Evaluation of oxygen availability with oxygen status algorithm in patients undergoing open heart surgery treated with epoetin beta

Effects of preoperative intravenous erythropoietin plus iron on outcome in anemic patients after cardiac valve replacement

Preoperative anemia is a risk factor for postoperative morbidity and in-hospital mortality in cardiac surgery. However, it is not known whether treatment of anemia before cardiac surgery by administering recombinant human erythropoietin (rhEPO) plus iron improves postoperative outcomes and decreases red blood cell transfusions in these patients. In 1998 a collection of consecutive data for patients who underwent valve replacement was initiated and the inclusion criterion was anemia. Treatment with rhEPO was given at a dose of 500 IU/kg/day every week for 4 weeks and the fifth dose 48 hours before valve replacement. During each rhEPO session, patients received intravenous iron sucrose supplementation. The intervention cohort (2006 to 2011) included 75 patients and the observation cohort was composed of 59 patients who did not receive any treatment (1998 to 2005). Multivariable logistic regression analysis showed that administration of combined therapy was independently associated with decreased postoperative morbidity (odds ratio [OR] 0.13, 95% confidence interval [CI] 0.03 to 0.59 p = 0.008) and in-hospital mortality (OR 0.16, 95% CI 0.28 to 0.95 p = 0.04) after adjusting for logistic European System for Cardiac Operative Risk Evaluation score, type of intervention, time of cardiopulmonary bypass, and year of surgery. Individually, this treatment also decreased postoperative renal failure (OR 0.23, 95% CI 0.06 to 0.88, p = 0.03). Rate of red blood cell transfusion decreased from 93% in the observation cohort to 67% in the intervention cohort as did days of hospitalization (median, 15 days, 10 to 27, versus 10 days, 8 to 14, respectively, p = 0.01 for all comparisons). In conclusion, administration of intravenous rhEPO plus iron in anemic patients before valve replacement improves postoperative survival, decreases blood transfusions, and shortens hospitalization.

Does the Use of Erythropoietin Reduce the Risk of Exposure to Allogeneic Blood Transfusion in Cardiac Surgery? A Systematic Review and Meta-Analysis

BACKGROUND

The use of blood conservation techniques is important in cardiac surgery as postoperative bleeding is common and allogeneic blood transfusion carries the risk of transfusion reactions and infection transmission. Erythropoietin with and without preoperative autologous blood donation is one of the modalities to avoid allogeneic blood transfusion. The objective of this review was to assess the effectiveness of erythropoietin in reducing the risk of exposure to allogeneic blood transfusion during or after cardiac surgery.

METHODS

A meta-analysis of 11 identified randomized controlled trials, reporting comparisons between erythropoietin and control, was undertaken. The primary outcome was the number of patients exposed to allogeneic blood transfusion during or after cardiac surgery.

RESULTS

Eleven studies, involving 708 patients, met the inclusion criteria for this review. In total, 471 patients were given erythropoietin, and 237 patients formed the control group. The administration of erythropoietin with and without preoperative autologous blood transfusion prior to cardiac surgery is associated with a significant risk reduction: RR = 0.28 (95% CI 0.18-0.44, P < 0.001) and RR = 0.53 (95% CI 0.32-0.88, P < 0.01), respectively.

CONCLUSION

The administration of erythropoietin before cardiac surgery is associated with a significant reduction in the risk of exposure to allogeneic blood transfusion. Further studies are warranted to define the patients' subgroups that may benefit the most from EPO administration.

Autologous blood transfusion in elective cardiac valve operations

BACKGROUND AND AIM OF STUDY

The aim of this study was to detect any outcome differences between patients who donated autologous blood versus nondonors undergoing nonemergent cardiac valve surgery. Of further interest was whether autologous donors required less allogeneic blood products overall than patients who did not donate.

METHODS

We conducted a nested case-control study in which data were collected prospectively on 225 variables. Cases underwent nonemergent, cardiac valve surgery and donated autologous blood products (n = 40). Controls also had nonemergent, cardiac valve surgery but did not donate autologous blood products (n = 120). Cases were matched to controls 1:3 on age (+/-3 years), gender, and New York Heart Association Functional Classification. We controlled for 12 potential confounding variables and examined 17 outcomes of interest. To generate the unadjusted risks of each outcome, chi-square and t-tests were performed comparing cases and controls to each outcome of interest. Then logistic regression analysis investigated the adjusted risk between cases and controls and for the outcomes of interest, each controlling for the potential confounding variables.

RESULTS

There were no significant differences between the cases and controls for 11 of the 12 possible confounding variables. Controls had significantly more chronic obstructive pulmonary disorder. There were no significant differences between cases and controls for 13 of the 17 outcomes of interest. Autologous blood donors received more total packed red blood cells (PRBCs) (p = 0.0373) and more total fresh frozen plasma than controls (p = 0.0002). Fewer autologous blood donors required allogeneic packed red blood cell transfusion (p = 0.0134), and the total length of stay was shorter for autologous donors (p = 0.0782).

CONCLUSION

Four of the 17 outcomes of interest were different for patients who donated autologous blood versus those who did not. Our experience demonstrated that elective cardiac valve surgery can safely reduce (by 18.3%) the need for allogeneic PRBCs by utilizing preoperative autologous blood donation.

The effect of correction of mild anemia in severe, resistant congestive heart failure using subcutaneous erythropoietin and intravenous iron: a randomized controlled study

OBJECTIVES

This is a randomized controlled study of anemic patients with severe congestive heart failure (CHF) to assess the effect of correction of the anemia on cardiac and renal function and hospitalization.

BACKGROUND

Although mild anemia occurs frequently in patients with CHF, there is very little information about the effect of correcting it with erythropoietin (EPO) and intravenous iron.

METHODS

Thirty-two patients with moderate to severe CHF (New York Heart Association [NYHA] class III to IV) who had a left ventricular ejection fraction (LVEF) of < or =40% despite maximally tolerated doses of CHF medications and whose hemoglobin (Hb) levels were persistently between 10.0 and 11.5 g% were randomized into two groups. Group A (16 patients) received subcutaneous EPO and IV iron to increase the level of Hb to at least 12.5 g%. In Group B (16 patients) the anemia was not treated. The doses of all the CHF medications were maintained at the maximally tolerated levels except for oral and intravenous (IV) furosemide, whose doses were increased or decreased according to the clinical need.

RESULTS

Over a mean of 8.2+/-2.6 months, four patients in Group B and none in Group A died of CHF-related illnesses. The mean NYHA class improved by 42.1% in A and worsened by 11.4% in B. The LVEF increased by 5.5% in A and decreased by 5.4% in B. The serum creatinine did not change in A and increased by 28.6% in B. The need for oral and IV furosemide decreased by 51.3% and 91.3% respectively in A and increased by 28.5% and 28.0% respectively in B. The number of days spent in hospital compared with the same period of time before entering the study decreased by 79.0% in A and increased by 57.6% in B.

CONCLUSIONS

When anemia in CHF is treated with EPO and IV iron, a marked improvement in cardiac and patient function is seen, associated with less hospitalization and renal impairment and less need for diuretics.

The pathological consequences of anaemia

Many patients with chronic diseases such as chronic renal failure, chronic inflammatory bowel disease and rheumatoid arthritis are anaemic. Recently congestive heart failure (CHF) has also been found to be associated with anaemia. In all these diseases this anaemia or chronic disease is at least partially due to excessive production of cytokines and leukotrines that interfere both with the effect of erythropoietin (EPO) at the bone marrow and the release of stored iron in the reticuloendothelial system. Treating this anaemia with subcutaneous EPO and IV iron improves the weakness, fatigue, cachexia, nutritional state, mood, cognitive function and quality of life. In the case of CHF it also improves cardiac function and patient functional class, prevents deterioration of renal function and markedly reduces hospitalization. Very few agents in medicine improve so many aspects of the patient so well and so quickly. Unfortunately (for the suffering patient) this anaemia is often ignored and goes untreated.

Efficacy of recombinant human erythropoietin in the critically ill patient: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

To determine whether the administration of recombinant human erythropoietin (rHuEPO) to critically ill patients in the intensive care unit (ICU) would reduce the number of red blood cell (RBC) transfusions required.

DESIGN

A prospective, randomized, double-blind, placebo-controlled, multicenter trial.

SETTING

ICUs at three academic tertiary care medical centers.

PATIENTS

A total of 160 patients who were admitted to the ICU and met the eligibility criteria were enrolled in the study (80 into the rHuEPO group; 80 into the placebo group).

INTERVENTIONS

Patients were randomized to receive either rHuEPO or placebo. The study drug (300 units/kg of rHuEPO or placebo) was administered by subcutaneous injection beginning ICU day 3 and continuing daily for a total of 5 days (until ICU day 7). The subsequent dosing schedule was every other day to achieve a hematocrit (Hct) concentration of >38%. The study drug was given for a minimum of 2 wks or until ICU discharge (for subjects with ICU lengths of stay >2 wks) up to a total of 6 wks (42 days) postrandomization.

MEASUREMENTS AND MAIN RESULTS

The cumulative number of units of RBCs transfused was significantly less in the rHuEPO group than in the placebo group (p<.002, Kolmogorov-Smirnov test). The rHuEPO group was transfused with a total of 166 units of RBCs vs. 305 units of RBCs transfused in the placebo group. The final Hct concentration of the rHuEPO patients was significantly greater than the final Hct concentration of placebo patients (35.1+/-5.6 vs. 31.6+/-4.1; p<.01, respectively). A total of 45% of patients in the rHuEPO group received a blood transfusion between days 8 and 42 or died before study day 42 compared with 55% of patients in the placebo group (relative risk, 0.8; 95% confidence interval, 0.6, 1.1). There were no significant differences between the two groups either in mortality or in the frequency of adverse events.

CONCLUSIONS

The administration of rHuEPO to critically ill patients is effective in raising their Hct concentrations and in reducing the total number of units of RBCs they require.

Erythropoietin therapy in the perioperative setting

Recombinant human erythropoietin has been approved for use in patients undergoing autologous donation in Japan, Europe, and Canada since 1993, 1994, and 1996, respectively, and for perisurgical adjuvant therapy without autologous donation in Canada and the United States since 1996. Early clinical trials of erythropoietin therapy in the setting of autologous donation have provided important information regarding clinical safety, erythropoietin dose, and erythropoietic response. Later trials of perisurgical erythropoietin therapy without autologous donation provided data on efficacy (reduced allogeneic blood exposure) that led to approval of erythropoietin in patients undergoing surgery. However, the erythropoietin doses (300 U/kg subcutaneous x14 days) used in these trials, and their subsequent inclusion in labeling for the use of this product, are costly and tedious to administer. A recent study reported that a weekly regimen of erythropoietin (600 U/kg) for 4 weeks is less costly but just as effective at reducing allogeneic blood exposure in elective orthopaedic surgery. The most cost effective regimen that has been shown to minimize allogeneic exposure is preoperative erythropoietin therapy (600 U/kg subcutaneous weekly x2 and 300 U/kg subcutaneous on day of surgery) coupled with acute normovolemic hemodilution in patients undergoing radical retropubic prostatectomy. A similar regimen of erythropoietin therapy in patients undergoing coronary artery bypass grafting (2500 U/kg subcutaneous in divided doses for 2 weeks preoperatively) coupled with hemodilution also was effective. Low dose erythropoietin therapy coupled with acute normovolemic hemodilution ultimately may be shown to be cost equivalent to the predonation of three autologous blood units before elective surgery.

Anemia in the patient undergoing surgery and the transfusion decision. A review

The heightened awareness of the problems of transfusion reactions, disease transmission, and potential immunosuppression has led surgeons to reevaluate their reasons for transfusion. Current practice policies recommend that elective transfusion of allogeneic blood be avoided whenever possible in patients having surgery. If patients are to have appropriate transfusion, the basic pathophysiology and clinical response of the patient to anemia must be understood. This article reviews the physiologic response to anemia in the patient having surgery and explores the components of the decision to use transfusion.

The estimation of efficacy of oral iron supplementation during treatment with epoetin beta (recombinant human erythropoietin) in patients undergoing cardiac surgery

We estimated the efficacy of oral iron therapy during treatment with rhEPO in patients undergoing cardiac surgery who were contraindicated for autologous blood donation. Seventy-six patients were enrolled in this double-blind, placebo-controlled trial and assigned to the 2 treatment groups (5x500 U/kg body weight rhEPO or placebo intravenously over 14 d before surgery). During the treatment period all patients received 300 mg Fe2+ (iron glycine sulfate) orally per day. rhEPO therapy produced significant increases in hemoglobin concentration (Hb), reticulocyte count, hematocrit (Hct) and the hypochromic red blood cells (HRBC), and a decrease in transferrin saturation (41%) compared to the placebo group before surgery. However, the preoperative increase in HRBC was independent of the baseline ferritin and even correlated positively with the preoperative increase in Hct (r=0.47, p<0.01). In rhEPO patients there were inverse correlations between baseline serum iron and the preoperative increases in Hb (r=-0.39, p<0.05), Hct (r=-0.50, p<0.01) and HRBC (r=-0.53, p<0.001). With this treatment regimen the HRBC appear to reflect the degree of erythropoietic stimulation rather than functional iron deficiency. The preoperative increases in reticulocytes, HRBC and Hb/Hct in patients with ferritin <100 mg/l or transferrin saturation <16% showed no significant difference compared to their complementary groups. The preoperative decrease in storage iron and the inverse correlation between the baseline ferritin and the preoperative change in ferritin (r=-0.94, p<0.0001) in the rhEPO group indicate that the iron requirement for hemoglobin synthesis is probably covered by the breakdown of stored iron and an increase in the rate of absorption of orally administered Fe2+. Intravenous rhEPO treatment with 5x500 U/kg body weight in combination with 300 mg oral Fe2+/d given over 14 d before surgery is a suitable regimen to increase Hb by about 1.61 g/dl and Hct by 0.06.