Factors affecting the efficiency of collection of CD34-positive peripheral blood cells by a blood cell separator

BACKGROUND: The yield of CD34-positive cells obtained from an apheresis procedure is determined, in part, by the efficiency of collection. Optimization of the efficiency of CD34-positive peripheral blood cell collection requires identification of predictive factors. STUDY DESIGN AND METHODS: Demographic, stem cell collection, mobilization, and disease-related measures from autologous and allogeneic donors undergoing 252 progenitor cell apheresis procedures were retrospectively reviewed. Statistical relationships between CD34 collection efficiency and the various measures were determined by correlation and multiple linear regression analysis. RESULTS: CD34 collection efficiency inversely correlated with the peripheral white cell count, hematocrit, and serum albumin concentration (R2 = 0.29). White cell count was the single best predictor of CD34 efficiency (R2 = 0.19). Donor groups with cytopenias (patients vs. normal donors; increased cycles of prior chemotherapy; bone marrow involvement; chemotherapy plus growth factor mobilization) had higher collection efficiencies. Only 29 percent of the variability in the data could be attributed to white cell count, hematocrit, and albumin concentration. The majority of the remaining variability was due to unexplained differences between donors. CONCLUSION: CD34 collection efficiencies show considerable variation. Higher peripheral white cell counts, hematocrits, and/or albumin concentrations result in decreased CD34 collection efficiency, but most of the variability in the data is not accounted for by these three factors.     

Quality assessment of intraoperative blood salvage and autotransfusion

Intraoperative blood salvage and autotransfusion are commonly used to minimize exposure to banked blood. Although this technique has been used widely for years, data vary regarding the quality of autotransfused blood. Salvaged blood may contain plasma, residual heparin, and free hemoglobin released from damaged cells. All of these factors may contribute to the adverse sequelae sometimes seen with autotransfusion. For these reasons, we have monitored autotransfused blood to assess its quality. Intraoperative blood salvage was used during most cardiac procedures and at the discretion of the surgeon in other specialties. Blood was collected through a double lumen catheter that was anticoagulated with heparin, filtered, centrifuged, and washed with saline. A sample of the blood was removed for analysis, which included hematocrit, heparin assay, fibrinogen, and free hemoglobin levels. Over a 6-year period, 1593 patients had intraoperative blood salvage with quality assessment. The majority of patients underwent cardiac operations (941 patients, 59%), whereas 243 had orthopedic (15%) and 208 had vascular (13%) procedures. Additionally, there were 127 pediatric patients (8%) and 74 miscellaneous procedures (5%). The highest average yield of salvaged blood was during vascular procedures (1073 +/- 76 mL), whereas orthopedic cases had the lowest yield (378 +/- 19 mL) and hematocrit (39%). There was minimal residual heparin activity, even in patients requiring systemic anticoagulation (0.3 to 0.5 units/mL). Patients undergoing pediatric procedures had the lowest concentration of free hemoglobin (476 mg/L), whereas all adult patients had higher free hemoglobin levels, especially vascular operations (990 mg/L). Intraoperative salvaged blood has minimal heparin activity, even in procedures requiring systemic anticoagulation. Fibrinogen, a marker of residual plasma, was undetectable in the majority of cases. These data indicate that intraoperative blood salvage generally results in a high-quality product (good hematocrit, low heparin, minimal plasma), although there are significant differences in free hemoglobin levels depending on the operative procedure.     

Mobilization of peripheral blood stem cells in children using G-CSF after carboplatin containing myelosuppressive chemotherapy

PURPOSE: Peripheral blood stem cell (PBSC) apheresis provides an alternative to autologous marrow harvest as a source of hematologic stem cells for transplantation in children with solid tumors. PATIENTS AND METHODS: Eight children with metastatic or recurrent solid tumors underwent 27 apheresis procedures. Recovery from myelosuppressive chemotherapy occurred without continuous daily growth factor support prior to mobilization. Granulocyte colony stimulating factor (G-CSF) at 16 microgs/kg/day was used to increase stem cells in the peripheral circulation. CD 34 positive cells, mononuclear cells (MNC), and CFU-GM were measured in the apheresis products. Prior chemotherapy was examined as a clinical factor that affected PBSC yield. RESULTS: A significant correlation was found between CD 34+/kg and CFU-GM/kg of the products (r = 0.758, P < 0.001). Patients receiving cumulative doses of carboplatin over 1,600 mg/m2 produced adequate MNC (1 x 10(8)/kg) but yielded significantly less CD 34+ cells or CFU-GM than those patients receiving less carboplatin. Prior doses of etoposide and ifosfamide did not effect PBSC yield. CONCLUSIONS: The mobilization technique was well tolerated, and the products obtained produced trilineage engraftment in the patients that underwent peripheral blood stem cell transplantation. Peripheral blood stem cell apheresis in children can be optimized by selection of appropriate candidates and mobilization with G-CSF after an absence of hematopoietic growth factor support.     

Safe hemoglobin or hematocrit levels in surgical patients

The terminology and fundamental aspects of the delivery, consumption, and deficits of oxygen are recalled. In chronic and acute, nonseptic states, red blood cell (RBC) transfusion is capable of increasing oxygen consumption (VO2). In acute septic states, the response of VO2 to RBC transfusion is variable and unpredictable, but attempts to increase oxygen delivery (DO2) should be made if the clinical picture raises the suspicion of a potentially lethal oxygen deficit. Therapeutic interventions raising the cardiac index to "supranormal" values in critically ill patients improve their chances of survival; and maintenance of hemoglobin or hematocrit values around 11 g/dl or 33%, respectively, is one part of such interventions. Opinions differ on the general tolerance of anemia, as witnessed by postulated "critical levels" of the hemoglobin concentration between approximately 11 and 4 to 5 g/dl or hematocrit values between 33% and 12% to 15%, respectively. The common denominator underlying these vastly different opinions is the variable behavior of several "non-Hb variables," which influence the venous oxygen tensions apart from the hemoglobin or hematocrit. Abnormalities of these non-Hb variables-typically encountered in the critically ill-increase the dependence of patients on hemoglobin or hematocrit levels that suffice to protect them against an oxygen deficit. For this reason, the "critical" hemoglobin or hematocrit is an individual value, and a generally valid "transfusion trigger" does not exist. Finally, the entity now known as silent myocardial ischemia (SMI) is a decisive factor for the tolerance of anemia. Solid clinical evidence is now available to support the concept that patients over age 40 should not, as an elective procedure, be subjected to levels < 10 g/dl or < 30%, respectively, without prior exclusion of SMI by appropriate investigations.     

Collection of allogeneic peripheral blood progenitor cells by two protocols on an apheresis system

BACKGROUND: Granulocyte-colony stimulating factor-mobilized allogeneic peripheral blood progenitor cells (PBPCs) are replacing bone marrow in transplantation for the treatment of several hematologic malignancies. The advantages of PBPCs are offset by the donor-associated disadvantages of granulocyte-colony stimulating factor side effects and the risk of apheresis-like platelet loss. STUDY DESIGN AND METHODS: For each individual, the first donation of allogeneic PBPCs by apheresis on the Spectra, using either the standard protocol Version 4.7 (45 donors, [Version 4.7]) or the AutoPBSC (60 donors, [AutoPBSC]) was compared. Between July 1995 and May 1996, all donors enrolled underwent Version 4.7 apheresis. Since May 1996, the majority of donors underwent AutoPBSC apheresis. For statistical analysis, only data from the first apheresis for each individual donor was considered for independent values. RESULTS: These results indicate a similar collection efficiency for CD34+ cells in the first apheresis of each donor (54% Version 4.7 vs. 53% AutoPBSC, p = 0.8). The apheresis time was longer with the AutoPBSC (233 min vs. 251 min, p = 0.005), whereas the loss of platelets was significantly lower (p < 0.001) with the AutoPBSC (28% vs. 19%). The mean number of CD34+ cells collected in the first apheresis component was 4.0 x 10(8) (Version 4.7) versus 3.8 x 10(8) (AutoPBSC). CONCLUSION: Both apheresis protocols collect sufficient numbers of PBSCs for allogeneic transplantation. The AutoPBSC operates in a fully automatic fashion, avoiding manual adjustment and interindividual variations. The loss of platelets is lower with AutoPBSC than with Version 4.7, but the apheresis time is slightly longer.     

Analysis of a linear peristaltic infusion device for the transfusion of red cells to pediatric patients

A linear peristaltic infusion device was evaluated for red cell (RBC) transfusion in the pediatric and neonatal setting. CPDA-1 RBC units (n = 24) divided into six groups of 4 units each underwent simulated transfusion. Blood was infused by using manufacturer-provided administration sets with either a 21-gauge needle or a 24-gauge catheter. Filters were used in two groups to evaluate the effect of negative pressure on filter function. Two groups of RBCs less than 1 week old were washed, irradiated, and infused at 5 mL per hour, by using a standard administration set, or at 10 mL per hour, by using a syringe set. Four-week-old RBCs (washed and irradiated, irradiated and filtered, filtered only, or unmanipulated) were infused at 100 mL per hour. Paired samples from 0 and 2 hours before and after infusion were analyzed for hemoglobin, hematocrit, RBC count, plasma hemoglobin, lactate dehydrogenase, potassium, alanine aminotransferase, and aspartate aminotransferase. Hausser and Nageotte hemocytometers were used to perform white cell (WBC) counts when a filter was used. By analysis of variance and percentage of change, data from 0 and 2 hours before and after infusion were compared. No clinically or statistically significant differences were seen for hemoglobin, hematocrit, or RBC count. The difference in preinfusion and postinfusion plasma hemoglobin levels in washed RBCs at 2 hours was statistically but not clinically significant (14.5 +/- 6.8 vs. 19.3 +/- 7.1 mg/dL). No clinically significant differences were noted for the remaining analytes.(ABSTRACT TRUNCATED AT 250 WORDS)     

Allogeneic peripheral blood stem cell transplantation in patients with advanced hematologic malignancies: a retrospective comparison with marrow transplantation

Allogeneic peripheral blood stem cell (PBSC) transplants from HLA-identical siblings were performed in 37 patients with advanced hematologic malignancies. Outcomes were compared to a historical group of 37 similar patients with advanced hematologic malignancies receiving bone marrow (BM) transplants from HLA-identical donors. The PBSC group and historical BM group were well matched for diagnosis, disease stage, age, and graft-versus-host disease (GVHD) prophylaxis. Patients received PBSC transplants between 1993 to 1995 while BM patients were treated between 1989 to 1994. Engraftment, measured by the time to reach a peripheral neutrophil count > 500/L and platelet count > 20,000/microL without transfusions, occurred on days 14 and 11 in the patients transplanted with PBSC compared to days 16 and 15 in the patients receiving BM (P = .00063, .00014). The PBSC group required a median of 8 U of red blood cells and 24 U of platelets compared to 17 U of red blood cells and 118 U of platelets for BM transplant recipients (P = .0005, .0001). The estimated risks of developing grades 2 to 4 acute GVHD were 37% for the PBSC group and 56% for the BM group (P = .18), while the estimated risks of grades 3 to 4 acute GVHD were 14% for the PBSC group and 33% for the BM group, P = .05). Chronic GVHD occurred in 7 of 18 evaluable patients receiving PBSC and 6 of 23 evaluable patients receiving BM, P = .5. The estimated risks of transplant-related mortality at 200 days were 27% versus 45% (P = .33) relapse were 70% versus 53% (P = .27) and of overall survival were 50% and 41% (P = .39) for patients transplanted with PBSC or BM, respectively. This retrospective comparison suggests that compared to marrow transplantation from HLA-identical donors, allogeneic PBSC transplantation from HLA-identical donors is associated with faster engraftment, fewer transfusions, and no greater incidence of acute or chronic GVHD.     

Reduction of allogeneic blood transfusions after open heart operations by lowering cardiopulmonary bypass prime volume

BACKGROUND: Despite recent advances in blood conservation techniques, up to 30% to 80% of patients undergoing open heart operations require allogeneic blood transfusions. A prospective, randomized study was performed to test the effect of lowering cardiopulmonary bypass prime volume (as an additional component of an integrated blood conservation strategy) on clinical outcome and allogeneic blood transfusion. METHODS: One hundred fourteen patients undergoing open heart operations were randomized to either full prime (FP) volume (1,400 mL of Plasmalyte solution) or reduced prime (RP) volume (600 to 800 mL). The reduction of prime volume was achieved by slowly draining the cardiopulmonary bypass circuit into a cell-saving device before the initiation of bypass. Firm transfusion thresholds were observed. RESULTS: There were no significant differences between the groups with respect to baseline characteristics, body surface area, type and urgency of the procedures, perfusion technique, and hematologic profile. Mortality (FP, 1.7%; RP, 0%; p approximately 1.0) and overall morbidity (FP, 28.1%; RP, 22.8%; p = 0.53) were similar. However, transfusion requirements were significantly lower in the RP group: total donor exposure, 3.8 +/- 10.1 versus 1.0 +/- 2.4 units (p = 0.044); percentage of patients transfused, 54% (n = 31) versus 35% (n = 20) (p = 0.036). Twenty-four-hour chest tube drainage was similar: 455 +/- 223 mL for FP versus 472 +/- 173 mL for RP (p = 0.66). The lowest hematocrit on bypass was significantly higher in the RP group: 29.3% +/- 4% versus 26.3% +/- 5.3% (p = 0.009). CONCLUSIONS: Lowering cardiopulmonary bypass prime volume resulted in a significant decrease in allogeneic blood product use. Because postoperative 24-hour chest tube drainage was similar in both groups, and hematocrit during bypass was higher in the RP group, the reduction in allogeneic blood transfusions appears to be related to a decrease in prime-induced hemodilution. This technique is effective, simple, and safe. It therefore should be strongly considered for patients undergoing operations using normothermic or near-normothermic cardiopulmonary bypass who are at high risk for allogeneic blood transfusion.     

Effects of gamma irradiation on red cells from donors with sickle cell trait

BACKGROUND: Transfusion-associated graft-versus-host disease can be prevented by gamma irradiation of blood components. Red cells (RBCs) from sickle cell disease patients may exhibit oxidative changes of RBC membranes due to the instability of hemoglobin (Hb) S. Persons with sickle cell trait are eligible to donate blood, and 35 to 45 percent of their total Hb is Hb S. The effect of gamma irradiation on RBCs from such persons is of interest. STUDY DESIGN AND METHODS: RBCs from 12 donors with sickle cell trait (Hb AS) and from 12 with normal Hb (Hb AA) were studied. Each of the 24 RBC units was divided equally into two transfer bags via a sterile connecting device. One bag from each RBC unit received a 2500-cGy dose of gamma irradiation at its mid-plane and was stored at 4 degrees C; the second set of bags was stored without irradiation. For RBCs from 6 donors with Hb AS and 6 donors with Hb AA, units were irradiated on Day 7 and studied on Day 35 of storage (Group 1). For the RBCs from the other 6 donors with Hb AS and the other 6 donors with Hb AA, units were irradiated on Day 28 and studied on Day 42 of storage (Group 2). RESULTS: For Group 1 and Group 2, plasma potassium and plasma Hb concentrations were significantly higher and RBC ATP concentrations were slightly lower in the irradiated units than in the nonirradiated units. In Group 1 and Group 2, there were no significant differences in the plasma potassium or RBC ATP concentrations in either the irradiated or the nonirradiated units of RBCs from donors with Hb AS and donors with Hb AA. Plasma Hb concentrations were consistently lower in the units from donors with Hb AS, whether or not they were irradiated. However, in both groups, proportionally similar changes in plasma Hb concentration were detected when the irradiated Hb AS and Hb AA units were compared to nonirradiated Hb AS and Hb AA units. CONCLUSION: Gamma irradiation of RBCs from donors with Hb AS or with Hb AA resulted in comparable changes in plasma potassium, RBC ATP, and plasma Hb concentrations, although donors with Hb AS had lower plasma Hb. RBCs from donors with Hb AS subjected to 2500 cGy of gamma irradiation did not evidence a storage lesion greater than that seen in RBCs from donors with Hb AA.     

Efficacy and onset of action of fluticasone propionate aqueous nasal spray on nasal symptoms, eosinophil count, and mediator release after nasal allergen challenge in patients with seasonal allergic rhinitis

In order to determine if peripheral blood stem cells (PBSC) collected after priming with G-CSF in AML in first complete remission (CR) can be used for autologous transplantation and to evaluate the efficacy of early intensification therapy as in vivo purging, we studied 35 consecutive patients with AML in first CR. After standard induction and consolidation chemotherapy, 24 of them were treated with one (10 patients) or two (14 patients) cycles of high-dose cytarabine plus etoposide prior to PBSC collection. G-CSF was used as the priming agent. Of the 35 patients scheduled for peripheral blood stem cell transplantation (PBSCT), three relapsed before transplantation, and the 32 remaining underwent PBSCT. High-dose therapy consisted of either total body irradiation plus cyclophosphamide or busulphan plus cyclophosphamide. The median number of CD34+ cells infused was 3.24 x 10(6)/kg (range 0.15-14). The median times to reach a PMN count of 0.5 x 10(9)/l and a platelet count of 50 x 10(9)/l were 12 (8-28) and 30 (11-345) days, respectively. There was no transplant-related mortality. Twelve patients relapsed between 2 and 21 months post-PBSCT. With a median follow-up of 28 months, actuarial disease-free survival (DFS) is 52.41 +/- 9% in the intent-to-treat group and 57.4 +/- 9.8% in patients who underwent PBSCT. The probability of DFS is significantly higher for patients who receive early intensification therapy prior to both PBSC collection and PBSCT as compared with patients that do not: 68.8 +/- 10.27% vs 35.5 +/- 12.6%, P = 0.0418. These results indicate the feasibility of PBSCT in AML using G-CSF-mobilized PBSC. The use of intensification treatment as 'purging in vivo' prior both to collection of PBSC and PBSCT significantly reduces the risk of relapse in this group of patients.     

Avoidance of homologous blood transfusion despite extreme blood loss

We report the case of a 22-year-old woman who underwent two-step scoliosis surgery without allogeneic transfusion, although the intraoperative blood loss (3500 ml) during the first procedure was higher than the calculated blood volume (3250 ml). Preoperatively the patient had donated four units of autologous blood. Intraoperatively blood-saving methods were combined. During the first operation acute normovolemic hemodilution (target hemoglobin 9.0 g/dl) was applied and during the second operation controlled hypotension (systolic blood pressure 80 mmHg). Intraoperative auto-transfusion was used in both procedures. During the first operation severe normovolemic anemia (minimal hemoglobin 3.5 g/dl) was accepted while the patient was ventilated with FiO2 1.0. The hemoglobin concentration was 8.6 g/dl after the first procedure and had increased to 11.6 g/dl 4 weeks after the second procedure. No severe complications occurred during the postoperative phase. This case report shows that also in surgical procedures with extreme blood loss any allogenic transfusion can be avoided by the combination of blood-saving methods, acceptance of low intraoperative transfusion trigger and ventilation with 100% oxygen.     

Allogenic peripheral blood stem cell (PBSC) transplantation in two patients with graft failure

Allogenic peripheral blood stem cells (PBSC) were used for graft failure after BMT in two patients. These PBSC were mobilized by G-CSF in the same donors, harvested and given without reconditioning to the patients. In one patient, PBSC with a very high T cell number were given unprocessed, in the other patient, CD34+ cells were positively enriched due to a 2-antigen difference. None of the patients had hyperacute GVHD. Trilineage engraftment was seen after 13 days. Acute GVHD grade II to III developed on days +31 in patient 1 and +16 in patient 2, involving predominantly gut and liver, but sparing the skin. Thus, allogeneic PBSCT for graft failure did not cause hyperacute GVHD even with very high T cell numbers in patient 1, and graft failure with CD34 selected PBSC was successfully reversed even with a low number of T cells in patient 2.     

A novel antithrombin gene mutation: slippage and mispairing as a mechanism of genetic disease

Treatment options for acute leukemia relapsing after allogeneic BMT include conventional chemotherapy or a second transplant; however, results are rather discouraging, the first option being associated with poor survival and the second with a high mortality rate. More recently, donor leukocyte infusion (DLI) from the original donor has been used for relapsed patients in an attempt to induce a graft-versus-leukemia (GVL) effect. This procedure is partially devoid of the toxicity inherent to a second BMT. At our Institution, a 36-year-old patient with biphenotypic AML in second complete remission after relapse following allogeneic BMT was treated with peripheral blood stem cell (PBSC)-enriched donor leukocytes, obtained after in vivo priming with rhG-CSF. The patient experienced extensive cGVHD but developed a testicular relapse while in full hematologic remission. After irradiation of the sanctuary site he remains free of disease, still with chronic GVHD, 21 months after bone marrow relapse. This case suggests that immunologically privileged sites are inaccessible to GVHD/GVL effect. This should be considered when planning salvage transplants procedures in patients at risk for extramedullary involvement.     

Neocytoapheresis in the treatment of polycythemia vera

In absence of thrombocytosis, periodic bloodlettings represent the elective therapy of polycythemia vera. In the present study we tested if neocytoapheresis, a method able to remove large quantities of younger, and then bigger red cells could represent an alternative therapeutic choice in these patients. We found that the employment of neocytoapheresis produced a remarkable delay in the time of procedures with a mean interval of 100 +/- 55 days. The mean value of hematocrit before neocytopheresis is resulted statistically different in comparison with the hematocrit after the procedure (p = 0.0001). The reticulocyte count is resulted higher in apheresis product in comparison with the blood control measured before procedure (p = 0.0001). In the same way, the mean corpuscular volume in the collection bags was higher than the volume measured before neocytoapheresis (p = 0.0095). We did not find any variation about the mean values of white blood cells and platelets before and after neocytoapheresis in the patients examined. These preliminary data seem to underline a better withdrawal of big size cells by this technique suggesting the efficacy of neocytoapheresis in the treatment of polycythemia vera.     

Proliferative activity and loss of function of tumour suppressor genes as ''biomarkers'' in diagnosis and prognosis of benign and preneoplastic oral lesions and oral squamous cell carcinoma

Patients with hematologic malignancy or severe aplastic anemia after myeloablative chemo- and radiotherapy were given granulocyte colony-stimulating factor (G-CSF)-mobilized, cryopreserved allogeneic peripheral blood stem cells (PBSCs) from 15 healthy donors who were either human leukocyte antigen (HLA)-matched siblings (n = 13) or haploidentical offspring (2). Polymerase chain reaction-amplified short tandem repeat genotyping was used for early confirmation of donor engraftment after PBSC transplantation (PBSCT). A standard cyclosporine A/methotrexate combination was used to prevent acute graft-versus-host disease (GVHD). All donors, including one in the third trimester of pregnancy, tolerated G-CSF administration and 3-day PBSC harvesting procedures well. Engraftment was prompt for all patients; it was verified using a panel of 12 human polymorphic short tandem repeat loci from bone marrow as early as 7 days posttransplantation. This status was maintained until relapse, when mixed chimerism was detected using the polymerase chain reaction. A minimum resurgence of recipient cells to 1% of the population was required to detect chimerism. The median times to recovery of the absolute neutrophil count to greater than 0.5 x 10(9)/L and the sustained platelet count to greater than 20 x 10(9)/L without transfusion were 10 and 12 days after PBSCT, respectively. Six patients experienced acute GVHD, Grade I in two patients and Grade II in four, including two HLA-haploidentical recipients. Chronic GVHD was noticed in three of the 11 patients who were followed for at least 100 days after PBSCT. Ten patients were still alive at the latest follow-up and have been disease free for a median of 278 days (range 60-671). Five patients died from causes other than graft failure: three from leukemia relapse and two from transplant-related complications. The results confirm that G-CSF can be safely administered to healthy donors and that engraftment after allogeneic PBSCT is fast and durable. Complete chimerism can be detected early by genomic analysis. PBSCT may offer an alternative to bone marrow transplantation.     

Clinical toxicity and laboratory effects of granulocyte-colony-stimulating factor (filgrastim) mobilization and blood stem cell apheresis from normal donors, and analysis of charges for the procedures

BACKGROUND: Apheresis of granulocyte-colony-stimulating factor (filgrastim)-mobilized blood stem cells from normal donors is now being used in place of a marrow harvest in transplantation. How the adverse effects of and charges for this procedure compare with those of the standard marrow harvest is not known. STUDY DESIGN AND METHODS: Forty consecutive normal subjects who received filgrastim 96 micrograms/kg) subcutaneously twice daily for 4 to 6 days in preparation for apheresis were monitored prospectively by clinical and laboratory evaluation. RESULTS: Sixty-two percent of the subjects required oral analgesics. None discontinued filgrastim prematurely. Bone pain (82%), headache (70%), fatigue (20%), and nausea (10%) were reported. Filgrastim caused a mean eightfold increase in neutrophil counts, a mean twofold increase in lymphocyte counts, a mean twofold rise in alkaline phosphatase and lactate dehydrogenase levels, and minor changes in serum potassium, magnesium, and uric acid. Adverse events and laboratory effects resolved within 7 days after apheresis. No apheresis stem cell donor required transfusion or hospitalization, and only one required an additional clinic visit after completion of apheresis. By comparison, a retrospective analysis of 33 normal marrow donors demonstrated that all received transfusion(s), 3 were hospitalized, 3 required additional clinic visits after the marrow harvest. The median total charges related to the two procedures were comparable (p = 0.43), although the charges were significantly lower for donors requiring only one apheresis procedure (p = 0.002). CONCLUSION: Filgrastim mobilization and apheresis of blood stem cells constitute a safe, well-tolerated, and comparable or less expensive alternative to the traditional marrow harvest.     

Preload and incident angle independent index of left ventricular contractility determined by continuous wave Doppler echocardiography

BACKGROUND: Incubating blood with phosphoenolpyruvate decreases hemoglobin oxygen affinity (HOA). This study compared transfusion with phosphoenolpyruvate-treated blood and conventionally stored blood on oxygen consumption in acutely anemic dogs. METHODS: Dogs underwent isovolemic hemodilution (hematocrit = 10%). After 1 hour they were transfused to a hematocrit of 18% with control or phosphoenolpyruvate treated blood. Cardiac output, co-oxymetry, and hemoglobin P50 measurements allowed calculation of oxygen consumption during anemia, and posttransfusion. RESULTS: Hemodilution doubled cardiac output. Transfusion with phosphoenolpyruvate-treated blood allowed greater O2 consumption than control (8.31+/-2.1 and 3.73+/-0.11 cc/kg/mm). There were no differences in arterial or venous PO2 or pH; there were marked differences in HOA, measured by posttransfusion P50 (21+/-3 versus 47+/-4), and mixed venous O2 saturation. CONCLUSIONS: Decreased HOA results in increased O2 consumption in dogs subjected to anemic hypoxia. Phosphoenolpyruvate-treated blood provides increased oxygen consumption at a similar hematocrit when compared with untreated banked blood.     

CD34 positive blood cells for allogeneic progenitor and stem cell transplantation

The transplantation of allogeneic peripheral blood progenitor cells (PBPC) provides complete and sustained hematopoietic and lymphopoietic engraftment. In healthy donors, large amounts of PBPC can be mobilized with hematopoietic growth factors. However, the high content of immunocompetent T-cells in apheresis products may expose recipients of allogeneic PBPC to an elevated risk of acute and chronic graft-versus-host disease. Thus, the use of appropriate T-cell reduction, but not depletion might reduce this risk. The hazards of graft rejection and a higher relapse rate can be avoided by maintaining a portion of the T-cells in the graft. The positive selection of CD34+ cells from peripheral blood preparations simultaneously provides an approximately 1000-fold reduction of T-cells. These purified CD34+ cells containing committed and pluripotent stem cells are suitable for allogeneic transplantation and can be used in the following instances: 1. As hematopoietic stem and progenitor cell transplantation instead of bone marrow cells, from HLA-identical family donors; 2. for increasing the stem cell numbers from HLA-mismatched or three HLA-loci different family donors in order to reduce the incidence of rejection but without increasing the T-cell number; 3. boosting of poor marrow graft function with stem cells from the same family donors; 4. transplantation from volunteer matched unrelated donors; 5. split transplantation of CD34+ and T-cells; 6. addition of ex vivo expanded CD34+ cells to blood cell or bone marrow transplantation; 7. generation of antigen specific immune effector cells and antigen presenting cells for cell therapy.     

An algorithm to optimize perioperative blood management in surgery

Innovation in surgical blood management has been fueled by patients' perceptions of the risks associated with allogeneic blood transfusions and by surgeons' attitudes toward the use of allogeneic blood. The challenge is to determine the best blood management strategy to implement in the individual patient, particularly in patients with anemia who are at high risk of allogeneic blood transfusion. An algorithm to estimate safe blood loss based on individual patient parameters has been developed. The algorithm uses patient weight, gender, and preoperative hematocrit level to derive the volume of blood loss that can be tolerated while maintaining a target postoperative hematocrit level. Because the margin of safe blood loss can be anticipated, the most appropriate blood conservation option(s) can be implemented and perioperative blood management can be optimized.     

Epoetin alfa. A bloodless approach for the treatment of perioperative anemia

Under normal physiologic conditions the level of circulating red blood cells is regulated precisely by the glycoprotein erythropoietin. In major elective surgery, patients who are participating in preoperative autologous blood donation or who are anemic may not have the capacity to manufacture sufficient red blood cells in response to increases in endogenous erythropoietin that is sufficient to avoid perioperative allogeneic blood transfusion. In these patients pharmacologic doses of recombinant human erythropoietin (Epoetin alfa) have been shown to accelerate erythropoiesis, thereby increasing preoperative red blood cell production, hematocrit level, and hemoglobin concentration and reducing exposure to allogeneic blood transfusion. In four large multicenter studies, 869 patients undergoing major elective surgery were treated with a daily regimen (300 or 100 IU/kg x 14 or 15 doses) or a weekly regimen (600 IU/kg x 4 doses) of subcutaneous Epoetin alfa beginning either 2 or 3 weeks before surgery, respectively. Although all Epoetin alfa regimens were effective at accelerating erythropoiesis and increasing red blood cell production, the weekly regimen was the most patient friendly, cost effective regimen for treating preoperative anemia and minimizing patient risk of allogeneic blood transfusion.