Donor Exposure Research Articles

Treatment of malignant fluids with OK-432, a streptococcal preparation, plus interleukin-2, or tumor necrosis factor-alpha

Massive transfusion (MT) is an empiric mode of treatment advocated for uncontrolled bleeding and massive haemorrhage, aiming at optimal resuscitation and aggressive correction of coagulopathy. Conventional guidelines recommend early administration of crystalloids and colloids in conjunction with red cells, where the red cell also plays a critical haemostatic function. Plasma and platelets are only used in patients with microvascular bleeding with PT/APTT values >1.5 times the normal values and if PLT counts are below 50 × 109/L.Massive transfusion carries a significant mortality rate (40%), which increases with the number of volume expanders and blood components transfused. Controversies still exist over the optimal ratio of blood components with respect to overall clinical outcomes and collateral damage. While inadequate transfusion is believed to be associated with poor outcomes but empirical over transfusion results in unnecessary donor exposure with an increased rate of sepsis, transfusion overload and infusion of variable amounts of some biological response modifiers (BRMs), which have the potential to cause additional harm. Alternative strategies, such as early use of tranexamic acid are helpful. However in trauma settings the use of warm fresh whole blood (WFWB) instead of reconstituted components with a different ratio of stored components might be the most cost effective and safer option to improve the patient’s survival rate and minimise collateral damage. This manuscript, after a brief summary of standard medical intervention in massive transfusion focuses on the main characteristics of various substances currently available to overcome massive transfusion coagulopathy. The relative levels of some BRMs in fresh and aged blood components of the same origin are highlighted and some myths and unresolved issues related to massive transfusion practice are discussed.In brief, the coagulopathy in MT is a complex phenomenon, often complicated by chronic activation of coagulation, platelets, complement and vascular endothelial cells, where haemolysis, microvesiculation, exposure of phosphatidyl serine positive cells, altered red cells with reduced adhesive proteins and the presence of some BRM, could play a pivotal role in the coagulopathy and untoward effects. The challenges of improving the safety of massive transfusion remain as numerous and as varied as ever. The answer may reside in appropriate studies on designer whole blood, combined with new innovative tools to diagnosis a coagulopathy and an evidence based mode of therapy to establish the optimal survival benefit of patients, always taking into account the concept of harm reduction and reduction of collateral damage.

A Program to Limit Donor Exposures to Neonates Undergoing Extracorporeal Membrane Oxygenation

Extracorporeal membrane oxygenation (ECMO) has dramatically improved the survival of neonates with life-threatening respiratory and cardiac failure. However, ECMO requires numerous transfusions with significant risks. This study evaluated the effects of changing transfusion practices and blood component management on blood donor exposures in neonatal ECMO. A 3-year retrospective chart review of all neonatal ECMO patients from December 1989 through November 1992 was undertaken. During this 3-year period, transfusion practices and blood product preparation were altered twice to reduce blood donor exposures. The use of apheresis platelets and fresh frozen plasma (FFP), and preserving the expiration date on packed red blood cells (PRBCs) through the use of a sterile connecting device, allowed multiple transfusions from individual donor components. In addition, education of the ECMO physicians was focused on standardizing and reducing transfused volumes. Sixty-four surviving neonatal patients (91.4%) were evaluated. Five patients had excessive bleeding and were excluded from analysis. The remaining 59 patients were divided into three protocols based upon the transfusion practice at the time of their ECMO course. Protocol 1 received PRBCs less than 5 days of age, volume-reduced platelet concentrates, and standard FFP units up to 24 hours after thawing. Changes in transfusion practice for protocol 2 included extended outdate for PRBCs to 10 days, and using single donor apheresis platelet aliquots. The third protocol entailed the use single donor apheresis FFP aliquots in addition to the protocol 2 changes. Total PRBC transfusion volumes (721 +/- 406 ml for protocol 1, 637 +/- 172 ml for protocol 3) and associated blood donor exposures (5 +/- 2.1 for protocol 1, 3.9 +/- 0.9 for protocol 3) did not change substantially over the reviewed period. However, FFP transfusion volumes (478 +/- 170 ml for protocol 1, 274 +/- 63 ml for protocol 3), FFP-related donor exposures (4.5 +/- 1.6 for protocol 1, 1.2 +/- 0.4 for protocol 3) and platelet-related donor exposures (4.6 +/- 3.6 for protocol 1, 2.5 +/- 1.5 for protocol 3) were reduced progressively and significantly from protocol 1 to protocol 3 (P < .01, Tukey's B test adjusted for multiple comparisons). The total number of donor exposures per patient while on ECMO was decreased from 14.1 in protocol 1 to 10.0 in protocol 2 to 7.5 in protocol 3 (P < .01). We conclude that the changes in blood bank component selection and management as well as physician practice were effective in substantially reducing ECMO-related transfusion volumes and the resulting donor exposures.

Prospective, randomized trial of the safety and efficacy of a limited donor exposure transfusion program for premature neonates

We investigated the safety and efficacy of using a single unit of packed red blood cells until its expiration date (35 days) to meet the transfusion needs of infants weighing <1.5 kg. Unit concentration of potassium and infants' hematocrit value, K + level, pH, and base excess were measured before and after transfusion. Compared with control infants, study infants had similar transfusion needs, but received blood from significantly fewer donors. The age of the blood received by study infants was significantly older and had a higher plasma K + level. However, the change in infants' serum K + levels before and after a transfusion was not significantly different in the two groups, and no adverse effects from transfusion of older blood were observed. We conclude that a protocol that allows use of an assigned unit of packed red blood cells preserved with citrate- phosphate-dextrose-adenine anticoagulant until its expiration date is safe, minimizes donor exposures, and meets the transfusion needs of low birth weight neonates. (J P EDIATR 1994;125:92-6)

The collection of platelets by apheresis procedures.

Collection of platelets by apheresis has been a major advance in transfusion medicine. It has allowed the supply of a therapeutically beneficial component to grow with medical needs. Donors find fulfillment in more frequent donations than are possible with whole blood and know that their donation fills a special need. New technology allows leukocyte reduction in the collection of the component with or without the use of filtration. Matching for refractory patients is possible. However, platelets collected by apheresis have not been shown to be hemostatically different from platelets separated from whole blood donations, and thus, do not represent an advance in therapeutic efficacy. The use of apheresis platelets does reduce donor exposure, but this has not been shown to be a safety advance, although it seems intuitively obvious that transfusion risk is statistically reduced in some patients requiring only a few platelet transfusions. Support of patients by apheresis platelets may or may not reduce the risk of alloimmunization. Apheresis platelets from some equipment have less white blood cell contamination even in the absence of filtration, which may be an advantage. Apheresis platelets could be a major step in the ultimate customization of blood collection, in which some donors would preferentially donate red blood cells, whereas others would donate platelets or plasma depending on their blood type and ability to donate frequently, and the current medical need of their donation. Perhaps this would be the most significant advance from the medical progress initiated by Cohn almost 50 years ago.

Effective use of a strategy using assigned red cell units to limit donor exposure for neonatal patients

Critically ill neonatal infants receive frequent small-volume red cell (RBC) transfusions for replacement of blood drawn for laboratory analysis or for treatment of symptomatic anemia secondary to underlying medical conditions and/or a relative bleeding diathesis. Retrospective review of transfusion practice in a hospital revealed that the donor exposure-to-transfusion ratio was 1:1.3. In an effort to limit donor exposure and decrease the risk of transfusion-transmitted disease, a sterile connection device was used for multiple small-aliquot preparations. Three neonatal infants were given part of the same RBC unit, and the assigned RBC unit was used only until it reached 14 days of age. These criteria resulted in 49-percent reduction in donor exposure for neonatal infants weighting less than 1500 g and 27-percent reduction for those weighing more than 1500 g. The donor exposure-to-transfusion ratio decreased to 1:2.5. RBC waste from syringe aliquot preparation and residual volume at Day 15 were a mean of 32 percent of the total unit volume. Of 722 transfusion occurrences, there were no reported adverse effects due to elevated potassium subsequent to transfusion of 14-day-old RBCs. This limited-donor-exposure strategy effectively meets the needs of a transfusion service and will reduce the donor exposures of neonatal infants in similar institutions.

National Survey of Neonatal Transfusion Practices: I. Red Blood Cell Therapy

Neonatal blood component transfusion practices during 1989 were surveyed via a questionnaire developed by the Pediatric Hemotherapy Committee of the American Association of Blood Banks. Of 1790 questionnaires mailed, 452 were selected to form the database for this analysis because they were from institutions in which neonates were transfused. Nearly all institutions contained intensive care units directed by neonatologists and were involved in the management of high-risk infants. Results from institutions serving as the primary pediatric teaching hospital of a medical school were compared with those with no medical school affiliation. Thirty-six percent of primary pediatric teaching hospitals and 52% of hospitals with no medical school affiliation performed pretransfusion testing in excess of that required, resulting in additional blood loss in neonates. Sixty-six percent of primary pediatric teaching hospitals used fresh frozen plasma to adjust the hematocrit of red blood cell concentrates prior to transfusion (a practice increasing donor exposure), compared with only 29% of hospitals with no medical school affiliation. The usual indication for small-volume red blood cell transfusions in severely ill neonates was to maintain a desired hematocrit level, whereas for stable infants, red blood cell transfusions were given to treat symptomatic anemia, rather than to maintain a predetermined hematocrit. As found in 1985, neonatal transfusion practices in 1989 were variable. However, improvements have occurred since 1985 to suggest that further research and educational efforts may serve to promote even better neonatal transfusion therapy.

Special Issues in Transfusion Medicine

This article reviews four controversial aspects of transfusion practices: the clinical circumstances, survival, and complications of massive transfusion; specific problems related to neonatal transfusion practices and the surgical support of the small child, including the appropriate age for red cells to be transfused, cytomegalovirus transmission, and the reduction in homologous donor exposures; the clinical presentation, incidence, and prevention of transfusion-associated graft-versus-host disease; and the biochemistry, function, genetics, and clinical indication for replacement therapy of antithrombin III.

Safety and efficacy of autologous blood donation before elective aortic valve operation

Although the use of preoperative autologous blood donations for patients undergoing elective cardiac operations has increased dramatically in recent years, patients awaiting elective aortic valve replacement have traditionally been denied access to preoperative autologous blood collection programs. We report our experience with 79 patients, each of whom donated 1 to 3 units of autologous blood before an aortic valve operation. All patients had serious aortic valve disease as evidenced by symptoms and preoperative catheterization data. The patients collectively made 129 blood donations. One patient had a syncopal episode within 2 hours of donation and recovered without difficulty. Of the patients who gave autologous blood preoperatively, 68% avoided any homologous blood donor exposure during their subsequent hospitalization for aortic valve replacement. In contrast, in a group of 298 patients who did not give autologous blood preoperatively, only 31% avoided homologous blood exposure during aortic valve replacement ( p < 0.0001). Our experience suggests that preoperative autologous blood donation by patients awaiting elective aortic valve replacement is both safe and effective. Patients with aortic valve disease should not be routinely excluded from preoperative blood services.

HIV infection of multiply-transfused pediatric oncology patients in a low-prevalence area.

We attempted to determine the occurrence of transfusion-acquired HIV-1 infection in multiply-transfused pediatric oncology patients receiving blood products prior to donor HIV antibody screening in March 1985. We identified 85 multiply-transfused pediatric oncology patients (initially HIV-1 antibody negative) who had received 4,346 transfusions (968 red blood cells, 3,192 platelets, 137 fresh frozen plasma, and 49 leukocytes). Only one (1.2%) of these multiply-transfused pediatric oncology patients seroconverted following transfusion. Transfusion-acquired HIV-1 infection in our multiply-transfused pediatric oncology patients was infrequent despite marked exposure to blood products (average 51.2 donor exposures per multiply transfused pediatric oncology patients) and occurred at a frequency consistent with the prevalence of HIV-1 infection in our donor population (Central Ohio--2 of 10,000 donors were HIV-1 antibody positive). While our findings may not be unexpected, they offer documentation of a lower risk for transfusion-acquired HIV infection in our blood recipients than in some previous studies conducted in areas where donor HIV antibody prevalence is higher. We also document that the efforts associated with performing "Lookback" evaluations (contacting recipients of blood products from donors subsequently identified as HIV antibody positive) are valuable since our only HIV-1-infected, multiply-transfused pediatric oncology patient was identified in this manner.

Sepsis After Platelet Transfusions

To the Editor. —I read with interest the painstaking and well-executed study of Morrow et al 1 on transfusion-associated sepsis (TAS) after platelet transfusion. transfusion-associated sepsis occurred in seven of 29 738 transfusions, of which 10219 were platelet pools from multiple donors (MD) and 19519 were single donors (SD) obtained by apheresis. However, since the 10219 MD transfusions averaged 7.3 U of platelet concentrates per transfusion, a more pertinent denominator is the sum of all donor exposures, not transfusions. Thus, TAS occurred in seven of 94118 [(10219 × 7.3) + 19519] donor exposures, a rate of 0.0074%, or about one per 13460 exposures. This risk is some 30 to 40 times less than that of TA hepatitis and about five to 10 times greater than that of TA human immunodeficiency virus (HIV). 2 When the data in Morrow et al's Table 1 is recalculated (Table) using donor exposures as the

Decreasing transfusion exposure risk during extracorporeal membrane oxygenation (ECMO).

Extracorporeal membrane oxygenation (ECMO) is a lifesaving therapy for neonatal pulmonary hypertension but carries a significant risk for transfusion-related complications. Packed red blood cell (PRBC) and platelet exposure were quantified and reviewed in 17 ECMO survivors prior (Group I, n = 9) and subsequent to (Group II, n = 8) changes in transfusion protocols. Blood product requirements included ECMO circuit priming, maintenance of haematocrit > 0.40 or platelet count > 50 x 10(9)/l, and colloid volume expansion. Group I was exposed to 13.8 +/- 10.2 (x +/- SD) different PRBC units. In Group II, multiple transfusions from single donor units decreased exposure 71% to 3.9 +/- 0.7 units (P < 0.05). Decreases in blood withdrawn (11%) and transfusion volume (7%) were coincident with a 15% reduction in mean bypass time. Platelet volume transfusion decreased from 159 +/- 213 to 93 +/- 64 ml using volume-reduced platelet packs. Total transfusion exposure decreased 59% from 20.8 +/- 17.8 units to 8.6 +/- 2.4 donor units. No transfusion complications occurred during the aggregate 1,926 h on bypass. We conclude that neonates on ECMO have a significant transfusion exposure risk increasing with prolonged duration of ECMO therapy. In addition we noted that concentrated platelet packs decreased transfusion volume by 41%, and multiple PRBC transfusions from single donor units decreased donor exposure by 71% while both strategies decreased the overall transfusion exposure risk by 59%.

Less intensive long-term transfusion therapy for sickle cell anemia and cerebrovascular accident

To determine the efficacy of a less intensive transfusion regimen in preventing recurrent cerebrovascular accidents and reducing transfusion requirements in patients with sickle cell anemia, we offered to 14 patients who had been undergoing aggressive transfusion therapy (sickle hemoglobin concentration kept less than 30% of total) for a mean of 9 years the option of either diminishing or stopping transfusion therapy. Thirteen patients chose to continue a modified transfusion regimen to maintain sickle hemoglobin concentration less than 60%; 10 of these patients have now been followed for 1 year or more (12 to 27 months, mean 15.5 months). There have been no recurrent neurologic events, although two patients have died of complications of hemochromatosis. All patients had a reduction in donor exposure, and there was a mean reduction in net transfusion requirement of 31.4% during the first year after modification. The greatest reduction was achieved in the single patient managed by small-volume (5 ml/kg) simple transfusion rather than partial packed cell exchange. We conclude that although long-term consequences of less aggressive transfusion therapy are unknown, the use of such a regimen may be reasonable, particularly in patients with significant transfusional hemochromatosis.

Donor reactions during DDAVP-stimulated plasmapheresis.

Donor exposure can be strikingly reduced for patients with classical hemophilia A and von Willebrand's disease when large volumes of potent cryoprecipitated AHF are prepared from donors following DDAVP (1-deamino-8-D-arginine vasopressin) stimulation and automated plasmapheresis--a procedure called "plasma exchange donation." Although this procedure has been reported to be relatively safe for donors, data are limited. Accordingly, we studied 20 donors during 48 procedures using DDAVP (0.3 micrograms/kg IV) followed by 2-3 L plasma collection. Replacement fluid for each initial plasma exchange donation was plasma protein fraction; autologous cryoprecipitate-poor plasma was used for subsequent procedures. Mild reactions, particularly facial flushing, were noted in all 48 procedures. No procedure was discontinued, but four were modified due to either an increased pulse rate (> or = 20/min from baseline) or a fall in systolic or diastolic blood pressure (> or = 20 mm Hg from baseline). No donor was deferred or withdrew from the program. Based on our modest experience, DDAVP stimulated plasma exchange donation appears to be a safe and effective method for collecting large quantities of plasma from which potent cryoprecipitated AHF can be prepared.

The neonatal immune response to washed and irradiated red cells: lack of evidence of lymphocyte activation

A total of 21 neonatal infants (11 males and 10 females) were evaluated for lymphocyte subpopulation changes and cellular activation following the receipt of washed and gamma-irradiated red cells. The mean donor exposure was 2 +/- 1.5 donors, and the mean white cell concentration of each 10-mL-per-kg transfusion was 2 x 10(7) cells. A total of 2800 rad (28 Gy) was delivered to each red cell unit prior to washing. The lymphocyte subsets CD3+, CD4+, CD8+, CD19+, CD3+/CD25+, CD3+/HLA-DR, CD4+/CD45RA, CD4+/CDw29, and CD4+/ICHL-1 were analyzed, as were plasma gamma-interferon and neopterin levels, before and after blood transfusion. Posttransfusion samples were obtained from 3 to 12 days after the last blood transfusion. There were no posttransfusion changes in the percentage of lymphocyte subsets analyzed. Furthermore, overlay-histogram analysis of pretransfusion and posttransfusion CD45RA-, CDw29-, and UCHL-1-positive helper T cells failed to reveal a shift in mean channel fluorescence intensity, which is indicative of a lack of cellular activation. Gamma-interferon levels remained unchanged after transfusion (range, 90 +/- 5.9 to 95.5 +/- 5.3 pg/mL), as did neopterin levels (range, 3.7 +/- 1.5 to 4.6 +/- 1.5 ng/mL). This study could not find any evidence, by either cellular or humoral markers, of the activation of neonatal lymphocytes by transfusion. It is hypothesized that this failure to observe lymphocyte activation is due to the low number of donor white cells present in washed, irradiated red cells and/or to a lack of recipient recognition of transfused, allogeneic, donor white cells.

Is Blood Conservation Optimally Utilized?

Blood conservation and the subsequent prevention of transfusion have assumed an increasingly important role in cardiac surgery. The concern is one of preventing transmission of transfusion related diseases and of conserving an extremely valuable resource (1,2). Cardiac surgery with cardiopulmonary bypass has become the most common operation performed, thus attracting much analysis of transfusion practices. It is estimated that of the approximately 250,000 cardiopulmonary bypass procedures done in the United States each year, the majority require transfusion of blood products (3). It has been calculated that the cardiac surgery services throughout the United States use somewhat over 10% of all the blood product resources that are transfused in this country (4,5). Many methods of blood conservation have been described (Table 1), but there still exists a wide variance in blood product utilization for adult patients undergoing cardiopulmonary bypass procedures. A review of the literature reveals average packed red blood cell transfusion rates from 0.3 up to 8 units per patient (4,6-8). If we further add the transfusion of platelets, fresh frozen plasma, and cryoprecipitate, the total donor exposure to the patient goes up substantially more. A varied patient population has been cited as the reason for these discrepancies but it has been demonstrated in similarly matched groups of patients receiving transfusions, that the patterns were based to some extent upon "prevailing practice" rather than on need (9,10). The purpose of this study was to identify which methods of blood conservation were being practiced in a major metropolitan area within the United States where the risk of transfusion related disease is relatively high. Secondly, to stratify the frequency of use of particular blood conservation methods in order to estimate how often a particular method was utilized and by what percentage of respondents. Finally, to increase the awareness of the options and difficulties associated with current modalities of transfusion practice and blood conservation.

Limiting the Usage of Blood Products in Cardiovascular Surgery

We studied the effect of the initiation of a five part program of blood component conservation on blood product utilization in patients undergoing major cardiovascular surgery. We encouraged physicians and nurses to adhere to a set of guidelines that would limit the exposure of these patients to complications associated with blood product administration. Through this effort the amounts of packed red cells, fresh frozen plasma, platelets, and cryoprecipitate used were markedly reduced. After the start of the conservation program, overall blood product usage was reduced 29% despite a 46% increase in the surgical caseload, and there was a 53% decrease in the amount of donor exposure (units of individual blood products administered) per patient.

Minimal‐exposure transfusion and the committed donor

Autologous blood (collected preoperatively or salvaged intraoperatively) is the safest blood available for transfusion, but its use is not always feasible. It may be possible to decrease a patient's exposure to homologous donors. Pediatric cardiac surgery patients frequently are unable to donate autologous blood preoperatively. Since 1984, attempts have been made to provide parental apheresis platelets and intraoperative blood salvage to such patients to decrease their donor exposure. Further decreases in donor exposure have been the object of a program of collecting from one committed donor all the blood a patient is anticipated to need. This article reviews the experience with 50 pediatric cardiac surgery patients on such a program, in whom the mean decrease in homologous-donor exposure was 57 percent (range, 12-93%). Thirteen of these patients received only homologous blood products from one committed donor, for a mean decrease in homologous-donor exposure of 80 percent (range, 50-93%). A comparison of 12 of these 13 recipients with a matched control group showed no significant difference in red cell transfusion practice but a significant difference in the number of homologous-donor exposures per m2 of body surface area (BSA) (mean donor exposures/m2 of BSA: patients = 1.5, controls = 10.5). The use of one committed donor and autologous blood can provide a minimal-exposure transfusion.

Variability in the Fibrinogen and Von Willebrand Factor Content of Cryoprecipitate: Implications for Reducing Donor Exposure

Advances in the preparation of commercial Factor VIII concentrates have decreased the clinical use of cryoprecipitate to replace Factor VIII coagulant activity. Cryoprecipitate is now frequently transfused as a source of fibrinogen or von Willebrand factor (vWF). The minimum acceptable content of Factor VIII is prescribed, but no attempt is made to optimize, standardize, or assess the content of fibrinogen or vWF in cryo. If reasonably accurate information on the composition of cryoprecipitate were available, the physician could calculate an appropriate dose of cryo, thus avoiding unnecessary donor exposures and waste of product. This study was designed to measure the functionally active vWF and fibrinogen in cryoprecipitate prepared by three techniques in an attempt to optimize the yield of these hemostatically important components, and to obtain accurate information on the composition of the product. Cryoprecipitate was made from 82 units of fresh frozen plasma (FFP) as follows: (1) most of the supernatant plasma was expressed from "dry" cryo; (2) about 15 mL of plasma was left in each "regular" unit; and (3) "overnight" units were made from FFP thawed overnight in a refrigerator rather than in a 4 degrees C water bath as for the dry and regular units. Dry, regular, and overnight units had volumes of 8.8 +/- 1.5, 16.6 +/- 3.9, and 15.1 +/- 2.4 mL/bag, respectively. Dry cryoprecipitate units had significantly less fibrinogen and vWF than regular or overnight units. The vWF multimer pattern for all three types of cryoprecipitate was indistinguishable from that of normal pooled plasma. Thus, the amount of plasma expressed during preparation has a significant impact on the vWF and fibrinogen content of the resulting product. The amounts of these clinically important proteins should be assayed as a step toward rational determination of optimal cryoprecipitate doses in specific clinical settings.

Blood component therapy during the neonatal period: a national survey of red cell transfusion practice, 1985

A questionnaire to determine patterns of neonatal red cell transfusion practice during 1985 was mailed to 2200 blood banks of American Association of Blood Banks (AABB) institutional members and children's hospitals. There were 915 responses (41.6%); 785 responses (86%) contained sufficient data for analysis. The majority (70.6%) of 785 responding hospitals were community/urban institutions. However, more highly specialized, pediatric hospitals were also represented by 92 university/tertiary-care hospitals (11.7% of respondents) and 29 children's hospitals (3.7% of respondents). Two-thirds of hospitals performed a major antiglobulin crossmatch (rather than an abbreviated one) before all neonatal red cell transfusions. The red cell preparation most frequently selected for small-volume transfusions was ABO and Rh group-specific red cell concentrates. When performing only large-volume exchange transfusions, 19.2 percent of hospitals used whole blood; all others prepared reconstituted units of red cells plus fresh-frozen plasma, a practice that frequently causes exposure to two donors per unit. Another practice likely leading to multiple donor exposure is the use of fresh-frozen plasma to adjust the hematocrit of red cell preparations to a predetermined value prior to a small-volume transfusion. Over one-half of hospitals adjusting hematocrits used plasma, presumably from one donor, to dilute packed red cells from another donor, a practice that has no apparent medical benefit. Most hospitals (63.4%) provided red cells with a reduced risk of transmitting cytomegalovirus; blood from seronegative donors was selected by 65 percent of hospitals. The majority of hospitals, including most of the community/urban hospitals, did not irradiate blood products before transfusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Decreasing blood donor exposure in neonates on extracorporeal membrane oxygenation

Extracorporeal membrane oxygenation (ECMO) has been successful treatment (80% survival) in over 2,000 neonates with severe respiratory failure (80% predicted mortality without ECMO). Neonates on ECMO require frequent blood product replacement, which increases donor exposure (DE) and the risk of transfusion related complications. Successful, widespread usage of ECMO in neonatal respiratory failure is placing increased numbers of surviving infants at risk for acute and long-term transfusion related problems. We assessed DE rates in 21 consecutive neonatal ECMO survivors. In the first 12 patients packed red blood cell (PRBC) transfusions were administered as 10 mL/kg body weight for hematocrit less than 45%. PRBC exchange transfusions were used in patients with hematocrit less than 45% and hypervolemia. Fresh frozen plasma (FFP) and cryoprecipitate (CRYO) infusions were used empirically for evidence of hemorrhage. DE rates (donors per ECMO day, mean +/- SD) were: PRBC (2.8 +/- 0.6), FFP/CRYO (0.5 +/- 0.7), and platelet (2.0 +/- 1.0), with a total donor exposure rate of 5.3 +/- 2.0 donors per ECMO day. Mean duration of ECMO was 4.6 +/- 2.0 days and total DE per infant was 22.8 +/- 9.5 donors per ECMO run. In a protocol (n = 9) to minimize DE risks, exchange transfusions were eliminated and PRBC transfusion volumes were increased to 15 mL/kg. Empiric use of FFP and CRYO was discontinued. The blood bank divided standard units of PRBCs into four aliquots and dispensed each aliquot sequentially before dispensing blood from another unit.(ABSTRACT TRUNCATED AT 250 WORDS)