A randomized cross-over study of cryopreserved platelets in prophylactic transfusions of thrombocytopenic patients.

BACKGROUND: The short shelf-life of liquid-stored platelets (LP) at 20-24°C poses shortage and wastage challenges. Cryopreserved platelets have significantly extended shelf-life, and were safe and efficacious for therapeutic transfusions of bleeding patients in the Afghanistan conflict and phase 2 randomized studies. Although hematology patients account for half of platelets demand, there is no randomized study on prophylactic cryopreserved platelet transfusions in them. METHODS: We performed a phase 1b/2a randomized cross-over study comparing the safety and efficacy of cryopreserved buffy coat-derived pooled platelets (CP) to LP in the prophylactic transfusions of thrombocytopenic hematology patients. RESULTS: A total of 18 adults were randomly assigned 1:1 to CP and LP for their first thrombocytopenic period (TP) of up to 28-days. A total of 14 crossed over to the other platelet-arm for the second TP. Overall, 17 subjects received 51 CP and 15 received 52 LP. CP-arm had more treatment emergent adverse event (29.4% vs. 13.3% of subjects, 9.8% vs. 3.8% of transfusions) than LP-arm but all were mild. No thromboembolism was observed. Both arms had similar bleeding rates (23.5% vs. 26.7% of subjects) which were all mild. Subjects in CP-arm had lower average corrected count increments than LP-arm (mean [SD] 5.6 [4.20] vs. 22.6 [9.68] ×109 /L at 1-4 h, p < .001; 5.3 [4.84] vs. 18.2 [9.52] ×109 /L at 18-30 h, p < .001). All TEG parameters at 1-4 h and maximum amplitude (MA) at 18-30 h improved from baseline post-CP transfusion (p < .05) though improvements in K-time and MA were lower than LP (p < .05). DISCUSSION: During shortages, CP may supplement LP in prophylactic transfusions of thrombocytopenic patients.

Cold stored platelets in the management of bleeding: is it about bioenergetics?

When platelet concentrates (PCs) were first introduced in the 1960s as a blood component therapy, they were stored in the cold. As platelet transfusion became more important for the treatment of chemotherapy-induced thrombocytopenia, research into ways to increase supply intensified. During the late 1960s/early 1970s, it was demonstrated through radioactive labeling of platelets that room temperature platelets (RTP) had superior post-transfusion recovery and survival compared with cold-stored platelets (CSP). This led to a universal switch to room temperature storage, despite CSP demonstrating superior hemostatic effectiveness upon being transfused. There has been a global resurgence in studies into CSP over the last two decades, with an increase in the use of PC to treat acute bleeding within hospital and pre-hospital care. CSP demonstrate many benefits over RTP, including longer shelf life, decreased bacterial risk and easier logistics for transport, making PC accessible in areas where they have not previously been, such as the battlefield. In addition, CSP are reported to have greater hemostatic function than RTP and are thus potentially better for the treatment of bleeding. This review describes the history of CSP, the functional and metabolic assays used to assess the platelet storage lesion in PC and the current research, benefits and limitations of CSP. We also discuss whether the application of new technology for studying mitochondrial and glycolytic function in PC could provide enhanced understanding of platelet metabolism during storage and thus contribute to the continued improvements in the manufacturing and storage of PC.

What is the context? To transition into an activated state, platelets require a highly efficient source of energy that is met through the production of ATP ­ this is referred to as "platelet bioenergetics"Platelets can be removed from healthy donors and used to make platelet concentrates for clinical usePlatelet concentrates are used clinically either therapeutically (to halt bleeding) or prophylactically (to prevent bleeding in patients with low platelet counts)They are stored at room temperature (20­24^oC) with constant gentle agitation, in packs that allow gas exchange and have a 7-day shelf life in some jurisdictionsStoring platelets in the cold (2­6^oC) has historically been shown to improve their ability to halt bleedingWhat is new? There is a renewed interest in cold stored platelets for use in actively bleeding patientsThere are benefits to cold-storing platelets over room temperature storageCold stored platelets are licensed in the US and Norway for certain indications for 14 daysWhat is next? Cold stored platelets have the potential to improve logistics of clinical supply of platelets, enable supply of platelet concentrates where access is currently limited, such as pre-hospital care and on the battlefield and provide improved hemostatic effects for bleeding patients.New research measuring the bioenergetic profiles of cold stored platelets could advance understanding of metabolism in cold stored platelets and support decisions on their re-introduction on a wider scale.

Treatment of chemotherapy-induced thrombocytopenia in patients with non-hematologic malignancies.

Chemotherapy-induced thrombocytopenia (CIT) is a common complication of the treatment of non-hematologic malignancies. Many patient-related variables (e.g., age, tumor type, number of prior chemotherapy cycles, amount of bone marrow tumor involvement) determine the extent of CIT. CIT is related to the type and dose of chemotherapy, with regimens containing gemcitabine, platinum, or temozolomide producing it most commonly. Bleeding and the need for platelet transfusions in CIT are rather uncommon except in patients with platelet counts below 25x109/L in whom bleeding rates increase significantly and platelet transfusions are the only treatment. Nonetheless, platelet counts below 70x109/L present a challenge. In patients with such counts, it is important to exclude other causes of thrombocytopenia (medications, infection, thrombotic microangiopathy, post-transfusion purpura, coagulopathy and immune thrombocytopenia). If these are not present, the common approach is to reduce chemotherapy dose intensity or switch to other agents. Unfortunately decreasing relative dose intensity is associated with reduced tumor response and remission rates. Thrombopoietic growth factors (recombinant human thrombopoietin, pegylated human megakaryocyte growth and development factor, romiplostim, eltrombopag, avatrombopag and hetrombopag) improve pretreatment and nadir platelet counts, reduce the need for platelet transfusions, and enable chemotherapy dose intensity to be maintained. National Comprehensive Cancer Network guidelines permit their use but their widespread adoption awaits adequate phase III randomized, placebo-controlled studies demonstrating maintenance of relative dose intensity, reduction of platelet transfusions and bleeding, and possibly improved survival. Their potential appropriate use also depends on consensus by the oncology community as to what constitutes an appropriate pretreatment platelet count as well as identification of patient-related and treatment variables that might predict bleeding.

Successful phytotherapy for a patient with severe immune thrombocytopenia and failed with corticosteroids, azathioprine, eltrombopag, and platelet transfusion - A case report.

The purpose of this study was to investigate and evaluate the effectiveness of phytotherapy on a severe and complicated Immune Thrombocytopenia (ITP) patient who had failed with conventional treatments. A male patient presented with clinical symptoms of ITP and had been treated with Corticosteroids, Azathioprine, Eltrombopag, and platelet transfusions for over three years. The patient had an initial response but later developed severe complications, including hydrothorax, gastric pain, hematuria, and digestive hemorrhage, and no further response to treatment. The patient then received Phytotherapy for 17 months which significantly improved the clinical symptoms, platelet counts, and laboratory tests. Despite his active lifestyle, the patient was symptom-free with platelet counts ranging from 109 to 132×109/L.

Pathogen-reduced platelets in pediatric and neonatal patients: Demographics, transfusion rates, and transfusion reactions.

BACKGROUND: Pathogen-reduced platelets (PR PLT) are the emerging standard for proactive transfusion-transmitted infection (TTI) mitigation. There is, however, continued hesitation to transfuse PR PLT in children due to limited published data. We report demographics, rates of transfusion, and transfusion reactions (TR) associated with FDA-approved PR PLT in pediatric and neonatal patients at an academic medical center. METHODS: Retrospective review was performed for patients <18 years receiving at least one platelet over a 300-day period at a large, tertiary care hospital. Patients were transfused PR or conventional (CONV) PLT, based on inventory availability. Statistical analysis was performed using Fisher Exact Test. RESULTS: During the study period, 191 patients received 1010 platelet transfusions (892 units). Sixty-eight patients received PR PLT only (1.3 units/patient, 95% confidence interval [CI] 1.1-1.5; 1.8 transfusions/patient, 95% CI 1.4-2.2), and 56 patients received CONV PLT only (1.4 units/patient, 95% CI 1.1-1.7; 1.6 transfusions/patient, 95% CI 1.3-1.9). Patients with hematologic malignancies undergoing chemotherapy/radiation and allogeneic hematopoietic stem cell transplant received the most platelet transfusions and more commonly received both platelet types. Of 506 PR PLT units, 5 TRs occurred; 386 CONV PLT resulted in two TRs (p = .7052). Of 51 neonates, 37 received PR PLT without adverse events, including 13 receiving phototherapy. No TTIs were identified in any group. CONCLUSION: There was no significant difference in rates of transfusion or TRs between PR and CONV PLT. Our study provides additional evidence that PR PLT can be transfused to pediatric and neonatal patients without increasing the risk of acute adverse events.

Clinical and economic impacts of large volume delayed sampling and pathogen reduction technology platelet processing strategies in the United States.

BACKGROUND: Large volume delayed sampling (LVDS) and pathogen reduction technology (PRT) are strategies for platelet processing to minimize transfusion of contaminated platelet components (PCs). This study holistically compares the economic and clinical impact of LVDS and PRT in the United States. STUDY DESIGN AND METHODS: A decision model was constructed to simulate collection, processing, and use of PCs and to compare processing strategies: PRT with 5-day shelf life, LVDS with 7-day shelf life (LVDS7), and LVDS with 5-day shelf life extended to 7 days with secondary testing (LVDS5/2). Target population was adults requiring two or more transfusions. Collection, processing, storage, and distribution data were obtained from the National Blood Collection and Utilization Survey and published literature. Patient outcomes associated with transfusions were obtained from AABB guidelines, meta-analyses, and other published clinical studies. Costs were obtained from reimbursement schedules and other published sources. RESULTS: Given 10,000 donated units, 9512, 9511, and 9651 units of PRT, LVDS5/2, and LVDS7 PCs were available for transfusion, respectively. With these units, 1502, 2172, and 2329 transfusions can be performed with similar levels of adverse events. Assuming 30 transfusions a day, a hospital would require 69,325, 47,940, and 45,383 units of PRT, LVDS5/2, and LVDS7 platelets to perform these transfusions. The mean costs to perform transfusions were significantly higher with PRT units. CONCLUSIONS: Compared with PRT, LVDS strategies were associated with lower costs and higher PC availability while patients experienced similar levels of adverse events. Increased utilization of LVDS has the potential to improve efficiency, expand patient access to platelets, and reduce health care costs.

The Effectiveness and Safety of Platelet-Rich Plasma for Chronic Wounds: A Systematic Review and Meta-analysis.

OBJECTIVE: To evaluate the effectiveness and adverse events of autologous platelet-rich plasma (PRP) in individuals with lower-extremity diabetic ulcers, lower-extremity venous ulcers, and pressure ulcers. PATIENTS AND METHODS: We searched multiple databases from database inception to June 11, 2020, for randomized controlled trials and observational studies that compared PRP to any other wound care without PRP in adults with lower-extremity diabetic ulcers, lower-extremity venous ulcers, and pressure ulcers. RESULTS: We included 20 randomized controlled trials and five observational studies. Compared with management without PRP, PRP therapy significantly increased complete wound closure in lower-extremity diabetic ulcers (relative risk, 1.20; 95% CI, 1.09 to 1.32, moderate strength of evidence [SOE]), shortened time to complete wound closure, and reduced wound area and depth (low SOE). No significant changes were found in terms of wound infection, amputation, wound recurrence, or hospitalization. In patients with lower-extremity venous ulcers or pressure ulcers, the SOE was insufficient to estimate an effect on critical outcomes, such as complete wound closure or time to complete wound closure. There was no statistically significant difference in adverse events. CONCLUSION: Autologous PRP may increase complete wound closure, shorten healing time, and reduce wound size in individuals with lower-extremity diabetic ulcers. The evidence is insufficient to estimate an effect on wound healing in individuals with lower-extremity venous ulcers or pressure ulcers. TRIAL REGISTRATION: PROSPERO Identifier: CRD42020172817.

An Autologous Protein-Based Topical Ointment for Hard-to-Heal Skin Wounds: A Multiple Case Series.

BACKGROUND: There is increasing evidence regarding the wound healing potential of platelet-derived autologous by-products. We provide preliminary data regarding the use of a new plasma rich in growth factors-derived autologous topical ointment for the management of hard-to-heal wounds. CASES: Four patients suffering from difficult-to-heal wounds were treated with the autologous ointment. Within 2 to 8 weeks, all wounds healed completely with no signs of infection or functional impairment of the affected limbs. No adverse events were reported. CONCLUSION: Randomized and controlled trials are needed to determine the clinical efficacy of the autologous ointment. Nevertheless, results from this multiple case series indicate that this approach may be useful for accelerating the re-epithelization of difficult-to-heal wounds.

Combined Platelet and Erythrocyte Salvage: Evaluation of a New Filtration-based Autotransfusion Device.

BACKGROUND: The SAME device (i-SEP, France) is an innovative filtration-based autotransfusion device able to salvage and wash both red blood cells and platelets. This study evaluated the device performances using human whole blood with the hypothesis that the device will be able to salvage platelets while achieving a erythrocyte yield of 80% and removal ratios of 90% for heparin and 80% for major plasma proteins without inducing signification activation of salvaged cells. METHODS: Thirty healthy human whole blood units (median volume, 478 ml) were diluted, heparinized, and processed by the device in two consecutive treatment cycles. Samples from the collection reservoir and the concentrated blood were analyzed. Complete blood count was performed to measure blood cell recovery rates. Flow cytometry evaluated the activation state and function of platelets and leukocytes. Heparin and plasma proteins were measured to assess washing performance. RESULTS: The global erythrocyte yield was 88.1% (84.1 to 91.1%; median [25th to 75th]) with posttreatment hematocrits of 48.9% (44.8 to 51.4%) and 51.4% (48.4 to 53.2%) for the first and second cycles, respectively. Ektacytometry did not show evidence of erythrocyte alteration. Platelet recovery was 36.8% (26.3 to 43.4%), with posttreatment counts of 88 × 109/l (73 to 101 × 109/l) and 115 × 109/l (95 to 135 × 109/l) for the first and second cycles, respectively. Recovered platelets showed a low basal P-selectin expression at 10.8% (8.1 to 15.2%) and a strong response to thrombin-activating peptide. Leukocyte yield was 93.0% (90.1 to 95.7%) with no activation or cell death. Global removal ratios were 98.3% (97.8 to 98.9%), 98.2% (96.9 to 98.8%), and 88.3% (86.6 to 90.7%) for heparin, albumin, and fibrinogen, respectively. The processing times were 4.4 min (4.2 to 4.6 min) and 4.4 min (4.2 to 4.7 min) for the first and second cycles, respectively. CONCLUSIONS: This study demonstrated the performance of the SAME device. Platelets and red blood cells were salvaged without significant impact on cell integrity and function. In the meantime, leukocytes were not activated, and the washing quality of the device prevented reinfusion of high concentrations of heparin and plasma proteins.

Efficacy of autologous platelet-rich plasma in treating patients with burn wounds: A protocol for systematic review and meta-analysis.

BACKGROUND: Burns are still regarded among severe health problems related to high morbidity and mortality rates globally. In essence, health problems associated with burns can cause significant economic burden to society. Regardless of treatment available options, no best treatment was considered adequate for treating severe burns. In particular, only a few studies have focused on the effect of autologous platelet-rich plasma to treat burn wounds. The present study aim to systematically review existing literature to examine the effectiveness and safety of autologous platelet-rich plasma (PRP) to treat burn wounds. METHODS: For this study, we will conduct a systematic search using MEDLINE, EMBASE, the Cochrane Library, Web of Science, CINAHL, as well as Scopus to discover randomised controlled trials (RCTs) for the examination of effectiveness and safety of autologous PRP to treat burn wounds from their inception to March 2021 with no language restrictions. Additionally, we will search Google Scholar, ClinicalTrials.gov, as well as the reference lists of studies considered in the research to ascertain possibly eligible studies. We used two independent authors to evaluate studies for inclusion and conduct data extraction. We intend to assess study bias and quality utilizing the Cochrane Collaboration's Risk of Bias Tool 2.0. Also, we will pool study results using the fixed-effects model or random-effects model. Finally, any disagreements emanating from the process will be addressed through discussion or using a third author to mediate situations leading to disagreement. RESULTS: The study aims at assessing the effectiveness and safety of autologous PRP for treating burn wounds. CONCLUSION: The study will provide specific substantiation to assess autologous PRP's effectiveness and safety in treating patients with burn wounds. ETHICS AND DISSEMINATION: The study does not require ethical approval since no published studies are used in it. OSF REGISTRATION NUMBER: March 29, 2021.osf.io/74z5u. (https://osf.io/74z5u/).

Preventing adverse reactions in pediatric transfusions using washed platelet concentrate.

Blood transfusion is an important form of supportive care in children; however, transfusion-associated adverse reactions (TARs) are a problem. As with adults, allergic transfusion reactions (ATRs) and febrile non-hemolytic transfusion reactions (FNHTRs) are major TARs, and the frequency of ATRs caused by platelet concentrate (PC) tends to be particularly high. The plasma component of the blood product is thought to be a major factor in the onset of TARs such as ATR and FNHTR. By contrast, in children, age, underlying disease, and number of blood transfusions may be relevant patient-related factors. Although acetaminophen or diphenhydramine may be used prophylactically to prevent TARs, there is no clear evidence of their effectiveness. Volume-reduced PC is used to prevent TARs; however, it may be difficult to maintain the quality of platelets. Plasma-replaced PC stored with platelet additive solution raises the concern that TARs cannot be completely prevented by residual plasma. Washed PC removes most of the plasma, so it can effectively prevent ATR and FNHTR. The recent development of platelet additive solution [M-sol, bicarbonate Ringer's solution supplemented with acid-citrate-dextrose formula A (BRS-A)] in Japan has enabled the maintenance of the quality of platelets for long periods. The clinical use of washed PC in Japan has therefore progressed. Washed PC with M-sol or BRS-A for pediatric patients can effectively prevent TARs without diminishing the transfusion effect. The supply of washed PC has begun from the Japanese Red Cross Society, and it has become possible to use washed PC at all medical institutions in Japan.

Effectiveness of Autologous Platelet Concentrates in Management of Young Immature Necrotic Permanent Teeth-A Systematic Review and Meta-Analysis.

The use of autologous platelet concentrates (APCs) in regenerative endodontic procedures is inconsistent and unclear. The aim of this meta-analysis was to evaluate the effectiveness of autologous platelet concentrates compared to traditional blood-clot regeneration for the management of young, immature, necrotic, permanent teeth. The digital databases MEDLINE, SCOPUS, CENTRAL, Web of Science, and EMBASE were searched to identify ten randomized clinical trials. The outcomes at postoperative follow-up, such as dentinal wall thickness (DWT), increase in root length (RL), calcific barrier formation (CB), apical closure (AC), vitality response (VR), and success rate (SR), were subjected to both qualitative synthesis and quantitative meta-analysis. The meta-analysis showed that APCs significantly improved apical closure (risk ratio (RR) = 1.17; 95% CI: 1.01, 1.37; p = 0.04) and response to vitality pulp tests (RR = 1.61; 95% CI: 1.03, 2.52; p = 0.04), whereas no significant effect was observed on root lengthening, dentin wall thickness, or success rate of immature, necrotic teeth treated with regenerative endodontics. APCs could be beneficial when treating young, immature, necrotic, permanent teeth regarding better apical closure and improved response to vitality tests.

Platelet transfusion: Alloimmunization and refractoriness.

The transfusion of platelets for both prophylaxis and treatment of bleeding is relevant to all areas of medicine and surgery. Historically, guidance regarding platelet transfusion has been limited by a lack of good quality clinical trials and so has been based largely on expert opinion. In recent years however there has been renewed interest in methods to prevent and treat hemorrhage, and the field has benefited from a number of large clinical trials. Some studies, such as platelet transfusion versus standard care after acute stroke due to spontaneous cerebral haemorrhage associated with antiplatelet therapy (PATCH) and platelets for neonatal transfusion Study 2 (PLANET-2), have reported an increased risk of harm with platelet transfusion in specific patient groups. These studies suggest a wider role of platelets beyond hemostasis, and highlight the need for further clinical trials to better understand the risks and benefits of platelet transfusions. This review evaluates the indications for platelet transfusion, both prophylactic and therapeutic, in the light of recent studies and clinical trials. It highlights new developments in the fields of platelet storage and platelet substitutes, and novel ways to avoid complications associated with platelet transfusions. Lastly, it reviews initiatives designed to reduce inappropriate use of platelet transfusions and to preserve this valuable resource for situations where there is evidence for their beneficial effect.

The Effect of Autologous Platelet Concentrates on Maxillary Sinus Augmentation: A Meta-Analysis of Randomized Controlled Trials and Systematic Review.

INTRODUCTION: To assess the efficacy of the autologous platelet concentrates (APCs) combined with autologous bone or bone substitute for the maxillary sinus floor lifting by a meta-analysis. MATERIALS AND METHODS: Electronic databases (PUBMED, Web of Science, EMBASE through OVID, and Cochrane Library) were searched until Dec 31, 2019, and only randomized controlled trials (RCTs) in English were identified. Outcome variables included histologic evaluation, the implant stability quotient values, and radiographic evaluation. Data were analyzed by Revman5.3; the estimate of effect sizes was expressed as the 95% confidence interval; and the risk of bias was evaluated using the Cochrane Collaboration tool. RESULTS: 11 RCTs involving 141 patients (214 sites) were included in our meta-analysis, which indicated that the differences in the percentage of contact length among newly formed bone (2.61%, 95% CI, -1.18% to 7.09%), soft tissue area (-0.15%, 95% CI, -0.54% to 0.24%), and residual bone substitute material (-5.10%, 95% CI, -10.56% to 0.36%) in the APC group lacked statistical significance. Besides, there was the same effect on the implant stability quotient (ISQ) values of APC group who underwent implant placement 4 months after sinus augmentation and control group who received implant placement 8 months after sinus augmentation (-0.48, 95% CI, -1.68 to 0.72). No significant effect of APCs on the bone density was found (1.05%, 95% CI, -1.69% to 3.82%). CONCLUSIONS: The use of APCs in sinus augmentation may be further shorten the time required for bone graft maturation and allow earlier implant placement, but cannot enhance the bone formation in the long term. It is not currently recommended for routine use APCs as an osteoinductive material to bone grafting in sinus augmentation.

Low Risk of Traumatic Intracranial Hematoma Expansion with Factor Xa Inhibitors without Andexanet Reversal.

BACKGROUND: Andexanet alfa, a novel anticoagulation reversal agent for factor Xa inhibitors, was recently approved. Traumatic intracranial hemorrhage presents a prime target for this drug. The Novel Antidote to the Anticoagulation Effects of Factor Xa Inhibitors study established the efficacy of andexanet alfa in reversing factor Xa inhibitors. However, the association between anticoagulation reversal and traumatic intracranial hemorrhage progression is not well understood. The objective of this study was to determine progression rates of patients with traumatic intracranial hemorrhage on factor Xa inhibitors prior to hospitalization who were managed without the use of andexanet alfa. METHODS: A retrospective cohort study was performed between 2016 and 2019 at a single institution. An institutional traumatic brain injury (TBI) registry was queried. Patients with recorded use of apixaban or rivaroxaban <18 hours before injury were included. The primary study outcome was <35% increase in hemorrhage volume or thickness on repeated head computed tomography (CT) scans. RESULTS: We identified 25 patients meeting the inclusion criteria. Two patients were excluded because of a lack of necessary CT data. Twelve patients (52%) were receiving apixaban, and 11 were (48%) on rivaroxaban. On admission CT scan, 14 patients had subdural hematoma, 6 had traumatic intraparenchymal hemorrhage, and 3 had subarachnoid hemorrhage. Anticoagulation reversal was attempted in 17 patients (74%), primarily using 4-factor prothrombin complex concentrate. Twenty patients (87%) were adjudicated as having excellent or good hemostasis on repeat imaging. CONCLUSIONS: Our results indicate that patients on factor Xa inhibitors with complicated mild TBI have a similar intracranial hemorrhage progression rate to patients who are not anticoagulated or anticoagulated with a reversible agent. The hemostatic outcomes in our cohort were similar to those reported after andexanet alfa administration.

Retrospective cohort studies of repeat donors reveal donor-dependent variability in the recovery of transfused platelets.

BACKGROUND: The in vivo recovery of transfused platelets is variable and often unpredictable. Although many recipient-dependent factors are well described, donor-dependent variables remain poorly understood. STUDY DESIGN AND METHODS: To explore donor-dependent variables we conducted 2 retrospective studies of platelet transfusion outcomes in repeat donors. One study analyzed multiple autologous, radiolabeled platelet transfusions, and a second study analyzed multiple clinical platelet transfusions from a small cohort of repeat donors. RESULTS: In 36 subjects, multiple within-subject determinations of recovery and survival of radiolabeled autologous platelets revealed a relative consistency in platelet recoveries within donors compared to the range of recoveries among donors. Intraclass correlation coefficients for platelet recovery were 43% to 93%. In 524 ABO-compatible clinical platelet transfusions derived from seven donors, a linear mixed-effects model revealed significant donor-dependent differences in corrected count increments for units stored for 4 or 5 days. CONCLUSIONS: These two studies indicate reproducible donor-dependent differences in transfused platelet recovery, suggesting a possible heritable influence on the quality of transfused platelets.

Evaluation of the procoagulant properties of a newly developed platelet modified lysate product.

BACKGROUND: Platelet transfusion is associated with logistical problems with the national storage guidelines of platelets. This results in decreased function in vivo as a result of the platelet storage lesion, and complications such as allergic or hemolytic reactions and thrombosis. We evaluated a new, freshly prepared platelet modified lysate (PML) product designed to be more procoagulant than fresh and stored platelets. METHODS: Fresh platelets were concentrated, sonicated, and centrifuged to produce PML. Samples of both washed and unwashed PML were evaluated for particle size, concentration, and activity, and then tested for clot kinetics and thrombin generation. PML samples were also stored at various temperatures for durations up to 6 months and evaluated for clot kinetics and thrombin generation throughout. RESULTS: PML showed significantly higher concentration of platelet microparticles, increased procoagulant properties, and increased thrombin generation as compared to fresh and stored platelets. In addition, PML maintained its clot kinetics over a 6-month storage period with variable storage conditions. CONCLUSIONS: The newly proposed PML product is more procoagulant, stable, and has additional potential applications than currently available platelet products. Further studies will be performed to assess its functions in vivo and to assess thrombotic potential.

Autologous platelet-rich plasma treatment for patients with diabetic foot ulcers: a meta-analysis of randomized studies.

BACKGROUND: This study will explore the effectiveness and safety of autologous PRP in the treatment of patients with DFU. METHODS: The electronic databases of PubMed, EMBASE, BIOSIS, Cochrane central, and Google Scholar internet were searched updated on Jan 30, 2020. Evaluated outcomes included rate of complete ulcer healing, time to healing and adverse events. Statistical analysis was performed with RevMan 5.0 software and STATA 10.0 software. RESULTS: Ten RCTs with 456 patients were included in this study. The meta-analysis showed a higher complete ulcer healing rate (RR = 1.32, 95% CI 1.06 to 1.65, P = 0.01, I2 = 57%), a shorter healing time (MD = -23.42, 95% CI -37.33 to -9.51, P = 0.01, I2 = 78%), with no increasing the incidence of adverse events (RR = 0.48, 95% CI 0.22 to 1.05, P = 0.75, I2 = 0%) in PRP group compared with control. Mixed evidence was seen for publication bias, but analyses by using the trim-and-fill method did not appreciably alter results. CONCLUSION: Our findings suggest that autologous PRP may improve the complete ulcer healing rate, shorten the healing time, with no increasing the incidence of adverse events.

A report on the use of a single intra-articular administration of autologous platelet therapy in a naturally occurring canine osteoarthritis model - a preliminary study.

BACKGROUND: Osteoarthritis (OA) represents a significant burden to societies, as it affects quality of life, performance and poses a large healthcare cost. We aimed to describe the use of a single intra-articular (IA) injection of an autologous platelet therapy in the management of osteoarthritis (OA) in a naturally occurring canine model. METHODS: Fifteen police working dogs with bilateral hip OA were treated with 3 ml of platelet concentrate per hip joint, produced with the V-PET kit. Response to treatment was measured by the Canine Brief Pain Inventory (CBPI, divided in pain interference score - PIS, and Pain Severity Score - PSS), Liverpool Osteoarthritis in Dogs (LOAD), Canine Orthopedic Index (COI, divided in four dimensions: function, gait, stiffness and quality of life - QOL) and the Hudson Visual Analogue Scale (HVAS). Seven different time points were considered: T0 (before treatment), T1 (after 15 days), T2, T3, T4, T5 and T6 (after 1, 2, 3, 4 and 5 months respectively). Results from each evaluation moment were compared with T0 with a Paired Samples T-Test, and a p < 0.05 was set. RESULTS: Significant differences were observed at T1 (p < 0.01 for HVAS, PSS, COI, Gait and QOL; p = 0.01 for PIS; p = 0.02 for Function; and p < 0.05 for Stiffness), T2 (p < 0.01 for PSS, PIS and Gait; p = 0.01 for COI; p = 0.02 for HVAS, Function and QOL; and p = 0.04 for Stiffness), T3 (p < 0.01 for HVAS, PSS, PIS, Function and Gait; p = 0.01 for COI; and p = 0.02 for QOL), T4 (p < 0.01 for PSS; p = 0.03 for PIS and Gait), T5 (p < 0.01 for COI, Function and Gait; p = 0.03 for PSS, PIS and Stiffness), T6 (p < 0.01 for PSS, Function and Gait; p = 0.04 for PIS; p < 0.05 for COI) and T7 (p < 0.01 for PSS, Function and Gait; p = 0.01 for COI; and p < 0.05 for PIS). CONCLUSIONS: Autologous platelet therapy was used without apparent harm in the subjects. A single administration produced significant improvements, which lasted several months, and therefore warrants further study.