Association of Hematocrit and Red Blood Cell Transfusion with Outcomes in Infants Undergoing Norwood Operation.

The objective of this study was to investigate the association between red blood cell (RBC) transfusion and hematocrit values with outcomes in infants undergoing Norwood operation. This study included infants ≤2 months of age who underwent Norwood operation with either a modified Blalock-Taussig shunt or a right ventricle-pulmonary artery shunt. Demographics, preoperative, operative, daily laboratory data, and postoperative variables were collected. The primary outcome measures evaluated included mortality, ICU length of stay, length of mechanical ventilation, and days to chest closure. The secondary outcome measures evaluated included lactate levels, estimated glomerular filtration rate, and inotrope score in the first 14 days after heart operation. Cox proportional hazard models were fitted to study the probability of study outcomes as a function of hematocrit values and RBC transfusions after operation. Eighty-nine patients qualified for inclusion. With a median hematocrit of 46 (IQR 44, 49), and a median RBC transfusion of 92 ml/kg (IQR 31, 384) in the first 14 days after operation, 81 (91 %) patients received RBC transfusions. A multivariable analysis adjusted for risk factors, including the age, weight, prematurity, cardiopulmonary bypass and cross-clamp time, and postoperative need for nitric oxide and dialysis, demonstrated no association between hematocrit and RBC transfusion with majority of study outcomes. This single-center study found that higher hematocrit values and increasing RBC transfusions are not associated with improved outcomes in infants undergoing Norwood operation.

Hematopoietic stem cell mobilization: a clinical protocol.

Autologous hematopoietic stem cell transplantation is the standard treatment for a wide variety of malignancies. At present, most hematopoietic progenitor/stem cell (HPC) collections are collected from the peripheral blood via leukapheresis following chemotherapy and/or growth factor-mediated mobilization. Most mobilization regimens consist of chemotherapy followed by one or more growth factors such as G-CSF, GM-CSF, or plerixafor. Occasionally a subset of patients will prove unable to mobilize effectively and will not collect at least 2.0 × 310(6) CD34+ cells/kg, the number of HPC currently considered to be appropriate for transplant in order to achieve timely engraftment and recovery of hematopoiesis. When this occurs it may be necessary to either remobilize, possibly with a different method, or to do a marrow harvest. Recent research has explored the benefits of using HPC outside of the oncology arena, notably in the area of cardiac regeneration following infarction, making the subject of mobilization potentially important to many areas of medicine.

Strict vs lenient criteria for elution testing: comparison of yields between two tertiary care medical centers.

In this study, 2 patient populations, using different elution strategies, were compared to evaluate eluate yields under more and less restrictive conditions. An informative eluate was defined as one in which an antibody that could be clinically significant was detected in the eluate but was not detectable in the plasma at the time of elution testing. The results for 160 direct antiglobulin tests (DATs) and 160 elution studies were evaluated in 71 patients at the adult hospital (lenient criteria). The results for 372 DATs and 43 elution studies were evaluated in 123 patients at the pediatric hospital (strict criteria). The yields from these eluates were 0.6% at the adult hospital (C antibody) vs 2.3% at the pediatric hospital (Jk(a) antibody). Thus, the yield of information from eluate testing is low regardless of the stringency applied to testing. However, considering the cost and time required for testing, more stringent criteria are advised.

A comparison of washed and volume-reduced platelets with respect to platelet activation, aggregation, and plasma protein removal.

BACKGROUND: Washed or volume-reduced platelets (PLTs) are occasionally requested for patients with a history of allergic or anaphylactic transfusion reactions. However, conclusive data are not available as to which method is more suitable. STUDY DESIGN AND METHODS: A direct comparison of saline-washed and volume-reduced PLTs was performed by splitting 11 units of 6-day-old apheresis PLT units. PLT activation, aggregation, plasma protein, and PLT count were determined before and after each procedure. To assess whether washing using neutral, calcium-free Ringer's acetate (NRA) would better preserve PLT function, 8 additional units of apheresis PLTs were split and were washed in saline or NRA. RESULTS: Saline washing resulted in significantly increased number of activated, P-selectin-expressing PLTs compared to volume reduction (24.2% vs. 10.3%, p = 0.001). Aggregation was also significantly reduced (-40.6% vs. -0.8%, p = 0.004). Plasma protein removal was significantly better for saline-washed than volume-reduced PLTs (96% vs. 51.1%, p < 0.001). PLT recovery was not significantly different for saline-washed versus volume-reduced PLTs (70.5% vs. 80.7%, p = 0.079). There was no difference between washing in saline or NRA with regard to PLT activation and loss of aggregation. CONCLUSIONS: PLT washing with saline or NRA significantly increases PLT activation and decreases PLT aggregability. On the other hand, volume reduction does not adequately remove plasma proteins. Therefore, PLT washing should be reserved for patients with a history of severe allergic or anaphylactic transfusion reactions. We suggest that fresher PLTs be selected to improve the functionality of washed PLTs.

Viability and engraftment of hematopoietic progenitor cells after long-term cryopreservation: effect of diagnosis and percentage dimethyl sulfoxide concentration.

BACKGROUND AIMS: We carried out a retrospective analysis of viability by diagnosis and dimethyl sulfoxide (DMSO) concentration in patients who had undergone autologous transplants using hematopoietic progenitor cells (HPC) after long-term storage (up to 17.8 years). METHODS: Viability was tested using flow cytometry for HPC that were harvested and preserved using a controlled rate freezer and 5% or 10% DMSO with human serum albumin, then stored in liquid nitrogen. Data from 262 samples were analyzed (249 myeloma patients and 13 other diagnoses): 100 consecutively thawed samples with a storage time of <1 year (all 10% DMSO), 50 consecutive samples stored for 1-4.9 years (10% DMSO), 50 samples stored for 5-9 years (5% DMSO) and all samples stored and used for transplant after >9 years (60 samples, 5% DMSO; two samples, 10% DMSO). RESULTS: No statistically significant difference in viability between the 5% DMSO and 10% DMSO groups was observed (P = 0.08), so the 1-4.9 years and 5-9 years were combined and the three groups (<1 year, 1-9 years and >9 years) were compared using an anova test. There was no difference in viability based on cryostorage period (P = 0.23) or between myeloma and other diagnoses (P = 0.45). No difference was seen in time to White blood cell (WBC) engraftment (P = 0.10) or to platelet engraftment between groups (P = 0.52). CONCLUSIONS: These data suggest that long-term storage in 5% DMSO and human serum albumin is safe.

Hemolytic disease of the fetus and newborn due to anti-Ge3: combined antibody-dependent hemolysis and erythroid precursor cell growth inhibition.

The Gerbich (Ge) antigens are a collection of high-incidence antigens carried on the red blood cell membrane glycoproteins, glycophorins C and D. Antibodies against these antigens are uncommon, and there have been only rare case reports of hemolytic disease of the fetus and newborn due to anti-Ge. In this case report, we present a neonate with severe anemia and hyperbilirubinemia due to anti-Ge3. Routine and special laboratory studies undertaken in this case suggested two mechanisms for the patient's hemolysis and persistent anemia. Antibody-dependent hemolysis was associated with early-onset hyperbilirubinemia, anemia, and a mild reticulocytosis, and inhibition of erythroid progenitor cell growth was associated with late anemia and normal bilirubin and reticulocyte values. Though rare, anti-Ge3 can be a dangerous antibody in pregnancy. Affected neonates may require intensive initial therapy and close follow-up for at least several weeks after delivery.