Objective:To explore the mechanism of dexmedetomidine (DEX) regulating microglial (MG) polarization and neuroinflammation after traumatic brain injury (TBI) in rats.Methods:Forty-two adult male SD rats were randomly (random number) divided into the sham group, TBI group, TBI+DEX group (further divided into 1 d, 3 d and 7 d subgroups), TBI+NF-κB inhibitor (pyrrolidine dithiocarbamate, PDTC) group and TBI+DEX+PDTC group, with 6 animals in each group. The rat TBI model was established according to the modified Feeney free fall method. PDTC was intraperitoneally injected 1 h after modeling with a dose of 100 mg/kg, and DEX was intraperitoneally injected 2 h after modeling with a dose of 100 μg/kg. Modified neurological severity score (mNSS) was used to evaluate rat neurological function, ELISA was used to detect serum inflammatory factors, and rats’ damaged cortex was collected to detect the phenotype markers of MG and protein expressions of MyD88 and NF-κB p65, and immunofluorescence staining was used to observe the expression and nuclear entry of NF-κB p65 in MG in injured cortex. One-way and two-way ANOVA were used to compare the measurement data among multiple groups.Results:Compared with the sham group, the mNSS score was significantly higher in the TBI group, and DEX treatment significantly decreased the mNSS score of TBI rats ( P<0.05). ELISA and Western blot results showed that in the TBI group, the tumor necrosis factor-α (TNF-α), interleukin (IL)-1β in serum and M1 phenotype marker (TNF-α, IL-1β) in brain were increased, the expression of anti-inflammatory factor IL-10 in serum and M2 phenotype markers (arginase-1 and IL-10) in brain were decreased ( P<0.05), and DEX downregulated the expression of TNF-α, IL-1β in serum and M1 phenotype markers in brain, while upregulated the level of L-10 in serum and the M2 phenotype marker in brain ( P<0.05). In addition, the expression of MyD88 and the nuclear translocation of NF-κB p65 were inhibited in the DEX group, and this effect could be enhanced by PDTC. Conclusions:DEX modulates MG activation in TBI rats by inhibiting NF-κB nuclear translocation and reduces neuroinflammation.

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.

Objective:To investigate the different outcomes of two types of acute kidney injury (AKI) according to standard of Kidney Disease: Improving Global Outcomes-AKI (KDIGO-AKI), and to analyze the risk factors that affect the prognosis of intensive care unit (ICU) patients in China.Methods:A secondary analysis was performed on the database of a previous study conducted by China Critical Care Clinical Trial Group (CCCCTG), which was a multicenter prospective study involving 3 063 patients in 22 tertiary ICUs in 19 provinces and autonomous regions of China. The demographic data, scores reflecting severity of illness, laboratory findings, intervention during ICU stay were extracted. All patients were divided into pure AKI (PAKI) and acute on chronic kidney disease (AoCKD). PAKI was defined as meeting the serum creatinine (SCr) standard of KDIGO-AKI (KDIGO-AKI SCr) and the estimated glomerular filtration rate (eGFR) at baseline was ≥ 60 mL·min -1·1.73 m -2, and AoCKD was defined as meeting the KDIGO-AKI SCr standard and baseline eGFR was 15-59 mL·min -1·1.73 m -2. All-cause mortality in ICU within 28 days was the primary outcome, while the length of ICU stay and renal replacement therapy (RRT) were the secondary outcome. The differences in baseline data and outcomes between the two groups were compared. The cumulative survival rate of ICU within 28 days was analyzed by Kaplan-Meier survival curve, and the risk factors of ICU death within 28 days were screened by Cox multivariate analysis. Results:Of the 3 063 patients, 1 042 were enrolled, 345 with AKI, 697 without AKI. The AKI incidence was 33.11%, while ICU mortality within 28 days of AKI patients was 13.91% (48/345). Compared with PAKI patients ( n = 322), AoCKD patients ( n = 23) were older [years old: 74 (59, 77) vs. 58 (41, 72)] and more critical when entering ICU [acute physiology and chronic health evaluation Ⅱ (APACHEⅡ) score: 23 (19, 27) vs. 15 (11, 22)], had worse basic renal function [eGFR (mL·min -1·1.73 m -2): 49 (38, 54) vs. 115 (94, 136)], more basic complications [Charlson comorbidity index (CCI): 3 (2, 4) vs. 0 (0, 1)] and higher SCr during ICU stay [peak SCr for diagnosis of AKI (μmol/L): 412 (280, 515) vs. 176 (124, 340), all P < 0.01]. The mortality and RRT incidence within 28 days in ICU of AoCKD patients were significantly higher than those of PAKI patients [39.13% (9/23) vs. 12.11% (39/322), 26.09% (6/23) vs. 4.04% (13/322), both P < 0.01], while no significant difference was found in the length of ICU stay. Kaplan-Meier survival curve analysis showed that the 28-day cumulative survival rate in ICU in AoCKD patients was significantly lower than PAKI patients (Log-Rank: χ2 = 5.939, P = 0.015). Multivariate Cox regression analysis showed that admission to ICU due to respiratory failure [hazard ratio ( HR) = 4.458, 95% confidence interval (95% CI) was 1.141-17.413, P = 0.032], vasoactive agents treatment in ICU ( HR = 5.181, 95% CI was 2.033-13.199, P = 0.001), and AoCKD ( HR = 5.377, 95% CI was 1.303-22.186, P = 0.020) were independent risk factors for ICU death within 28 days. Conclusion:Further detailed classification (PAKI, AoCKD) based on KDIGO-AKI SCr standard combined with eGFR is related to ICU mortality in critical patients within 28 days.

Objective To evaluate the effect of high flow nasal catheter oxygen (HFNCO) therapy on extubation failure rate,reintubation rate,and incidence of related complications within 48 h after extubation in mechanically ventilation patients.Methods A prospective,single-center,randomized controlled trial was conducted in the ICU of a teaching hospital affiliated to a medical university.A total of 77 patients with mechanical ventilation duration of ≥ 48 h and met the condition of spontaneous breathing test (SBT) were selected.The patients whose LUS ≥ 14 at 30 min of SBT were enrolled,and were randomly (random number) divided into 3 groups according to different oxygen therapies:the traditional oxygen therapy group,the noninvasive ventilation (NIV) group,and the HFNCO group.The effect of oxygen therapy and outcomes after extubation were compared among the three groups.The measurement data were presented as the mean±standard deviation (SD),and the numeration data were expressed as ratio or constituent ratio.The independent sample t test and LSD-t test were used for the comparisons between the two groups and the one-way ANOVA for differences between multiple groups.The differences between enumeration data were assessed by chi-square test.A P＜0.05 was considered statistically significant.Results There was no significant difference in gender,age and other general conditions between the two groups (P＞0.05).The NIV group and HFNCO group had lower extubation failure rate (14.29％,15.38％ vs 34.87％) and reintubation rate (10.7％,11.54％ vs 21.74％) than the convertional oxygen therapy group (P＜0.05).In addition,the traditional oxygen therapy group had longer mechanical ventilation duration [(24.33±4.42) d vs (8.58±1.09) d,(8.37±2.43) d],antibiotic use time [(19.21±4.37) d vs (8.34±2.54) d,(7.41±1.06) d],and ICU hospitalization time [(27.27±4.24) d vs (10.38±2.07) d,(9.44±0.79) d],all P＜0.05.Conclusions Treatment with HFNCO or NIV after extubation can effectively reduce the rates of extubation failure and reintubation,and improve the outcome of the mechanical ventilation.There is no difference in clinical efficiency between the NIV group and HFNCO group.However,compared with NIV,HFNCO can effectively reduce respiratory rate and avoid the retention of CO2,which has a wider application prospect in clinical practice.

Objective To study the predictive value of lung ultrasound score(LUS) on the extubation success rate in the patients with mechanical ventilation for early identifying the high risk patients with extubation failure and guiding the sequential therapy after extubation.Methods The prospective study method was adopted.Eighty-one cases with mechanical ventilation exceeding 48 h and successfully passing the spontaneous breathing trial(SBT) in EICU were selected.The bedside LUS evaluation was conducted before extubation.The cases were divided into the two groups according to whether successfully weaning.And the LUS differences before extubation were compared between the two groups.The receiver operating characteristic(ROC) curve was used to evaluate the predictive efficiency for extubation failure.Results The age and sex had no statistical difference between the two groups(P＞0.05).In included 81 cases,27 cases were failed to extubation and appeared different degrees of respiratory distress sign:respiratory rate(RR) increase,heart rate(HR) increase,SpO2 decrease,etc.,which needed non-invasive mechanical ventilation or high flow nasal cannula oxygen for alleviating respiratory difficulty.In the extubation failure group,10 cases were ineffective by above treatment and then needed reintubation.One case died within 24 h after extubation.Fifty-four cases succeeded in weaning and extubation.The LUS score was positively correlated with RR and PaCO2 (r=0.43,0.62;P＜0.05) and negatively correlated with SpO2 and PaO2(r=-0.76,-0.58;P＜0.05),while it was not correlated with HR and pH value(r=0.15,0.02,P＞0.05).The area under the ROC curve (AUC) of LUS score was 0.90(95％CI:0.84-0.95),it could be regarded that the accuracy of LUS for predicting extubation failure rate was stable,its sensitivity was 0.84 and specificity was 0.80.The diagnostic cutoff value was 15.00,if the LUS score exceeding 15 points,the extubation failure rate was significantly increased.Conclusion The LUS score has clinical application value for assessing the extubation success rate in the patients with mechanical ventilation.The patients with high risk of extubation failure can be early identified by the LUS score,which can guide the sequential therapy after extubation.

Objective To evaluate the clinical effects of ultrasound-guided internal jugular vein catheterization in long axis plane,short axis plane and oblique axis plane,in order to identify the opti-mal axis plane for this procedure.Methods One hundred and eighty patients (male 94 cases,female 86 cases,aged 34-82 years)requiring ultrasound-guided internal jugular vein catheterization were in-cluded in this study.They were randomly divided into three groups (n =60 each),long axis group, short axis group and oblique axis group,with 60 cases in each group.The details of catheterization in-cluding the time accessing into vein,the time finishing cannulation,needle redirecting times,number of skin points of puncture,puncture successful rate and complications in the three groups were recor-ded.Results Compared with long axis plane and short axis plane,the oblique axis plane was associat-ed with decreased time for venous access and cannulation.The oblique axis plane also needed less changes of needle direction.The complication of arterial puncture in the oblique axis plane group was significantly lower than long axis plane group and short axis plane group(P <0.05).The number of skin puncture points were similar between the three groups.Conclusion The oblique plane can provide a safe and more effective route to perform the IJV catheterization with minimal risk for carotid artery puncture,which demonstrates the practical superiority over the classic short axis plane and long axis plane for critically ill patients.

Objective To discuss the current status of application of the four kinds of clinical decision‐making method (mode recognition method ,hypothesis deductive method ,event‐driven method and applying regulation method ) in the clinical practice of the emergency resident doctors and to understand their mastery situation of the clinical decision‐making methods and the influencing factors .Methods One thousand and thirty‐five patients collected by 207 resident doctors (5 cases were randomly collected from the patients diagnosed and treated by each resident doctor ) were divided into 3 groups according to different year systems .The clinical decision‐making methods ,diagnosis accuracy of different clinical decision‐making methods and the influencing factors of decision‐making methods were compared among different grades .Results The difference in the decision‐making methods among different year systems had statistical significance (P<0 .05);furthermore ,the difference in the diagnostic accuracy among different decision‐making methods had statistical significance (P< 0 .05) ,the differences in the defensive behaviors and different decision‐making methods were statistically significant (P<0 .05) ,the multi‐classification Logistic regression of different decision‐making methods showed that the differences in the different residency year system ,residency education ,residency clinical contacting time ,inpatient symptoms ,defensive behaviors and interrogation reliability degree had statistical significance (P< 0 .05) .Conclusion The most commonly used decision‐making method by the resident doctors is the applying regulation method .The residency year system ,resi‐dency education ,residency clinical contacting time ,inpatient symptoms ,defensive behaviors and interrogation reliability degree are the influencing factors of application of the clinical decision‐making methods in the clinical practice of the emergency medicine spe‐cialty .

Objective To study the effect of combination mode of blood purification on insulin resistance in MODS patients and discuss the best mode of blood purification to improve insulin resistance in MODS patients.Methods A total of 60 MODS pa-tients were selected and randomly divided into control group(single mode of blood purification)and treatment group(combination mode of blood purification),each group of 30 cases.Blood glucose (BG),glucose standard deviation (BGSD),coefficient of variation of blood glucose (BGCV),regular insulin dosage (Ins),fasting insulin (FINS),insulin resistance index (HOMA-IR),HbA1c,C-re-active protein (CRP)was observed before and after treatment.Results BG,HbA1c,FINS,CRP,HOMA-IR,Ins of experimental group was lower than that of control group (P <0.05).After treatment,BG,FINS,CRP,HOMA-IR,Ins was declined in experi-mental group (P <0.05).After treatment,HbA1c was not changed in experimental group (P >0.05 ).Conclusion Combination mode blood purification may be more effective to insulin resistance in MODS patients.

Objective The purpose of this study was to analyze the relation of blood glucose variability and 28-day mortality in patients with different degree sepsis. Methods From September 1, 2010 to September 30, 2012, all adult patients diagnosed with sepsis and treated at least 3 days in Emergency ICU (EICU) of the first affiliated hospital of Kunming Medical University were enrolled in the study. Then the blood glucose levels and the other requisite clinical data were obtained from historical electronic medical records of patients excluding the patients reached exclusive criteria. The maximum and mean of blood glucose, and the glucose variability (the standard deviation,SD of blood glucose) in each patient were calculated. The patients were assigned according to severity of sepsis, then the relationship between SD of blood glucose and 28-day mortality was statistically assessed. Results There was an important correlation between SD of blood glucose and 28-day mortality (OR=4.237, =0.021) . The glucose variability increased with the serious of sepsis ( = 0.016) . Conclusion Glucose variability is an independent predictor of 28-day mortality in septic patients. In addition, the severity of sepsis has a positive correlation with blood glucose variability.

Objective To investigate the effect of breviscapine on the proliferation and the expression of thrombin receptor mRNA of vascular smooth muscle cells (VSMCs) . Methods Rat thoracic aortic VSMCs cultivated in vitro were randomly assigned to control,breviscapine 0.5 μg/mL, 5 μg/mL and 50 μg/mL groups, The proliferation was induced by thrombin, The proliferative effect of VSMCs was measured by the3H-thymidine (3H-TdR) incorporation method; the expression intensity of thrombin receptor mRNA relative to β-actin mRNA was detected by reverse transcription polymerase chain reaction (RT-PCR). Results The incorporation rate (cpm/1. 5 × 105 cells) of3H-TdR were 1 216. 00±241.57,673.25±12.63,602.50±80.59, and 522.00±103.99 respectively in the control, and breviscapine 0. 5 μg/mL, 5 μg/mL and 50 μg/mL groups. As compared with the control group, the prolifera-tion of rat thoracic aortic VSMCs was inhibited significantly in all breviscapine groups (all P<0.05). RT-PCR showed that the expressions of thrombin receptor mRNA relative to β-actin mRNA were 0. 614, 0. 389, 0. 310, and 0. 280 respectively in the control, and breviscapine 0. 5μg/mL, 5μg/mL and 50 μg/mL groups, The expression ratios of TR/β-actin mRNA in thoracic aortic VSMCs in all the breviscapine groups were lower than those in the control group, which suggesting that the expression of thrombin receptor mRNA was inhibited. Conclusions Breviscapine inhibits the proliferation of rat VSMCs. Its mechanism may he associated with the inhibition of the thrombin receptor gene expression of VSMCs.