Platelet transfusion in adults: An update.

Many patients worldwide receive platelet components (PCs) through the transfusion of diverse types of blood components. PC transfusions are essential for the treatment of central thrombocytopenia of diverse causes, and such treatment is beneficial in patients at risk of severe bleeding. PC transfusions account for almost 10% of all the blood components supplied by blood services, but they are associated with about 3.25 times as many severe reactions (attributable to transfusion) than red blood cell transfusions after stringent in-process leukoreduction to less than 106 residual cells per blood component. PCs are not homogeneous, due to the considerable differences between donors. Furthermore, the modes of PC collection and preparation, the safety precautions taken to limit either the most common (allergic-type reactions and febrile non-hemolytic reactions) or the most severe (bacterial contamination, pulmonary lesions) adverse reactions, and storage and conservation methods can all result in so-called PC "storage lesions". Some storage lesions affect PC quality, with implications for patient outcome. Good transfusion practices should result in higher levels of platelet recovery and efficacy, and lower complication rates. These practices include a matching of tissue ABH antigens whenever possible, and of platelet HLA (and, to a lesser extent, HPA) antigens in immunization situations. This review provides an overview of all the available information relating to platelet transfusion, from donor and donation to bedside transfusion, and considers the impact of the measures applied to increase transfusion efficacy while improving safety and preventing transfusion inefficacy and refractoriness. It also considers alternatives to platelet component (PC) transfusion.

Intention to get vaccinations against COVID-19 in French healthcare workers during the first pandemic wave: a cross-sectional survey.

BACKGROUND: Healthcare workers (HCWs) are at the frontline of the COVID-19 pandemic and identified as a priority target group for COVID-19 vaccines. We aimed to determine COVID-19 vaccine acceptance rate in HCWs in France. METHODS: We conducted an anonymous survey from 26th March to 2nd July 2020. The primary endpoint was the intention to get vaccinated against COVID-19 if a vaccine was available. RESULTS: Two-thousand and forty-seven HCWs answered the survey; women accounted for 74% of respondents. Among respondents, 1.554 (76.9%, 95% confidence interval 75.1-78.9) would accept a COVID-19 vaccine. Older age, male gender, fear about COVID-19, individual perceived risk and flu vaccination during previous season were associated with hypothetical COVID-19 vaccine acceptance. Nurses and assistant nurses were less prone to accept vaccination against COVID-19 than physicians. Vaccine hesitancy was associated with a decrease in COVID-19 vaccine acceptance. Flu vaccine rate was 57.3% during the previous season, and 54.6% of the respondents had the intention to get a flu vaccine during the next season. CONCLUSIONS: Intention to get vaccinated against COVID-19 reached 75% in HCWs with discrepancies between occupational categories. COVID-19 pandemic had no positive effect on flu vaccine acceptance rate.

Nanofibrillar networks enable universal assembly of superstructured particle constructs.

Superstructured colloidal materials exploit the synergies between components to develop new or enhanced functions. Cohesion is a primary requirement for scaling up these assemblies into bulk materials, and it has only been fulfilled in case-specific bases. Here, we demonstrate that the topology of nanonetworks formed from cellulose nanofibrils (CNFs) enables robust superstructuring with virtually any particle. An intermixed network of fibrils with particles increases the toughness of the assemblies by up to three orders of magnitude compared, for instance, to sintering. Supramolecular cohesion is transferred from the fibrils to the constructs following a power law, with a constant decay factor for particle sizes from 230 nm to 40 µm. Our findings are applicable to other nanofiber dimensions via a rationalization of the morphological aspects of both particles and nanofibers. CNF-based cohesion will move developments of functional colloids from laboratory-scale toward their implementation in large-scale nanomanufacturing of bulk materials.

Bleeding risk of terminally ill patients hospitalized in palliative care units: the RHESO study.

Essentials Bleeding incidence as hemorrhagic risk factors are unknown in palliative care inpatients. We conducted a multicenter observational study (22 Palliative Care Units, 1199 patients). At three months, the cumulative incidence of clinically relevant bleeding was 9.8%. Cancer, recent bleeding, thromboprophylaxis and antiplatelet therapy were independent risk factors. SUMMARY: Background The value of primary thromboprophylaxis in patients admitted to palliative care units is debatable. Moreover, the risk of bleeding in these patients is unknown. Objectives Our primary aim was to assess the bleeding risk of patients in a real-world practice setting of hospital palliative care. Our secondary aim was to determine the incidence of symptomatic deep vein thrombosis and to identify risk factors for bleeding. Patients/Methods In this prospective, observational study in 22 French palliative care units, 1199 patients (median age, 71 years; male, 45.5%), admitted for the first time to a palliative care unit for advanced cancer or pulmonary, cardiac or neurologic disease were included. The primary outcome was adjudicated clinically relevant bleeding (i.e. a composite of major and clinically relevant non-major bleeding) at 3 months. The secondary outcome was symptomatic deep vein thrombosis. Results The most common reason for palliative care was cancer (90.7%). By 3 months, 1087 patients (91.3%) had died and 116 patients had presented at least one episode of clinically relevant bleeding (fatal in 23 patients). Taking into account the competing risk of death, the cumulative incidence of clinically relevant bleeding was 9.8% (95% confidence interval [CI], 8.3-11.6). Deep vein thrombosis occurred in six patients (cumulative incidence, 0.5%; 95% CI, 0.2-1.1). Cancer, recent bleeding, antithrombotic prophylaxis and antiplatelet therapy were independently associated with clinically relevant bleeding at 3 months. Conclusions Decisions regarding the use of thromboprophylaxis in palliative care patients should take into account the high risk of bleeding in these patients.

A Hospice and Palliative Care Bed Dedicated to Patients Admitted to the Emergency Department for End-of-Life Care.

A hospice and palliative care (PC) bed was created in 2006, located within a quiet area of our intensive care unit, in order to admit terminally ill patients sent to the emergency department (ED) for end-of-life care. We retrospectively analyze the records of the 342 terminally ill patients sent to the ED from 2007 to 2011. Among them, 176 (51.5%) were admitted to our hospice and PC bed, where 114 died. Besides, 99 (28.9%) of them died on stretchers in the ED. Our intervention led to a significant decrease in the number of terminally ill patients dying on stretchers in the ED. It also allowed both patients and families to have access to a more suitable environment.

Annual diagnosis rate of superficial vein thrombosis of the lower limbs: the STEPH community-based study.

BACKGROUND: The incidence of superficial vein thrombosis (SVT) in the general adult population remains unknown. OBJECTIVES: To assess the annual diagnosis rate of symptomatic, objectively confirmed lower limb SVT, associated or not with concomitant deep vein thrombosis and/or symptomatic pulmonary embolism. METHODS/PATIENTS: We conducted, from November 14, 2011, to November 13, 2012, a multicenter, community-based study in the Saint-Etienne urban area, France, representing a population of 265 687 adult residents (according to the 2009 census). All 248 general practitioners located within the area were asked to refer any patient with clinically suspected lower limb acute SVT to a vascular physician for systematic compression ultrasonography. All 28 vascular physicians located within the area participated in the study. The annual diagnosis rate, with the corresponding 95% confidence interval (CI), was calculated as the number of patients with symptomatic, objectively confirmed SVT divided by the number of person-years at risk defined by population data of the area. All venous thromboembolic events were validated by an independent central adjudication committee. RESULTS: Overall, 171 patients with symptomatic, confirmed SVT were reported. The annual diagnosis rate was 0.64& (95% CI, 0.55%-0.74&), was higher in women, and increased with advancing age regardless of gender [corrected]. Concomitant deep vein thrombosis (20 proximal) was observed in 42 patients (24.6% [95% CI, 18.3%-31.7%]), and concomitant symptomatic pulmonary embolism was observed in eight patients (4.7% [95% CI, 2.0%-9.0%]). CONCLUSIONS: This first community-based study showed that symptomatic SVT with confirmed diagnosis is a relatively common disease frequently associated with thromboembolic events in the deep venous system.

[No surgery without previous compression ultrasound in patients with a superficial venous thrombosis: a case of massive paradoxical embolism]. / Pas de chirurgie sans échographie préalable en cas de thrombose veineuse superficielle clinique : à propos d'un cas d'embolie paradoxale grave.

Lower limbs superficial venous thrombosis (LLSVT) is usually considered as common and of a benign prognosis. LLSVT can, however, be responsible for major thromboembolic complications: lower limbs deep vein thrombosis (LLDVT) and pulmonary embolism (PE). We report a case of a LLSVT complicated with a massive bilateral PE and an ischemic cerebral stroke, occurring immediately after a varicose vein surgery. Venous ultrasonography of the lower limbs must be systematically performed in case of LLSVT, in order to evaluate the presence of an associated LLDVT. A rigorous diagnostic and therapeutic approach is the only way to optimize the treatment of this disorder, and to avoid the occurrence of dramatic venous thromboembolic complications.

[Newly diagnosed multiple myeloma: Do we need to propose thromboprophylaxis?]. / Myélome multiple de novo : faut-il proposer une prophylaxie antithrombotique ?

The incidence of venous thromboembolism in multiple myeloma depends on the disease characteristics that include recent diagnosis, persistent or recurrent multiple myeloma, patient characteristics, and the type of treatment received such as thalidomide or lenalidomide especially in combination with high-dose dexamethasone, or combined chemotherapy. Currently, recommendations could be challenged by the results of the first randomized study evaluating aspirin, low molecular weight heparins and vitamin K antagonists in the antithrombotic prophylaxis. The recent data from the literature show that it is not possible to propose a therapeutic management for venous thromboembolism prophylaxis in multiple myeloma and that the use of antithrombotic prophylaxis may not be mandatory.

Value of TENS for relief of chronic low back pain with or without radicular pain.

OBJECTIVES: To evaluate the efficacy of transcutaneous electrical neurostimulation (TENS) in patients with chronic low back pain (LBP). DESIGN: Prospective, randomized, multicentre, single-blind study. SETTING: Twenty-one French pain centres. PARTICIPANTS: Two hundred thirty-six consecutive adult patients consulting for chronic LBP, with or without radicular pain (mean age ± standard deviation: 53 ± 13 years; range: 28-86 years). INTERVENTION: Patients were randomly assigned to receive either active (n = 117) or sham (n = 119) TENS in four 1-h daily treatment sessions for 3 months. MAIN OUTCOME MEASURES: The primary outcome measured was improvement of functional status at 6 weeks (Roland-Morris Disability Questionnaire). Secondary outcome measures were improvement of functional status at 3 months, pain relief (weekly visual analogue scale assessments), positive functional repercussions of pain levels on quality of life, a diminution of the use of analgesic and anti-inflammatory medication, satisfaction with the overall treatment strategy and compliance. RESULTS: Functional status did not differ between the groups, whether at 6 weeks or 3 months (p = 0.351 at 6 weeks). A significant improvement between the first and last visual analogue scale assessments was observed in patients with either lumbar pain alone or lumbar and radicular pain treated with active TENS. Other outcome measures did not differ significantly between the two groups. CONCLUSION: There was no functional benefit of TENS in the treatment of patients with chronic LBP.

[Postpartum reversible cerebral angiopathy: an unusual cause of headache]. / Angiopathie cérébrale aiguë réversible du post-partum : une cause particulière de céphalée aiguë du post-partum.

We present the case of a 34-year-old woman who developed, in postpartum period of an uncomplicated pregnancy, a thunderclap headache with visual disturbance associated with a severe arterial hypertension. Both clinical evolution and cerebral imaging including angio-MR confirmed the diagnosis of postpartum reversible vasoconstriction syndrome. One of the leading causes of this syndrome is the use of vasoactive drugs as it was observed in the case of this patient. It is important to consider this syndrome in the differential diagnosis in patients presenting with headache in the postpartum period.

Acute psychiatric syndrome leading young patients to ICU: consider anti-NMDA-receptor antibodies.

We report on a case of anti-N-Methyl-D-Aspartate receptor antibody encephalitis, and review cases and series previously published in the literature. Anti-N-Methyl-D-Aspartate receptor antibody encephalitis usually occurs in young female patients with no past medical history, in whom an ovarian teratoma is often detected. They subacutely develop predominantly psychiatric symptoms, followed by severe neurological disorders requiring transfer to the intensive care unit and prolonged ventilatory support. Complete or substantial recovery depends on early diagnosis, removal of the teratoma and immunotherapy. Our purpose is to focus intensivists' attention on this potentially lethal disorder, which should always be considered in young women admitted to the intensive care unit with characteristic neuropsychiatric disorders.

Short term effect of recombinant tissue plasminogen activator in patients with hemodynamically stable acute pulmonary embolism: results of a meta-analysis involving 464 patients.

UNLABELLED: By considering studies where a mixing of patients with and without shock, with or without invasive procedure, treated with various thrombolytic agents through different ways of infusion, have been included, current meta-analyses on thrombolysis efficacy in Pulmonary embolism (PE) are of limited value. Modern management of PE includes the use of both non-invasive diagnostic methods and intravenous rt-PA as thrombolytic agent. METHODS: We performed a meta-analysis of all randomized trials comparing rt-PA with heparin in patients with hemodynamically stable pulmonary embolism. Only the events clearly identified as related with the venous thromboembolic disease or with the treatment were considered. RESULTS: Five studies involving 464 patients were included. The pooled estimate from all the trials revealed a non-statistically significant reduction in death related to PE or pulmonary recurrence for rt-PA compared with heparin (3.5% versus 4.6%; RR 0.97, 95% CI 0.38 to 2.51, P for heterogeneity among the studies=0.73). Compared with heparin, rt-PA was not associated with a significant increase in major bleeding (4.9% versus 4.6%; RR 0.94, 95% CI 0.39 to 2.27). Similar results were found when only studies including patients with echocardiographic evidence of right ventricular dysfunction were considered. CONCLUSION: Neither mortality due to pulmonary embolism nor objective pulmonary embolism recurrence are decreased by rt-PA compared with heparin in patients with hemodynamically stable pulmonary embolism. No benefit is suggested in studies including patients with right ventricular dysfunction alone.

Thrombin generation and heparin-induced thrombocytopenia.

BACKGROUND: Heparin-induced thrombocytopenia (HIT) is a severe complication of heparin therapy. IgG antibodies targeting the platelet factor 4-heparin complex activate platelets and generate microparticles with procoagulant activity. OBJECTIVES: To determine whether the thrombin generation assay is capable of detecting procoagulant activity induced by patient platelet-poor plasma (PPP) in donor platelet-rich plasma (PRP). PATIENTS AND METHODS: We explored two groups of patients; group 1 (n = 23): patients with a positive clinical and biological diagnosis of HIT; group 2 (n = 25): patients with a negative clinical and biological diagnosis of HIT. Mixtures of donor PRP and patient PPP (1:1) were incubated either with unfractionated heparin 0.2 U mL(-1) or with physiological saline. Thrombin generation was assessed by calibrated thrombinography. The effect of heparin on the mixtures was evaluated according to the ratio of the values with and without heparin (wH/woH) of the five thrombogram parameters. RESULTS: With low heparin concentrations, plasma of group 1 activates donor platelets and generates procoagulant activity. A set of three ratios outside the cut-off values corresponds to the 'HIT thrombogram profile', characterized by a highly specific aspect of the thrombogram wH in relation to the thrombogram woH. None of the group 2 patients presented a HIT thrombogram profile. The results of thrombinography correlate well with the results of the platelet aggregation test. CONCLUSION: Our studies illustrate the central paradox of HIT, namely enhancement of thrombin generation in the presence of heparin. The HIT thrombogram profile as it is defined in this study can detect the procoagulant activity of HIT IgG antibodies.

Danaparoid cross-reactivity with heparin-induced thrombocytopenia antibodies: report of 12 cases.

PURPOSE: Danaparoid is a safe and effective drug for the treatment of heparin-induced thrombocytopenia (HIT). We describe an uncommon complication: danaparoid cross-reactivity with HIT antibodies. DESIGN AND SETTING: A retrospective observational multicenter study on HIT was conducted in France. In this study concerning HIT patients treated with lepirudin, 12 patients were treated with lepirudin because danaparoid cross-reacted with the heparin-dependent antibodies. RESULTS: Three groups of situations can be separated. In a first group, four patients received a short course of danaparoid until their initial functional HIT assay showed a cross-reactivity between danaparoid and HIT antibodies. One patient presented a fatal thrombotic complication but the relationship between this thrombotic complication and danaparoid cross-reactivity cannot be certain. In a second group, four patients received for 4 days at least a danaparoid treatment while the initial functional test did not show any danaparoid cross-reactivity. During danaparoid treatment, no significant increase of platelet count was observed and two patients presented a fatal thrombotic complication. In a third group, cross-reactivity between danaparoid and HIT antibodies was not checked before danaparoid therapy. During danaparoid treatment, no significant increase of platelet count was observed and the four patients developed a venous thromboembolic complication. CONCLUSION: Absence of any increase in platelet count after 3 to 5 days of danaparoid therapy and/or the occurrence of a new thrombotic event should lead to danaparoid cross-reactivity suspicion. However, before attributing thrombotic complications to danaparoid cross-reactivity, it is crucial to verify that the patients received the recommended danaparoid dosage regimen.