Maresin1 improves hippocampal neuroinflammation and cognitive function in septic rats by activating the SLC7A11 / GPX4 ferroptosis signaling pathway.

Sepsis-associated encephalopathy (SAE) is a prevalent complication of sepsis, with hippocampal neuroinflammation playing a crucial role in SAE-induced cognitive impairment. Maresin1 (MaR1), a bioactive docosahexaenoic acid (DHA) metabolite, demonstrates comprehensive anti-inflammatory and neuroprotective attributes. Yet, its protective efficacy against SAE-induced cognitive decline remains unexplored. In this investigation, we implemented a rat SAE model via cecal ligation and puncture (CLP), while lipopolysaccharide (LPS) stimulation of HT22 cells simulated an in vitro SAE model; both models were pre-treated with MaR1. We evaluated rat learning and memory using a water maze, assessed hippocampal neuron damage via Nissl and FJC staining, and observed mitochondrial alterations through TEM. In vivo and in vitro assays gauged levels of Fe2+, MDA, GSH, and SOD. Additionally, Iba1 expression in the hippocampus was examined via immunofluorescence, while SLC7A11 and GPX4 protein expression levels were determined using western blot. Our findings indicated CLP-induced learning and memory impairment in rats, along with heightened ROS, Fe2+, and MDA levels in hippocampal neurons, diminished GSH and SOD levels, and down-regulated ferroptosis-related proteins (GPX4 and SLC7A11). Remarkably, MaR1 treatment attenuated these adverse effects. In LPS-stimulated HT22 cells, MaR1 lowered lipid ROS and bolstered mitochondrial membrane potential. Nonetheless, the ferroptosis inducer Erastin reversed MaR1's protective effects. Transwell experiments further showed MaR1's potential to inhibit microglia activation triggered by ferroptosis in HT22 cells. Consequently, MaR1 may mitigate hippocampal neuroinflammation via activating the SLC7A11/GPX4 ferroptosis signaling pathway, thus ameliorating SAE-related cognitive impairment.

Association of medical care capacity and the patient mortality of septic shock: a cross-sectional study.

BACKGROUND: Hospitals with higher septic shock case volume demonstrated lower hospital mortality. We conducted this study to investigate whether this phenomenon was only caused by the increase in the number of admissions or the need to improve the medical care capacity in septic shock at the same time. METHODS: Seven-hundred and eighty-seven hospitals from China collected in a survey from January 1, 2021 to December 31, 2021. Medical care capacity for septic shock was explored by patients with septic shock in intensive care units (ICU) divided into beds, intensivists, and nurses respectively. MAIN RESULTS: The proportion of ICU patients with septic shock was negatively associated with the patient mortality of septic shock (Estimate [95%CI], -0.2532 [-0.5038, -0.0026]) (p-value 0.048). The ratios of patients with septic shock to beds, intensivists, and nurses were negatively associated with mortality of septic shock (Estimate [95%CI], -0.370 [-0.591, -0.150], -0.136 [-0.241, -0.031], and -0.774 [-1.158, -0.389]) (p-value 0.001, 0.011 and < 0.001). Severe pneumonia, the most common infection that caused a septic shock, correlated positively with its mortality (Estimate [95%CI], 0.1002 [0.0617, 0.1387]) (p-value < 0.001). CONCLUSIONS: Hospitals with higher medical care capacity for septic shock were associated with lower hospital mortality.

Relationship between the Pre-ECMO and ECMO Time and Survival of Severe COVID-19 Patients: A Systematic Review and Meta-Analysis.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is the etiology of acute respiratory distress syndrome (ARDS). Extracorporeal membrane oxygenation (ECMO) is used to support gas exchange in patients who have failed conventional mechanical ventilation. However, there is no clear consensus on the timing of ECMO use in severe COVID-19 patients. OBJECTIVE: The aim of this study is to compare the differences in pre-ECMO time and ECMO duration between COVID-19 survivors and non-survivors and to explore the association between them. METHODS: PubMed, the Cochrane Library, Embase, and other sources were searched until 21 October 2022. Studies reporting the relationship between ECMO-related time and COVID-19 survival were included. All available data were pooled using random-effects methods. Linear regression analysis was used to determine the correlation between pre-ECMO time and ECMO duration. The meta-analysis was registered with PROSPERO under registration number CRD42023403236. RESULTS: Out of the initial 2473 citations, we analyzed 318 full-text articles, and 54 studies were included, involving 13,691 patients. There were significant differences between survivors and non-survivors in the time from COVID-19 diagnosis (standardized mean difference (SMD) = -0.41, 95% confidence interval (CI): [-0.53, -0.29], p < 0.00001), hospital (SMD = -0.53, 95% CI: [-0.97, -0.09], p = 0.02) and intensive care unit (ICU) admission (SMD = -0.28, 95% CI: [-0.49, -0.08], p = 0.007), intubation or mechanical ventilation to ECMO (SMD = -0.21, 95% CI: [-0.32, -0.09], p = 0.0003) and ECMO duration (SMD = -0.18, 95% CI: [-0.30, -0.06], p = 0.003). There was no statistical association between a longer time from symptom onset to ECMO (hazard ratio (HR) = 1.05, 95% CI: [0.99, 1.12], p = 0.11) or time from intubation or mechanical ventilation (MV) and the risk of mortality (highest vs. lowest time groups odds ratio (OR) = 1.18, 95% CI: [0.78, 1.78], p = 0.42; per one-day increase OR = 1.14, 95% CI: [0.86, 1.52], p = 0.36; HR = 0.99, 95% CI: [0.95, 1.02], p = 0.39). There was no linear relationship between pre-ECMO time and ECMO duration. CONCLUSION: There are differences in pre-ECMO time between COVID-19 survivors and non-survivors, and there is insufficient evidence to conclude that longer pre-ECMO time is responsible for reduced survival in COVID-19 patients. ECMO duration differed between survivors and non-survivors, and the timing of pre-ECMO does not have an impact on ECMO duration. Further studies are needed to explore the association between pre-ECMO and ECMO time in the survival of COVID-19 patients.

Prediction of mechanical ventilation outcome by early abdominal-visceral-blood-flow-and-function score in critically ill patients after cardiopulmonary bypass in the ICU: A prospective observational study.

Background: Abdominal organs are important organs that sense and respond to ischemia and hypoxia, but there are few evaluation methods.We use ultrasonography to evaluate abdominal organ function and blood flow in patients with mechanical ventilation (MV) after cardiopulmonary bypass and to obtain a semiquantitative score for abdominal organ function and blood flow. Methods: Patients with cardiopulmonary bypass in the Critical Care Department of Peking Union Medical College Hospital in China from March to July 2021 were enrolled in this prospective observational study. The correlation of the abdominal-visceral-blood-flow-and-function score (AVBFS) with the duration of MV, number of days spent in the intensive care unit (ICU), acute physiology and chronic health evaluation II (APACHE-II), sequential organ failure assessment (SOFA), lactate, epinephrine, and norepinephrine use was analyzed, and the results were used to assess the predictive value of the receiver operating characteristic curve (ROC) regression analysis score for the duration of MV. Results: Of the 92 patients who underwent cardiopulmonary bypass, 41 were finally included. The AVBFS were significantly correlated with the duration of MV, number of days spent in the ICU, APACHE-II score, SOFA score, and norepinephrine use time. The AVBFS in a group of patients using ventilators ≥36 h were significantly higher than those obtained for a group of patients using ventilators <36 h (P <0.05). The evaluation results for the AVBFS at 0-12 h after ICU admission were as follows: area under the ROC curve (AUC)=0.876 (95% confidence interval [CI]: 0.767 to 0.984), cut-off value=2.5, specificity=0.842, and sensitivity=0.773. Conclusions: Abdominal visceral organ function and blood perfusion can be used to evaluate gastrointestinal function. It is related to early and late extubation after cardiac surgery.

Blended teaching mode based on small private online course and case-based learning in analgesia and sedation education in China: a comparison with an offline mode.

BACKGROUND: Standardized training for pain, agitation-sedation, and delirium (PAD) management is urgently needed for Chinese intensivists' continuing education. Since 2020, because of the COVID-19 pandemic, the Chinese Analgesia and Sedation Education and Research (CASER) group has used an online blended teaching mode based on a small private online course (SPOC) and case-based learning (CBL). This study evaluated whether an online blended teaching mode has similar effects on PAD management training when an offline mode cannot be used. MATERIALS AND METHODS: Since 2020, the CASER group has provided offline training and online SPOC&CBL training three times each, targeting intensivists and ICU nurses in China. All participants were divided into an offline group and SPOC&CBL group. A final examination was offered in each training session to assess the students' mastery of professional knowledge. Teachers' and students' perceptions regarding the online SPOC&CBL mode were evaluated through questionnaires. RESULTS: Of all participants (n = 117), 106 completed all examinations and questionnaires. Most participants were aged 31-40 years (53, 50.0%), had an academic degree (60, 56.6%), and worked in a tertiary hospital (100, 94.34%). We assessed the learning effect on participants from two aspects: theory and clinical practice. There was no significant difference between the SPOC&CBL and offline groups in terms of theoretical, case analysis, and total scores (p > 0.05). In terms of the participants' perceptions regarding the SPOC&CBL mode, 91.5% considered the online mode to be a useful and accessible alternative to improve knowledge and skills. A total of 95.7% of the participants believed that they could interact well with group members, and 87.2% believed that they had a good degree of participation. Of these participants, 76.6% believed that they had received valuable learning resources. All instructors believed that the SPOC&CBL mode was more flexible than the offline mode in terms of teaching time and location, and they were all willing to carry out training with the SPOC&CBL mode. CONCLUSION: Compared to the offline mode, the SPOC&CBL mode can also enhance participants' knowledge and skills and meets their expectations. Therefore, an online mode can be considered a potential method in PAD management education in China.

Advances and Applications of Lung Organoids in the Research on Acute Respiratory Distress Syndrome (ARDS).

Acute Respiratory Distress Syndrome (ARDS) is a sudden onset of lung injury characterized by bilateral pulmonary edema, diffuse inflammation, hypoxemia, and a low P/F ratio. Epithelial injury and endothelial injury are notable in the development of ARDS, which is more severe under mechanical stress. This review explains the role of alveolar epithelial cells and endothelial cells under physiological and pathological conditions during the progression of ARDS. Mechanical injury not only causes ARDS but is also a side effect of ventilator-supporting treatment, which is difficult to model both in vitro and in vivo. The development of lung organoids has seen rapid progress in recent years, with numerous promising achievements made. Multiple types of cells and construction strategies are emerging in the lung organoid culture system. Additionally, the lung-on-a-chip system presents a new idea for simulating lung diseases. This review summarizes the basic features and critical problems in the research on ARDS, as well as the progress in lung organoids, particularly in the rapidly developing microfluidic system-based organoids. Overall, this review provides valuable insights into the three major factors that promote the progression of ARDS and how advances in lung organoid technology can be used to further understand ARDS.

Factors influencing DVT formation in sepsis.

INTRODUCTION: Sepsis is a global public health burden. Deep vein thrombosis (DVT) is the third most common cause of death from cardiovascular disease after heart attacks and strokes. We designed this experiment to investigate the factors influencing DVT formation in patients with sepsis. METHODS: In this survey, 918 septic patients admitted to Peking Union Medical College Hospital, who underwent DVT screening were enrolled. The data were collected from June 8, 2013 to October 12, 2022. The differences between septic patients with and without DVT were studied from following aspects: basic information, comorbidities, inflammatory cytokines, albumin, source of infection, sequential organ failure assessment (SOFA) score, coagulation and prognosis. MAIN RESULTS: In this study, the prevalence of DVT in patients with sepsis was 0.23. Elderly patients with sepsis were prone to DVT (p value < 0.001). In terms of comorbidities, septic patients with hypertension and atrial fibrillation were prone to DVT (p value 0.045 and 0.048). Inflammatory cytokines, such as procalcitonin (PCT), C-reactive protein (CRP), interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor (TNF)-α, had no significant correlation with DVT in patients with sepsis (p value 0.364, 0.882, 0.912, 0.789, 0.245, and 0.780). Levels of serum albumin correlated with DVT in patients with sepsis (p value 0.003). The SOFA total score had no relationship with DVT formation (p value 0.254). Coagulation and respiration function were negatively correlated with DVT (p value 0.018). Liver function was positively correlated with DVT (p value 0.020). Patients in the DVT group had longer duration of mechanical ventilation and longer intensive care unit (ICU) stays (p value < 0.001 and 0.006). There was no significant difference in survival in septic patients with and without DVT (p value 0.868). CONCLUSIONS: The SOFA total score had no relationship with DVT formation. The function of each organ had different effects on DVT formation. Better coagulation and respiration function, easier DVT formation. Poorer liver function, easier DVT formation. DVT was associated with longer duration of mechanical ventilation and longer ICU stays.

Quantitative electroencephalography predicts postoperative delirium in cardiac surgical patients after cardiopulmonary bypass: a prospective observational study.

Objective: Despite its frequency and associated negative effect, delirium remains poorly recognized in postoperative patients after ICU admission, especially among those who have undergone cardiac surgery with cardiopulmonary bypass. Postoperative delirium is triggered by a wide variety of acute medical conditions associated with impaired neuronal network connectivity. The lack of objective biomarkers primarily hinders the early detection of delirium. Seeking early biomarkers for tracking POD could potentially assist in predicting the onset of delirium and assessing the severity of delirium and response to interventions. Methods: QEEGs were taken from 46 sedated postoperative patients, with 24 of them having undergone cardiac surgery. The assessment of delirium was performed twice daily using the Confusion Assessment Method for the ICU (CAM-ICU) to screen for postoperative delirium (POD). QEEG data were interpreted clinically by neurophysiologists and processed by open-source EEGLAB to identify features in patients who had or did not have POD after cardiac or non-cardiac surgery. Results: The incidence of delirium in patients after undergoing cardiac surgery was nine times greater than in those after non-cardiac surgeries (41.7% vs. 4.5%; p = 0.0046). Patients with delirium experienced longer use of mechanical ventilation (118 h (78,323) compared to 20 h (18,23); p < 0.0001) and an extended ICU length of stay (7 days (6, 20) vs. 2 days (2, 4); p < 0.0001). The depth of anesthesia, as measured by RASS scores (p = 0.3114) and spectral entropy (p = 0.1504), showed no significant difference. However, notable differences were observed between delirious and non-delirious patients in terms of the amplitude-integrated EEG (aEEG) upper limit, the relative power of the delta band, and spectral edge frequency 95 (SEF95) (p = 0.0464, p = 0.0417, p = 0.0337, respectively). Conclusion: In a homogenous population of sedated postoperative patients, robust qEEG parameters strongly correlate with delirium and could serve as valuable biomarkers for early detection of delirium and assist in clinical decision-making.

Association between ICU quality and in-hospital mortality of V-V ECMO-supported patients-the ECMO quality improvement action (EQIA) study: a national cohort study in China from 2017 to 2019.

This cohort study was performed to explore the influence of intensive care unit (ICU) quality on in-hospital mortality of veno-venous (V-V) extracorporeal membrane oxygenation (ECMO)-supported patients in China. The study involved all V-V ECMO-supported patients in 318 of 1700 tertiary hospitals from 2017 to 2019, using data from the National Clinical Improvement System and China National Critical Care Quality Control Center. ICU quality was assessed by quality control indicators and capacity parameters. Among the 2563 V-V ECMO-supported patients in 318 hospitals, a significant correlation was found between ECMO-related complications and prognosis. The reintubation rate within 48 hours after extubation and the total ICU mortality rate were independent risk factors for higher in-hospital mortality of V-V ECMO-supported patients (cutoff: 1.5% and 7.0%; 95% confidence interval: 1.05-1.48 and 1.04-1.45; odds ratios: 1.25 and 1.23; P = 0.012 and P = 0.015, respectively). Meanwhile, the V-V ECMO center volume was a protective factor (cutoff of ≥ 50 cases within the 3-year study period; 95% confidence interval: 0.57-0.83, odds ratio: 0.69, P = 0.0001). The subgroup analysis of 864 patients in 11 high-volume centers further strengthened these findings. Thus, ICU quality may play an important role in improving the prognosis of V-V ECMO-supported patients.

Whole-process respiratory management strategies based on electrical impedance tomography in a pregnant woman with diffuse alveolar hemorrhage induced by systemic lupus erythematosus under veno-venous extracorporeal membrane oxygenation.

Electrical impedance tomography (EIT) as a bedside, noninvasive, radiation-free technology, could quantify alveolar collapse and over-distension and provide real-time ventilation images of lungs. Clinical studies have shown potential benefit in reducing lung injury by EIT to guide mechanical ventilation setting in acute respiratory distress syndrome (ARDS). The respiratory management of ARDS with venous-venous extracorporeal membrane oxygenation (VV ECMO) remains a challenge for ICU doctors. Moreover, EIT has gained great interests in the respiratory management in VV ECMO therapy. Here, EIT was used for respiratory management in the presented case of a 36-year-old gravida with systemic lupus erythematosus, who developed severe hypoxia caused by diffuse alveolar hemorrhage. Although the patient received mechanical ventilation, VV ECMO was further used for the refractory respiratory failure. EIT was applied to titrate positive end-expiratory pressure (PEEP), guide prone position and early mobilization, dynamic evaluating lung development during ECMO therapy. She was successfully rescued after comprehensive therapy. In summary, an EIT-guided whole-process respiratory management strategy that included PEEP titration, prone position, early mobilization, and dynamic lung ventilation monitoring was proposed. This case demonstrated that EIT-guided whole-process respiratory management strategy was feasible in the respiratory failure patient with VV ECMO therapy.

Multidimensional dynamic prediction model for hospitalized patients with the omicron variant in China.

Purpose: To establish dynamic prediction models by machine learning using daily multidimensional data for coronavirus disease 2019 (COVID-19) patients. Methods: Hospitalized COVID-19 patients at Peking Union Medical College Hospital from Nov 2nd, 2022, to Jan 13th, 2023, were enrolled in this study. The outcome was defined as deterioration or recovery of the patient's condition. Demographics, comorbidities, laboratory test results, vital signs, and treatments were used to train the model. To predict the following days, a separate XGBoost model was trained and validated. The Shapley additive explanations method was used to analyze feature importance. Results: A total of 995 patients were enrolled, generating 7228 and 3170 observations for each prediction model. In the deterioration prediction model, the minimum area under the receiver operating characteristic curve (AUROC) for the following 7 days was 0.786 (95% CI 0.721-0.851), while the AUROC on the next day was 0.872 (0.831-0.913). In the recovery prediction model, the minimum AUROC for the following 3 days was 0.675 (0.583-0.767), while the AUROC on the next day was 0.823 (0.770-0.876). The top 5 features for deterioration prediction on the 7th day were disease course, length of hospital stay, hypertension, and diastolic blood pressure. Those for recovery prediction on the 3rd day were age, D-dimer levels, disease course, creatinine levels and corticosteroid therapy. Conclusion: The models could accurately predict the dynamics of Omicron patients' conditions using daily multidimensional variables, revealing important features including comorbidities (e.g., hyperlipidemia), age, disease course, vital signs, D-dimer levels, corticosteroid therapy and oxygen therapy.

Enhancing Nix-dependent mitophagy relieves AKI by restricting TREM-1-mediated hyperactivation of inflammasome in platelets.

Platelets are highly involved in inflammation and organ injury under pathological conditions. The mitophagy in platelets may restrict hyperactivation of the inflammasome and relieve acute kidney injury (AKI). Cecal ligation puncture (CLP)/LPS-induced AKI Triggering receptor expressed on myeloid cells (TREM-1)-knockout mice models were established. Additionally, septic patients with AKI were also included. TREM-1 expression in platelets and inflammasome activation were examined. Platelet transfer assays were performed to investigate the contribution of platelet TREM-1 to renal injury. Mitophagy was evaluated in the context of inflammation. BNIP3L/Nix knockout mice were used to examine the relationship between platelet mitophagy and inflammatory activation. The results showed that the level of TREM-1 was increased and the platelet inflammasome was hyperactivated in CLP mice and septic patients, and TREM-1 activated platelet inflammasomes. TREM-1 deletion significantly abrogated hyperactivation of the platelet inflammasome and dramatically reduced AKI, whereas ablation of the mitophagy receptor BNIP3L/Nix induced the accumulation of damaged mitochondria and hyperactivation of platelet inflammasomes in CLP mice. BNIP3L/Nix controlled platelet inflammasome activation, and an amplification loop of platelet inflammasome activation and dysfunctional mitochondria controlled sepsis-related AKI. Therefore, targeting TREM-1 and NLRP3/BNIP3L in platelets may represent a novel therapeutic strategy for treating septic AKI.

A novel method for diaphragm-based electrode belt position of electrical impedance tomography by ultrasound.

BACKGROUND: This aim of study was to introduce a diaphragm-based EIT-belt placement method based on diaphragm position by ultrasound, and to evaluate the difference between diaphragm-based EIT-belt placement and conventional EIT-belt placement. METHOD: The diaphragm position (L0) determined by ultrasound was taken as zero reference level. The direction of headward is defined as positive, and toward feet is negative. For EIT data collection, the electrode belt was placed at 7 different levels, respectively (denoted as L-2 cm, L0, L2cm, L4cm, L6cm, L8cm, L10cm) at supine position in healthy volunteers. The diaphragm-based EIT-belt level (Lxcm) was defined where highest tidal impedance variation (TV) was achieved. Subsequently, EIT measurements were conducted at diaphragm-based EIT-belt levels and traditional EIT-belt level in 50 critically ill patients under mechanical ventilation. RESULT: The highest TV was achieved at L6cm and the smallest at L-2 cm., so the L6cm were taken as diaphragm-based EIT-belt level by ultrasound in 8 healthy volunteers. In 23 patients, the diaphragm-based EIT-belt plane agreed with the conventional planes (4th-6th ICS), which was defined as the Agreed group. Other patients were classified to the Disagreed group (above 4th ICS). The Disagreed group has a significantly higher BMI and lower global TV at the diaphragm-based EIT-belt plane compared to the Agreed group. CONCLUSIONS: The diaphragm-based EIT-belt position by ultrasound was feasible and resulted in different belt positions compared to the conventional position in > 50% of the examined subjects, especially in patients with higher BMI. Further study is required to validate the impact on EIT images with this novel method on clinical management.

Carbapenem is not always the best choice in the treatment of septic shock.

BACKGROUND: Septic shock is a global public health burden. In addition to the improvement of the level of individual care, the improvement of the overall hospital quality control management is also an essential key aspect of the Surviving Sepsis Campaign (SSC). Using of antibiotics is a cornerstone in the treatment of septic shock, so we conducted this study to investigate the influence of antibiotics and pathogenic bacteria on the mortality of septic shock at the level of overall hospital in China. METHODS: This was an observational database study in 2021 enrolled the data of 787 hospitals from 31 provinces/municipalities/autonomous regions of Mainland China collected in a survey from January 1, 2021 to December 31, 2021. RESULTS: The proportion of ICU patients with septic shock was 3.55%, while the patient mortality of septic shock was 23.08%. While carbapenem was the most preferred antibiotic medication used in 459 of the 782 hospitals, the preference for carbapenem did not show significant effect on the patient mortality in the treatment of septic shock (p-value 0.59). Compared with patients with fermenting bacteria as the most common pathogenic bacteria causing septic shock, patients with non-fermenting bacteria had a higher mortality (p-value 0.01). CONCLUSIONS: Whether using carbapenem as the preferred antibiotic or not, did not show effect on the patient mortality of septic shock. Compared with patients with fermenting bacteria as the most common pathogenic bacteria, patients of septic shock with non-fermenting bacteria had a higher mortality.

Measuring the worldwide spread of COVID-19 using a comprehensive modeling method.

BACKGROUND: With the global spread of COVID-19, detecting high-risk countries/regions timely and dynamically is essential; therefore, we sought to develop automatic, quantitative and scalable analysis methods to observe and estimate COVID-19 spread worldwide and further generate reliable and timely decision-making support for public health management using a comprehensive modeling method based on multiple mathematical models. METHODS: We collected global COVID-19 epidemic data reported from January 23 to September 30, 2020, to observe and estimate its possible spread trends. Countries were divided into three outbreak levels: high, middle, and low. Trends analysis was performed by calculating the growth rate, and then country grouping was implemented using group-based trajectory modeling on the three levels. Individual countries from each group were also chosen to further disclose the outbreak situations using two predicting models: the logistic growth model and the SEIR model. RESULTS: All 187 observed countries' trajectory subgroups were identified using two grouping strategies: with and without population consideration. By measuring epidemic trends and predicting the epidemic size and peak of individual countries, our study found that the logistic growth model generally estimated a smaller epidemic size than the SEIR model. According to SEIR modeling, confirmed cases in each country would take an average of 9-12 months to reach the outbreak peak from the day the first case occurred. Additionally, the average number of cases at the peak time will reach approximately 10-20% of the countries' populations, and the countries with high trends and a high predicted size must pay special attention and implement public health interventions in a timely manner. CONCLUSIONS: We demonstrated comprehensive observations and predictions of the COVID-19 outbreak in 187 countries using a comprehensive modeling method. The methods proposed in this study can measure COVID-19 development from multiple perspectives and are generalizable to other epidemic diseases. Furthermore, the methods also provide reliable and timely decision-making support for public health management.

Incorporating electrical impedance tomography to transpulmonary pressure-guided PEEP in severe ARDS with pneumothorax and multiple cavitations: a case report.

Pneumothorax is a potentially fatal complication in patients with acute respiratory distress syndrome (ARDS), presenting challenges in determining the optimal positive end-expiratory pressure (PEEP) level to prevent atelectasis without exacerbating the pneumothorax. This case report describes the successful application of transpulmonary pressure and electrical impedance tomography (EIT) at the bedside to guide PEEP selection in a patient with ARDS complicated by pneumothorax due to methicillin-resistant Staphylococcus aureus infection. By using minimal PEEP to maintain positive end-expiratory transpulmonary pressure and visualizing lung reopening with EIT, the optimal PEEP level was reaffirmed, even if traditionally considered high. The patient's condition improved, and successful weaning from the ventilator was achieved, leading to a transfer out of the intensive care unit. Clinical trial registration: https://clinicaltrials.gov/show/NCT04081142, identifier NCT04081142.

Initial 24-h perfusion index of ICU admission is associated with acute kidney injury in perioperative critically ill patients: A retrospective cohort analysis.

Background: The relationship between perfusion index (PI) and organ dysfunction in patients in the intensive care unit (ICU) is not clear. This study aimed to explore the relationship between PI and renal function in the perioperative critical care setting and evaluate the predictive efficiency of PI on patients with acute kidney injury (AKI) in the ICU. Methods: This retrospective analysis involved 12,979 patients who had undergone an operation and were admitted to the ICU in Peking Union Medical College Hospital from January 2014 to December 2019. The distribution of average PI in the first 24 h after ICU admission and its correlation with AKI was calculated by Cox regression. Receiver operating characteristic (ROC) curves were generated to compare the ability of PI, mean arterial pressure (MAP), creatinine, blood urea nitrogen (BUN), and central venous pressure (CVP) to discriminate AKI in the first 48 h in all perioperative critically ill patients. Results: Average PI in the first 24 h served as an independent protective factor of AKI (Odds ratio [OR]=0.786, 95% confidence interval [CI]: 0.704-0.873, P <0.0001). With a decrease in PI by one unit, the incidence of AKI increased 1.74 times. Among the variables explored for the prediction of AKI (PI, MAP, creatine, BUN, and CVP), PI yielded the highest area under the ROC curve, with a sensitivity of 64.34% and specificity of 70.14%. A cut-off value of PI ≤2.12 could be used to predict AKI according to the Youden index. Moreover, patients in the low PI group (PI ≤2.12) exhibited a marked creatine elevation at 24-48 h with a slower decrease compared with those in the high PI group (PI >2.12). Conclusions: As a local blood flow indicator, the initial 24-h average PI for perioperative critically ill patients can predict AKI during their first 120 h in the ICU.

Importance of clinical parameters for cultivation of critical care thinking by online teaching of critical care medicine.

BACKGROUND: The teaching of critical care medicine is a very important task, especially during the COVID-19 pandemic. The understanding of critical care parameters is the foundation and core, which is conducive to the formation of clinical thinking. This study is to evaluate the training effect of teaching of critical care parameters based on an online platform, and explore the teaching methods of critical care medicine that can help to cultivate trainees' clinical thinking and practical ability. METHODS: Questionnaires were released before and after the training through the official new media platform "Yisheng" application (APP) of China Medical Tribune involving 1109 participants. The trainees who filled in the questionnaire in APP and received training were randomly selected as the investigated population. Statistical description and analysis were carried out using SPSS 20.0 and Excel 2020. RESULTS: The trainees were mainly attending physicians in tertiary hospitals and above. Among all critical care parameters, trainees paid more attention to critical hemodynamics, respiratory mechanics, severity of illness scoring systems, critical ultrasound, and critical hemofiltration. The degree of satisfaction with the courses was high, especially the course of critical hemodynamics was scored the highest. The trainees believed that the course contents were of great help to clinical work. However, no significant difference was found in the trainees' understanding or cognition of the connotation of the parameters before and after the training. CONCLUSION: Teaching of critical care parameters based on an online platform is conducive to improving and consolidating the clinical care ability of trainees. However, it is still necessary to strengthen the cultivation of clinical thinking in critical care. In the future, the integration of theory with practice must be strengthened in clinical practice, ultimately achieving the homogeneous diagnosis and treatment of patients with critical illness.

Tissue oxygen saturation is predictive of lactate clearance in patients with circulatory shock.

BACKGROUND: Tissue oxygen saturation (StO2) decrease could appear earlier than lactate alteration. However, the correlation between StO2 and lactate clearance was unknown. METHODS: This was a prospective observational study. All consecutive patients with circulatory shock and lactate over 3 mmol/L were included. Based on the rule of nines, a BSA (body surface area) weighted StO2 was calculated from four sites of StO2 (masseter, deltoid, thenar and knee). The formulation was as follows: masseter StO2 × 9% + (deltoid StO2 + thenar StO2) × (18% + 27%)/ 2 + knee StO2 × 46%. Vital signs, blood lactate, arterial and central venous blood gas were measured simultaneously within 48 h of ICU admission. The predictive value of BSA-weighted StO2 on 6-hour lactate clearance > 10% since StO2 initially monitored was assessed. RESULTS: A total of 34 patients were included, of whom 19 (55.9%) had a lactate clearance higher than 10%. The mean SOFA score was lower in cLac ≥ 10% group compared with cLac < 10% group (11 ± 3 vs. 15 ± 4, p = 0.007). Other baseline characteristics were comparable between groups. Compared to non-clearance group, StO2 in deltoid, thenar and knee were significantly higher in clearance group. The area under the receiver operating curves (AUROC) of BSA-weighted StO2 for prediction of lactate clearance (0.92, 95% CI [Confidence Interval] 0.82-1.00) was significantly higher than StO2 of masseter (0.65, 95% CI 0.45-0.84; p < 0.01), deltoid (0.77, 95% CI 0.60-0.94; p = 0.04), thenar (0.72, 95% CI 0.55-0.90; p = 0.01), and similar to knee (0.87, 0.73-1.00; p = 0.40), mean StO2 (0.85, 0.73-0.98; p = 0.09). Additionally, BSA-weighted StO2 model had continuous net reclassification improvement (NRI) over the knee StO2 and mean StO2 model (continuous NRI 48.1% and 90.2%, respectively). The AUROC of BSA-weighted StO2 was 0.91(95% CI 0.75-1.0) adjusted by mean arterial pressure and norepinephrine dose. CONCLUSIONS: Our results suggested that BSA-weighted StO2 was a strong predictor of 6-hour lactate clearance in patients with shock.