Platelet transfusions: trigger, dose, benefits, and risks

Impact of Thrombocytopenia on Preoperative Hematoma Expansion for Acute Traumatic Subdural Hematoma

BACKGROUND

Acute subdural hematoma is a neurosurgical emergency. Thrombocytopenia poses a management challenge for these patients. We aimed to determine the impact of thrombocytopenia on preoperative hemorrhage expansion and postoperative outcomes.

METHODS

This retrospective study evaluated patients presenting at our institution with acute subdural hematoma between 2009 and 2019. Patients who underwent surgery, had thrombocytopenia (platelets <150,000/μL), and had multiple preoperative computed tomography scans were included. Case control 1:1 matching was performed to generate a matched cohort with no thrombocytopenia. Univariate analyses were conducted to determine changes in subdural thickness and midline shift, postoperative Glasgow Coma Scale score, mortality, length of stay, and readmission rates.

RESULTS

We identified 19 patients with both thrombocytopenia and multiple preoperative computed tomography scans. Median platelet count was 112,000/μL (Q1 69,000, Q3 127,000). Comparing the thrombocytopenia cohort with the control group, there was a statistically significant difference in change in subdural thickness (median 5 mm [Q1 2, Q3 7.4] vs. 0 mm [Q1 0, Q3 1.5]; P = 0.001) and change in midline shift (median 3 mm [Q1 0, Q3 9.5] vs. median 0.5 mm [Q1 0, Q3 1.5]; P = 0.018). The thrombocytopenia cohort had higher in-hospital mortality (10 [52.6%] vs. 2 [10.5%]; P = 0.003). No significant differences were found in postoperative Glasgow Coma Scale score, length of stay, number of readmissions, and number of reoperations.

CONCLUSIONS

Thrombocytopenia is significantly associated with expansion of hematoma preoperatively in patients with acute subdural hematoma. While the benefit of early platelet correction cannot be determined from this study, patients who present with thrombocytopenia will benefit from close monitoring, a low threshold to obtain repeat imaging, and anticipating early surgical evacuation after platelet optimization.

Caulis Polygoni Multiflori Accelerates Megakaryopoiesis and Thrombopoiesis via Activating PI3K/Akt and MEK/ERK Signaling Pathways

Thrombocytopenia is one of the most common complications of cancer therapy. Until now, there are still no satisfactory medications to treat chemotherapy and radiation-induced thrombocytopenia (CIT and RIT, respectively). Caulis Polygoni Multiflori (CPM), one of the most commonly used Chinese herbs, has been well documented to nourish blood for tranquilizing the mind and treating anemia, suggesting its beneficial effect on hematopoiesis. However, it is unknown whether CPM can accelerate megakaryopoiesis and thrombopoiesis. Here, we employ a UHPLC Q–Exactive HF-X mass spectrometer (UHPLC QE HF-X MS) to identify 11 ingredients in CPM. Then, in vitro experiments showed that CPM significantly increased megakaryocyte (MK) differentiation and maturation but did not affect apoptosis and lactate dehydrogenase (LDH) release of K562 and Meg-01 cells. More importantly, animal experiments verified that CPM treatment markedly accelerated platelet recovery, megakaryopoiesis and thrombopoiesis in RIT mice without hepatic and renal toxicities in vivo. Finally, RNA-sequencing (RNA-seq) and western blot were used to determine that CPM increased the expression of proteins related to PI3K/Akt and MEK/ERK (MAPK) signaling pathways. On the contrary, blocking PI3K/Akt and MEK/ERK signaling pathways with their specific inhibitors suppressed MK differentiation induced by CPM. In conclusion, for the first time, our study demonstrates that CPM may be a promised thrombopoietic agent and provide an experimental basis for expanding clinical use.

Avatrombopag ethnic sensitivity analysis in chronic liver disease and thrombocytopenia patients: individual-level pooled analysis

INTRODUCTION

Few data have been published on the ethnic sensitivity of effectiveness, pharmacokinetics (PK), and pharmacodynamics (PD) of avatrombopag for the management of thrombocytopenia in patients with chronic liver disease (CLD).

METHODS

An ethnic sensitivity analysis was performed based on the results from two phase III studies (ADAPT-1 and ADAPT-2), with a primary endpoint of the proportion of patients without the requirement of platelet transfusion or rescue treatment for bleeding after randomization to 7 days following a scheduled procedure, and three phase I studies in healthy subjects. Cochran-Mantel-Haenszel and Fisher's exact tests were used to compare the differences in effectiveness in different ethnicities and overall population.

RESULTS

In total, 435 patients (placebo, n = 158; avatrombopag, n = 277) were stratified into various ethnic groups: 121 East Asians, including the subgroup of 27 Chinese, and 259 Caucasians. The proportion of patients who did not receive a platelet transfusion and those with a platelet count ⩾50 × 10⁹/L in the avatrombopag 40 and 60 mg groups were higher than that of placebo for all ethnicities and in the overall population. Statistical significance was obtained in the overall population and for all ethnicities other than Chinese patients, a group with a very small sample size. No significant difference was observed in the proportion of responders in each ethnic group compared to overall population (p > 0.05). The incidence of adverse events in East Asians was similar to that in both Caucasians and the overall population.

CONCLUSION

Avatrombopag was effective and safe in the management of thrombocytopenia in Chinese patients with CLD. Ethnicity does not appear to influence the efficacy, safety, PK, or PD of avatrombopag.

Bleeding disorders in implant dentistry: a narrative review and a treatment guide

Purpose

Considering a high prevalence of congenital and especially acquired bleeding disorders, their heterogeneity and the multitude of possible treatments strategies, a review of the scientific data on this topic is needed to implement a treatment guide for healthcare professionals.

Methods

A selective literature review was performed via PubMed for articles describing oral surgery / dental implant procedures in patients with congenital and acquired bleeding disorders. Out of the existing literature, potential treatment algorithms were extrapolated.

Results

In order to assess the susceptibility to bleeding, risk stratification can be used for both congenital and acquired coagulation disorders. This risk stratification, together with an appropriate therapeutic pathway, allows for an adequate and individualized therapy for each patient. A central point is the close interdisciplinary cooperation with specialists. In addition to the discontinuation or replacement of existing treatment modalities, local hemostyptic measures are of primary importance. If local measures are not sufficient, systemically administered substances such as desmopressin and blood products have to be used.

Conclusions

Despite the limited evidence, a treatment guide could be developed by means of this narrative review to improve safety for patients and practitioners. Prospective randomized controlled trials are needed to allow the implementation of official evidence-based guidelines.

Phase 2 study of avatrombopag in Japanese patients with chronic liver disease and thrombocytopenia

AIM

Avatrombopag, a thrombopoietin receptor agonist, can reduce the need for platelet transfusions or rescue interventions for bleeding in patients with chronic liver disease (CLD) and thrombocytopenia undergoing scheduled procedures. A model analysis indicated that the effect of avatrombopag on platelet production was reduced in East Asian versus non-East Asian patients; however, the difference was deemed not clinically significant. Furthermore, a subgroup analysis of pooled Phase 3 trials showed similar avatrombopag efficacy across racial subgroups. The aim of this Phase 2 study was to corroborate the efficacy and safety of avatrombopag in Japanese patients with thrombocytopenia due to CLD.

METHODS

Japanese patients with CLD and thrombocytopenia were randomized to receive placebo or avatrombopag 20, 40, or 60 mg daily for 5 days. The primary endpoint was responder rate in platelet counts at Visit 4 (10-13 days after treatment initiation), defined as the proportion of patients with platelet count ≥50 × 10⁹ /L and ≥20 × 10⁹ /L increase from baseline.

RESULTS

Thirty-nine patients were randomized and completed the study (placebo, n = 11; avatrombopag 20 mg, n = 7; 40 mg, n = 11; 60 mg, n = 10). Avatrombopag treatment was associated with significant increases in responder rate at Visit 4 in the 40 mg (63.6%; p = 0.004) and 60 mg (40%; p = 0.024) groups versus placebo (9.1%). Avatrombopag was well tolerated and no new safety signals were detected.

CONCLUSIONS

Efficacy and safety results from this study were consistent with previous studies in patients with CLD and thrombocytopenia undergoing elective procedures, supporting treatment with avatrombopag in the Japanese population.

CLINICALTRIALS

gov identifier: NCT02227693.

Carica papaya ameliorates thrombocytopenia through upregulation of Interleukin-11 and modulation of thrombopoietin in mouse model of carboplatin-induced myelosuppression

INTRODUCTION

Carica papaya L. (C. papaya) is used as a folk medicine for the treatment of various diseases throughout the world. Recently, papaya leaves decoction has been effectively used for the prevention and treatment of thrombocytopenia. The current study was undertaken to evaluate the thrombopoietic and immunomodulatory activities of C. papaya leaves in the mouse model of carboplatin induced myelosuppression.

METHODS

Myelosuppression was induced by a single intraperitoneal injection of carboplatin (125 mg/kg b. w.). Aqueous extract of C. papaya leaves (15 mg/kg b. w.) was given orally by feeding tube from day 0-18 to preventive group to see the preventive effect and from day 6-18 to treatment group for treatment effect.

RESULTS

The results showed that the C. papaya leaves extract significantly decreased the fall in platelet count in preventive and treatment groups. Extract significantly prevented the fall in total WBCs count on day 12 and 18 in the preventive group, whereas it significantly elevated the WBCs count in treatment group on day 18. Significantly increased RBCs count in both groups was observed on day 18 after treatment with C. papaya leaves extract. Treatment with C. papaya leaves extract significantly upregulated the mRNA expression levels of thrombopoietic cytokine IL-11 in both preventive and treatment groups. It is also observed that restoration of normal platelet count might have been resulted owing to the synergistic effect of upregulated IL-11 which ultimately led to a significantly diminished TPO expression.

CONCLUSION

Our data suggest that aqueous extract of C. papaya leaves possesses significant preventive and curative properties against thrombocytopenia.

Proposed protocol for treatment of severe periodontitis without platelet transfusion in patients with aplastic anemia: a case report

Background

Aplastic anemia is an intractable disease characterized by pancytopenia, susceptibility to infection, and difficulty in achieving hemostasis. In patients with severe periodontal disease and aplastic anemia, spontaneous bleeding from the gingival tissue due to thrombocytopenia and during brushing is common, which may further exacerbate dental issues. Comprehensive periodontal treatment for patients with aplastic anemia is highly challenging and requires collaboration with a hematologist. Here, we discuss the case of a patient with aplastic anemia and severe periodontitis who was successfully treated in collaboration with our hematology department.

Case presentation

A 36-year-old Japanese woman with chief complaints of spontaneous gingival bleeding, pain, and increasing tooth mobility consulted our department. She had developed pancytopenia at age 11 years and was later diagnosed with aplastic anemia, making her susceptible to infection due to leukopenia. The results of the initial periodontal examination led to a diagnosis of severe generalized periodontitis (generalized stage IV grade C periodontitis) caused by leukopenia and poor oral hygiene. We adopted a comprehensive treatment plan, including invasive dental procedures. The patient exhibited no postoperative bleeding due to aplastic anemia-induced thrombocytopenia and experienced a good outcome.

Conclusions

Both physicians and dentists should be aware that immunocompromised patients with aplastic anemia are at risk of developing severe periodontitis with severe alveolar bone resorption if the condition is combined with poor oral hygiene. Even in the presence of aplastic anemia, patients with severe periodontitis can undergo comprehensive dental treatment, including dental extraction and periodontal surgery, if bleeding and susceptibility to infection are controlled. This requires the cooperation of the patient and hematologists and can ultimately contribute to improving the patient’s quality of life.

Treatment algorithm for thrombocytopenia in patients with chronic liver disease undergoing planned invasive procedures

Thrombocytopenia is highly prevalent in patients with chronic liver disease (CLD) and these patients often require invasive procedures that carry a risk of bleeding. To prevent bleeding, guidelines recommend increasing platelet counts in patients with CLD who have thrombocytopenia and are planned to undergo invasive procedures. There are currently two options to increase platelet counts in patients in this setting: platelet transfusion or thrombopoietin receptor agonists (TPORAs). Several treatment algorithms have been developed in the US to help physicians choose the best course of treatment for each patient; however, to date, no such algorithm has been proposed in other countries, where the choice of treatment has been based on each physician's judgment and experience. Here, we discuss the pathogenesis and treatment of thrombocytopenia in patients with CLD, we review and present current evidence of the efficacy of TPORAs for the treatment of thrombocytopenia in patients with CLD, and we present our expert opinion on a Japanese treatment algorithm for thrombocytopenia in patients with CLD who are planned to undergo invasive procedures. This algorithm aims to provide guidance for optimal decision making in the selection of TPORA therapy or platelet transfusion based on the latest evidence and according to actual clinical practice.

Avatrombopag: A Review in Thrombocytopenia

Avatrombopag (Doptelet^®) is an orally administered second generation thrombopoietin receptor agonist (TPO-RA) approved for the treatment of primary chronic immune thrombocytopenia (ITP) in adult patients who are refractory or have an unsatisfactory response to other treatments, as well as for the treatment of thrombocytopenia in adult patients with chronic liver disease (CLD) scheduled to undergo an invasive procedure. In phase III studies, avatrombopag was associated with a significantly greater platelet response than placebo in patients with chronic ITP, and was superior to placebo in reducing the requirement for platelet transfusion or rescue procedures for bleeding caused by surgery in patients with CLD with a platelet count < 50 × 10⁹/L at baseline. Longer term data indicate that avatrombopag is associated with high durable response rates in ITP and may have corticosteroid-sparing effects. The drug was generally well tolerated in both indications. Avatrombopag thus represents a convenient and effective second-line treatment for patients with chronic ITP and can prevent bleeding events in patients with CLD scheduled to undergo a procedure, offering a useful alternative to other available treatments in both indications.

Avatrombopag (Doptelet^®) is an orally administered drug that mimics the natural compound (thrombopoietin) responsible for stimulating the production of platelets, an essential component of the clotting process that prevents excessive bleeding. Several conditions can cause reduced platelet levels (thrombocytopenia) to the point that intervention is needed to prevent excessive blood loss. Avatrombopag is approved for the treatment of primary chronic immune thrombocytopenia (ITP) and to prevent bleeding caused by surgery in patients with low platelet levels caused by chronic liver disease (CLD). Clinical trials in patients with ITP show that avatrombopag quickly increases platelet levels and that this increase is maintained in the longer term in many patients. Similarly, clinical trials in patients with low platelet levels because of CLD showed that giving avatrombopag prior to surgery reduced the need for platelet transfusions or rescue procedures for bleeding. Avatrombopag is thus a convenient and effective treatment for patients with chronic ITP and can prevent bleeding events in patients with CLD scheduled to undergo a procedure. In both indications avatrombopag offers a useful alternative to other available treatments.

Preoperative platelet transfusions: A retrospective review of pediatric patients with thrombocytopenia, 2011-2016

BACKGROUND

Thrombocytopenia is a common perioperative clinical problem and preoperative platelet transfusion prior to surgery is standard practice. Recent platelet trials and literature reviews have found no association between platelet count and bleeding incidence except when platelet count is extremely low. Our aim was to evaluate the bleeding risk and the overall platelet transfusion management among pediatric patients with severe thrombocytopenia based on whether they were preoperatively transfused versus transfused at time of incision.

METHODS

This is a retrospective analysis of pediatric patients with a platelet count ≤50 × 10⁹/L in the 12 h prior to surgery at a single tertiary pediatric hospital from 2011 to 2016. Eligible patients were ≤21 years old. Patients with necrotizing enterocolitis and neonates were excluded. The primary outcome was postoperative bleeding complications. Additional outcomes were preoperative platelet change and weight adjusted transfusion volumes.

RESULTS

A total of 37 patients were included in this analysis of which 29 (78%) received preoperative platelet transfusions within 12 h prior to surgery. No postoperative bleeding complications occurred 30 days after operation, regardless of preoperative transfusion status. There was no significant difference in platelet change by preoperative transfusion status and preoperative transfusion volume was a poor predictor of change in preoperative platelet count (crude: r²=0.19, age/gender adjusted: r²=0.48).

CONCLUSION

Patients transfused at time of surgical procedure did not have an increased risk of bleeding over those preoperatively transfused. This finding is in agreement with previous studies in adult populations, supporting the safety of deferring platelet transfusions until the time of incision for thrombocytopenic pediatric surgical patients.

LEVEL OF EVIDENCE

III.

Progress in the production of haematopoietic stem and progenitor cells from human pluripotent stem cells

Cell therapies are currently used to treat many haematological diseases. These treatments range from the long-term reconstitution of the entire haematopoietic system using the most potent haematopoietic stem cells (HSCs) to the short-term rescue with mature functional end cells such as oxygen-carrying red blood cells and cells of the immune system that can fight infection and repair tissue. Limitations in supply and the risk of transmitting infection has prompted the design of protocols to produce some of these cell types from human pluripotent stem cells (hPSCs). Although it has proven challenging to generate the most potent HSCs directly from hPSCs, significant progress has been made in the development of differentiation protocols that can successfully produce haematopoietic progenitor cells and most of the mature cell lineages. We review the key steps used in the production of haematopoietic stem and progenitor cells (HSPCs) from hPSCs and the cell surface markers and reporter strategies that have been used to define specific transitions. Most studies have relied on the use of known markers that define HSPC production in vivo but more recently single cell RNA sequencing has allowed a less biased approach to their characterisation. Transcriptional profiling has identified new markers for naïve and committed hPSC-derived HSPC populations and trajectory analyses has provided novel insights into their lineage potential. Direct comparison of in vitro- and in vivo-derived RNA single cell sequencing datasets has highlights similarities and differences between the two systems and this deeper understanding will be key to the design and the tracking of improved and more efficient differentiation protocols.

Exploratory composite endpoint demonstrates benefit of trilaciclib across multiple clinically meaningful components of myeloprotection in patients with small cell lung cancer

Chemotherapy-induced myelosuppression is an acute, dose-limiting toxicity of chemotherapy regimens used in the treatment of extensive-stage small cell lung cancer (ES-SCLC). Trilaciclib protects haematopoietic stem and progenitor cells from chemotherapy-induced damage (myeloprotection). To assess the totality of the myeloprotective benefits of trilaciclib, including analysis of several clinically relevant but low-frequency events, an exploratory composite endpoint comprising five major adverse haematological events (MAHE) was prospectively defined: all-cause hospitalisations, all-cause chemotherapy dose reductions, febrile neutropenia (FN), prolonged severe neutropenia (SN) and red blood cell (RBC) transfusions on/after Week 5. MAHE and its individual components were assessed in three randomised, double-blind, placebo-controlled Phase 2 trials in patients receiving a platinum/etoposide or topotecan-containing chemotherapy regimen for ES-SCLC and in data pooled from the three trials. A total of 242 patients were randomised across the three trials (trilaciclib, n = 123; placebo, n = 119). In the individual trials and the pooled analysis, administering trilaciclib prior to chemotherapy resulted in a statistically significant reduction in the cumulative incidence of MAHE compared to placebo. In the pooled analysis, the cumulative incidences of all-cause chemotherapy dose reductions, FN, prolonged SN and RBC transfusions on/after Week 5 were significantly reduced with trilaciclib vs placebo; however, no significant difference was observed in rates of all-cause hospitalisations. Additionally, compared to placebo, trilaciclib significantly extended the amount of time patients remained free of MAHE. These data support the myeloprotective benefits of trilaciclib and its ability to improve the overall safety profile of myelosuppressive chemotherapy regimens used to treat patients with ES-SCLC.

Trilaciclib prior to chemotherapy and atezolizumab in patients with newly diagnosed extensive-stage small cell lung cancer: A multicentre, randomised, double-blind, placebo-controlled Phase II trial

Trilaciclib is an intravenous CDK4/6 inhibitor administered prior to chemotherapy to preserve haematopoietic stem and progenitor cells and immune system function from chemotherapy-induced damage (myelopreservation). The effects of administering trilaciclib prior to carboplatin, etoposide and atezolizumab (E/P/A) were evaluated in a randomised, double-blind, placebo-controlled Phase II study in patients with newly diagnosed extensive-stage small cell lung cancer (ES-SCLC) (NCT03041311). The primary endpoints were duration of severe neutropenia (SN; defined as absolute neutrophil count <0.5 × 109 cells per L) in Cycle 1 and occurrence of SN during the treatment period. Other endpoints were prespecified to assess the effects of trilaciclib on additional measures of myelopreservation, patient-reported outcomes, antitumour efficacy and safety. Fifty-two patients received trilaciclib prior to E/P/A and 53 patients received placebo. Compared to placebo, administration of trilaciclib resulted in statistically significant decreases in the mean duration of SN in Cycle 1 (0 vs 4 days; P < .0001) and occurrence of SN (1.9% vs 49.1%; P < .0001), with additional improvements in red blood cell and platelet measures and health-related quality of life (HRQoL). Trilaciclib was well tolerated, with fewer grade ≥3 adverse events compared with placebo, primarily due to less high-grade haematological toxicity. Antitumour efficacy outcomes were comparable. Administration of trilaciclib vs placebo generated more newly expanded peripheral T-cell clones (P = .019), with significantly greater expansion among patients with an antitumour response to E/P/A (P = .002). Compared with placebo, trilaciclib administered prior to E/P/A improved patients' experience of receiving treatment for ES-SCLC, as shown by reduced myelosuppression, and improved HRQoL and safety profiles.

Controlling Surface-Induced Platelet Activation by Agarose and Gelatin-Based Hydrogel Films

Platelet-surface interaction is of paramount importance in biomedical applications as well as in vitro studies. However, controlling platelet-surface activation is challenging and still requires more effort as they activate immediately when contacting with any nonphysiological surface. As hydrogels are highly biocompatible, in this study, we developed agarose and gelatin-based hydrogel films to inhibit platelet-surface adhesion. We found promising agarose films that exhibit higher surface wettability, better controlled-swelling properties, and greater stiffness compared to gelatin, resulting in a strong reduction of platelet adhesion. Mechanical properties and surface wettability of the hydrogel films were varied by adding magnetite (Fe3O4) nanoparticles. While all of the films prevented platelet spreading, films formed by agarose and its nanocomposite repelled platelets and inhibited platelet adhesion and activation stronger than those of gelatin. Our results showed that platelet-surface activation is modulated by controlling the properties of the films underneath platelets and that the bioinert agarose can be potentially translated to the development of platelet storage and other medical applications.

Preoperative Platelet and International Normalized Ratio Thresholds and Risk of Complications After Primary Hip Fracture Surgery

BACKGROUND

A paucity of data exists on safe platelet and international normalized ratio (INR) thresholds for hip fracture surgery. Recent work has called into question the safety of preoperative INRs < 1.5 for total knee arthroplasty, and optimal platelet thresholds are unknown. The purpose of this study was to identify the risk of 30-day postoperative morbidity and mortality in patients with thrombocytopenia or elevated INRs undergoing hip fracture surgery.

METHODS

The National Surgical Quality Improvement Program database was queried for patients undergoing surgical treatment of a native hip fracture from 2012 to 2017 (N = 86,850). Patient demographic, laboratory, and complication data were collected. Patients with preoperative platelet counts or INRs within one day of surgery were included for analysis. Preoperative platelet counts and INRs were divided into four groups (<50 k/μL, ≥50 k to 100 k/μL, ≥100 k to 150 k/μL, ≥150 k/μL, and ≤1.0, >1.0 to 1.5, >1.5 to 2.0, and >2.0, respectively). Multivariable logistic regressions were used to assess the independent association between platelet count and INR on bleeding complications requiring transfusion, wound complications, reoperations, readmissions, and deaths.

RESULTS

A total of 72,306 and 56,027 patients were included for analysis of preoperative platelet and INR levels, respectively. In reference to platelet levels ≥150 k/μL, a notably increased risk of bleeding events was observed for patients with platelet counts ≥100 k to 150 k/μL (odds ratio [OR] 1.21, 95% confidence interval 1.15 to 1.27), ≥50 to 100 k/μL (OR 1.85, 1.69 to 2.03), and <50 k/μL (OR 1.60, 1.25 to 2.04). Decreasing platelet counts were associated with a stepwise increased risk of mortality from OR 1.12 (1.02 to 1.22) for platelet counts ≥100 k to 150 k/μL to OR 1.63 (1.41 to 1.90) and OR 1.59 (1.06 to 2.39) for platelet counts ≥50 k to 100 k/μL and <50 k/μL, respectively. Elevated INR was associated with an increased risk of reoperations, readmissions, and death (P < 0.001 for all), with largest effect sizes observed starting at INRs >1.5.

DISCUSSION

The results of this study suggest that preoperative platelet thresholds of <100,000/μL and INR thresholds of 1.5 serve as an important risk factor for complications after hip fracture surgery. Future work is warranted to determine whether preoperative platelet transfusions and/or INR reversal will improve outcomes for these patients.

LEVEL OF EVIDENCE

Prognostic Level III.

Thrombocytopenia and Hemostatic Changes in Acute and Chronic Liver Disease: Pathophysiology, Clinical and Laboratory Features, and Management

Thrombocytopenia, defined as a platelet count <150,000/μL, is the most common complication of advanced liver disease or cirrhosis with an incidence of up to 75%. A decrease in platelet count can be the first presenting sign and tends to be proportionally related to the severity of hepatic failure. The pathophysiology of thrombocytopenia in liver disease is multifactorial, including (i) splenomegaly and subsequently increased splenic sequestration of circulating platelets, (ii) reduced hepatic synthesis of thrombopoietin with missing stimulation both of megakaryocytopoiesis and thrombocytopoiesis, resulting in diminished platelet production and release from the bone marrow, and (iii) increased platelet destruction or consumption. Among these pathologies, the decrease in thrombopoietin synthesis has been identified as a central mechanism. Two newly licensed oral thrombopoietin mimetics/receptor agonists, avatrombopag and lusutrombopag, are now available for targeted treatment of thrombocytopenia in patients with advanced liver disease, who are undergoing invasive procedures. This review summarizes recent advances in the understanding of defective but at low level rebalanced hemostasis in stable cirrhosis, discusses clinical consequences and persistent controversial issues related to the inherent bleeding risk, and is focused on a risk-adapted management of thrombocytopenia in patients with chronic liver disease, including a restrictive transfusion regimen.

Latest culture techniques: cracking the secrets of bone marrow to mass-produce erythrocytes and platelets ex vivo

Since the dawn of medicine, scientists have carefully observed, modeled and interpreted the human body to improve healthcare. At the beginning there were drawings and paintings, now there is three-dimensional modeling. Moving from two-dimensional cultures and towards complex and relevant biomaterials, tissue-engineering approaches have been developed in order to create three-dimensional functional mimics of native organs. The bone marrow represents a challenging organ to reproduce because of its structure and composition that confer it unique biochemical and mechanical features to control hematopoiesis. Reproducing the human bone marrow niche is instrumental to answer the growing demand for human erythrocytes and platelets for fundamental studies and clinical applications in transfusion medicine. In this review, we discuss the latest culture techniques and technological approaches to obtain functional platelets and erythrocytes ex vivo. This is a rapidly evolving field that will define the future of targeted therapies for thrombocytopenia and anemia, but also a long-term promise for new approaches to the understanding and cure of hematologic diseases.

Assessing the periprocedural magnitude of platelet count change in response to lusutrombopag

BACKGROUND & AIMS

Despite limitations, platelet transfusion has been used to minimise bleeding risk in patients with thrombocytopaenia. Lusutrombopag is an oral, thrombopoietin receptor agonist approved for treatment of thrombocytopaenia associated with chronic liver disease in patients undergoing planned invasive procedures. This post-hoc analysis assessed the magnitude of platelet count change based on the integrated per-protocol population from 2 similar phase III multicentre, randomised, double-blind, placebo-controlled trials.

METHODS

Adults with chronic liver disease-induced thrombocytopaenia and platelet count <50 (× 109/L) received lusutrombopag 3 mg or placebo ≤7 days before invasive procedure scheduled 9-14 days after randomisation. Platelet transfusion was required per protocol if the platelet count remained <50 no more than 2 days before the planned invasive procedure. Post-hoc analysis included: proportion of patients with platelet count ≥50, ≥1.5-fold increase, and a doubling of platelet count; maximum and maximum change in platelet count; and platelet count time course.

RESULTS

Platelet count ≥50, a platelet count increase ≥1.5-fold, and at least a doubling in platelet count were achieved in 88.3%, 86.9%, and 52.6% of patients in the lusutrombopag group (n = 137) vs. 58.6%, 32.3%, and 6.0% of patients in the placebo group (n = 133), respectively. In the lusutrombopag group, median maximum platelet count across baseline platelet counts of <30, ≥30 to <40, and ≥40 was 46, 76, and 87, respectively. Median maximum change in platelet count by baseline platelet count was +24, +42, and +40, respectively. Patients who received lusutrombopag without platelet transfusion achieved a median platelet count ≥50 for 3 weeks.

CONCLUSIONS

Patients treated with lusutrombopag experienced a clinically relevant response in platelet count for a substantial duration of time.

LAY SUMMARY

Patients with low platelet counts caused by chronic liver disease may not receive planned invasive procedures or surgeries because of an increased risk of bleeding. Lusutrombopag has previously demonstrated efficacy in raising platelet counts and is approved to treat chronic liver disease patients with low platelet counts in advance of a planned surgery. Physicians need to understand more clearly what to expect in terms of platelet count change when using lusutrombopag; this integrated analysis provides data to help guide its clinical application.

Activity-based cost of platelet transfusions in medical and surgical inpatients at a US hospital

BACKGROUND AND OBJECTIVES

Previous studies by the Cost of Blood Consensus Conference (COBCON) have used a comprehensive, standardized and generalizable activity-based costing (ABC) model to estimate the cost of red blood cell transfusions and plasma transfusion. The objective of this study was to determine the total cost of platelet transfusions in a real-world US hospital inpatient setting.

MATERIALS AND METHODS

This database analysis study retrospectively collected costs for all activities related to platelet transfusion in a single-acute care US teaching hospital in 2017. Costs were collected in a stepwise manner using a custom ABC model which mapped the technical, administrative and clinical processes involved in the transfusion of platelets.

RESULTS

For the 15 024 inpatients included in the analysis, 6335 (42·2%) were given a blood type and screen, and 941 (6·3%) received a transfusion of one or more blood products. A total of 333 platelet units were transfused in 131 patients (mean 2·54 units per patient): 211 (63·4%) units in medical inpatients and 122 (36·6%) in surgical inpatients. The total cost was $1359·99 per platelet unit, corresponding to $3457·06 per inpatient. Acquisition costs made up the largest proportion of the total cost (45·1%) followed by direct and indirect overheads (38·7%) and hospital processes costs (16·3%).

CONCLUSION

This is the first study to use an ABC costing model to determine the full cost of platelet transfusions within a US inpatient setting. This provides a useful reference point for comparisons with other transfusion products, and considerations for cost reduction.

A qualitative exploration of the factors influencing the decision to transfuse elective platelets in cancer care

OBJECTIVES

To explore factors contributing to decisions to transfuse platelets in cancer care outside guidelines using case study methods.

METHODS

Two case studies were examined, using instrumental case study methodology, to qualitatively explore factors that influence the decision to transfuse platelets. Interviews (n=10) were conducted around cases in haematology and critical care. In-depth review of documentary evidence was undertaken and propositions were developed to provide rigour during the investigation. Thematic analysis and triangulation of documents was undertaken to find specific factors, and propositions analysed, as per instrumental case study methods.

RESULTS

Both cases emphasised how patient complexity, and individual response to platelet administration, was an influencing factor. Other themes included uncertainty of clinical situations coupled with uncertainty about platelet availability. Other factors worthy of further investigation include the concept of professional safety and the trustworthiness of platelet thresholds against platelet monitoring for bleeding episodes.

CONCLUSION

The findings indicated several factors influence decisions to transfuse, including clinical context, and individual ability to trust guidelines and assume any perceived risks.

Trilaciclib dose selection: an integrated pharmacokinetic and pharmacodynamic analysis of preclinical data and Phase Ib/IIa studies in patients with extensive-stage small cell lung cancer

Purpose

Trilaciclib is a first-in-class CDK4/6 inhibitor that transiently arrests hematopoietic stem and progenitor cells (HSPCs) in the G1 phase of the cell cycle to preserve them from chemotherapy-induced damage (myelopreservation). We report integrated analyses of preclinical and clinical data that informed selection of the recommended Phase II dose (RP2D) used in trilaciclib trials in extensive-stage small cell lung cancer (ES-SCLC).

Methods

A semi-mechanistic pharmacokinetic/pharmacodynamic (PK/PD) model developed from preclinical data guided selection of an optimal dose for G1 bone marrow arrest in a first-in-human Phase I study (G1T28-1-01). PK, PD, safety, and efficacy data from G1T28-1-01 and two Phase Ib/IIa studies (G1T28-02/-03) in ES-SCLC were analyzed to support RP2D selection.

Results

Model simulation of bone marrow arrest based on preclinical data predicted that a ≥ 192 mg/m² dose would induce a 40–50% decrease in total bone marrow proliferation in humans and almost 100% cell cycle arrest of cycling HSPCs. Consistent with this model, analysis of bone marrow aspirates in healthy volunteers after trilaciclib 192 mg/m² administration demonstrated almost 100% G1 arrest in HSPCs and 40% decrease in total bone marrow proliferation, with minimal toxicity. G1T28-02/-03 reported similar PK parameters with trilaciclib 200 mg/m² but slightly lower exposures than expected compared with healthy volunteers; consequently, 240 and 280 mg/m² doses were also tested to match healthy volunteer exposures. Based on PK and relevant safety data, 240 mg/m² was selected as the RP2D, which was also favored by myelopreservation endpoints in G1T28-02/-03.

Conclusion

Integrated PK/PD, safety, and efficacy data support 240 mg/m² as the RP2D for trilaciclib.

ClinicalTrials.gov Identifiers

NCT02243150; NCT02499770; NCT02514447.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00280-021-04239-9.

Cancer Patients' Perspectives and Experiences of Chemotherapy-Induced Myelosuppression and Its Impact on Daily Life

PURPOSE

To evaluate which side effects of chemotherapy are considered most burdensome by patients with cancer, identify which health care professionals pay most attention to symptoms associated with chemotherapy-induced myelosuppression (CIM) from the patient perspective, and capture the "patient voice" describing how CIM impacts their daily lives.

PARTICIPANTS AND METHODS

Online survey of participants with breast, lung, or colorectal cancer who had received chemotherapy within the past 12 months and experienced ≥1 episode of CIM in the past year. Participants were asked to answer close-ended questions and provide qualitative responses to: "In your own words, please describe how side effects from myelosuppression have impacted your life."

RESULTS

Among 301 survey participants, fatigue was the most frequently reported side effect of chemotherapy; 55% of participants rated fatigue as highly bothersome (9 or 10 on a 1-10 scale of "bothersomeness"). Participants rated symptoms associated with CIM, including fatigue, weakened immune system (infections), bleeding and/or bruising, and shortness of breath, as being as bothersome as other side effects of chemotherapy, including alopecia, neuropathy, and nausea/vomiting. Overall, 24-43% of participants thought that CIM and its symptoms had a negative impact on their daily lives, including their ability to complete tasks at home and work, and to socialize. Qualitative responses supported these findings; participants highlighted that CIM-related symptoms, particularly fatigue and fear of infections, affected their ability to be physically active, complete work, or continue meaningful relationships with friends and family.

CONCLUSION

Participants described a real-world impact of CIM that often isolates them from family and friends, and means that they are unable to work or perform tasks of daily living. Using measures that help patients to recognize and communicate the signs and symptoms of CIM might increase the likelihood of maintaining daily lives as close to normal as possible, during and after chemotherapy treatment.

Myelopreservation with Trilaciclib in Patients Receiving Topotecan for Small Cell Lung Cancer: Results from a Randomized, Double-Blind, Placebo-Controlled Phase II Study

INTRODUCTION

Multilineage myelosuppression is an acute toxicity of cytotoxic chemotherapy, resulting in serious complications and dose modifications. Current therapies are lineage specific and administered after chemotherapy damage has occurred. Trilaciclib is a cyclin-dependent kinase 4/6 inhibitor that is administered prior to chemotherapy to preserve hematopoietic stem and progenitor cells and immune system function during chemotherapy (myelopreservation).

METHODS

In this randomized, double-blind, placebo-controlled phase II trial, patients with previously treated extensive-stage small cell lung cancer (ES-SCLC) were randomized to receive intravenous trilaciclib 240 mg/m2 or placebo before topotecan 1.5 mg/m2 on days 1-5 of each 21-day cycle. Primary endpoints were duration of severe neutropenia (DSN) in cycle 1 and occurrence of severe neutropenia (SN). Additional endpoints were prespecified to further assess the effect of trilaciclib on myelopreservation, safety, patient-reported outcomes (PROs), and antitumor efficacy.

RESULTS

Thirty-two patients received trilaciclib, and 29 patients received placebo. Compared with placebo, administration of trilaciclib prior to topotecan resulted in statistically significant and clinically meaningful decreases in DSN in cycle 1 (mean [standard deviation] 2 [3.9] versus 7 [6.2] days; adjusted one-sided P < 0.0001) and occurrence of SN (40.6% versus 75.9%; adjusted one-sided P = 0.016), with numerical improvements in additional neutrophil, red blood cell, and platelet measures. Patients receiving trilaciclib had fewer grade ≥ 3 hematologic adverse events than patients receiving placebo, particularly neutropenia (75.0% versus 85.7%) and anemia (28.1% versus 60.7%). Myelopreservation benefits extended to improvements in PROs, specifically in those related to fatigue. Antitumor efficacy was comparable between treatment arms.

CONCLUSIONS

Compared with placebo, the addition of trilaciclib prior to topotecan for the treatment of patients with previously treated ES-SCLC improves the patient experience of receiving chemotherapy, as demonstrated by a reduction in chemotherapy-induced myelosuppression, improved safety profile, improved quality of life and no detrimental effects on antitumor efficacy.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02514447.

Risk of bleeding during oral surgery in patients with liver cirrhosis: A systematic review

BACKGROUND

The liver is responsible for the production of almost all coagulation factors, but does this indicate a risk of developing unusual bleeding in patients with liver cirrhosis during dental surgery?

TYPES OF STUDIES REVIEWED

In this systemic review, the authors followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist and performed a search of PubMed, Latin American and Caribbean Health Sciences Literature, Web of Science, Scopus, and Cochrane databases.

RESULTS

Seven studies met the inclusion criteria. The sample sizes ranged from 23 through 318 participants, number of extracted teeth ranged from 62 through 1,183, platelet count ranged from 16,000 through 216,000 per cubic milimeter, and the international normalized ratio was less than 4. The prevalence of hemorrhagic events in the studies ranged from 0% through 8.9%, and almost all were controlled with local hemostatic measures.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

During dental treatment, patients with liver cirrhosis have a low bleeding risk in spite of the decreased number of platelets and increased international normalized ratio.

Review article: a treatment algorithm for patients with chronic liver disease and severe thrombocytopenia undergoing elective medical procedures in the United States

BACKGROUND

Thrombocytopenia is the most common haematological abnormality in patients with chronic liver disease in the United States. Severe thrombocytopenia (platelet count <50 × 10⁹ /L) can complicate the management of patients with chronic liver disease by significantly increasing the potential risk of bleeding during or after invasive procedures. The current standard-of-care treatment for severe thrombocytopenia is platelet transfusion. Novel agents that target the thrombopoietin pathway, including receptor agonists avatrombopag and lusutrombopag, have recently shown promise in clinical trials as alternatives to platelet transfusion.

AIM

To review treatment options for severe thrombocytopenia, including platelet transfusion and thrombopoietin-receptor agonists, with the aim of producing a simplified treatment algorithm.

METHODS

Five liver disease specialists were assigned sections of the manuscript to research and present at a consensus meeting in April 2019, with the goal of creating an easy-to-use, effective treatment plan for severe thrombocytopenia in patients with chronic liver disease.

RESULTS

Through discussion and collaborative decision making, a simplified algorithm was developed to provide guidance to healthcare professionals on treating severe thrombocytopenia in patients with chronic liver disease undergoing elective medical procedures in the United States. As part of these guidelines, we outline the use of the US Food and Drug Administration-approved thrombopoietin receptor agonists avatrombopag and lusutrombopag as well tolerated and effective alternatives to platelet transfusion.

CONCLUSIONS

This algorithm provides guidance for the management of severe thrombocytopenia to reduce bleeding risks in patients with chronic liver disease undergoing elective procedures, while reducing requirement for platelet transfusion.

Lusutrombopag Is Safe and Efficacious for Treatment of Thrombocytopenia in Patients With and Without Hepatocellular Carcinoma

BACKGROUND & AIMS

Patients with hepatocellular carcinoma (HCC) secondary to chronic liver disease often require invasive procedures but frequently have thrombocytopenia. Lusutrombopag is an agonist of the thrombopoietin receptor that activates platelet production.

METHODS

We performed an integrated analysis of data from 2 phase 3 trials (L-PLUS 1, Japan, October 2013 to May 2014, and L-PLUS 2, global, June 2015 to April 2017) that compared the efficacy and safety of lusutrombopag with placebo in patients with chronic liver disease, with and without HCC. Our analysis included patients with Eastern Cooperative Oncology Group grades of 0 or 1, Child-Pugh classes A or B, and a platelet count less than 50 × 10⁹/L who were scheduled to undergo invasive procedures in 9 to 14 days. Patients received lusutrombopag (3 mg) or placebo daily for 7 days or fewer before an invasive procedure. Imaging studies assessed treatment-emergent adverse events, including asymptomatic portal vein thrombosis. The primary end point was no requirement for platelet transfusion before the invasive procedure and rescue therapies for bleeding 7 days or fewer after the invasive procedure.

RESULTS

The per-protocol population included 270 patients (95 with HCC). A significantly higher proportion of patients with HCC who received lusutrombopag achieved the primary end point (68.0%) vs patients who received placebo (8.9%) (P < .0001); in patients without HCC, these proportions were 77.0% vs 21.6% (P < .0001). Lusutrombopag reduced the need for platelet transfusions, increased platelet counts for 3 weeks, and reduced the number of bleeding events in patients with and without HCC compared with placebo. Risk of thrombosis was similar to that of placebo.

CONCLUSIONS

Patients with and without HCC receiving lusutrombopag had a reduction in the number of platelet transfusions before invasive procedures compared with patients receiving placebo, with no increase in thrombosis or bleeding. L-PLUS 1: JapicCTI-132323; L-PLUS 2: ClinicalTrials.gov number no: NCT02389621.

Modulation of Platelet-Surface Activation: Current State and Future Perspectives

Modulation of platelet-surface activation is important for many biomedical applications such as in vivo performance, platelet storage, and acceptance of an implant. Reducing platelet-surface activation is challenging because they become activated immediately after short contact with nonphysiological surfaces. To date, controversies and open questions in the field of platelet-surface activation still remain. Here, we review state-of-the-art approaches in inhibiting platelet-surface activation, mainly focusing on modification, patterning, and methodologies for characterization of the surfaces. As a future perspective, we discuss how the combination of biochemical and physiochemical strategies together with the topographical modulations would assist in the search for an ideal nonthrombogenic surface.

A pre-operative platelet transfusion algorithm for patients with cirrhosis and hepatocellular carcinoma undergoing laparoscopic microwave ablation

BACKGROUND

Thrombocytopenia is a common finding in patients with chronic liver disease. It is associated with poor clinical outcomes due to increased risk of bleeding after even minor procedures. We sought to determine an algorithm for pre-operative platelet transfusion in patients with cirrhosis and hepatocellular carcinoma (HCC) undergoing laparoscopic microwave ablation (MIS-MWA).

METHODS

A retrospective review identified all patients with cirrhosis and HCC who underwent MIS-MWA at a single tertiary institution between 2007 and 2019. Demographics, pre-operative and post-operative laboratory values, transfusion requirements, and bleeding events were collected. The analyzed outcome of bleeding risk included any transfusion received intra-operatively or a transfusion or surgical intervention post-operatively. Logistic regression models were created to predict bleeding risk and identify patients who would benefit from pre-operative transfusion.

RESULTS

There were 433 patients with cirrhosis and HCC who underwent MIS-MWA identified; of these, 353 patients had complete laboratory values and were included. Bleeding risk was evaluated through bivariate analysis of statistically and clinically significant variables. The accuracy of both models was substantiated through bootstrap validation for 500 iterations (model 1: ROC 0.8684, Brier score 0.0238; model 2: ROC 0.8363, Brier score 0.0252). The first model captured patients with both thrombocytopenia and anemia: platelet count < 60 × 10⁹ / L (OR 7.75, p 0.012, CI 1.58-38.06) and hemoglobin < 10 gm/dL (OR 5.76, p 0.032, CI 1.16-28.63). The second model captured patients with thrombocytopenia without anemia: platelet count < 30 × 10⁹/L (OR 8.41, p 0.05, CI 0.96-73.50) and hemoglobin > 10 gm/dL (OR 0.16, p 0.026, CI 0.031-0.80).

CONCLUSION

The prediction of patients with cirrhosis and HCC requiring pre-operative platelet transfusions may help to avoid bleeding complications after invasive procedures. This study needs to be prospectively validated and ultimately may be beneficial in assessment of novel therapies for platelet-based clinical treatment in liver disease.

Establishment of the first platelet-donor registry in Argentina

BACKGROUND

Platelet transfusions are necessary to prevent and treat haemorrhages in thrombocytopenic patients or those with severe platelet dysfunction. In Latin American countries, including Argentina, blood supplies from voluntary non-remunerated blood donors remain dependent on family replacement donors, since altruistic repeat donors are exceptional and platelet donors are very scarce. The aim of this study was to recruit a group of frequent, voluntary, altruistic blood donors and determine their human platelet antigen (HPA)-genotype in order to establish the first registry of HPA-typed voluntary platelet donors in Argentina.

MATERIAL AND METHODS

In this study, we invited and recruited voluntary blood donors who attended the Fundación Banco Central de Sangre between July 2016 and July 2017. DNA was extracted from K2EDTA anticoagulated whole blood and genotyping was performed by polymerase chain reaction, using sequence-specific primers to type the HPA-1 to -6, -9 and -15 systems. A subset of samples was also tested using a commercial HPA-TYPE kit. Donors were invited to join the National Register of Haematopoietic Stem Cell Donors of Argentina.

RESULTS

A cohort of 500 platelet donors was recruited and characterised and a database with their personal information, including their genotype for the most relevant HPA alloantigens, was created. Eight of the 500 donors (1.6%) were HPA-1a negative. HPA allelic variants -4b, -6b and -9b were detected for the first time in our population. There was 100% concordance between our in-house assay and the commercial kits in the subset of 150 donor samples assayed in parallel.

DISCUSSION

The efforts made to recruit, characterise and register voluntary platelet donors will provide the first sustainable source of HPA and human leukocyte antigen-typed platelets for compatible transfusions in the country. Remarkably, we identified a higher percentage of HPA-1a-negative donors than previously detected in the Argentinean population.

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.

Avatrombopag, an Alternate Treatment Option to Reduce Platelet Transfusions in Patients with Thrombocytopenia and Chronic Liver Disease-Integrated Analyses of 2 Phase 3 Studies

AIMS

Thrombocytopenia complicates the management of patients with chronic liver disease (CLD) undergoing invasive procedures with a bleeding risk. Until recently, prophylactic platelet transfusion was the only treatment option, but has significant safety and efficacy limitations. Phase 3 data demonstrated the superiority of avatrombopag to placebo in reducing platelet transfusions for bleeding, supporting its recent approval.

METHODS

Integrated analyses of pooled data (N = 435) from two randomized, double-blind, placebo-controlled, phase 3 studies assessed the original efficacy endpoints. Additional analyses included subgroup analyses, alternate Baseline platelet count definitions, and another efficacy endpoint.

RESULTS

Avatrombopag was superior to placebo in increasing patients not requiring a platelet transfusion or rescue procedure, those achieving a platelet count ≥50 × 10⁹/L on Procedure Day, and the change in platelet counts from Baseline. The avatrombopag treatment effect was consistently positive across clinically important disease and Baseline clinical characteristic subgroups, and using alternate Baseline platelet count cohort definitions. Similarly, more avatrombopag-treated patients achieved ≥50 × 10⁹/L platelets with an increase of ≥20 × 10⁹/L from Baseline. The incidence and severity of adverse events were similar between avatrombopag and placebo. Further, safety data demonstrated a low risk for thromboembolic events and hepatotoxicity.

CONCLUSION

These integrated analyses confirmed the superiority of avatrombopag to placebo in reducing platelet transfusions or rescue procedures for bleeding in patients with thrombocytopenia and CLD scheduled to undergo an invasive procedure, and its tolerable safety profile. Importantly, these data warrant reconsideration of clinical decision making regarding the need to treat thrombocytopenia in patients with CLD. This trial was registered with NCT01972529 and NCT01976104.

Mechanisms and therapeutic prospects of thrombopoietin receptor agonists

The second-generation thrombopoietin (TPO) receptor agonists eltrombopag and romiplostim are potent activators of megakaryopoiesis and represent a growing treatment option for patients with thrombocytopenic hematological disorders. Both TPO receptor agonists have been approved worldwide for the treatment of children and adults with chronic immune thrombocytopenia. In the EU and USA, eltrombopag is approved for the treatment of patients with severe aplastic anemia who have had an insufficient response to immunosuppressive therapy and in the USA for the first-line treatment of severe aplastic anemia in combination with immunosuppressive therapy. Eltrombopag has also shown efficacy in several other disease settings, for example, chemotherapy-induced thrombocytopenia, selected inherited thrombocytopenias, and myelodysplastic syndromes. While both TPO receptor agonists stimulate TPO receptor signaling and enhance megakaryopoiesis, their vastly different biochemical structures bestow upon them markedly different molecular and functional properties. Here, we review and discuss results from preclinical and clinical studies on the functional and molecular mechanisms of action of this new class of drug.

Lusutrombopag for the Treatment of Thrombocytopenia in Patients With Chronic Liver Disease Undergoing Invasive Procedures (L-PLUS 2)

Thrombocytopenia may be associated with increased bleeding risk impacting timing and outcome of invasive procedures in patients with chronic liver disease (CLD). Lusutrombopag, a small-molecule, thrombopoietin (TPO) receptor agonist, was evaluated as a treatment to raise platelet counts (PCs) in patients with thrombocytopenia and CLD undergoing invasive procedures. L-PLUS 2 was a global, phase 3, randomized, double-blind, placebo-controlled study. Adults with CLD and baseline PCs < 50 × 10⁹ /L were randomized to receive once-daily lusutrombopag 3 mg or placebo ≤ 7 days before an invasive procedure scheduled 2-7 days after the last dose. The primary endpoint was avoidance of preprocedure platelet transfusion and avoidance of rescue therapy for bleeding. A key secondary endpoint was number of days PCs were ≥ 50 × 10⁹ /L throughout the study. Safety analysis was performed on patients who received at least one dose of study drug. This study occurred between June 15, 2015, and April 19, 2017, with a total of 215 randomized patients (lusutrombopag, 108; placebo, 107); 64.8% (70/108) of patients in the lusutrombopag group versus 29.0% (31/107) in the placebo group met the primary endpoint (P < 0.0001; difference of proportion 95% confidence interval [CI], 36.7 [24.9, 48.5]). The median duration of PCs ≥ 50 × 10⁹ /L was 19.2 days with lusutrombopag (without platelet transfusion) compared with 0.0 in the placebo group (with platelet transfusion) (P = 0.0001). Most adverse events were mild or moderate in severity, and rates were similar in the lusutrombopag and placebo groups (47.7% and 48.6%, respectively). Conclusion: Lusutrombopag was superior to placebo for reducing the need for platelet transfusions and achieved durable PC response in patients with thrombocytopenia and CLD undergoing invasive procedures, with a safety profile similar to placebo.

Management of Thrombocytopenia in Patients with Chronic Liver Disease

BACKGROUND

Thrombocytopenia is the most common hematologic complication associated with chronic liver disease (CLD) with important clinical implications. While the mechanisms for thrombocytopenia are multifactorial, platelet sequestration in the spleen and decreased thrombopoietin (TPO) production are the main mechanisms in patients with CLD.

AIM

This review outlines the current treatment options for thrombocytopenia in patients with CLD, explores their limitations, and proposes a revised treatment algorithm for the management of thrombocytopenia in this patient group.

METHODS

A PubMed search of the literature was undertaken with search terms focused on CLD and thrombocytopenia.

RESULTS

Until now, the standard-of-care treatment in these patients has been the use of platelet transfusions either prophylactically or periprocedurally to control bleeding. Treatment options, such as splenic artery embolization and splenectomy, are invasive, and their utility is limited by significant complications. The US Food and Drug Administration recently approved 2 s-generation TPO-receptor agonists, avatrombopag and lusutrombopag, as safe and effective therapies for the treatment of thrombocytopenia in patients with CLD scheduled to undergo a procedure.

CONCLUSIONS

The addition of avatrombopag and lusutrombopag offers physicians an alternative to platelet transfusions in patients with CLD who have to undergo medical/dental procedures that could potentially put them at an increased risk of bleeding. There are several other drugs in the research pipeline at various stages of development, including a new class of monoclonal antibodies that can bind to and activate TPO-receptor agonists. The outlook for treatment choices for thrombocytopenia in patients with liver disease is promising.

Predicting chemotherapy-induced thrombocytopenia in cancer patients with solid tumors or lymphoma

Purpose

Chemotherapy-induced thrombocytopenia is a serious complication in chemotherapy-treated patients. Identification of patients at risk for chemotherapy-induced thrombocytopenia could have clinical value in personalized management of patients and optimized administration of prophylactic thrombopoietic agents. The aim of this study was to develop a predictive model for chemotherapy-induced thrombocytopenia (platelet count < 100,000/µl) in cancer patients undergoing chemotherapy.

Methods

A total of 14 covariates were prospectively assessed as explanatory variables in a cohort of consecutive patients with solid tumors or lymphoma. A multivariable logistic regression model was developed after univariable analysis. A bootstrapping technique was applied for internal validation.

Results

Data from 305 patients during 1732 chemotherapy cycles were considered for analysis. Forty-eight patients (15.73%) developed chemotherapy-induced thrombocytopenia during their treatment course. The multivariable model exhibited three final predictors for chemotherapy-induced thrombocytopenia, including high ferritin (odds ratio, 4.41; bootstrap P = 0.001), estimated glomerular filtration rate <60 ml/min/1.73 m2(odds ratio, 3.08; bootstrap P = 0.005), and body mass index <23 kg/m2(odds ratio, 2.23; bootstrap P = 0.044). The main characteristics of the model include sensitivity 75%, specificity 65.4%, positive likelihood ratio 2.16, and negative likelihood ratio 0.382. Moreover, the model was well calibrated (Hosmer–Lemeshow P = 0.713) and the area under the receiver operating characteristic curve was 0.735 (95% confidence interval, 0.654–0.816; P < 0.001).

Conclusions

We developed a predictive model for chemotherapy-induced thrombocytopenia based on readily available and easily assessable clinical and laboratory factors. This study may provide a valuable insight to guide optimized treatment of cancer patients. Further studies with larger sample size are warranted.

Lusutrombopag Reduces Need for Platelet Transfusion in Patients With Thrombocytopenia Undergoing Invasive Procedures

BACKGROUND & AIMS

Platelet transfusion is used to prevent hemorrhagic events in patients with thrombocytopenia undergoing invasive procedures, but there are many disadvantages. We evaluated the efficacy and safety of lusutrombopag in patients with chronic liver disease and thrombocytopenia undergoing invasive procedures.

METHODS

We performed a double-blind, parallel-group, phase 3 study of 96 patients with chronic liver disease and thrombocytopenia (platelet counts below 50,000/μL) undergoing invasive procedures from October 2013 to May 2014 at 81 centers in Japan. Patients were randomly assigned (1:1) to groups given once-daily lusutrombopag (3 mg) or placebo for up to 7 days. The primary efficacy endpoint was the proportion of patients not requiring platelet transfusion before the invasive procedure. The protocol-defined response (platelet count 50,000/μL or more with an increase of 20,000/μL or more from baseline) and the time course of the change in platelet count were also evaluated. Adverse events were recorded.

RESULTS

The proportions of patients who did not require preoperative platelet transfusion were 79.2% (38/48) in the lusutrombopag group and 12.5% (6/48) in the placebo group (P < .0001). A response was observed in 77.1% (37/48) of patients in the lusutrombopag group and 6.3% (3/48) of patients in the placebo group (P < .0001). In the lusutrombopag group without platelet transfusion, the median platelet count was 50,000/μL or more after 5 days; the mean time to reach the maximum platelet count was 13.4 days; and the number of days (adjusted mean) during which the platelet count was 50,000/μL or more was 21.09 days. Adverse drug reactions were reported in 8.3% of patients in the lusutrombopag group and 2.1% of patients in the placebo group. Two patients (1 per group) had a thrombotic event, but neither were associated with an excessive increase in platelet count (200,000/μL or more).

CONCLUSION

In a placebo-controlled trial, lusutrombopag was effective in achieving and maintaining the target platelet count in patients with chronic liver disease and thrombocytopenia undergoing invasive procedures. No significant safety concerns were raised. Japanese clinical trial registration no: JapicCTI-132323.

Mitochondrial neurogastrointestinal encephalomyopathy: approaches to diagnosis and treatment

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an ultra-rare disease caused by mutations in TYMP, the gene encoding for the enzyme thymidine phosphorylase. The resulting enzyme deficiency leads to a systemic accumulation of thymidine and 2’-deoxyuridine and ultimately mitochondrial failure due to a progressive acquisition of secondary mitochondrial DNA (mtDNA) mutations and mtDNA depletion. MNGIE is characterised by gastrointestinal dysmotility, cachexia, peripheral neuropathy, ophthalmoplegia, ptosis and leukoencephalopathy. The disease is progressively degenerative and leads to death at an average age of 37.6 years. Patients invariably encounter misdiagnoses, diagnostic delays, and non-specific clinical management. Despite its rarity, MNGIE has invoked much interest in the development of therapeutic strategies, mainly because it is one of the few mitochondrial disorders where the molecular abnormality is metabolically and physically accessible to manipulation. This review provides a resume of the current diagnosis and treatment approaches and aims to increase the clinical awareness of MNGIE and thereby facilitate early diagnosis and timely access to treatments, before the development of untreatable and irreversible organ damage.

Blood loss mitigation and replacement in facial surgery: a review

PURPOSE OF REVIEW

To provide a comprehensive overview of the predisposing factors that contribute to a risk of excess bleeding for surgical therapy in the head and neck regions, provide a thorough overview of techniques and tools for managing blood loss complications, and provide intervention algorithms to help guide clinical decision making.

RECENT FINDINGS

With the current landscape of medications and reversal agents, protocols for intervention in a variety of situations, and new tools for blood loss management all rapidly changing and being developed it is critical to stay up to date to provide patients the best care in the most critical of situations.

SUMMARY

With the risk of blood loss complications in head and neck surgery ranging from minimal to extreme surgeons require a comprehensive understanding risk factors, patient evaluation tools, and proper management algorithms. The first opportunity to prevent unnecessary blood loss and blood loss complications is the health history and physical appointment where a clinician can identify any medications, conditions, or other predisposing factors that would elevate a patient's risk of excess bleeding and the necessity for treatment augmentation. Although not all complications can be prevented because of the natural physiological variation that occurs from patient to patient, despite proper and proper diagnostics, a full working knowledge of most likely complications, hemostatic tools, and concise communication with team members can prevent a lot of blood loss and the complications associated.

Prophylactic platelet transfusions prior to surgery for people with a low platelet count

BACKGROUND

People with thrombocytopenia often require a surgical procedure. A low platelet count is a relative contraindication to surgery due to the risk of bleeding. Platelet transfusions are used in clinical practice to prevent and treat bleeding in people with thrombocytopenia. Current practice in many countries is to correct thrombocytopenia with platelet transfusions prior to surgery. Alternatives to platelet transfusion are also used prior surgery.

OBJECTIVES

To determine the clinical effectiveness and safety of prophylactic platelet transfusions prior to surgery for people with a low platelet count.

SEARCH METHODS

We searched the following major data bases: Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), PubMed (e-publications only), Ovid MEDLINE, Ovid Embase, the Transfusion Evidence Library and ongoing trial databases to 11 December 2017.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs), as well as non-RCTs and controlled before-and-after studies (CBAs), that met Cochrane EPOC (Effective Practice and Organisation of Care) criteria, that involved the transfusion of platelets prior to surgery (any dose, at any time, single or multiple) in people with low platelet counts. We excluded studies on people with a low platelet count who were actively bleeding.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane for data collection. We were only able to combine data for two outcomes and we presented the rest of the findings in a narrative form.

MAIN RESULTS

We identified five RCTs, all conducted in adults; there were no eligible non-randomised studies. Three completed trials enrolled 180 adults and two ongoing trials aim to include 627 participants. The completed trials were conducted between 2005 and 2009. The two ongoing trials are scheduled to complete recruitment by October 2019. One trial compared prophylactic platelet transfusions to no transfusion in people with thrombocytopenia in an intensive care unit (ICU). Two small trials, 108 participants, compared prophylactic platelet transfusions to other alternative treatments in people with liver disease. One trial compared desmopressin to fresh frozen plasma or one unit of platelet transfusion or both prior to surgery. The second trial compared platelet transfusion prior to surgery with two types of thrombopoietin mimetics: romiplostim and eltrombopag. None of the included trials were free from methodological bias. No included trials compared different platelet count thresholds for administering a prophylactic platelet transfusion prior to surgery. None of the included trials reported on all the review outcomes and the overall quality per reported outcome was very low.None of the three completed trials reported: all-cause mortality at 90 days post surgery; mortality secondary to bleeding, thromboembolism or infection; number of red cell or platelet transfusions per participant; length of hospital stay; or quality of life.None of the trials included children or people who needed major surgery or emergency surgical procedures.Platelet transfusion versus no platelet transfusion (1 trial, 72 participants)We were very uncertain whether giving a platelet transfusion prior to surgery had any effect on all-cause mortality within 30 days (1 trial, 72 participants; risk ratio (RR) 0.78, 95% confidence interval (CI) 0.41 to 1.45; very-low quality evidence). We were very uncertain whether giving a platelet transfusion prior to surgery had any effect on the risk of major (1 trial, 64 participants; RR 1.60, 95% CI 0.29 to 8.92; very low-quality evidence), or minor bleeding (1 trial, 64 participants; RR 1.29, 95% CI 0.90 to 1.85; very-low quality evidence). No serious adverse events occurred in either study arm (1 trial, 72 participants, very low-quality evidence).Platelet transfusion versus alternative to platelet transfusion (2 trials, 108 participants)We were very uncertain whether giving a platelet transfusion prior to surgery compared to an alternative has any effect on the risk of major (2 trials, 108 participants; no events; very low-quality evidence), or minor bleeding (desmopressin: 1 trial, 36 participants; RR 0.89, 95% CI 0.06 to 13.23; very-low quality evidence: thrombopoietin mimetics: 1 trial, 65 participants; no events; very-low quality evidence). We were very uncertain whether there was a difference in transfusion-related adverse effects between the platelet transfused group and the alternative treatment group (desmopressin: 1 trial, 36 participants; RR 2.70, 95% CI 0.12 to 62.17; very-low quality evidence).

AUTHORS' CONCLUSIONS

Findings of this review were based on three small trials involving minor surgery in adults with thrombocytopenia. We found insufficient evidence to recommend the administration of preprocedure prophylactic platelet transfusions in this situation with a lack of evidence that transfusion resulted in a reduction in postoperative bleeding or all-cause mortality. The small number of trials meeting the inclusion criteria and the limitation in reported outcomes across the trials precluded meta-analysis for most outcomes. Further adequately powered trials, in people of all ages, of prophylactic platelet transfusions compared with no transfusion, other alternative treatments, and considering different platelet thresholds prior to planned and emergency surgical procedures are required. Future trials should include major surgery and report on bleeding, adverse effects, mortality (as a long-term outcome) after surgery, duration of hospital stay and quality of life measures.

Comparison of a therapeutic-only versus prophylactic platelet transfusion policy for people with congenital or acquired bone marrow failure disorders

BACKGROUND

Bone marrow disorders encompass a group of diseases characterised by reduced production of red cells, white cells, and platelets, or defects in their function, or both. The most common bone marrow disorder is myelodysplastic syndrome. Thrombocytopenia, a low platelet count, commonly occurs in people with bone marrow failure. Platetet transfusions are routinely used in people with thrombocytopenia secondary to bone marrow failure disorders to treat or prevent bleeding. Myelodysplastic syndrome is currently the most common reason for receiving a platelet transfusion in some Western countries.

OBJECTIVES

To determine whether a therapeutic-only platelet transfusion policy (transfusion given when patient is bleeding) is as effective and safe as a prophylactic platelet transfusion policy (transfusion given to prevent bleeding according to a prespecified platelet threshold) in people with congenital or acquired bone marrow failure disorders.

SEARCH METHODS

We searched for randomised controlled trials (RCTs), non-RCTs, and controlled before-after studies (CBAs) in the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2017, Issue 9), Ovid MEDLINE (from 1946), Ovid Embase (from 1974), PubMed (e-publications only), the Transfusion Evidence Library (from 1950), and ongoing trial databases to 12 October 2017.

SELECTION CRITERIA

We included RCTs, non-RCTs, and CBAs that involved the transfusion of platelet concentrates (prepared either from individual units of whole blood or by apheresis any dose, frequency, or transfusion trigger) and given to treat or prevent bleeding among people with congenital or acquired bone marrow failure disorders.We excluded uncontrolled studies, cross-sectional studies, and case-control studies. We excluded cluster-RCTs, non-randomised cluster trials, and CBAs with fewer than two intervention sites and two control sites due to the risk of confounding. We included all people with long-term bone marrow failure disorders that require platelet transfusions, including neonates. We excluded studies of alternatives to platelet transfusion, or studies of people receiving intensive chemotherapy or a stem cell transplant.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures outlined by Cochrane. Due to the absence of evidence we were unable to report on any of the review outcomes.

MAIN RESULTS

We identified one RCT that met the inclusion criteria for this review. The study enrolled only nine adults with MDS over a three-year study duration period. The trial was terminated due to poor recruitment rate (planned recruitment 60 participants over two years). Assessment of the risk of bias was not possible for all domains. The trial was a single-centre, single-blind trial. The clinical and demographic characteristics of the participants were never disclosed. The trial outcomes relevant to this review were bleeding assessments, mortality, quality of life, and length of hospital stay, but no data were available to report on any of these outcomes.We identified no completed non-RCTs or CBAs.We identified no ongoing RCTs, non-RCTs, or CBAs.

AUTHORS' CONCLUSIONS

We found no evidence to determine the safety and efficacy of therapeutic platelet transfusion compared with prophylactic platelet transfusion for people with long-term bone marrow failure disorders. This review underscores the urgency of prioritising research in this area. People with bone marrow failure depend on long-term platelet transfusion support, but the only trial that assessed a therapeutic strategy was halted. There is a need for good-quality studies comparing a therapeutic platelet transfusion strategy with a prophylactic platelet transfusion strategy; such trials should include outcomes that are important to patients, such as quality of life, length of hospital admission, and risk of bleeding.

Use of platelet transfusions prior to lumbar punctures or epidural anaesthesia for the prevention of complications in people with thrombocytopenia

BACKGROUND

People with a low platelet count (thrombocytopenia) often require lumbar punctures or an epidural anaesthetic. Lumbar punctures can be diagnostic (haematological malignancies, subarachnoid haematoma, meningitis) or therapeutic (spinal anaesthetic, administration of chemotherapy). Epidural catheters are placed for administration of epidural anaesthetic. Current practice in many countries is to correct thrombocytopenia with platelet transfusions prior to lumbar punctures and epidural anaesthesia, in order to mitigate the risk of serious procedure-related bleeding. However, the platelet count threshold recommended prior to these procedures varies significantly from country to country. This indicates significant uncertainty among clinicians regarding the correct management of these patients. The risk of bleeding appears to be low, but if bleeding occurs it can be very serious (spinal haematoma). Consequently, people may be exposed to the risks of a platelet transfusion without any obvious clinical benefit.This is an update of a Cochrane Review first published in 2016.

OBJECTIVES

To assess the effects of different platelet transfusion thresholds prior to a lumbar puncture or epidural anaesthesia in people with thrombocytopenia (low platelet count).

SEARCH METHODS

We searched for randomised controlled trials (RCTs), non-randomised controlled trials (nRCTs), controlled before-after studies (CBAs), interrupted time series studies (ITSs), and cohort studies in CENTRAL (the Cochrane Library 2018, Issue 1), MEDLINE (from 1946), Embase (from 1974), the Transfusion Evidence Library (from 1950), and ongoing trial databases to 13 February 2018.

SELECTION CRITERIA

We included RCTs, nRCTs, CBAs, ITSs, and cohort studies involving transfusions of platelet concentrates, prepared either from individual units of whole blood or by apheresis, and given to prevent bleeding in people of any age with thrombocytopenia requiring insertion of a lumbar puncture needle or epidural catheter.The original review only included RCTs.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane for including RCTs, nRCTs, CBAs, and ITSs. Two review authors independently assessed studies for eligibility and risk of bias and extracted data. Results were only expressed narratively.

MAIN RESULTS

We identified no completed or ongoing RCTs, nRCTs, CBAs, or ITSs. No studies included people undergoing an epidural procedure. No studies compared different platelet count thresholds prior to a procedure.In this update we identified three retrospective cohort studies that contained participants who did and did not receive platelet transfusions prior to lumbar puncture procedures. All three studies were carried out in people with cancer, most of whom had a haematological malignancy. Two studies were in children, and one was in adults.The number of participants receiving platelet transfusions prior to the lumbar puncture procedures was not reported in one study. We therefore only summarised in a narrative form the relevant outcomes from two studies (150 participants; 129 children and 21 adults), in which the number of participants who received the transfusion was given.We judged the overall risk of bias for all reported outcomes for both studies as 'serious' based on the ROBINS-I tool.No procedure-related major bleeding occurred in the two studies that reported this outcome (2 studies, 150 participants, no cases, very low-quality evidence).There was no evidence of a difference in the risk of minor bleeding (traumatic tap) in participants who received platelet transfusions before a lumbar puncture and those who did not receive a platelet transfusion before the procedure (2 studies, 150 participants, very low-quality evidence). One of the 14 adults who received a platelet transfusion experienced minor bleeding (traumatic tap; defined as at least 500 x 10⁶/L red blood cells in the cerebrospinal fluid); none of the seven adults who did not receive a platelet transfusion experienced this event. Ten children experienced minor bleeding (traumatic taps; defined as at least 100 x 10⁶/L red blood cells in the cerebrospinal fluid), six out of the 57 children who received a platelet transfusion and four out of the 72 children who did not receive a platelet transfusion.No serious adverse events occurred in the one study that reported this outcome (1 study, 21 participants, very low-quality evidence).We found no studies that evaluated all-cause mortality within 30 days from the lumbar puncture procedure, length of hospital stay, proportion of participants who received platelet transfusions, or quality of life.

AUTHORS' CONCLUSIONS

We found no evidence from RCTs or non-randomised studies on which to base an assessment of the correct platelet transfusion threshold prior to insertion of a lumbar puncture needle or epidural catheter. There are no ongoing registered RCTs assessing the effects of different platelet transfusion thresholds prior to the insertion of a lumbar puncture or epidural anaesthesia in people with thrombocytopenia. Any future study would need to be very large to detect a difference in the risk of bleeding. A study would need to be designed with at least 47,030 participants to be able to detect an increase in the number of people who had major procedure-related bleeding from 1 in 1000 to 2 in 1000. The use of a central data collection register or routinely collected electronic records (big data) is likely to be the only method to systematically gather data relevant to this population.

Efficacy of platelet transfusion for acute intracerebral hemorrhage among patients on antiplatelet therapy

Clinical question

In patients taking antiplatelet therapy, does a platelet transfusion after acute spontaneous primary intracerebral hemorrhage reduce the risk of death or dependence?

Article chosen

Baharoglu MI, Cordonnier C, Al-Shahi Salman R, et al. Platelet transfusion versus standard care after acute stroke due to spontaneous cerebral hemorrhage associated with antiplatelet therapy (PATCH): a randomized, open-label, phase 3 trial.Lancet2016;387(10038):2605-13.

Study objective

The primary objective of this study was to investigate whether a platelet transfusion with standard care, compared with standard care alone, reduced death or dependence after intracerebral hemorrhage associated with antiplatelet therapy use.

Prophylactic platelet transfusions prior to surgery for people with a low platelet count

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To determine the clinical effectiveness and safety of prophylactic platelet transfusions prior to surgery for people with a low platelet count or platelet dysfunction (inherited or acquired).

Thrombocytopenia in chronic liver disease

Thrombocytopenia is a common haematological disorder in patients with chronic liver disease. It is multifactorial and severity of liver disease is the most influential factor. As a result of the increased risk of bleeding, thrombocytopenia may impact upon medical procedures, such as surgery or liver biopsy. The pathophysiology of thrombocytopenia in chronic liver disease has long been associated with the hypothesis of hypersplenism, where portal hypertension causes pooling and sequestration of all corpuscular elements of the blood, predominantly thrombocytes, in the enlarged and congested spleen. Other mechanisms of importance include bone marrow suppression by toxic substances, such as alcohol or viral infection, and immunological removal of platelets from the circulation. However, insufficient platelet recovery after relief of portal hypertension by shunt procedures or minor and transient recovery after splenic artery embolization have caused many to question the importance and relative contribution of this mechanism to thrombocytopenia. The discovery of the cytokine thrombopoietin has led to the elucidation of a central mechanism. Thrombopoietin is predominantly produced by the liver and is reduced when liver cell mass is severely damaged. This leads to reduced thrombopoiesis in the bone marrow and consequently to thrombocytopenia in the peripheral blood of patients with advanced-stage liver disease. Restoration of adequate thrombopoietin production post-liver transplantation leads to prompt restoration of platelet production. A number of new treatments that substitute thrombopoietin activity are available or in development.

Is cold blood cardioplegia absolutely superior to cold crystalloid cardioplegia in aortic valve surgery?

BACKGROUND

Experimental evidence suggests that blood cardioplegia (BCP) may be superior to cold crystalloid cardioplegia (CCP) for myocardial protection. However, robust clinical data are lacking. We compared postoperative outcome of patients undergoing aortic valve replacement (AVR) using cold anterograde-retrograde intermittent BCP versus anterograde (CCP).

METHODS

Adult consecutive isolated AVR performed between April 2006 and February 2011 at the Royal Infirmary Hospital of Edinburgh were retrospectively analyzed. The use of anterograde CCP was compared with that of intermittent anterograde-retrograde cold BCP. End points were intra-operative mortality, 30-day hospital re-admission, need for RBC or platelet transfusion, mechanical ventilation time and renal failure.

RESULTS

Of total 774 cases analyzed, 592 cases of BCP and 182 cases of CCP were identified. Demographics did not differ between groups (mean age: 67±12 years in CCP and 69±12 years in BCP). Groups (BCP vs. CCP) were indistinguishable (P>0.05, not significant) based on: average aortic cross clamp time 77.01±14.47 vs. 75.78±18.78 minutes, cardiopulmonary bypass time 104.07±43.70 vs. 100.34±25.90 minutes, surgery time 190.53±61.80 vs. 204.04±51.09 minutes and postoperative total blood consumption 1.38±2.11 vs. 1.61±2.4 units. The percentage of patients who required platelets' transfusion was similar: 12.8% BCP and 18.7% CCP (Fisher's exact test, P=0.053). Prevalence of respiratory failure was lower in BCP than in CCP: 2.6% vs. 6.3% (P=0.028). Admission time (days) at ICU was 3.63± 21.90 in BCP and 3.07±8.04 in CCP (not significant). Intra-hospital mortality, 30-day hospital re-admission, renal failure, sepsis, wound healing and stroke did not differ between groups.

CONCLUSIONS

BCP was strictly not superior to CCP in every aspect. In particular it was definitely not superior in terms of postoperative ventricular function. Our results question the absolute superiority of BCP over CCP in terms of hard outcomes. Likelihood of serious complications should be considered to improve risk profile of patients before choosing a cardioplegic solution.