Factors affecting platelet yield and their impact on the platelet increment of patients receiving single donor PLT transfusion

Platelet transfusions in adult ICU patients with thrombocytopenia: A sub-study of the PLOT-ICU inception cohort study

BACKGROUND

Platelet transfusions are frequently used in the intensive care unit (ICU), but current practices including used product types, volumes, doses and effects are unknown.

STUDY DESIGN AND METHODS

Sub-study of the inception cohort study 'Thrombocytopenia and Platelet Transfusions in the ICU (PLOT-ICU)', including acutely admitted, adult ICU patients with thrombocytopenia (platelet count <150 × 109/L). The primary outcome was the number of patients receiving platelet transfusion in ICU by product type. Secondary outcomes included platelet transfusion details, platelet increments, bleeding, other transfusions and mortality.

RESULTS

Amongst 504 patients with thrombocytopenia from 43 hospitals in 10 countries in Europe and the United States, 20.8% received 565 platelet transfusions; 61.0% received pooled products, 21.9% received apheresis products and 17.1% received both with a median of 2 (interquartile range 1-4) days from admission to first transfusion. The median volume per transfusion was 253 mL (180-308 mL) and pooled products accounted for 59.1% of transfusions, however, this varied across countries. Most centres (73.8%) used fixed dosing (medians ranging from 2.0 to 3.5 × 1011 platelets/transfusion) whilst some (mainly in France) used weight-based dosing (ranging from 0.5 to 0.7 × 1011 platelets per 10 kg body weight). The median platelet count increment for a single prophylactic platelet transfusion was 2 (-1 to 8) × 109/L. Outcomes of patients with thrombocytopenia who did and did not receive platelet transfusions varied.

CONCLUSIONS

Among acutely admitted, adult ICU patients with thrombocytopenia, 20.8% received platelet transfusions in ICU of whom most received pooled products, but considerable variation was observed in product type, volumes and doses across countries. Prophylactic platelet transfusions were associated with limited increases in platelet counts.

Effect of donor parameters and cell separators on yield of apheresis platelet and their impact on corrected count increment in aplastic anemia patients

BACKGROUND

The new cell separators make it simple to collect single donor platelets (SDP), although the platelet yield may vary depending on the cell separator used and donor-related clinical and laboratory variables.

AIMS

This study aims to study the factors affecting SDP yield and corrected count increment (CCI).

MATERIALS AND METHODS

This retrospective study was carried out at a tertiary care facility in northern India, over 4 years (May 2017-April 2020), data were retrieved and analyzed.

STATISTICAL ANALYSIS

Categorical variables were presented as proportions, while continuous variables were presented as mean with standard deviation, P < 0.05 was considered significant.

RESULTS

We found a positive correlation between predonation platelet count and yield (r = 0.243, P = 0.000). No such significant correlation was found with Hb concentration (r = 0.025, P = 0.720), age (r = 0.016, P = 0.820), sex (r = -0.038, P = 0.584), and weight (r = -0.025, P = 0.714). Maximum platelet yield and minimum time were seen with Trima. Only 39.3% (33/84) meet the 24 h CCI. The majority of patients did not meet the desired CCI could be due to the patients' clinical condition. On logistic regression, we found a significant association of 24 h CCI with product yield (odds ratio [OR] = 0.168, P = 0.015) and posttransfusion platelet count (OR = 0.454, P < 0.05).

CONCLUSION

The only donor-related factor that influences yield is predonation platelet count, whereas 24 h CCI may depend on the clinical status of the patient and yield.

Effect of double dose plateletpheresis on target yield and donor platelet recovery

INTRODUCTION

The demand for apheresis platelets has increased in the recent past and the shrinking donor pool has shifted the trend to collection of double-dose or higher yield of platelets.

OBJECTIVE

The present study aimed to determine the effect of double-dose plateletpheresis on the target yield and donor platelet recovery.

METHODS

The study was conducted on 100 healthy plateletpheresis donors, 50 of whom were in the study group, which underwent double-dose plateletpheresis (DDP), and 50 of whom were in the control group for single-donor plateletpheresis. Pre- and post-procedure samples of donors were subjected to a complete blood count. The DDP product was sampled for platelet yield and then split into two parts. Platelet yield, collection efficiency, collection rate, recruitment factor and donor platelet loss were calculated.

RESULTS

The mean platelet yield in the SDP was 4.09 ± 1.15 × 10¹¹ and in the DDP, 5.93 ± 1.04 × 10¹¹. There was a significant correlation between the pre-donation platelet count and platelet yield. The total of platelets processed for the SDP were 5.42 ± 1.08 × 10¹¹ and for the DDP, 7.94 ± 0.77 × 10¹¹. The collection efficiency was 71.93 ± 25.14% in the SDP and 72.94 ± 16.28% in the DDP, while the collection rates were 0.78 × 10¹¹ and 0.94 × 10¹¹ per minute, respectively. The average recruitment factor observed was 0.98 in the SDP, while it was 0.99 in the DDP. The mean platelet loss observed in the SDP was 35.55 ± 8.53% and in the DDP, 37.76 ± 8.65%.

CONCLUSION

The double-dose plateletpheresis supplements the platelet inventory in developing countries where the apheresis donor pool is limited. It is prudent to ensure stringent donor selection criteria for donors donating high-yield platelet products, thus enhancing donor safety and retention.

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.

A Study on Influence of Donor Hematocrit on the Procedural Parameters of Concentrated Single Donor Platelets Collected by Two Apheresis Devices

With improvements in apheresis collection, platelet additive solution (PAS) is steadily replacing plasma as the storage medium in single donor platelets (SDP). Concentrating platelets in SDP with one-third of plasma and two-thirds of PAS is referred as Concentrated-SDP (C-SDP). We studied the influence of donor hematocrit (Hct) in C-SDP procedures. A retrospective study, consisting of 124 and 95 plateletpheresis donors in MCS+ and Trima respectively. We compared two apheresis equipments MCS+ and Trima with regard to donor hematocrit on procedural parameters such as collection efficiency (CE), collection rate (CR), yield per hour (Y/H), yield per litre (Y/L) and percentage blood volume processed (%BV) during C-SDP procedures. Donors were categorized into two groups with Group A (Hct ≤ 46%) and Group B (Hct > 46%) based on mean baseline Hct of the study population. Among the 219 procedures, the overall CE was significantly higher for Trima over MCS+ equipment (77 vs 56, P < 0.001). However, there was no difference in procedural outcomes like CE, Y/L, Y/H, CR with MCS+ or Trima equipment between groups. %BV processed had a negative correlation with hematocrit in MCS+ (r = - 0.305, P = 0.001) and no difference was observed with Trima equipment. Donor Hct influences C-SDP collection only in processed blood volume with MCS+ equipment. Trima had statistically better performance over MCS+ equipments in all procedural parameters during C-SDP procedures. The data will guide apheresis centre to choose equipments based on donor characteristics.

Clinical and quality evaluation of apheresis vs random-donor platelet concentrates stored for 7 days

BACKGROUND AND OBJECTIVES

The clinical efficacy of different types of platelets remains under debate. We conducted a pilot study to prospectively evaluate the impact of subsequent storage on the in vitro quality and post-transfusion outcome of apheresis prepared platelets (APCs) vs random donor platelets (RDPs).

MATERIALS AND METHODS

We studied 30 units of APCs, and 30 units of RDPs. We performed assays on days 1, 3, 5 and 7, evaluating ADP aggregation, platelet count and pH. Fifteen thrombocytopenic patients with haematologic conditions were evaluated. Each patient received prophylactic transfusions of both components, and their post-transfusion platelet increments were compared. Twenty-five transfusions were apheresis prepared, and 35 transfusions were received as RDPs. None of the RDPs were leukoreduced.

RESULTS

The median platelet counts for APCs on days 1, 3, 5 and 7 were; 2070, 1990, 1680 and 1240 × 10(3)  µL(-1) , respectively, and were; 1290, 850, 499 and 284 × 10(3)  µL(-1) , respectively for RDPs. The pH of all units was more than 6·2. Both groups demonstrated a significant decrease of ADP aggregation after 3 days of storage (P < 0·05). However, APCs provided satisfactory increments for 90·9% of transfusions. On the sixth and seventh days of storage, APCs provided significantly higher platelet increments (18·7 × 10(3)  µL(-1) ) compared with RDPs (3·20 × 10(3)  µL(-1) ) (P < 0·05). Significantly longer transfusion intervals were also achieved with APCs (P < 0·05).

CONCLUSION

Although other variables may have confounded the results, subsequent storage of APCs appeared to provide higher increments with longer intervals of transfusion compared with RDPs. Future prospective studies are needed, adjusting for other possible confounding variables.

Minor diurnal and activity-induced variations in daytime peripheral blood platelet counts do not have any major impact on platelet yield by platelet apheresis

Physical activity alters systemic levels of several angioregulatory cytokines that affect microvascular endothelial cells and can be assumed to influence vascular permeability. This may alter platelet release to the bone marrow microcirculation and thereby the levels of circulating platelets. We investigated effects of physical activity on angioregulatory chemokines (CXCL8, 9, 10 and 11) and peripheral blood platelet counts before and after intensive physical activity in young adults, and also compared platelet yields obtained by platelet apheresis performed in the morning and in the afternoon in 20 healthy donors. Physical activity increased serum CXCL10 levels and platelet counts but did not alter the other chemokine concentrations. In the apheresis donors, there was only a minor increase in platelet counts during the day, and the platelet yields did not differ significantly between platelet concentrates collected early in the morning and late in the afternoon. In conclusion, minor intra-individual variations in platelet counts do not seem to have major influence on platelet yields by platelet apheresis.

Automated platelet collection using the latest apheresis devices in an Indian setting

In a developing nation like India where there is a scarcity of resources and voluntary donors, provision of safe and good quality blood and its components is a huge challenge. The demand for platelets is increasing constantly due to better management of various patient categories, specifically hemato-oncological cases, where there is an increased demand of platelet transfusion. The use of apheresis single donor platelets (SDPs) has been attributed to increased gap between demand and supply of whole blood derived random donor platelets (RDPs). Moreover, the other benefits of SDPs such as decreased donor exposure and simplification of inventory management cannot be overlooked. However, the increased costs and logistic problems, compounded by the lack of awareness, limit the donor recruitment and procedures for SDPs. In Indian scenario, there are no specific guidelines or standards available which can be followed, while simultaneously addressing the associated problems. In this review, we have tried to analyze the various problems of donor selection, donor safety and the quality issues regarding plateletpheresis. Based on this we have tried to give certain recommendations which might help the centers in resolving the problems related to plateletpheresis.

Efficacy and Adverse Events of Platelet Transfusion Product-Specific Differences

SUMMARY: TWO PREPARATIONS ARE AVAILABLE FOR PLATELET TRANSFUSION: single-donor apheresis platelet concentrates (APC) and pooled platelet concentrates (PPC) prepared from 4-6 whole blood units. Clear advantages of APC over PPC are a markedly reduced donor exposure of recipients, and easier logistics when attempting a complete supply with ABO-identical and Rh-compatible platelet concentrates. Regulations should aim at complete ABO-identical platelet transfusions because major and minor ABO-incompatible platelet transfusions are probably associated with significantly increased morbidity and mortality. The main advantage of PPC is lower costs. Preparation of PPC is however inevitably accompanied by substantial wastage of plasma and red cells. Only major supraregional blood transfusion centers can guarantee full-coverage supply with ABO-identical and Rh-compatible PPC. Whether APC are more effective than PPC and associated with fewer septic platelet transfusion reactions as shown in some but not all studies, has to be examined in future prospective controlled trials.