Acute respiratory distress syndrome (ARDS), a fatal disease characterized by uncontrolled immune response and refractory hypoxemia, is most commonly induced by infection. Outer membrane vesicles (OMVs) are nanoparticles produced by gram-negative bacteria via the extrusion of the outer membrane and can deliver a range of bacterial molecules to host cells. Recently it was found that OMVs play vital roles in bacterial colonization, delivery of virulence factors, and disease pathogenesis. This article reviews the formation and biological functions of OMVs, and the inflammatory and pathological mechanisms of OMVs in ARDS.

The arrival of the era of evidence-based medicine makes critical care clinical randomized controlled trial (RCT) increase significantly, but RCT faces many problems and challenges, especially when recent several large clinical RCT appeared negative results with obvious clinical differences, causing a wide debate. The subsequent Bayesian reanalysis found that the corresponding treatment measures had obvious positive effect. This highlights the important role of Bayesian analysis in critical care clinical research. This review focuses on the application of Bayesian analysis in critical care clinical research.

Under the great challenge of public health emergencies, Critical Care Medicine is getting prosperous, integration of political courses into Critical Care Medicine is important. This paper summarizes the exploration and practice for integration of political courses into Critical Care Medicine.

With high plasticity, Th17 cells play a key role in immune imbalance in sepsis, which have been shown to harbor subgroups expressing a variety of characteristic transcription factors, such as Th1-like Th17 cells specifically expressing T-bet, may producing diverse transdifferentiation outcomes under different induction conditions. The transcription factor T-bet, as driver of Th1 cell differentiation, has been shown in recent years to inhibit Th17 cells differentiation by repressing the transactivation of Rorc. Thus, T-bet expression may influence transdifferentiation of Th17 cells, especially in infectious disease models, where T-bet knockout promotes Th17 cell differentiation and enhances immune response, loss of T-bet confers survival advantage to influenza-bacterial superinfection; besides, specific knockout of T-bet in mice Th17 cells impair Th17-to-Th1 transdifferentiation, resulting in increased bacterial load in the kidneys of CLP mice. This seemingly contradictory phenomenon suggests that T-bet, as a "Bridge" molecule in Th1 and Th17 cells differentiation, may enhance protective immune response or aggravate pathological immune responses under different situations. The function of transcription factor T-bet in Th17 cell differentiation is introduced, and the special role of T-bet in immune response is discussed, this review may provide a brand new immunological perspective for sepsis and other infectious diseases.

Sepsis is a vital disorder that threatens human life and health. Early and rational antibiotic use is essential for sepsis treatment. However, due to the wide variety of pathogens, rapid, comprehensive, and accurate identification of pathogens is a difficult task in diagnosis and treatment of sepsis. Traditional pathogenic surveillance often leads to delayed treatment or inappropriate antimicrobial therapy due to a narrow detection range, single target, low accuracy, low positive rate, and long detection period, making it challenging to meet the clinical needs of identifying the pathogens of serious infections. With its advantages of high throughput, comprehensive coverage, and high accuracy, mNGS can directly analyze the spectrum, abundance, and distribution of pathogenic microorganisms in specimens without bias and has shown great promise in the diagnosis and treatment of severe and complicated infectious diseases, such as identification of unknown pathogens, and drug resistance gene monitoring. This paper summarizes and reviews diagnostic applications of mNGS in various infectious diseases, the factors affecting detection and rational application in the pathogen diagnosis in sepsis.

Analgesia and sedation are crucial for critically ill patients. In recent years, a comprehensive strategy featuring prioritized analgesia, light sedation, delirium screening and prevention, early mobility and sleep improvement has been formed. However, a concise and easy-to-operate flow chart still needs to be improved. We have developed a protocolized process for pain and agitation management for critically ill patients to provide a hands-on tool in clinical practice.

To evaluate the value of electric sequential organ failure assessment (eSOFA), quick sequential organ failure assessment (qSOFA) and system inflammatory reaction syndrome (SIRS) scoring system in predicting the prognosis of patients with sepsis in the non-ICU environment.

Patients with sepsis in 10 non-ICU wards of Peking Union Medical College Hospital from October 2016 to March 2017 were prospectively analyzed. The clinical outcome of survival status 28 days after admission was taken as the prognostic index. The eSOFA, qSOFA and SIRS scores of the patients were calculated and the ROC curve was used to evaluate the prognostic value of eSOFA, qSOFA and SIRS scores.

A total of 193 patients met the Sepsis-3 diagnosis criteria. The AUROC of eSOFA, qSOFA and SIRS scores for predicting the prognosis of sepsis patients were 0.766 (95%CI: 0.700-0.824), 0.798 (95%CI: 0.700-0.896) and 0.589 (95%CI: 0.475-0.703) respectively. Among them, qSOFA had the best predictive performance, and both of qSOFA and eSOFA were better than SIRS.

In non-ICU wards, qSOFA performed best in predicting prognosis of sepsis patients, eSOFA is the next and SIRS is the worst.

Neurocritical care is an emerging specialty integrating critical care medicine and neuroscience. Neurocritical care specialty in China started late, due to lack of data on medical resources, and complex professional background of specialists in Neuro-critical care unit. Without standardized neurocritical care specialist training in China, there is an urgent need for neurocritical care specialist training. According to successful experience of previous specialized training in China and foreign countries, before establishing a standardized specialized training, priority should be given to core competencies in this specialty. A working Group from Neuro-Critical Care Committee affiliated to the Chinese Association of Critical Care Physicians and the National Center for Healthcare Quality Management in Neurological Diseases established the consensus through formal consensus methods (modified Delphi method and nominal group method). The working group first compiled the previous guidelines and then issued an online questionnaire. 1094 respondents from 33 provinces in China participated in the online survey. A formal list containing 329 statements was generated for rating by a nominal group. After five rounds of nominal group meetings and one round of comments and iterative review, 198 core competencies (54 on neurological diseases, 64 on general medical diseases, 42 on monitoring of practical procedures, 20 on professionalism and system management, 5 on ethical and legal aspects, 3 on the principles of research and certification, and 10 on scoring systems) formed the final list. The list can be used as a reference for neurocritical care training in the future.

Prone position ventilation (PPV) is a technique of respiratory support for patients under a prone position. PPV has the advantages of promoting collapsed alveolar recruitment, enhancing ventilation/perfusion ratio, improving respiratory system compliance, facilitating secretion drainage, and reducing ventilator-associated lung injury. However, there is no unified recommendations for the timing of PPV initiation. For patients with moderate and severe ARDS, PPV is now recommended by guidelines for mechanical ventilation of acute respiratory distress syndrome (ARDS). Considering that ventilator-associated lung injury complicates ARDS, PPV should be implemented as soon as possible for patients with traditional ARDS. For those receiving extracorporeal membrane oxygenation (ECMO), it is recommended to start PPV at the early stage of ECMO support in ECMO centers. The timing of PPV for intubated COVID-19 patients with poor respiratory compliance can refer to patients with traditional ARDS. The timing for awake PPV in COVID-19 gradually moves forward. Even if oxygenation does not dramatically drop, PPV can be started in COVID-19 patients as long as they are tolerable and have no contraindications.

The surviving sepsis campaign (SSC) guidelines has been updated five editions nowadays since it first published in 2004. SSC guidelines promote knowledge about sepsis constantly, which also improve management of sepsis to a certain extent, and become an important basis for guiding diagnosis and therapy in patients with sepsis. However, there are still several obvious defects in early resuscitation of septic shock in the SSC guidelines 2021, and the relevant recommendations may lead to misinterpretation or misuse. Therefore, "eight pitfalls" and relevant clinical evidence in SSC guidelines 2021 are discussed in present commentary.

Sepsis is defined as life-threatening organ dysfunction caused by adysregulated host response to infection, considered as a major global public health problem. Though relevant studies focused on Chinese sepsis epidemiology were not comprehensive, those studies still suggested that compared with high-income countries (HICs), the incidence and mortality of sepsis in China were relatively high, the long-term outcomes were poor and the burden of sepsis was heavy. This review of the current domestic sepsis epidemiology-related studies provides research directions for the adjustment of medical and health resources and future research.

Early effective and accurate antibiotic therapy is the key to reduce mortality of patients with severe infections. Identification of pathogenic microorganism is essential for appropriate antibiotic therapy. Metagenomics next generation sequencing (mNGS) is a novel pathogenic, diagnostic technology with fast detection speed, high accuracy, and comprehensive coverage. mNGS has been used to diagnose specific pathogenic microbial infections in recent years. However, many problems still need to be solved in the early target anti-microbial therapy of severe infections. This paper summarizes several problems that need to be considered in the use of mNGS in severe cases.

While nutrition therapy in critically ill patients has been improved in decades, continuous efforts to reach optimal nutrition therapy for each individual patient are still being made. Nutritional monitoring and assessment are important to analyze and understand the challenges of heterogeneity in critical ill patients. Measurable indicators of biological processes, pathogenic states, or metabolic responding to nutritional interventions can guarantee the achievement of optimal nutrition goal. More effective guidance to individualized nutrition therapy is to understand the interplay of pathophysiologic changes between nutrition, gastrointestinal tract, and critical illness. This article focuses on nutrition monitoring in critical ill patients during nutrition therapy and some nutritional biomarkers, and also discusses the feasibility and availability in the critical care setting.

Critically ill patients with COVID-19 at high altitudes were difficult to recognize and diagnose, due to hypoxemia associated with high altitudes and various chronic co-morbidities. In order to standardize the diagnostic and treatment practice, the present expert consensus was established by the method of consensus meeting, according to the Diagnostic and Treatment Regimen of COVID-19 (version 9), investigation advances abroad and domestic, and expert opinions, focusing on the common and important issues of diagnosis and treatment practice of critically ill patients with COVID-19 at high altitudes. This consensus will provide a reference for the standardized treatment of critically ill patients with COVID-19 at high altitudes in China.