE search (1966–July 2003) was conducted using the search terms anemia; critical illness; erythropoietin; epoetin alfa; and erythropoietin, recombinant. References of selected articles were reviewed for studies that may have been missed by the computerized search.

STUDY SELECTION AND DATA EXTRACTION

Studies pertaining to the use of EPO for anemia of critical illness with an emphasis on data obtained from controlled trials.

DATA SYNTHESIS

Anemia is a common complication in patients admitted to the intensive care unit (ICU). Two prospective, randomized studies have demonstrated decreased transfusion requirements associated with EPO administration in medical/surgical patients who were in the ICU for at least 3 days and had hematocrit concentrations <38%. No differences were found in length of stay or mortality. A multicenter trial found that a restrictive strategy of RBC transfusion (hemoglobin goal 7–9 g/dL) was associated with in-hospital mortality lower than that with a more liberal approach, which calls into question the 38% hematocrit goal in the EPO trials. Furthermore, preliminary results from an economic analysis of EPO use in the ICU setting have demonstrated that EPO is not cost-effective.

CONCLUSIONS

Given the controversies surrounding EPO administration in critically ill patients, institutions are encouraged to develop EPO guidelines to help ensure the most appropriate use of this expensive product. Additional studies regarding patients most likely to benefit from EPO therapy, the most effective dosing regimen, and use of adjunctive therapies are needed.

Managing Anemia in the Critically Ill Patient

Anemia of critical illness is a multifactorial condition caused by phlebotomy, ongoing blood loss, and inadequate production of red blood cells. It occurs early in the course of critical illness. Although red blood cell transfusion is the treatment of choice for immediate management of anemia in the intensive care unit, controversy surrounds the most appropriate hemoglobin concentration or hematocrit "trigger." Therapeutic options, including blood-conservation tools, minimization of phlebotomy, erythropoietic agents, and investigational oxygen-carrying agents, may be alternatives to red blood cell transfusions in critically ill patients with anemia. Patient selection for erythropoietic agents will depend on further work dealing with outcomes and the total cost of care in managing the anemia of critical illness.

The CRIT Study: Anemia and blood transfusion in the critically ill—Current clinical practice in the United States*

OBJECTIVE

To quantify the incidence of anemia and red blood cell (RBC) transfusion practice in critically ill patients and to examine the relationship of anemia and RBC transfusion to clinical outcomes.

DESIGN

Prospective, multiple center, observational cohort study of intensive care unit (ICU) patients in the United States. Enrollment period was from August 2000 to April 2001. Patients were enrolled within 48 hrs of ICU admission. Patient follow-up was for 30 days, hospital discharge, or death, whichever occurred first.

SETTING

A total of 284 ICUs (medical, surgical, or medical-surgical) in 213 hospitals participated in the study.

PATIENTS

A total of 4,892 patients were enrolled in the study.

MEASUREMENTS AND MAIN RESULTS

The mean hemoglobin level at baseline was 11.0 +/- 2.4 g/dL. Hemoglobin level decreased throughout the duration of the study. Overall, 44% of patients received one or more RBC units while in the ICU (mean, 4.6 +/- 4.9 units). The mean pretransfusion hemoglobin was 8.6 +/- 1.7 g/dL. The mean time to first ICU transfusion was 2.3 +/- 3.7 days. More RBC transfusions were given in study week 1; however, in subsequent weeks, subjects received one to two RBC units per week while in the ICU. The number of RBC transfusions a patient received during the study was independently associated with longer ICU and hospital lengths of stay and an increase in mortality. Patients who received transfusions also had more total complications and were more likely to experience a complication. Baseline hemoglobin was related to the number of RBC transfusions, but it was not an independent predictor of length of stay or mortality. However, a nadir hemoglobin level of <9 g/dL was a predictor of increased mortality and length of stay.

CONCLUSIONS

Anemia is common in the critically ill and results in a large number of RBC transfusions. Transfusion practice has changed little during the past decade. The number of RBC units transfused is an independent predictor of worse clinical outcome.

Transfusion practice in the critically ill

BACKGROUND

Anemia in the critically ill patient population is common. This anemia of critical illness is a distinct clinical entity characterized by blunted erythropoietin production and abnormalities in iron metabolism identical to what is commonly referred to as the anemia of chronic disease.

FINDINGS

As a result of this anemia, critically ill patients receive an extraordinarily large number of blood transfusions. Between 40% and 50% of all patients admitted to intensive care units receive at least one red blood cell unit, and the average is close to five red blood cell units during their intensive care unit stay. There is little evidence that "routine" transfusion of stored allogeneic red blood cells is beneficial for critically ill patients. Most critically ill patients can tolerate hemoglobin levels as low as 7 mg/dL, so a more conservative approach to red blood cell transfusion is warranted.

CONCLUSION

Practice strategies should be directed toward a reduction of blood loss (phlebotomy) and a decrease in the transfusion threshold in critically ill patients.

Anaemia and red blood cell transfusion in the critically ill patient

Anaemia is a common finding in critically ill patients. There are often multiple causes. Obvious causes include surgical bleeding and gastrointestinal haemorrhage but many patients have no overt bleeding episodes. Phlebotomy can be a significant source of blood loss. In addition, critically ill patients have impaired erythropoiesis as a consequence of blunted erythropoietin production and direct inhibitory effects of inflammatory cytokines. The ability of a patient to tolerate anaemia depends on their clinical condition and the presence of any significant co-morbidity; maintenance of circulating volume is of paramount importance. There is no universal transfusion trigger. Current guidelines for critically ill and perioperative patients advise that at Hb values <70 g/L red blood cell transfusion is strongly indicated and at Hb values >100 g/L transfusion is unjustified. For patients with Hb values in the range 70 to 100 g/L the transfusion trigger should be based on clinical indicators. Most stable critically ill patients can probably be managed with a Hb concentration between 70 and 90 g/L. Uncertainties exist concerning the most appropriate Hb concentration for patients with significant cardio-respiratory disease.

Red blood cell physiology in critical illness

OBJECTIVE

Reduction in red blood cell mass, as well as structural and functional alterations of erythrocytes, occurs in critical illness. This review discusses these changes in red blood cell physiology, emphasizing the pathogenesis of anemia in intensive care unit patients.

DATA SOURCE

Studies published in biomedical journals.

DATA SYNTHESIS AND CONCLUSION

Anemia in intensive care unit patients resembles the anemia of chronic disease, being characterized by diminished erythropoietin production relative to decreased hematocrit, altered iron metabolism, and impaired proliferation and differentiation of erythroid progenitors in the bone marrow. Inflammatory mediators play a major role in the development of insufficient erythropoiesis and altered iron metabolism. Furthermore, a proinflammatory milieu promotes structural and functional alterations of erythrocytes, impairing their deformability and possibly impairing microvascular perfusion. Collectively, these changes in red blood cell physiology can impair oxygen transport to tissues and, thereby, might contribute to the development of multiple organ failure in critical illness.

Critical issues in nephrology

Renal and electrolyte problems are common in patients in the ICU. Several advances that occurred in the recent past have been incorporated in the diagnosis and management of these disorders and were reviewed in this article. Unfortunately, many important questions remain unanswered, especially in the area of ARF, where new therapies are anxiously awaited to make the transition from bench to bedside. Better studies are sorely needed to define the best approach to dialysis in patients who have ARF.

The use of erythropoietin

EPO is a hematopoietic growth factor produced in the kidney that stimulates erythropoiesis. It effectively treats hypoproliferative anemia associated with CRF, improving quality of life in these patients. Other uses that are poorly characterized in veterinary medicine include treatment of cancer patients on chemotherapy, hematologic disorders, and anemic FeLV-infected cats as well as preoperative conditioning for elective surgeries that may involve significant blood loss. Careful monitoring of therapy is necessary for optimal results. Several complications are associated with rHuEPO therapy. The production of anti-rHuEPO antibodies is the most significant and can be a life-threatening event. Alternatives to human EPO are being sought to provide beneficial effects while avoiding antibody formation.

Recombinant erythropoietin in clinical practice

The introduction of recombinant human erythropoietin (RHuEPO) has revolutionised the treatment of patients with anaemia of chronic renal disease. Clinical studies have demonstrated that RHuEPO is also useful in various non-uraemic conditions including haematological and oncological disorders, prematurity, HIV infection, and perioperative therapies. Besides highlighting both the historical and functional aspects of RHuEPO, this review discusses the applications of RHuEPO in clinical practice and the potential problems of RHuEPO treatment.

The hematologic system as a marker of organ dysfunction in sepsis

Sepsis with acute organ dysfunction (severe sepsis) results from a systemic proinflammatory and procoagulant response to infection. Organ dysfunction in the patient with sepsis is associated with increased mortality. Although most organs have discrete anatomical boundaries and carry out unified functions, the hematologic system is poorly circumscribed and serves several unrelated functions. This review addresses the hematologic changes associated with sepsis and provides a framework for prompt diagnosis and rational drug therapy. Data sources used include published research and review articles in the English language related to hematologic alterations in animal models of sepsis and in critically ill patients. Hematologic changes are present in virtually every patient with severe sepsis. Leukocytosis, anemia, thrombocytopenia, and activation of the coagulation cascade are the most common abnormalities. Despite theoretical advantages of using granulocyte colony-stimulating factor to enhance leukocyte function and/or circulating numbers, large clinical trials with these growth factors are lacking. Recent studies support a reduction in the red blood cell transfusion threshold and the use of erythropoietin treatment to reduce transfusion requirements. Treatment of thrombocytopenia depends on the cause and clinical context but may include platelet transfusions and discontinuation of heparin or other inciting drugs. The use of activated protein C may provide a survival benefit in subsets of patients with severe sepsis. The hematologic system should not be overlooked when assessing a patient with severe sepsis. A thorough clinical evaluation and panel of laboratory tests that relate to this organ system should be as much a part of the work-up as taking the patient's blood pressure, monitoring renal function, or measuring liver enzymes.

Soluble transferrin receptor for the evaluation of erythropoiesis and iron status

Iron transport in the plasma is carried out by transferrin, which donates iron to cells through its interaction with a specific membrane receptor, the transferrin receptor (TfR). A soluble form of the TfR (sTfR) has been identified in animal and human serum. Soluble TfR is a truncated monomer of tissue receptor, lacking its first 100 amino acids, which circulates in the form of a complex of transferrin and its receptor. The erythroblasts rather than reticulocytes are the main source of serum sTfR. Serum sTfR levels average 5.0+/-1.0 mg/l in normal subjects but the various commercial assays give disparate values because of the lack of an international standard. The most important determinant of sTfR levels appears to be marrow erythropoietic activity which can cause variations up to 8 times below and up to 20 times above average normal values. Soluble TfR levels are decreased in situations characterized by diminished erythropoietic activity, and are increased when erythropoiesis is stimulated by hemolysis or ineffective erythropoiesis. Measurements of sTfR are very helpful to investigate the pathophysiology of anemia, quantitatively evaluating the absolute rate of erythropoiesis and the adequacy of marrow proliferative capacity for any given degree of anemia, and to monitor the erythropoietic response to various forms of therapy, in particular allowing to predict response early when changes in hemoglobin are not yet apparent. Iron status also influences sTfR levels, which are considerably elevated in iron deficiency anemia but remain normal in the anemia of inflammation, and thus may be of considerable help in the differential diagnosis of microcytic anemia. This is particularly useful to identify concomitant iron deficiency in a patient with inflammation because ferritin values are then generally normal. Elevated sTfR levels are also the characteristic feature of functional iron deficiency, a situation defined by tissue iron deficiency despite adequate iron stores. The sTfR/ferritin ratio can thus describe iron availability over a wide range of iron stores. With the exception of chronic lymphocytic leukemia (CLL) and high-grade non-Hodgkin's lymphoma and possibly hepatocellular carcinoma, sTfR levels are not increased in patients with malignancies. We conclude that soluble TfR represents a valuable quantitative assay of marrow erythropoietic activity as well as a marker of tissue iron deficiency.

Erythropoietin mimics the acute phase response in critical illness

BACKGROUND

In a prospective observational study, we examined the temporal relationships between serum erythropoietin (EPO) levels, haemoglobin concentration and the inflammatory response in critically ill patients with and without acute renal failure (ARF).

PATIENTS AND METHOD

Twenty-five critically ill patients, from general and cardiac intensive care units (ICUs) in a university hospital, were studied. Eight had ARF and 17 had normal or mildly impaired renal function. The comparator group included 82 nonhospitalized patients with normal renal function and varying haemoglobin concentrations. In the patients, levels of haemoglobin, serum EPO, C-reactive protein, IL-1beta, IL-6, serum iron, ferritin, vitamin B12 and folate were measured, and Coombs test was performed from ICU admission until discharge or death. Concurrent EPO and haemoglobin levels were measured in the comparator group.

RESULTS

EPO levels were initially high in patients with ARF, falling to normal or low levels by day 3. Thereafter, almost all ICU patients demonstrated normal or low EPO levels despite progressive anaemia. IL-6 exhibited a similar initial pattern, but levels remained elevated during the chronic phase of critical illness. IL-1beta was undetectable. Critically ill patients could not be distinguished from nonhospitalized anaemic patients on the basis of EPO levels.

CONCLUSION

EPO levels are markedly elevated in the initial phase of critical illness with ARF. In the chronic phase of critical illness, EPO levels are the same for patients with and those without ARF, and cannot be distinguished from noncritically ill patients with varying haemoglobin concentrations. Exogenous EPO therapy is unlikely to be effective in the first few days of critical illness.

Blood Transfusion Issues in the Critically Ill

Anemia is a common clinical problem seen in the critically ill and results in a large RBC transfusion requirement for these patients. The view that RBC transfusion is risk-free is no longer tenable today. There is the accumulating evidence that allogeneic blood transfusion is immunosuppressive. More reently, attention has focused on the age of RBCs transfused. Transfused RBCs, especially during the time period immeditely following transfusion, are not normal. The duration of RBC storage may be an important determinant of the efficacy of RBCs as oxygen carriers as well as a determinant of transusion related morbidity. Adding to the controversy about risk/benefit ratio for RBC transfusion are recent data showing that an aggressive RBC transfusion strategy may decrease the likelihood of survival in selected subpopulations of critically ill adults. The optimal hematocrit for the ICU patient remains to be determined. It seems clear that hemoglobin levels falling significantly below the “10/30” threshold can be tolerated. However, it is not clear that this is applicable to the critically ill ICU patient population. Therefore, while hemoglobin levels in the 7-10 mg/dL range are well tolerated in the “stable” “nontressed” patient, this range might not be optimal for the critcally ill patient. Conservative transfusion thresholds as well as strategies to minimize loss of blood and increase the producion of RBCs are important in the management of critically ill patients.

Severe anemia after gastrointestinal hemorrhage in a Jehovah's Witness: new treatment strategies

OBJECTIVE

Management of severe anemia in a critically ill Jehovah's Witness is challenging. In the past, conservative therapy was the only option available to the practitioner. Recently, new interventional treatment strategies have become available, including human and bovine hemoglobin substitutes and high-dose recombinant human erythropoietin.

DESIGN

Case report.

SETTING

Intensive care unit in a quaternary care center.

PATIENT

A patient with severe, life-threatening anemia caused by gastrointestinal hemorrhage who refused all blood products on religious grounds.

INTERVENTION

Bovine hemoglobin substitute and high-dose recombinant human erythropoietin.

CASE STUDY

A 50-yr-old Jehovah's Witness presented with massive upper gastrointestinal hemorrhage; initial hemoglobin was 3.5 g/dL. Endoscopy revealed a prepyloric ulcer, and hemorrhage control was achieved by epinephrine injections into the peri-ulcer mucosa. Despite control of hemorrhage, the patient became hemodynamically unstable. A total of 7 units of a bovine hemoglobin-based oxygen carrying compound (HBOC-201) was administered to enhance the patient's oxygen delivery. High-dose recombinant human erythropoietin was administered daily (500 units/kg). Hemoglobin levels were initially maintained and then slowly increased to a maximum of 7.6 g/dL on day 24 of therapy.

CONCLUSION

This case demonstrates that the concurrent administration of hemoglobin-based oxygen carriers and recombinant human erythropoietin in severe, life-threatening anemia (hemoglobin, 3.5 g/dL) was associated with patient survival and a significant increase in hemoglobin to 7.6 g/dL, without the administration of allogeneic blood. Hemoglobin-based oxygen carriers can adequately serve as initial therapy to maintain tissue oxygen delivery while awaiting the maximal effect of recombinant erythropoietin on bone marrow red blood cell production. High-dose recombinant human erythropoietin offers these patients the best chance for normalization of hematocrit and survival in the long term.

Recombinant human erythropoietin use in intensive care

OBJECTIVE

To review the literature concerning the role of recombinant human erythropoietin (rHuEPO) in reducing the need for transfusion in critically ill patients.

DATA SOURCES

Articles were obtained through searches of the MEDLINE database (from 1990 to June 2001) using the key words erythropoietin, epoetin alfa, anemia, reticulocytes, hemoglobin, critical care, intensive care, critical illness, and blood transfusion. Additional references were found in the bibliographies of the articles cited. The Cochrane library was also consulted.

STUDY SELECTION AND DATA EXTRACTION

Controlled, prospective, and randomized studies on the use of rHuEPO in critically ill adults were selected.

DATA SYNTHESIS

Anemia is a common complication in patients requiring intensive care. It is caused, in part, by abnormally low concentrations of endogenous erythropoietin and is mainly seen in patients with sepsis and multiple organ dysfunction syndrome, in whom inflammation mediator concentrations are often elevated. High doses of rHuEPO produce a rapid response in these patients, despite elevated cytokine concentrations. There have been 3 studies on rHuEPO administration in intensive care and 1 trial in acutely burned patients. Only 2 of these studies looked at the impact of rHuEPO administration on the need for transfusion.

CONCLUSIONS

Few randomized, controlled trials explore the role of rHuEPO in critical care. Only 1 was a large, randomized clinical trial, but it presents many limitations. Future outcome and safety studies comparing rHuEPO with placebo must include clinical endpoints such as end-organ morbidity, mortality, transfusion criteria, and pharmacoeconomic analysis. rHuEPO appears to provide an erythropoietic response. Optimal dosage and the real impact of rHuEPO on the need for transfusion in intensive care remain to be determined. Currently, based on the evidence available from the literature, rHuEPO cannot be recommended to reduce the need for red blood cell transfusions in anemic, critically ill patients.

Clinical Benefits of Epoetin Alfa Therapy in Patients with Lung Cancer

A retrospective subset analysis of anemic lung cancer patients who participated in three large, multicenter, community-based studies of 3-times-weekly (TIW) or once-weekly (QW) recombinant human erythropoietin (r-HuEPO, epoetin alfa) as an adjunct to chemotherapy was conducted. Patients were treated with epoetin alfa 150 U/kg in the first TIW study and with 10,000 U subcutaneously in the other study, with doubling of the dose if hemoglobin (Hb) response was inadequate. Patients in the QW study received epoetin alfa 40,000 U subcutaneously, which could be increased to 60,000 U. The maximum treatment duration for all three studies was 16 weeks. A total of 1748 lung cancer patients were evaluable for hematopoietic response; 1298 were evaluable for analyses of energy and 1300 were evaluable for analyses of activity and overall quality of life (QOL), as measured by the linear analogue scale assessment (LASA). Within 2 months of therapy, TIW and QW epoetin alfa therapy resulted in significant increases in Hb levels, decreases in transfusion requirements, and improvements in self-reported LASA scores. Increased Hb levels and reduced transfusion rates were demonstrated in the individual studies and in the analysis of data pooled from all three studies. Improvements in QOL parameters were significantly correlated with increased Hb levels. Epoetin alfa was well tolerated in all studies. The clinical benefits and safety profiles of the TIW and the QW schedules appear to be similar. In addition, the QW schedule provides greater convenience to patients and physicians alike. Given the high incidence of anemia and transfusion utilization in patients presenting with lung cancer, epoetin alfa is an effective strategy for correcting anemia in these patients, thereby improving their energy levels, activity levels, and overall QOL.

Erythropoietin therapy versus red cell transfusion

Erythropoietin therapy was approved for use as a blood conservation intervention beginning in 1989 for patients with medical anemia and in 1997 for surgical patients. The adoption of this strategy has been rapid in some settings (such as renal failure patients), progressive in others ( eg, cancer patients), and slow in others (surgery patients, for instance). At the same time, the risks of blood transfusion have declined substantially whereas the costs of blood transfusion have increased significantly. The evolution of new techniques such as acute normovolemic hemodilution (ANH) and the novel erythropoiesis-stimulating protein (NESP) bring new options to allogeneic blood transfusion. Erythropoietin therapy, with or without autologous blood procurement, is undergoing new scrutiny as an alternative to blood transfusion. This is not only because of traditional concerns regarding blood risks but because of new blood inventory and cost considerations.