Electrostatic field can preserve red blood cells in stored blood preparations

Purpose During the storage of red blood cell concentrates (CRCs), red blood cells are progressively destroyed and free hemoglobin and potassium concentrations increase. In this study, we focused on an electrostatic field that maintains food freshness without freezing, even at less than the freezing point. We hypothesized that the storage of CRCs under an electrostatic field could keep red blood cells in better condition than conventional storage. Methods Each of 15 packs of 2-day-old CRCs, preserved in MAP (mannitol, adenine, glucose, phosphate, and citrate) solution (MAP-CRC) was divided into 4 smaller equal-size packs and stored at 4°C in a newly developed refrigerator that can generate an electrostatic field. Each group was exposed to a 0-, 500-, 1500-, or 3000-volt (V) electric field for 30 days. Concentrations of free hemoglobin, total haptoglobin, sodium (Na), and potassium (K), and the pH, were measured in the supernatant. Results Haptoglobin was not detected. The Na concentration decreased with time but was significantly lower in the 0-V than in the 500-, 1500-, and 3000-V groups. K and free hemoglobin concentrations increased with time, with significantly higher values in the 0-V than in the 500-, 1500-, and 3000-V groups. The pH decreased in the 500-, 1500-, and 3000-V groups, while it did not change in the 0-V group. The pH decrease was smaller in the 500-V than in the 1500- and 3000-V groups. Conclusion Storing MAP-CRC in an electrostatic field of 500 to 3000 V could decrease hemolysis in the preparation. Considering the lower pH decrease, 500 V might be the field of choice.     

Free hemoglobin concentrations in patients receiving massive blood transfusion during emergency surgery for trauma

PURPOSE: To determine free hemoglobin concentration in patients who received massive blood transfusion during emergency surgery for trauma with consideration of the storage of the transfused blood. METHODS: Fifteen patients undergoing emergency surgery for multiple trauma and who received blood transfusion of more than 5000 mL were studied. Transfusion of the stored whole blood in citrate-phosphate glucose solution using a micropore filter was started before surgery. Serum concentrations of hemoglobin (total:THb and free:fHb) and total haptoglobin (THp) were measured until 5,000 mL of blood had been transfused. Serum free haptoglobin (fHp) concentration was calculated. The correlation between the changes in hemoglobin or haptoglobin concentrations and total storage days of the transfused blood was analyzed by a simple regression analysis. RESULTS: Free hemoglobin was detected after 2,000 mL transfusion. The THp and fHp decreased after 1,000 mL transfusion. Total storage time (days) of transfused blood had correlated with the changes of THp (P < 0.0001) and fHp (P = 0.0027) but not with the changes of THb (P = 0.984) and fHb (P = 0.834). CONCLUSION: After blood transfusion during surgery for trauma, serum haptoglobin concentration decreased with transfusion of > or = 1,000 mL of whole blood with mean storage time of 12.2 dy. Free hemoglobin was detected after 2,000 mL transfusion when THp decreased to 1,000 mgxL(-1). Serum haptoglobin concentrations correlated negatively with storage time (days) of transfused blood.     

The effects of massive transfusion and haptoglobin therapy on hemolysis in trauma patients

A retrospective study was conducted on 53 patients who suffered severe trauma to determine the severity of intravascular hemolysis, the variations of renal function after trauma, and the effects of transfusion and haptoglobin therapy on these factors. Serum total haptoglobin, total hemoglobin, and urine free hemoglobin were measured 0, 1, 3, and 5 days after the trauma and renal tubular function was evaluated by the urinaryN-acetyl--d-glucosaminidase (NAG) index. Patients were divided into two groups depending on whether or not haptoglobin was given: group A (n = 34) did not receive haptoglobin, and group B (n = 19) was administered 4,421 ± 245 U haptoglobin based on clinical indications. The total transfusion volumes were 3,477 ±594 ml and 10,146 ± 1,794 ml, in groups A and B, respectively (P < 0.01). In group A, total haptoglobin was remarkably decreased to 69.4 ± 11.6 mg/dl on day 0, but recovered to within the normal range on day 3, while the total hemoglobin was increased and the urine hemoglobin was positive in 61.8% of the patients. In group B, decreases in total haptoglobin and increases in total hemoglobin were more remarkable, and 84.2% had a positive urine hemoglobin. On day 5, groups A and B had NAG indices of 18.8 ± 3.3 and 133.6 ± 33.8 U/L/creatinine respectively (P < 0.01). These findings led us to conclude that trauma caused hemolysis and that the administration of 4,000 U haptoglobin did not improve either the severity of hemolysis or the deteriorated renal tubular function caused by massive transfusion.     

Evaluation of a pediatric blood filter for whole blood transfusions in domestic chickens (Gallus gallus)

Blood filters that prevent clots, microaggregates, and other debris from being passed from the donor blood into the recipient are an essential component of blood transfusions in mammalian species but have not been consistently recommended in avian transfusions. To evaluate the hemolytic effect of an 18-microm filter in chickens, 9 mL of blood was collected from each of 30 chickens (Gallus gallus) into a syringe containing 1 mL of citrate phosphate dextrose adenine (CPDA-1) to obtain a 1:9 dilution of CPDA-1 to blood. One half of each sample was then run through a pediatric blood filter before separating the plasma. The level of hemolysis in both filtered and unfiltered portions was determined by measuring the concentration of free hemoglobin in the plasma. All samples had low hemoglobin concentrations (less than 30 mg/dL) with no significant difference between the unfiltered and filtered portions. Based on these results, an 18-microm blood filter can be used safely for blood transfusions in domestic chickens as it does not cause significant hemolysis.     

Haptoglobin administration for hemolysis with autotransfusion of blood ultrafiltered after cardiopulmonary bypass

Ultrafiltration is well known as a useful method of hemoconcentration of the blood after cardiopulmonary bypass, but free hemoglobin increase is a problem in autotransfusion. The purpose of this study was to investigate the effect of haptoglobin administration for hemolysis with autotransfused blood ultrafiltered after cardiopulmonary bypass. By means of haptoglobin administration, autotransfusion of blood ultrafiltered with Hemocon (CD Medical Inc.) composed cellulose acetate membrane was performed in patients over a long period (max 313 min) of cardiopulmonary bypass, and with high serum free hemoglobin levels (max 128 mg/dl) at the end of the cardiopulmonary bypass. Comparing the prophylactic administration with the therapeutic administration of haptoglobin, both methods effectively prevented the increment of serum free hemoglobin level, but prophylactic administration (priming administration) was safer and more useful considering free hemoglobin level in ultrafiltered blood and changes of serum free haptoglobin, free hemoglobin and creatinine clearance during and after the operation.     

Rapid in-line blood warming using microwave energy: preliminary studies.

The management of massive blood loss resulting from trauma or surgery necessitates rapid transfusion capability. Hypothermia secondary to shock, transfusion, and prolonged surgical procedures significantly increases morbidity and mortality in these patients. Transfusion at high flow rates frequently exceeds the warming capacity of conventional blood-warming devices, whose inherent resistance also limits the maximal flow rates. Microwave ovens are capable of blood warming, but have been associated with unacceptable hemolysis. We have investigated the possibility of using microwave energy to provide rapid in-line blood warming. Fresh blood from 10 human subjects was warmed from an average of 18 degrees C to temperatures ranging from 37 to 39 degrees C at flow rates from 250 to 500 mL/min. Laboratory analysis of free plasma hemoglobin, haptoglobin, hematocrit, hemoglobin, and electrolytes showed no difference between heated and control samples. LDH was elevated in those samples warmed repeatedly, but remained within the normal range. These data indicate the potential for further investigation utilizing properly controlled microwave energy for in-line blood and fluid warming.     

Haptoglobin determination in the serum of patients following intraoperative autotransfusion using the Haemonetics Cell Saver III. Studies on the loading of patients with free hemoglobin in retransfused erythrocyte concentrate

In addition to hemodilution, mechanical intraoperative autotransfusion (IAT) is the most important method of preventing or minimizing the transfusion of homologous blood in operations with major blood loss. Most of the problems associated with IAT could be solved by the use of cell separators, but the separated red blood cells still contain an average of 200 mg/dl free hemoglobin. By the determination of haptoglobin levels before and after IAT, we studied the effects of free hemoglobin on the patient. Seventy-seven patients with hip-joint replacement were studied. In one group, n = 47, both intraoperative blood loss and drainage blood (for 6 h post-operatively) were collected and transfused back to the patient after cell separation with the Haemonetics Cell-Saver III as a red-cell concentrate. A second group, n = 34, received only homologous blood. Serum haptoglobin was determined after anesthesia induction and after the last transfusion on the day of operation. There were no significant differences in preoperative haptoglobin levels between both groups. In the IAT group, haptoglobin was significantly lower then in the control group after transfusion (t-test, P = 0.05). In both groups 14% of the patients' haptoglobin levels were pathologic preoperatively. Post-transfusion 60% of the IAT group showed minimum levels while in another 14% no haptoglobin could be measured. In these 14%, free hemoglobin was circulating in the patients' blood because the transport capacity was exhausted. In the control group only 26.5% of the haptoglobin levels were below normal and in no case was transport capacity exhausted (Table 3). The correlation between volume of retransfused autologous blood and decrease in haptoglobin level was small (r = 0.15). In a few cases with low volumes of retransfused blood the haptoglobin decrease may have been greater, so that free hemoglobin may have been present.     

氨甲环酸对全膝关节置换术围手术期失血量的影响及安全性评估

目的 探讨氨甲环酸对全膝关节置换术围手术期失血量的影响及安全性.方法 2008年5月至2009年2月,选取98例拟行全膝关节置换术的患者.男35例,女63例.病因:骨性关节炎66例,类风湿关节炎32例.病程2～12年,平均5年.随机分为A、B两组,每组49例:A组在松止血带时将氨甲环酸1 g稀释于250ml生理盐水后静脉点滴,3 h后以相同剂量再次给药;B组仅给予等量生理盐水静脉点滴.以术中失血量、术后可见失血量、输血量、输血人数、术后血红蛋白和术后纤维蛋白原、凝血酶原时间等为评价指标,对两组进行比较.观察患者术后是否出现下肢深静脉栓塞的临床症状,并于术后14d进行下肢血管多普勒检查.结果术中失血量两组比较差异无统计学意义(P>0.05),但术后可见失血量、输血量、输血人数A组均明显少于B组(P<0.05).术后血红蛋白值,A组明显大于B组(P<0.05).两组患者术中松止血带和术后3 h纤维蛋白原、凝血酶原时间和活化部分凝血活酶时间的比较差异无统计学意义(P>0.05).术后14d未发现卜肢深静脉血栓形成.结论 在全膝关节置换术中及术后短期使用氨甲环酸能明显降低患者失血量及输血量,并且不增加静脉血栓形成的风险.     

Rapid In-line Blood Warming Using Microwave Energy: Preliminary Studies

The management of massive blood loss resulting from trauma or surgery necessitates rapid transfusion capability. Hypothermia secondary to shock, transfusion, and prolonged surgical procedures significantly increases morbidity and mortality in these patients. Transfusion at high flow rates frequently exceeds the warming capacity of conventional blood-warming devices, whose inherent resistance also limits the maximal flow rates. Microwave ovens are capable of blood warming, but have been associated with unacceptable hemolysis. We have investigated the possibility of using microwave energy to provide rapid in-line blood warming. Fresh blood from 10 human subjects was warmed from an average of 18 °C to temperatures ranging from 37 to 39 °C at flow rates from 250 to 500 mL/min. Laboratory analysis of free plasma hemoglobin, haptoglobin, hematocrit, hemoglobin, and electrolytes showed no difference between heated and control samples. LDH was elevated in those samples warmed repeatedly, but remained within the normal range. These data indicate the potential for further investigation utilizing properly controlled microwave energy for in-line blood and fluid warming.     

An innovative simple technique of blood conservation in adult patients with tetralogy of Fallot and severely raised hemoglobin

The adult patients of tetralogy of Fallot often present with high hemoglobin levels. High hemoglobin and hematocrit on cardiopulmonary bypass (CPB) are associated with increased hemolysis, plasma free hemoglobin, renal dysfunction or failure, postoperative bleeding, exploration for bleeding, and increased requirement of allogeneic blood and blood products. Despite the presence of high hemoglobin and its association with adverse outcome, blood conservation is rarely practiced in these patients because of the fear of possible hemodynamic instability, and hypoxemic spell. We describe an innovative, simple technique of blood conservation for adult patients of tetralogy of Fallot with severely raised hemoglobin. With this technique, hemoglobin can be normalized on CPB; moreover, there is no fear of hypoxemic spell or hemodynamic instability. Furthermore, the blood conserved is readily available for transfusion in the perioperative period, if needed.     

The effects of preoperative autologous donations on perioperative blood levels

The purpose of this study was to evaluate the blood levels of patients preparing for total knee arthroplasty (TKA) who were enrolled in a preoperative autologous donation program. The charts and hospital records of 70 consecutive patients who underwent primary unilateral TKA between 2000 and 2002 were retrospectively reviewed. Study participants were instructed to donate one unit of blood approximately 4 weeks prior to surgery. Predonation and preoperative hemoglobin levels were assessed throughout the study and transfusion requirements were recorded. Transfusions were administered only when warranted by clinical symptoms. The mean initial (predonation) hemoglobin concentration was 14.1 g/dL. The mean number of days donations were made prior to surgery was 13 +/- 3.3 days. Prior to surgery, the average hemoglobin concentration dropped to 12.8 g/dL. Fifty (71%) patients had a hemoglobin value > 13.0 g/dL prior to their autologous donation, but only 30 (43%) patients had blood levels > or = 13.0 g/dL following blood donation. Postoperatively, the mean hemoglobin concentration in the recovery room was 11.6 g/dL and dropped to a nadir of 10.8 g/dL on postoperative day 3. Overall, 91% of patients required autologous blood transfusion following TKA but no patients required allogeneic blood transfusions. Preoperative autologous donation was associated with a decrease in preoperative hemoglobin levels and with a high rate of autologous transfusion based on clinical symptoms of postoperative anemia.     

Intraoperative autotransfusion in primary hip arthroplasty: A randomized comparison with homologous blood

To study the quality and effect of blood produced by the cell saver compared with homologous blood in total hip arthroplasty, 40 patients were randomly divided into two groups. One group received autologous blood using the cell saver, whereas the second group served as a control, and received homologous bank blood. Hematologic and coagulation parameters of the patients were assessed both preoperatively and postoperatively. Samples from the autologous and the homologous blood were obtained before reinfusion, and were assessed as regards hematologic and biochemical parameters. The autologous blood satisfied all the intraoperative transfusion requirements of the autologous group and 75 percent of the total transfusion requirements. The operative and postoperative blood losses—hence, the total blood loss-were less in the autologous than in the control group. The autologous blood had a high hemoglobin, white blood cell, and plasma hemoglobin content and MCV compared with the homologous blood. Postoperatively, there were no differences as regards the hematologic parameters studied. There was no evidence of intravascular hemolysis in the autologous group. Postoperatively, in both groups, AT Ill, plasminogen, and protein C decreased. Other coagulation parameters were within normal limits in both groups. Intraoperative autotransfusion is safe and effective, and should be considered in hip arthroplasty to reduce the risks associated with homologous blood transfusion.     

Contegra pulmonary valved conduits cause no relevant hemolysis

BACKGROUND: Contegra is a bovine jugular vein graft for pediatric RVOT reconstruction. Regular blood draws belong to a (controlled phase I) study protocol aiming at FDA-admission that included the first 60 patients. After 3.3 years we found not a single case of clinically relevant hemolysis and looked for reasons to eliminate this traumatic procedure from the protocol. METHODS: Age of the patients ranged from 2 days to 17.4 years (median 1.6 years). Out of them 26 were males and 34 were females. Blood samples were taken before implant, before discharge, 1, 3, 6, and then every 6 months after implantation. Haptoglobin, free hemoglobin, reticulocytes, and hemoglobin were determined. We evaluate a total follow-up time of 132.6 years and 365 blood probes. We normalized the values to standard deviations, built a score (1 point for each value pointing toward hemolysis with at least two standard deviations) to compare divergent findings, and compared pre- and postoperative values. Finally, we analyzed the role of three patients with coexisting mechanical valve prostheses. RESULTS: High free hemoglobin was not associated with lower hemoglobin, indicating no chronic hemolysis. A high RVOT gradient as possible shear stress indicator was not associated with low haptoglobin or higher score values. All parameters turned into or toward normal ranges and showed less hemolysis than preoperatively. A mean of 1.1 parameters indicated (clinically irrelevant) hemolysis after 6 months or later. Haptoglobin was significantly lower in mechanical valve patients. CONCLUSION: There is no hint that Contegras cause hemolysis.     

Intraoperative autotransfusion in primary hip arthroplasty. A randomized comparison with homologous blood.

To study the quality and effect of blood produced by the cell saver compared with homologous blood in total hip arthroplasty, 40 patients were randomly divided into two groups. One group received autologous blood using the cell saver, whereas the second group served as a control, and received homologous bank blood. Hematologic and coagulation parameters of the patients were assessed both preoperatively and postoperatively. Samples from the autologous and the homologous blood were obtained before reinfusion, and were assessed as regards hematologic and biochemical parameters. The autologous blood satisfied all the intraoperative transfusion requirements of the autologous group and 75 percent of the total transfusion requirements. The operative and postoperative blood losses--hence, the total blood loss--were less in the autologous than in the control group. The autologous blood had a high hemoglobin, white blood cell, and plasma hemoglobin content and MCV compared with the homologous blood. Postoperatively, there were no differences as regards the hematologic parameters studied. There was no evidence of intravascular hemolysis in the autologous group. Postoperatively, in both groups, AT III, plasminogen, and protein C decreased. Other coagulation parameters were within normal limits in both groups. Intraoperative autotransfusion is safe and effective, and should be considered in hip arthroplasty to reduce the risks associated with homologous blood transfusion.     

Haptoglobin therapy for possible prevention of renal failure following thermal injury: a clinical study

Hemolysis does not necessarily result in acute renal failure in severely burned patients, but free serum hemoglobin may play some important role in the development of renal damage. This controlled study of the effects of haptoglobin administration in severely burned patients presenting with hemoglobinuria produced the following results: As long as free hemoglobin was present in the plasma, free serum haptoglobin remained undetectable. Free serum hemoglobin dropped rapidly after haptoglobin treatment, whereas the free serum hemoglobin levels in control patients remained unchanged for at least 12 hours. The time required for macroscopic hemoglobinuria to clear showed a statistically significant difference between the haptoglobin-treated patients and the control patients. Some patients among the haptoglobin-treated group had prolonged hemolysis and hemoglobinuria which might have cleared with additional doses of haptoglobin.     

Hemolysis with rapid transfusion systems in the trauma setting.

OBJECTIVE: Rapid infusion system allows rapid infusion of resuscitation fluids at body temperature in trauma patients. Packed red blood cells are subjected to high external pneumatic pressure (up to 300 mm Hg) and rapid infusion rates through a 170-microm filter. This study was conducted to outline hemolysis that may occur in the setting of massive transfusion (> 10 units). METHODS AND MATERIALS: Measurements of various parameters were made before and after infusion of 17 units of outdated (38-82 d) packed red blood cells through a Level 1 Rapid Infuser, including lactate dehydrogenase (LDH), potassium, plasma hemoglobin, hematocrit and total hemoglobin. Hemolysis, expressed as a percentage, was calculated from these parameters. RESULTS: Hemolysis observed in this experiment ranged from near 0 to 0.05%. All the units had plasma potassium concentrations of 15 mmol/L or more. CONCLUSION: Transfusion of 17 units with the Level 1 Rapid Infuser did not cause a clinically significant amount of hemolysis.     

Effectiveness of postoperative autologous blood transfusion after knee replacement surgery and influence of preoperative hemoglobin level

OBJECTIVE: To evaluate the effectiveness of postoperative autologous blood transfusion on reducing the need for allogenic transfusion during recovery from total knee arthroplasty until hospital discharge, and to determine whether effectiveness is related to preoperative hemoglobin level. MATERIAL AND METHODS: Retrospective study of patients undergoing surgery at Hospital Jerez de la Frontera, Spain, in 2003, assessing the association between postoperative autologous blood transfusion, preoperative hemoglobin, and allogenic transfusion requirements. RESULTS: A total of 107 patients were studied. Eighty-three received autologous blood transfusions after surgery and 15 (14.02%) required allogenic transfusion. The rate of allogenic transfusion was higher in association with hemoglobin levels exceeding 13 g x dL(-1) (P=0.003) and it was lower in patients who received autologous blood transfusions (P=0.046). In patients who received autologous transfusion, preoperative hemoglobin level and risk of allogenic transfusion were unrelated. When autologous transfusion was not given, allogenic transfusion risk was higher when hemoglobin concentration was less than 13 g x dL(-1) (P=0.0008). Autologous transfusion had a significant effect when hemoglobin level was less than 13 g x dL(-1) (P=0.002) but did not affect the rate of transfusion when hemoglobin was 13 g x dL(-1) or more. CONCLUSIONS: Autologous blood transfusion is effective for reducing the need for allogenic transfusion after knee replacement surgery, particulary when a patient's hemoglobin level is less than 13 g x dL(-1).     

The importance of glucose for the Escherichia coli mediated citrate depletion in synthetic and human urine

OBJECTIVE: Escherichia coli has previously been shown to reduce urine citrate and influence urine pH. In this study the influence of glucose on the E. coli mediated citrate decrease has been investigated. MATERIAL AND METHODS: In synthetic urine, a glucose concentration of > or = 1 mmol/l was a prerequisite for bacteria to grow and lower citrate. At glucose concentrations > or = 5 mmol/l an E. coli mediated pH decrease correlated to urine glucose was observed. RESULTS: In human urine, variations in urine glucose influenced the citrate decrease and addition of glucose accelerated the E. coli mediated citrate decrease, which in certain urines could be very pronounced. CONCLUSIONS: Citrate has a pronounced effect on the activity product of calcium oxalate and calcium phosphate and the E. coli mediated decrease in urine citrate may be involved in the formation of urinary tract stones and catheter encrustations.     

Perioperative change of ionized magnesium concentration--effect of blood transfusion

In order to evaluate the effect of intra-operative blood transfusion on post-operative decrease of ionized Mg (Mg2+), we performed following studies. 1) We measured ionized Mg (Mg2+), total Mg, ionized Ca (Ca2+), total Ca and citrate before and after operation in 70 patients. 2) We evaluated the effect of citrate on Mg2+ and Ca2+ in vitro. 3) We also measured these values during blood transfusion in 8 patients. There was no significant difference between post-operative Mg2+ of 45 patients without blood transfusion (0.49 +/- 0.07 mmol.l-1, % decrease from pre-operative value was 13.4 +/- 9.2%; mean +/- SD), and that of 25 patients with blood transfusion (0.48 +/- 0.09 mmol.l-1, 17.9 +/- 10.2%). Mean value of post-operative citrate concentration of patients with blood transfusion was 0.15 +/- 0.11 mmol.l-1, and this value decreased Mg2+ about 2% in in vitro study. During blood transfusion, Mg2+ (0.41 +/- 0.05 mmol.l-1) and ionized % (54.5 +/- 8.3%) decreased significantly just like Ca2+ with elevated citrate concentration (0.95 +/- 0.59 mmol.l-1). In conclusion, intra-operative blood transfusion had minor effect on the post-operative decrease of Mg2+, and the major cause was thought to be the dilution of extracellular fluid by Mg-free fluid administered during operation.     

The effect of erythropoietin on allogeneic blood requirement in patients undergoing elective liver resection: a model simulation

We investigated whether recombinant human erythropoietin (rHuEPO) administration would reduce red blood cell (RBC) transfusion requirements in patients undergoing elective liver resection. We retrospectively investigated 200 patients undergoing elective liver resection. Factors likely to predict perioperative RBC transfusion were studied using a logistic regression analysis. A mathematical model was used to simulate RBC transfusion requirements if (a). transfusion thresholds had been predefined at a hemoglobin concentration of 7-8 g/dL, (b). preoperative hemoglobin concentrations had been increased to 15 g/dL by rHuEPO administration in patients with preoperative hemoglobin concentration in the range 10-13 g/dL, and (c). both interventions had been used. A cost/benefit evaluation of rHuEPO administration formed part of this simulation. RBC transfusion was correlated with major and median liver resection, total liver vascular exclusion, and a combined nonhepatic abdominal surgery but was not correlated with a preoperative hemoglobin concentration in the range 10-13 g/dL. Adherence to a small transfusion threshold or rHuEPO administration alone would have resulted in a slight reduction in transfusion requirements and transfusion rates for the whole population. However, the two interventions in combination would have significantly reduced both variables. One-hundred-eighteen patients undergoing median and major liver resection received 92% of RBC transfused. Sixty-six of these 118 patients had preoperative hemoglobin concentrations in the range 10-13 g/dL and could have received rHuEPO before surgery. rHuEPO alone would have avoided the transfusion of 63 RBC packs of 203 in this subgroup and 12 transfused patients of 31 (P = 0.02). rHuEPO administration to these 66 patients would have cost 186000 Euro. The 63 RBC saved would have cost 10,710 Euro. IMPLICATIONS: A mathematical model simulation suggests that the routine preoperative administration of erythropoietin to patients scheduled for major and median liver resection presenting with a preoperative hemoglobin concentration in the range 10-13 g/dL could reduce blood transfusion requirements. However, the cost/benefit ratio warrants consideration.