Definition,prediction,prevention and management of patients with severe ischemic stroke and large infarction

Severe ischemic stroke carries a high rate of disability and death.The severity of stroke is often assessed by the degree of neurological deficits or the extent of brain infarct,defined as severe stroke and large infarction,respectively.Critically severe stroke is a life-threatening condition that requires neurocritical care or neurosurgical intervention,which includes stroke with malignant brain edema,a leading cause of death during the acute phase,and stroke with severe complications of other vital systems.Early prediction of high-risk patients with critically severe stroke would inform early prevention and treatment to interrupt the malignant course to fatal status.Selected patients with severe stroke could benefit from intravenous thrombolysis and endovascular treatment in improving functional outcome.There is insufficient evidence to inform dual antiplatelet therapy and the timing of anticoagulation initiation after severe stroke.Decompressive hemicraniectomy(DHC)<48 h improves survival in patients aged<60 years with large hemispheric infarction.Studies are ongoing to provide evidence to inform more precise prediction of malignant brain edema,optimal indications for acute reperfusion therapies and neurosurgery,and the individualized management of complications and secondary prevention.We present an evidence-based review for severe ischemic stroke,with the aims of proposing operational definitions,emphasizing the importance of early prediction and prevention of the evolution to critically severe status,summarizing specialized treatment for severe stroke,and proposing directions for future research.

Expert consensus on prevention and cardiopulmonary resuscitation for cardiac arrest in COVID-19

Background:Cardiopulmonary resuscitation(CPR)strategies in COVID-19 patients differ from those in patients suffering from cardiogenic cardiac arrest.During CPR,both healthcare and non-healthcare workers who provide resuscitation are at risk of infection.The Working Group for Expert Consensus on Prevention and Cardiopulmonary Resuscitation for Cardiac Arrest in COVID-19 has developed this Chinese Expert Consensus to guide clinical practice of CPR in COVID-19 patients.Main recommendations:1)A medical team should be assigned to evaluate severe and critical COVID-19 for early monitoring of cardiac-arrest warning signs.2)Psychological counseling and treatment are highly recommended,since sympathetic and vagal abnormalities induced by psychological stress from the COVID-19 pandemic can induce cardiac arrest.3)Healthcare workers should wear personal protective equipment(PPE).4)Mouth-to-mouth ventilation should be avoided on patients suspected of having or diagnosed with COVID-19.5)Hands-only chest compression and mechanical chest compression are recommended.6)Tracheal-intubation procedures should be optimized and tracheal-intubation strategies should be implemented early.7)CPR should be provided for 20-30 min.8)Various factors should be taken into consideration such as the interests of patients and family members,ethics,transmission risks,and laws and regulations governing infectious disease control.Changes in management:The following changes or modifications to CPR strategy in COVID-19 patients are proposed:1)Healthcare workers should wear PPE.2)Hands-only chest compression and mechanical chest compression can be implemented to reduce or avoid the spread of viruses by aerosols.3)Both the benefits to patients and the risk of infection should be considered.4)Hhealthcare workers should be fully aware of and trained in CPR strategies and procedures specifically for patients with COVID-19.

Neurotransmitter receptors on microglia

As the resident immune cells in the central nervous system,microglia have long been hypothesised to promote neuroinflammation and exacerbate neurotoxicity.However,this traditional view has undergone recent revision as evidence has accumulated that microglia exert beneficial and detrimental effects depending on activation status,polarisation phenotype and cellular context.A variety of neurotransmitter receptors are expressed on microglia and help mediate the bidirectional communication between neurons and microglia.Here we review data supporting the importance of neurotransmitter receptors on microglia,with a special emphasis on glutamate,γ-aminobutyric acid(GABA),norepinephrine,cannabinoid and acetylcholine receptors.We summarise evidence favouring a significant role for neurotransmitter receptors in modulating microglial activation,phagocytic clearance and phenotypic polarisation.Elucidating the effects of neurotransmitter receptors on microglia and dissecting the underlying mechanisms may help accelerate the discovery of novel drugs that tap the therapeutic potential of microglia.