Severe Metabolic Failures After Recreational Ingestion of γ-Butyrolactone

International audienceTo the Editorsγ-Butyrolactone (GBL) is a low-molecular chemical compound legally available for purchase with applications as an industrial solvent. This cheap and easy-to-obtain molecule is also a prodrug for γ-hydroxybutyrate (GHB), a synthetic agonist of GABA-B receptors with sedative and amnesic properties. γ-Butyrolactone is usually consumed in small doses in a recreational context, producing feelings of euphoria, a loss of inhibition, and enhanced sexual pleasure. Nonetheless, the difference between a recreational dose of GBL/GHB and a toxic or lethal dose is fairly narrow, which probably accounts for many overdoses involving this drug.[...

Platelets Are Critical Key Players in Sepsis

Host defense against infection is based on two crucial mechanisms: the inflammatory response and the activation of coagulation. Platelets are involved in both hemostasis and immune response. These mechanisms work together in a complex and synchronous manner making the contribution of platelets of major importance in sepsis. This is a summary of the pathophysiology of sepsis-induced thrombocytopenia, microvascular consequences, platelet-endothelial cells and platelet–pathogens interactions. The critical role of platelets during sepsis and the therapeutic implications are also reviewed

DataSheet_1_SARS-CoV-2 Omicron variant infection affects blood platelets, a comparative analysis with Delta variant.pdf

IntroductionIn November 2021, the SARS-CoV-2 Omicron variant of concern has emerged and is currently dominating the COVID-19 pandemic over the world. Omicron displays a number of mutations, particularly in the spike protein, leading to specific characteristics including a higher potential for transmission. Although Omicron has caused a significant number of deaths worldwide, it generally induces less severe clinical signs compared to earlier variants. As its impact on blood platelets remains unknown, we investigated platelet behavior in severe patients infected with Omicron in comparison to Delta.MethodsClinical and biological characteristics of severe COVID-19 patients infected with the Omicron (n=9) or Delta (n=11) variants were analyzed. Using complementary methods such as flow cytometry, confocal imaging and electron microscopy, we examined platelet activation, responsiveness and phenotype, presence of virus in platelets and induction of selective autophagy. We also explored the direct effect of spike proteins from the Omicron or Delta variants on healthy platelet signaling.ResultsSevere Omicron variant infection resulted in platelet activation and partial desensitization, presence of the virus in platelets and selective autophagy response. The intraplatelet processing of Omicron viral cargo was different from Delta as evidenced by the distribution of spike protein-positive structures near the plasma membrane and the colocalization of spike and Rab7. Moreover, spike proteins from the Omicron or Delta variants alone activated signaling pathways in healthy platelets including phosphorylation of AKT, p38MAPK, LIMK and SPL76 with different kinetics.DiscussionAlthough SARS-CoV-2 Omicron has different biological characteristics compared to prior variants, it leads to platelet activation and desensitization as previously observed with the Delta variant. Omicron is also found in platelets from severe patients where it induces selective autophagy, but the mechanisms of intraplatelet processing of Omicron cargo, as part of the innate response, differs from Delta, suggesting that mutations on spike protein modify virus to platelet interactions.</p

Suicide attempt with self-made <i>Taxus baccata</i> leaf capsules: survival following the application of extracorporeal membrane oxygenation for ventricular arrythmia and refractory cardiogenic shock

<p><b>Context:</b> Yew intoxication has been known for many years; high dose ingestion of <i>Taxus baccata</i> leads to cardiac toxicity mediated by calcium and sodium channel blocking properties. We present a case report of a patient who attempted suicide after <i>T. baccata</i> ingestion, causing refractory cardiogenic shock requiring temporary circulatory assistance by veno-arterial extra corporeal membrane oxygenation (VA ECMO).</p> <p><b>Case details:</b> A 28-year-old man was admitted to the critical care unit of a university hospital for arrhythmia after ingestion of self-made <i>T. baccata</i> leaf capsules. He rapidly developed cardiovascular collapse requiring mechanical ventilation, high dose intravenous catecholamines and electrical cardioversion. A femoro-femoral VA ECMO was implanted due to severe biventricular dysfunction and ventricular arrhythmia, associated with continuous renal replacement therapy. Taxol A, taxol B and baccatin III were detected and measured in both blood and urine samples by high-performance liquid chromatography tandem mass spectrometry, and kinetics suggested urinary excretion. Two days after hospital admission, VA ECMO and continuous renal replacement therapy were removed with full recovery of cardiac function.</p> <p><b>Discussion:</b> Our experience suggests that circulatory assistance by VA ECMO and continuous renal replacement therapy seem to be effective safe second-line therapeutic options in critically ill cases of severe yew intoxication with refractory cardiogenic shock due to arrhythmia.</p

Platelet <i>Versus</i> Megakaryocyte: Who Is the Real Bandleader of Thromboinflammation in Sepsis?

Platelets are mainly known for their key role in hemostasis and thrombosis. However, studies over the last two decades have shown their strong implication in mechanisms associated with inflammation, thrombosis, and the immune system in various neoplastic, inflammatory, autoimmune, and infectious diseases. During sepsis, platelets amplify the recruitment and activation of innate immune cells at the site of infection and contribute to the elimination of pathogens. In certain conditions, these mechanisms can lead to thromboinflammation resulting in severe organ dysfunction. Here, we discuss the interactions of platelets with leukocytes, neutrophil extracellular traps (NETs), and endothelial cells during sepsis. The intrinsic properties of platelets that generate an inflammatory signal through the NOD-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome are discussed. As an example of immunothrombosis, the implication of platelets in vaccine-induced immune thrombotic thrombocytopenia is documented. Finally, we discuss the role of megakaryocytes (MKs) in thromboinflammation and their adaptive responses

Kinetics of mean platelet volume predicts mortality in patients with septic shock

International audienceINTRODUCTION:Thrombocytopenia is well recognized as a poor prognosis sign associated with increased mortality and prolonged Intensive Care Unit (ICU) stay, particularly in septic patients. Mean platelet volume (MPV) could represent a relevant predictive marker of mortality. Here we investigated whether MPV kinetics during the first 15 days after hospital admission has a potential prognostic value for clinical outcome in septic shock.METHODS:We performed a retrospectively analysis of a cohort of 301 septic patients admitted in ICU. Three-month mortality was the primary endpoint. The prognostic value of the covariates of interest was ascertained by multidimensional analysis. We proposed a classification and regression trees analysis to predict survival probability.RESULTS:MPV kinetics was significantly different between 90-day survivors and non-survivors when followed during 15 days (except on day 3). 10-day MPV >11.6fL was an independent predictive factor of 90-day mortality (Hazard Ratio (HR) 3.796, 95% Confidence Interval (CI) [1.96-7.35], p = 0.0001) in multivariate analysis. Base excess on day 4 11.6fL was an independent predictive factor of 90-day mortality. This could be explained by the emergent response to acute platelet loss during septic shock, leading to megakaryocyte rupture to produce new but potentially immature platelets in the circulation. Therefore, continuous monitoring of MPV may be a useful parameter to stratify mortality risk in septic shock

Effect of combined individual-collective debriefing of participants in interprofessional simulation courses on crisis resource management: a randomized controlled multicenter trial.

International audienceInterprofessional simulation (IPS) training is an effective way to learn crisis resource management. The type of debriefing used in IPS training may affect participants' performance and their level of psychological safety. We aimed to assess and compare performance after standard collective debriefing versus a combination of individual and collective debriefing ("combined" approach)

Co-Infection and Ventilator-Associated Pneumonia in Critically Ill COVID-19 Patients Requiring Mechanical Ventilation: A Retrospective Cohort Study

International audienceConsidering virus-related and drug-induced immunocompromised status of critically ill COVID-19 patients, we hypothesize that these patients would more frequently develop ventilator-associated pneumonia (VAP) than patients with ARDS from other viral causes. We conducted a retrospective observational study in two intensive care units (ICUs) from France, between 2017 and 2020. We compared bacterial co-infection at ICU admission and throughout the disease course of two retrospective longitudinally sampled groups of critically ill patients, who were admitted to ICU for either H1N1 or SARS-CoV-2 respiratory infection and depicted moderate-to-severe ARDS criteria upon admission. Sixty patients in the H1N1 group and 65 in the COVID-19 group were included in the study. Bacterial co-infection at the endotracheal intubation time was diagnosed in 33% of H1N1 and 16% COVID-19 patients (p = 0.08). The VAP incidence per 100 days of mechanical ventilation was 3.4 (2.2–5.2) in the H1N1 group and 7.2 (5.3–9.6) in the COVID-19 group (p < 0.004). The HR to develop VAP was of 2.33 (1.34–4.04) higher in the COVID-19 group (p = 0.002). Ten percent of H1N1 patients and 30% of the COVID-19 patients had a second episode of VAP (p = 0.013). COVID-19 patients have fewer bacterial co-infections upon admission, but the incidence of secondary infections increased faster in this group compared to H1N1 patients