Expected individual benefit of prophylactic platelet transfusions in hemato-oncology patients based on bleeding risks
BACKGROUND Prophylactic platelet transfusions prevent bleeding in hemato-oncology patients, but it is unclear how any benefit varies between patients. Our aim was to assess if patients with different baseline risks for bleeding benefit differently from a prophylactic platelet transfusion strategy. STUDY DESIGN AND METHODS Using the data from the randomized controlled TOPPS trial (Trial of Platelet Prophylaxis), we developed a prediction model for World Health Organization grades 2, 3, and 4 bleeding risk (defined as at least one bleeding episode in a 30 days period) and grouped patients in four risk-quartiles based on this predicted baseline risk. Predictors in the model were baseline platelet count, age, diagnosis, disease modifying treatment, disease status, previous stem cell transplantation, and the randomization arm. RESULTS The model had a c-statistic of 0.58 (95% confidence interval [CI] 0.54-0.64). There was little variation in predicted risks (quartiles 46%, 47%, and 51%), but prophylactic platelet transfusions gave a risk reduction in all risk quartiles. The absolute risk difference (ARD) was 3.4% (CI -12.2 to 18.9) in the lowest risk quartile (quartile 1), 7.4% (95% CI -8.4 to 23.3) in quartile 2, 6.8% (95% CI -9.1 to 22.9) in quartile 3, and 12.8% (CI -3.1 to 28.7) in the highest risk quartile (quartile 4). CONCLUSION In our study, generally accepted bleeding risk predictors had limited predictive power (expressed by the low c-statistic), and, given the wide confidence intervals of predicted ARD, could not aid in identifying subgroups of patients who might benefit more (or less) from prophylactic platelet transfusion.
Haemato-oncology patients enrolled in the TOPPS trial (n= 600).
Platelet transfusions based on a threshold of 10 × 10 9/L (Prophylactic arm, n= 299).
Platelet transfusions in case of active bleeding (Therapeutic arm, n= 301).
47% of patients (279) developed at least one WHO grade 2, 3, or 4 bleeding during 30-day follow-up. The model had a c-statistic of 0.58. There was little variation in predicted risks (quartiles 46%, 47%, and 51%), but prophylactic platelet transfusions gave a risk reduction in all risk quartiles. The absolute risk difference was 3.4% in the lowest risk quartile (quartile 1), 7.4% in quartile 2, 6.8% in quartile 3, and 12.8% in the highest risk quartile (quartile 4).
Procedure-related bleeding risk in patients with cirrhosis and severe thrombocytopenia
European journal of clinical investigation. 2021;:e13508
BACKGROUND Gaps of knowledge still exist about the potential association between severe thrombocytopenia and increased risk of procedure-associated bleeding in patients with liver disease. METHODS In this narrative review we aimed at examining the association between procedure-related bleeding risk and platelet count in patients with cirrhosis and severe thrombocytopenia in various settings. We updated to 2020 a previously conducted literature search using MEDLINE/PubMed and EMBASE. The search string included clinical studies, adult patients with chronic liver disease and thrombocytopenia undergoing invasive procedures, any interventions and comparators, and haemorrhagic events of any severity as outcome. RESULTS The literature search identified 1,276 unique publications, 15 studies met the inclusion criteria and were analysed together with those identified by the previously search. Most of the new studies included in our analysis did not assess the association between post-procedural bleeding risk and platelet count alone in patients with chronic liver disease. Furthermore, some results could have been biased by prophylactic platelet transfusions. A few studies found that severe thrombocytopenia may be predictive of bleeding following percutaneous liver biopsy, dental extractions, percutaneous ablation of liver tumours, and endoscopic polypectomy. CONCLUSIONS Currently available literature cannot support definitive conclusions about the appropriate target platelet counts to improve the risk of bleeding in cirrhotic patients who underwent invasive procedures; moreover, it showed enormous variability in the use of prophylactic platelet transfusions.
An epitope-based approach of HLA-matched platelets for transfusion: a noninferiority crossover randomized trial
Platelet transfusion refractoriness results in adverse outcomes and increased health care costs. Managing refractoriness resulting from HLA alloimmunization necessitates the use of HLA antigen-matched platelets but requires a large platelet donor pool and does not guarantee full matching. We report the first randomized, double-blind, noninferiority, crossover trial comparing HLA epitope-matched (HEM) platelets with HLA standard antigen-matched (HSM) platelet transfusions. Alloimmunized, platelet-refractory, thrombocytopenic patients with aplastic anemia, myelodysplastic syndrome, or acute myeloid leukemia were eligible. HEM platelets were selected using HLAMatchMaker epitope (specifically eplet) matching. Patients received up to 8 prophylactic HEM and HSM transfusions provided in random order. The primary outcome was 1-hour posttransfusion platelet count increment (PCI). Forty-nine patients were randomized at 14 UK hospitals. For intention to treat, numbers of evaluable transfusions were 107 and 112 for HEM and HSM methods, respectively. Unadjusted mean PCIs for HEM and HSM methods were 23.9 (standard deviation [SD], 15) and 23.5 (SD, 14.1), respectively (adjusted mean difference, -0.1; 95% confidence interval [CI], -2.9 to 2.8). Because the lower limit of the 95% CI was not greater than the predefined noninferiority limit, the HEM approach was declared noninferior to the HSM approach. There were no differences in secondary outcomes of platelet counts, transfusion requirements, and bleeding events. Adequate 1-hour PCI was more frequently observed, with a mean number of 3.2 epitope mismatches, compared with 5.5 epitope mismatches for inadequate 1-hour increments. For every additional epitope mismatch, the likelihood of an adequate PCI decreased by 15%. Epitope-matched platelets should be considered to support HLA alloimmunized patients. This trial was registered at www.isrctn.com as #ISRCTN23996532.
Alloimmunized, platelet-refractory, thrombocytopenic patients with aplastic anemia, myelodysplastic syndrome, or acute myeloid leukemia (n= 49).
HLA epitope-matched (HEM) platelet transfusions.
HLA standard antigen-matched (HSM) platelet transfusions.
For intention to treat, numbers of evaluable transfusions were 107 and 112 for HEM and HSM methods, respectively. Unadjusted mean platelet count increments (PCI) for HEM and HSM methods were 23.9 (standard deviation [SD], 15) and 23.5 (SD, 14.1), respectively. There were no differences in secondary outcomes of platelet counts, transfusion requirements, and bleeding events. Adequate 1-hour PCI was more frequently observed, with a mean number of 3.2 epitope mismatches, compared with 5.5 epitope mismatches for inadequate 1-hour increments.
Risk of thrombocytopenia with Platelet-derived Growth Factor Receptor Kinase Inhibitors (PDGFR-TKIs) in cancer patients: A systematic review and meta-analysis of phase II/III randomized controlled trials
Journal of clinical pharmacology. 2021
We performed a systematic review and meta-analysis to fully investigate the thrombocytopenia of Platelet-derived Growth Factor Receptor Kinase Inhibitors (PDGFR-TKIs) in cancer patients. Databases were searched for randomized controlled trials (RCTs) treated with PDGFR-TKIs till January 2021. The relevant RCTs in cancer patients treated with PDGFR-TKIs were retrieved and the systematic evaluation was conducted. Nineteen RCTs and 3962 patients were included. Our study suggests that PDGFR-TKIs significantly increased the risks of all-grade (RR, 5.72; 95%CI, 4.32-7.59;p<0.00001; I(2) = 32%) and high-grade (RR, 5.65; 95%CI, 3.28- 9.75; p<0.00001; I(2) = 0%) thrombocytopenia in cancer patients. Sunitinib tend to be associated with the highest risk of thrombocytopenia among the included PDGFR-TKIs. The RR of high-grade thrombocytopenia varies significantly according to treatment line and median age. The available data suggested that the use of PDGFR-TKIs were associated with a significantly increased risk of thrombocytopenia. This article is protected by copyright. All rights reserved.
Platelet-rich fibrin: an autologous biomaterial for healing assistance of pharyngeal repair in total laryngectomy
European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery. 2020
OBJECTIVES The aim of this study was to evaluate the potential role of platelet-rich fibrin (PRF) application on the pharyngeal repair on decreasing the incidence of pharyngocutaneous fistula (PCF) after total laryngectomy. METHODS This randomized controlled clinical trial was conducted on 67 patients with advanced laryngeal carcinoma who underwent total laryngectomy, over 2 years in the Otorhinolaryngology Department, Mansoura University Hospitals, Egypt. Patients were randomly assigned into two groups: PRF group (n = 35) and control group (n = 32). Risk factors for development of PCF as well as the incidence of PCF were studied in both groups. RESULTS There was no statistically significant difference between groups regarding demographic data, medical comorbidities, basal hemoglobin and albumin levels, data related to the tumor (location, grade and TNM staging) and surgical details (preoperative tracheotomy and neck dissection). However, regarding the incidence of PCF, there was a statistically significant difference between groups as shown in Table 2. PCF was detected in 2/35 patients (5.7%) in the PRF group and in 10/32 patients (31.3%) in the control group (p = 0.004). CONCLUSION PRF application on the pharyngeal repair after total laryngectomy enhances the healing process and consequently decreases the incidence of PCF.
Autologous Platelet-Rich Gel for the Treatment of Diabetic Sinus Tract Wounds: A Clinical Study
The Journal of surgical research. 2019
BACKGROUND The aim of this study was to evaluate the efficacy of autologous platelet-rich gel (APG) in the treatment of deep sinus tract wounds from diabetic ulcers. METHODS Forty-eight patients with diabetic ulcers were randomly classified into two groups: an APG treatment group (25 patients) and a conventional wound dressing control group (23 patients). The sinus tract closure times, ulcer healing rates, hospitalization times, and hospitalization expenses of the two groups were compared. RESULTS There were no significant differences in the basic data and wound conditions between the two groups. The cure (healed wound) rates were 96% and 87% for the APG group and control group, respectively. During the first 4 wk, the sinus tract closure rate for the APG group was significantly higher than that for the control group. However, there was no significant difference in the sinus tract healing between the two groups at the end of the 8th wk. For the APG group and the control group, the average hospital stays were 19.36 +/- 7.239 d and 48.13 +/- 11.721 d, respectively, and the total hospitalization expenses were 2.48 +/- 0.45 ten thousand yuan and 5.63 +/- 1.35 ten thousand yuan (P < 0.05), respectively. These differences were statistically significant. CONCLUSIONS When compared with conventional wound dressings, APG can accelerate the healing of deep sinus tract wounds associated with diabetic ulcers.
Efficacy of cross-match compatible platelets in multi transfused haemato-oncology patients refractory to platelet transfusion
Transfusion and apheresis science : official journal of the World Apheresis Association : official journal of the European Society for Haemapheresis. 2019;:102657
BACKGROUND Platelet refractoriness, which leads to platelet transfusion failure resulting in significant morbidity and long hospital stay, is routinely not investigated. AIMS To determine the efficacy of cross-match compatible platelets in multi-transfused alloimmunized hemato-oncological patients refractory to platelet transfusion. MATERIALS AND METHOD 149 ABO compatible single donor apheresis platelet transfusions given to 38 alloimmunized refractory patients. Corrected Count Increment (CCI) <5000 (1h) was taken to define refractoriness. Solid-phase red cell adherence assay was used to determine the alloimmunization status and platelet cross-matching. Post Transfusion Platelet Increment, CCI and the Percentage Platelet Recovery were used to monitor the effectiveness of platelet transfusion. ANOVA test followed by Post hoc test Tukey HSD used to compare group means and classified into three groups depending upon the cross-matching and compatibility status. Categorical data was analysed for various outcomes using Pearson's chi square test or Fischer exact test. RESULT Patients showed statistically significant recovery in terms of PPI, CCI and PPR at 1h post SDAP transfusions when they received cross-matched compatible platelets. The one-hour CCI was significantly higher for cross-match-compatible platelets (19173+/-2692) than for incompatible (5888+/-1526) and for uncross-matched (8140+/-1480). Forty four (97.8%) of 45 cross-matched compatible platelet transfusion episodes showed a satisfactory response in terms of PPI and CCI values as compared to 50 % and 53.9% in uncross-matched group respectively (p<0.0001). CONCLUSION Platelet cross-matching is an effective intervention in the management of multi-transfused alloimmunized Haemato-oncological patients, refractory to platelet transfusion.
Preterm neonates benefit from low prophylactic platelet transfusion threshold despite varying risk of bleeding or death
The Platelets for Neonatal Thrombocytopenia (PlaNeT-2) trial reported an unexpected overall benefit of a prophylactic platelet transfusion threshold of 25x109/L compared to 50x109/L for major bleeding and/or mortality in preterm neonates (7% absolute risk reduction). However, some neonates in the trial may have experienced little benefit or even harm from the 25x109/L threshold. We aimed to assess this heterogeneity of treatment effect in the PlaNet-2 trial, in order to investigate whether all preterm neonates benefit from the low threshold. We developed a multivariable logistic regression model in the PlaNet-2 data to predict baseline risk of major bleeding and/or mortality for all 653 neonates. We then ranked the neonates based on their predicted baseline risk and categorized them into four risk quartiles. Within these quartiles we assessed absolute risk difference between the 50x109/L and 25x109/L threshold group. A total of 146 neonates died or developed major bleeding. The internally validated C-statistic of the model was 0.63 (95% confidence interval 0.58 - 0.68). The 25x109/L threshold was associated with absolute risk reduction in all risk groups, varying from 4.9% in the lowest to 12.3% in the highest risk group. These results suggest that a 25x109/L prophylactic platelet count threshold can be adopted in all preterm neonates, irrespective of predicted baseline outcome risk. Future studies are needed to improve the predictive accuracy of the baseline risk model. Current Controlled Trials number ISRCTN87736839.
Postnatal intervention for the treatment of FNAIT: a systematic review
Journal of perinatology : official journal of the California Perinatal Association. 2019
OBJECTIVE Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is associated with life-threatening bleeding. This systematic review of postnatal management of FNAIT examined transfusion of human platelet antigen (HPA) selected or unselected platelets, and/or IVIg on platelet increments, hemorrhage and mortality. STUDY DESIGN MEDLINE, EMBASE and Cochrane searches were conducted until 11 May 2018. RESULT Of 754 neonates, 382 received platelet transfusions (51%). HPA-selected platelets resulted in higher platelet increments and longer response times than HPA-unselected platelets. However, unselected platelets generally led to sufficient platelet increments to 30 x 10(9)/L, a level above which intracranial hemorrhage or other life-threatening bleeding rarely occurred. Platelet increments were not improved with the addition of IVIg to platelet transfusion. CONCLUSION Overall, HPA-selected platelet transfusions were more effective than HPA-unselected platelets but unselected platelets were often effective enough to achieve clinical goals. Available studies do not clearly demonstrate a benefit for addition of IVIg to platelet transfusion.
A systematic literature review on the use of platelet transfusions in patients with thrombocytopenia
Hematology (Amsterdam, Netherlands). 2019;24(1):679-719
Objective: Investigate globally, current treatment patterns, benefit-risk assessments, humanistic, societal and economic burden of platelet transfusion (PT). Methods: Publications from 1998 to June 27, 2018 were identified, based on databases searches including MEDLINE(R); Embase and Cochrane Database of Systematic Reviews. Data from studies meeting pre-specified criteria were extracted and validated by independent reviewers. Data were obtained for efficacy and safety from randomized controlled trials (RCTs); data for epidemiology, treatment patterns, effectiveness, safety, humanistic and societal burden from real-world evidence (RWE) studies; and economic data from both. Results: A total of 3425 abstracts, 194 publications (190 studies) were included. PT use varied widely, from 0%-100% of TCP patients; 1.7%-24.5% in large studies (>1000 patients). Most were used prophylactically rather than therapeutically. 5 of 43 RCTs compared prophylactic PT with no intervention, with mixed results. In RWE studies PT generally increased platelet count (PC). This increase varied by patient characteristics and hence did not always translate into a clinically significant reduction in bleeding risk. Safety concerns included infection risk, alloimmunization and refractoriness with associated cost burden. Discussion: In RCTs and RWE studies there was significant heterogeneity in study design and outcome measures. In RWE studies, patients receiving PT may have been at higher risk than those not receiving PT creating potential bias. There were limited data on humanistic and societal burden. Conclusion: Although PTs are used widely for increasing PC in TCP, it is important to understand the limitations of PTs, and to explore the use of alternative treatment options where available.