Assessing the performance of a plateletpheresis unit at a tertiary-care academic medical center in Mexico: A 6-year experience.

BACKGROUND: Optimization of platelet (PLT) apheresis collection is a priority to satisfy the increasing demand of hemato-oncology patients. We assessed the performance of a plateletpheresis unit supporting hematology patients. STUDY DESIGN AND METHODS: This descriptive retrospective study included 561 plateletpheresis collections from 2013 to 2018. For data analysis, descriptive statistics and receiver operating characteristic (ROC) curve were used. A 5-item satisfaction questionnaire was analyzed. RESULTS: Ninety percent of the donors were males. The median plateletpheresis time was 89 minutes; its success rate was 92.5%; median donor PLT count was 232 × 109 /L, women median PLT count was 247 × 109 /L vs 231x109 /L in men (P = .017). Seventy-seven percent donors were candidates for a double product and 24.5% were processed; 20.8% of these donors had a weight ≤75 and 79.2% >75 kg, P = .003, and 6.6% were women and 93.4% men, P = .161. Thirty-six of donors had ≥250 × 109 /L and 16.8% was processed as a triple product. ROC analysis showed that with donor PLT counts ≥200 × 109 /L the sensitivity for obtaining double products was 0.981 and specificity 0.714, with an area under the curve (AUC) = 0.877. The adverse effect rate was 4.3%. Of the potential donors, 6.3% were rejected. The cost of processing single or double products was 430 USD. Comfort and time spent during plateletpheresis were areas for improvement. CONCLUSION: Platelet count and donor weight predicted PLT yield and obtaining double products. Women had higher PLT counts, but no significant difference was found between donor gender and processed products. Assessment of the apheresis unit can help to improve its performance.

Effects of Intercept pathogen reduction treatment on extended cold storage of apheresis platelets.

BACKGROUND: Platelets pose the greatest transfusion-transmitted infectious risk among blood products. Refrigeration of platelets can mitigate bacterial contamination and extend platelet shelf life. Implementation of pathogen reduction technologies (PRTs) at blood banks has become increasingly popular to protect against emerging and reemerging infectious diseases. In this study, we sought to evaluate the effects of Intercept PRT on platelets collected on different platforms and cold-stored for up to 21 days in plasma and platelet additive solution (PAS). METHODS: Double-dose apheresis platelets were collected with use of a Trima or Amicus system into either 100% plasma or 65% InterSol PAS/35% plasma and split equally between two bags. One bag served as control, while the other received Intercept PRT treatment. Bags were stored unagitated in the cold and evaluated on Days 1, 7, 14, and 21 to assess platelet metabolism, activation, aggregation, and clot formation and retraction. RESULTS: By Day 14 of storage, lactate levels reached approximately 13 mmol/L for all samples irrespective of Intercept treatment. Mean clot firmness dropped from the 62.2- to 67.5-mm range (Day 1) to the 28.4- to 51.3-mm range (Day 21), with no differences observed between groups. Clot weights of Intercept-treated Trima/plasma samples were significantly higher than control by Day 14 of storage (P = .004), indicating a reduced clot retraction function. Intercept treatment caused a higher incidence of plasma membrane breakdown in plasma-stored platelets (P = .0013; Trima/plasma Day 14 Control vs Intercept). CONCLUSIONS: Intercept treatment of platelets and subsequent cold storage, in plasma or PAS, results in comparable platelet metabolism platelets for up to 14 days of storage but altered clotting dynamics. Pathogen-reduced platelets with an extended shelf life would be beneficial for the deployed setting and would greatly impact transfusion practice among civilian transfusion centers.

Changes in Hematological Indices and Lymphocyte Subsets in Response to Platelet Apheresis Donation.

BACKGROUND: Platelet apheresis is a technique in which whole blood is collected from a donor followed by platelet (PLT) separation. Platelet apheresis has a significant impact on some biochemical indices after donation. This study aimed to investigate the impact of platelet apheresis on complete blood count (CBC) and lymphocyte subsets over a typical interdonation interval. METHODS: Healthy male subjects (n = 10) were recruited to study changes in CBC and lymphocyte subsets before and at three intervals following platelet apheresis. Repeated measures ANOVA was used to compare quantitative variables between different visits. RESULTS: Following platelet apheresis, platelet count decreased 30% at 24 hours after donation (p < 0.001) compared to the baseline count with significant repeated ANOVA across different visits (p < 0.001, Eta = 0.558). No changes were observed in other variables of CBC. The lymphocyte subsets including CD4, CD8, and CD4/CD8 ratio were decreased at 24 hours after donation (-0.6%, -0.4% and -0.7%, respectively) but none was significant. At 24 hours, the proportion of CD19 and CD16-56 were slightly increased (1.6%, 3.3%, p > 0.05, respectively). CONCLUSIONS: The significant reduction in PLT count after 24 hours of plateletpheresis may have adverse health effects on PLT donors. Platelet apheresis has no significant effect on lymphocyte subsets of the donor.

Severe CD4+ T-cell lymphopenia is not observed in frequent plateletpheresis donors collected on the Fenwal Amicus.

BACKGROUND: In a recent study, we determined that 30% of frequent plateletpheresis donors collected using the Trima Accel Automated Blood Collection System (Terumo BCT) had a CD4+ T-cell count below 200 cells/µL. Whether CD4+ T-cell lymphopenia is associated with donation using other plateletpheresis instruments is unknown. STUDY DESIGN AND METHODS: We obtained blood samples from 30 current frequent Fenwal Amicus plateletpheresis donors. All participants had made 20 to 24 plateletpheresis donations in the most recent 365-day period, and all had previously donated over 50 times on the Fenwal Amicus instrument. Blood samples were analyzed to determine blood counts, including CD4+ and CD8+ counts. RESULTS: Of 30 study participants, none had a CD4+ count below 200 cells/µL. There was one participant with a CD4+ count between 200 and 300 cells/µL. This individual was over the age of 55 and had a history of more than 300 lifetime plateletpheresis sessions. One participant had a CD8+ count below the lower limit of normal (125 cells/µL) and a normal CD4+ count. CONCLUSION: We did not detect severe CD4+ lymphopenia in frequent platelet donors undergoing plateletpheresis with the Fenwal Amicus. Since the Fenwal Amicus does not incorporate a leukoreduction system chamber, this finding supports the hypothesis that such chambers-found in the Trima Accel instrument-contribute to CD4+ lymphopenia in frequent platelet donors.

Optimizing donor scheduling before recruitment: An effective approach to increasing apheresis platelet collections.

BACKGROUND/AIMS: Typical approach for increasing apheresis platelet collections is to recruit new donors. Here, we investigated the effectiveness of an alternative strategy: optimizing donor scheduling, prior to recruitment, at a hospital-based blood donor center. METHODS: Analysis of collections, during the 89 consecutive months since opening of donor center, was performed. Linear regression and segmented time-series analyses were performed to calculate growth rates of collections and to test for statistical differences, respectively. RESULTS: Pre-intervention donor scheduling capacity was 39/month. In the absence of active donor recruitment, during the first 29 months, the number of collections rose gradually to 24/month (growth-rate of 0.70/month). However, between month-30 and -55, collections exhibited a plateau at 25.6 ± 3.0 (growth-rate of -0.09/month) (p<0.0001). This plateau-phase coincided with donor schedule approaching saturation (65.6 ± 7.6% schedule booked). Scheduling capacity was increased by following two interventions: adding an apheresis instrument (month-56) and adding two more collection days/week (month-72). Consequently, the scheduling capacity increased to 130/month. Post-interventions, apheresis platelet collections between month-56 and -81 exhibited a spontaneous renewed growth at a rate of 0.62/month (p<0.0001), in absence of active donor recruitment. Active donor recruitment in month-82 and -86, when the donor schedule had been optimized to accommodate further growth, resulted in a dramatic but transient surge in collections. CONCLUSION: Apheresis platelet collections plateau at nearly 2/3rd of the scheduling capacity. Optimizing the scheduling capacity prior to active donor recruitment is an effective strategy to increase platelet collections at a hospital-based donor center.

Plateletpheresis efficiency and mathematical correction of software-derived platelet yield prediction: A linear regression and ROC modeling approach.

BACKGROUND: Advances in automated cell separators have improved the efficiency of plateletpheresis and the possibility of obtaining double products (DP). We assessed cell processor accuracy of predicted platelet (PLT) yields with the goal of a better prediction of DP collections. STUDY DESIGN AND METHODS: This retrospective proof-of-concept study included 302 plateletpheresis procedures performed on a Trima Accel v6.0 at the apheresis unit of a hematology department. Donor variables, software predicted yield and actual PLT yield were statistically evaluated. Software prediction was optimized by linear regression analysis and its optimal cut-off to obtain a DP assessed by receiver operating characteristic curve (ROC) modeling. RESULTS: Three hundred and two plateletpheresis procedures were performed; in 271 (89.7%) occasions, donors were men and in 31 (10.3%) women. Pre-donation PLT count had the best direct correlation with actual PLT yield (r = 0.486. P < .001). Means of software machine-derived values differed significantly from actual PLT yield, 4.72 × 1011 vs.6.12 × 1011 , respectively, (P < .001). The following equation was developed to adjust these values: actual PLT yield= 0.221 + (1.254 × theoretical platelet yield). ROC curve model showed an optimal apheresis device software prediction cut-off of 4.65 × 1011 to obtain a DP, with a sensitivity of 82.2%, specificity of 93.3%, and an area under the curve (AUC) of 0.909. CONCLUSION: Trima Accel v6.0 software consistently underestimated PLT yields. Simple correction derived from linear regression analysis accurately corrected this underestimation and ROC analysis identified a precise cut-off to reliably predict a DP.

A simulation-based apheresis platelet inventory management model.

BACKGROUND: The primary goals of apheresis platelet (AP) inventory management are to meet demand and minimize waste. AP inventory management is complicated by unpredictable demand for a product with a shelf life of only a few days and by hospital requests for APs that match the ABO types of patients identically. STUDY DESIGN AND METHODS: A simulation-based decision support system was developed to assist blood centers in reducing waste while meeting the demand for ABO-identical APs. The proposed model is validated using data from a blood center located in a major city in the southeast region of the United States. RESULTS: Based on data provided by the blood center, the proposed simulation model is able to suggest appropriate collection strategies that can reduce AP waste from 12%-14% to 6%-7% and decrease the unmet demand for ABO-identical APs from 25% to 21%. CONCLUSION: The proposed simulation-based decision-making model is able to mimic the complexity of the AP inventory management system while reducing waste and predicting the need for ABO-identical APs.

Reducing the financial impact of pathogen inactivation technology for platelet components: our experience.

BACKGROUND: Pathogen inactivation (PI) technology for blood components enhances blood safety by inactivating viruses, bacteria, parasites, and white blood cells. Additionally, PI for platelet (PLT) components has the potential to extend PLT storage time from 5 to 7 days. STUDY DESIGN AND METHODS: A retrospective analysis was conducted into the percentage of outdated PLT components during the 3 years before and after the adoption of PLT PI technology in our institution. The PLT transfusion dose for both pre-PI and post-PI periods was similar. A retrospective analysis to study clinical safety and component utilization was also performed in the Balearic Islands University Hospital. RESULTS: As a result of PI implementation in our institution, the PLT production cost increased by 85.5%. However, due to the extension of PLT storage time, the percentage of outdated PLT units substantially decreased (-83.9%) and, consequently, the cost associated with outdated units (-69.8%). This decrease represented a 13.7% reduction of the initial cost increase which, together with the saving in blood transportation (0.1%), led to a saving of 13.8% over the initial cost. Therefore, the initial 85.5% increase in the cost of PLT production was markedly reduced to 71.7%. The mean number of PLT concentrates per patient was similar during both periods. CONCLUSIONS: The extension of PLT storage time can substantially contribute to reducing the financial impact of PI by decreasing the percentage of outdated PLTs while improving blood safety. Since the adoption of PI, there have been no documented cases of PLT transfusion-related sepsis in our region.

Evaluation of donor factors contributing to plateletpheresis yields among apheresis platelet donors.

BACKGROUND: The University of California, Irvine Blood Donor Center operates a plateletpheresis donor program utilizing the Amicus Cell Separator. Plateletpheresis donors may donate one or more apheresis platelet (PLT) units per collection event. This study seeks to characterize UC Irvine's donor pool by identifying biometric and demographic attributes predictive of double product (DP) collections. STUDY DESIGN AND METHODS: Biometric, demographic and procedural data from 1,786 apheresis donors were collected and entered into Excel spreadsheets. Of the 1,786 successful plateletpheresis procedures performed from January 2009 to April 2012, 1,442 of the donations were performed using double-needle (DN) kits. Only data from DN-kit collections were used for statistical analyses. The Classification And Regression Tree (CART) algorithm was used to help identify variables predictive of donating multiple PLT units in a single collection event. RESULTS: Donors weighing 75.7 kg or greater appear to be twice as likely to donate DPs as those weighing less than 75.7 kg. For donors weighing less than 75.7 kg, females appear to be twice as likely to donate DPs as males. Donors exhibiting platelet counts of 216.5 K/mcL or greater appear to be twice as likely to donate DPs as those with platelet counts fewer than 216.5 K/mcL. CONCLUSION: Weight, sex, and PLT count were identified as the most predictive donor attributes that separate UCI donors into DP donors and non-DP donors. Greater weights, greater PLT counts, and female sex confer to greater PLT yields per given amount of time.

The relationship of platelet yield, donor's characteristic and apheresis instruments in China.

Platelet yield was associated with donor's characteristic and property of apheresis instruments. Here, we have analyzed the relationship of platelet yield, physiologic parameters of donors for different apheresis instruments in China. Data were consecutively retrieved from plateletapheresis donors during March 1, 2007 and March 1, 2012. Three different apheresis instruments MCS+, Amicus, Trima system were used for plateletapheresis and defined as group 1, 2 and 3 respectively. Totally 77,091 Plateletapheresis donations were performed in this study. 17 donations were finally aborted because of vasovagal reaction with syncope. 5861, 37,036, 34,177 donations were performed in group 1, 2 and 3 respectively. Hct and platelet values before donations were similar, but platelet yield and collection rate were showed significantly difference (p<0.05) among the three groups. The values of platelet and Hct in the males before donations were higher than those in the females, and the platelet yield and collection rate were showed significantly difference between the male group and female group (p<0.05). The overall reaction rate was 1.56%. Most donors were chosen the group 2 (51.6%) for next donation, followed by group 3 (33%) and group 1 (15.4%). We concluded that the platelet yield and collection rate in the male group were higher than those in the female group and the efficiency of plateletapheresis was associated with the kind of apheresis instruments and donor's characteristic. These data will help to work out suitable apheresis protocol based on the Chinese donor's characteristic.

Effects of prestorage vs poststorage leukoreduction on the rate of febrile nonhemolytic transfusion reactions to platelets.

The purpose of this study was to assess the incidence of febrile nonhemolytic transfusion reactions (FNHTRs) to concurrent transfusions of prestorage-leukoreduced (PreSLR) pooled platelets, poststorage-leukoreduced (PostSLR) pooled platelets, nonleukoreduced (NonLR) pooled platelets, and apheresis single-donor platelets (SDPs) to compare the rates of FNHTRs to PreSLR vs PostSLR pooled platelets. Reported transfusion reactions to platelets at 15 hospitals for a period of 45 months were retrospectively reviewed. Reaction rates to different types of platelet products were calculated and compared. During the study period, 70,015 platelet transfusions were administered. Among these, 152 (0.22%) FNHTRs and 111 (0.16%) allergic transfusion reactions were seen. Reported rates of FNHTRs were 0.07% (SDP), 0.16% (PreSLR), 0.30% (PostSLR), and 0.20% (NonLR) (P < .05 for PreSLR vs PostSLR). Rates of allergic reactions were 0.16% (SDP), 0.17% (PreSLR), 0.18% (PostSLR), and 0.11% (NonLR) (P > .05). The rates of reported FNHTRs were low for all types of platelet transfusions. SDPs and PreSLR pooled platelets were associated with a slightly lower rate of FNHTR compared with PostSLR pooled platelets.

[Contribution of platelet concentrates to oral and maxillo-facial surgery]. / Dérivés plaquettaires et chirurgie orale et maxillo-faciale.

INTRODUCTION: We evaluated the clinical contribution of platelet concentrates to oral and maxillo-facial surgery. MATERIAL AND METHOD: This bibliographic research was made using the PubMed MeSH database with the following keywords: "platelet rich fibrin" (PRF), "platelet rich plasma" (PRP), "bone", "facial bone", "dental implant", and "blood platelet". The research was made without any date or language limitation since English summaries were available. All summaries were read to evaluate the relevance of the article. Only original articles and case reports were considered. The articles were classified as "in vitro studies", "animal experiments", or "clinical studies". The research was stopped on March 22, 2012. RESULTS: One hundred and sixty-nine articles were validated after excluding irrelevant articles, reviews, technical notes, and articles without English or French summaries. Seventeen were in vitro studies, 61 animal experiments, and 91 clinical studies. One hundred and ten complete articles were read to complete summary data. The data of in vitro studies univocally supports of using platelet concentrates. The data from animal experiment studies was less consensual and the validity of animal models was contested. The disparity of clinical study designs and the lack of rigorous methodology did not allow clearly determining platelet concentrate benefits for oral and maxillo-facial surgery. DISCUSSION: PRF or PRP clinical benefit has not been clearly demonstrated yet. French regulations relative to their use should be clarified.

Events at blood collection area due to nonconforming blood bags and plateletpheresis kits: need for timely corrective and preventive actions.

BACKGROUND: Good blood banking practice requires that every effort should be made to detect any deviation or defect in blood bank products and to identify any potential risk to blood donor or recipient(s). We report the findings of an exercise that provide an insight into why feedback from the user side is crucial. STUDY DESIGN AND METHODS: Various events involving blood bags and plateletpheresis kits and the corresponding appropriate actions instituted for remedial measures were recorded. These scattered events were recorded for 6 months following the use of a new batch of improved blood bags with add-on features. Several events related to plateletpheresis kits from three different manufacturers were also recorded for 1 year. RESULTS: The affected blood bags were utilized with no untoward incident. The complaint was closed following satisfactory response from the blood bag manufacturing company that acted in a timely manner in addressing the root causes of the problems. However, corrective and preventive actions (CAPA) could not be implemented for plateletpheresis kits. The rate of undesirable events was higher with plateletpheresis kits as compared with whole blood bags (1.75% vs. 0.06%). CONCLUSION: As defects or deviations that trigger the need for CAPA can stem from numerous sources, it is important to clearly identify and document the problems and level of risk so that appropriate investigations can be instituted and remedial actions can be taken in a timely manner. This study demonstrates the usefulness of a quality initiative to collate and analyze blood product faults in conjunction with blood product manufacturers.

Demographics of apheresis platelet donors in five blood centers in China.

BACKGROUND: Blood component donations by apheresis has become more common in modern blood transfusion practices. However, apheresis donation still remains less common in China. This study describes the demographic profile and transfusion-transmissible infection (TTI) prevalence among donors making apheresis platelet (AP) donations compared to those making whole blood (WB) donations and the differences among five geographically diverse blood centers in China. STUDY DESIGN AND METHODS: This is a descriptive study using data from all successful donations at the five blood centers in 2008 and 2009. Donor demographic and TTI screening reactive rates were collected for WB and AP donations and blood centers. Logistic regression was used to identify independent factors associated with AP donations. RESULTS: From January 1, 2008, to December 31, 2009, there were 512,594 WB and 26,199 AP donations at five blood centers. AP donations accounted for 4.9% of all donations. AP donations have lower reactive rate than WB donations for hepatitis B virus surface antigen, hepatitis C virus antibodies, human immunodeficiency virus antibodies, and syphilis screening testing. Males, donors older than 25 years old, non-Han donors, and donors with below high school educational level were more likely to make AP donations. The characteristics of AP donations differed among the five Chinese blood centers. CONCLUSION: Our analysis suggests that the characteristics of AP donations in China are different from WB donations and differ among the five Chinese blood centers. Some of the differences are likely due to different recruitment policies. Further studies should be conducted to understand what motivates Chinese blood donors to participate as AP donors.

Transfusion-related acute lung injury prevention measures and their impact at Canadian Blood Services.

BACKGROUND: Blood operators have taken measures to reduce transfusion-related acute lung injury (TRALI). We classified suspected TRALI cases reported to Canadian Blood Services from 2001 to 2009 and assessed the impact of TRALI reduction measures. STUDY DESIGN AND METHODS: Using Canadian Consensus Conference definitions, cases were reviewed by two experts or, from 2006 to 2009, a TRALI Medical Review Group (TMRG). Detection of HLA antibodies was performed using the Luminex system starting in 2008. Measures implemented from 2007 to 2009 included use of predominantly male plasma, suspension of buffy coat platelets in male plasma, and deferral of females with a pregnancy history from plateletpheresis. The buffy coat production method was implemented from 2005 to 2008. RESULTS: Reporting of all suspected TRALI cases, as well as cases classified as definite or possible, increased from 2001 to 2004, was stable from 2004 to 2007, and declined in 2008 to 2009. The decline was most marked for plasma-associated cases, but occurred for all components. TMRG consensus on classification was achieved in 56% of cases. Cases identified as definitive or possible TRALI were significantly more likely to have donor antibody against a corresponding recipient antigen, compared to other cases. CONCLUSION: Hemovigilance data demonstrated an initial increase in TRALI cases, likely due to increased adverse event reporting and awareness of TRALI, followed by a decrease in cases related to all components. TRALI prevention measures and possibly the switch to the buffy coat production method may have contributed to the decline. Classification of cases remains challenging.

Blood donations from previously transfused or pregnant donors: a multicenter study to determine the frequency of alloexposure.

BACKGROUND: Transfusion-related acute lung injury (TRALI) mitigation strategies include the deferral of female donors from apheresis platelet (PLT) donations and the distribution of plasma for transfusion from male donors only. We studied the implications of these policies in terms of component loss at six blood centers in the United States. STUDY DESIGN AND METHODS: We collected data from allogeneic blood donors making whole blood and blood component donations during calendar years 2006 through 2008. We analyzed the distribution of donations in terms of the sex, transfusion and pregnancy histories, and blood type. RESULTS: A TRALI mitigation policy that would not allow plasma from female whole blood donors to be prepared into transfusable plasma components would result in nearly a 50% reduction in the units of whole blood available for plasma manufacturing and would decrease the number of type AB plasma units that could be made from whole blood donations by the same amount. Deferral of all female apheresis PLT donors, all female apheresis PLT donors with histories of prior pregnancies, or all female apheresis PLT donors with histories of prior pregnancies and positive screening test results for antibodies to human leukocyte antigens (HLAs) will result in a loss of 37.1, 22.5, and 5.4% of all apheresis PLT donations, respectively. CONCLUSION: A TRALI mitigation policy that only defers female apheresis PLT donors with previous pregnancies and HLAs would result in an approximately 5% decrease in the inventory of apheresis PLTs, but would eliminate a large proportion of components that are associated with TRALI.

Study of iron stores in regular plateletpheresis donors.

Plateletpheresis donors will lose up to 100 mL of blood at each donation, leading to concern that they may become iron deficient, particularly if donating at the maximum allowed frequency under National Blood Service policy of every 2 weeks. The serum ferritin levels of 508 regular plateletpheresis donors and 101 non-donors were measured to indicate the level of their iron stores. About 33.9% (156/460) of platelet donors had depleted iron stores compared with 3.1% (3/97) non-donors. Results for male and post-menopausal female donors were similar with 36.2% (131/362) of males and 37.7% (20/53) of post-menopausal females showing iron depletion. There was clear correlation with donation frequency in males with 63.9% (46/72) of males donating at 2 weekly intervals found to be iron depleted. The percentage of iron depleted male subjects decreased as donation intervals increased. Correlation with lifetime donations of platelets was not demonstrated, although no donor who had given fewer than 14 blood and/or platelet donations was found to be iron depleted. In males there was a clear correlation between iron depletion and frequency of donation. There appeared to be no correlation with lifetime number of platelet donations. As a result of this study, we have advised that volunteers should not donate platelets more than 15 times per year, so that red cell loss is no more than the equivalent of three whole blood donations (1500 mL).

The association of gender, age, body mass index, and vital signs in healthy plateletapheresis donors.

In order to determine the association between gender, age, body mass index and vital signs among healthy plateletapheresis donors, the mean and median values from the most recent donations of 236 plateletapheresis donors were calculated for age, body mass index (BMI), oral temperature, blood pressure (BP), and pulse. Values of these parameters were compared after stratification by gender, age, and BMI and multiple regression analysis between parameters performed. Gender, age, and BMI were associated with significant differences in vital signs of healthy plateletapheresis donors.

Acute plateletpheresis and aprotinin reduces the need for blood transfusion following Ross operation.

The effect of acute intraoperative plateletpheresis (25% platelet yield) in combination with intraoperative low-dose aprotinin (2 million units) on blood conservation was investigated in 18 young adult patients undergoing elective Ross operation. The results were compared with a group of 19 similar patients without plateletpheresis (control group). The hematological and coagulation parameters at admission and discharge were statistically similar in both groups. The total blood product transfusion requirements were significantly reduced in the plateletpheresis group compared with the control group (3.2 units and 5.1 units, respectively, P=0.036). The total blood donor exposure was also reduced significantly in the plateletpheresis group compared with the control group (3.2 and 6.9 donors/patient, respectively, P<0.001). The direct costs for the hospital for the plateletpheresis procedure, including costs for all blood products, were similar to those for blood products alone in the control group. In summary, acute plateletpheresis in combination with low-dose aprotinin significantly reduces the blood product transfusions and blood donor exposures following the Ross operation; the treatment is cost-effective.

Increase in platelet count is not affected by the platelet yield of single donor pheresed platelets.

OBJECTIVES: To determine if the rise in platelet count after transfusion in neonates is associated with platelet yield of the pheresed platelet unit. STUDY DESIGN: Cohort study of infants in a level 3 Neonatal Intensive Care Unit that received single donor platelets (SDP). Platelet rise in infants were compared between 3 groups: underproduction, destruction, and idiopathic. The main outcome variable studied was the rise in platelet count posttransfusion. Statistical analysis included analysis of variance, Pearson correlation, and multivariate linear regression. RESULTS: The gestational age was 28+/-4.5 weeks. The platelet yield was 4.2+/-0.7 (x10(11)) and resultant platelet rise was 71+/-58.6x1000/mm3. Infants with platelet underproduction (n=30) had a greater rise compared with infants with platelet destruction (n=51) after transfusion (95.3+/-58 vs. 59.6+/-57.5x1000/mm3, P=0.01). After controlling for confounding variables, there was no correlation between the platelet yield and platelet rise, but the etiology of the thrombocytopenia remained associated with increased platelet rise. CONCLUSIONS: There was no association between platelet yield of SDP and platelet rise. Infants with thrombocytopenia related to platelet underproduction had a greater rise in platelets after transfusion compared with those with platelet destruction, independent of yield or volume of the SDP transfusion.