Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective To determine the application effect of esketamine pretreatment in laparoscopic high ligation of hernia sac in children.Methods A total of 70 children who received laparoscopic high ligation of hernia sac under general anesthesia were selected and divided into the control group and the observation group according to the random number table method,with 35 cases in each group.The control group received conventional general anesthesia,while the observation group was intravenously injected with 0.5 mg/kg of esketamine 15 minutes before the induction of general anesthesia.The preoperative anxiety score,respiratory mechanics indexes,lung injury status,anesthesia recovery,and adverse reactions during the awakening period were compared between the two groups.Results The anxiety scores of the observation group 10 minutes before anesthesia and immediately before anesthesia were significantly lower than those of the control group(P<0.05).The peak airway pressure and mean airway pressure of the observation group 30 minutes after establishing pneumoperitoneum and at the end of the operation were significantly lower than those of the control group(P<0.05).The levels of interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)at the end of the operation in the observation group were significantly lower than those in the control group(P<0.05).There was no statistically significant difference in the time of spontaneous breathing recovery,time to regain consciousness,tracheal extubation time,or post-anesthesia care unit(PACU)stay time between the two groups(P>0.05).The incidence of adverse reactions during the anesthetic awakening period in the observation group was significantly lower than that in the control group(P<0.05).Conclusion Esketamine pretreatment can significantly alleviate preoperative separation anxiety for children undergoing laparoscopic high ligation of hernia sac,reduce lung injury,and decrease airway pressure,which is beneficial to lung protection and postoperative anesthetic recovery,and has few adverse reactions.

Objective To determine the application effect of esketamine pretreatment in laparoscopic high ligation of hernia sac in children.Methods A total of 70 children who received laparoscopic high ligation of hernia sac under general anesthesia were selected and divided into the control group and the observation group according to the random number table method,with 35 cases in each group.The control group received conventional general anesthesia,while the observation group was intravenously injected with 0.5 mg/kg of esketamine 15 minutes before the induction of general anesthesia.The preoperative anxiety score,respiratory mechanics indexes,lung injury status,anesthesia recovery,and adverse reactions during the awakening period were compared between the two groups.Results The anxiety scores of the observation group 10 minutes before anesthesia and immediately before anesthesia were significantly lower than those of the control group(P<0.05).The peak airway pressure and mean airway pressure of the observation group 30 minutes after establishing pneumoperitoneum and at the end of the operation were significantly lower than those of the control group(P<0.05).The levels of interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)at the end of the operation in the observation group were significantly lower than those in the control group(P<0.05).There was no statistically significant difference in the time of spontaneous breathing recovery,time to regain consciousness,tracheal extubation time,or post-anesthesia care unit(PACU)stay time between the two groups(P>0.05).The incidence of adverse reactions during the anesthetic awakening period in the observation group was significantly lower than that in the control group(P<0.05).Conclusion Esketamine pretreatment can significantly alleviate preoperative separation anxiety for children undergoing laparoscopic high ligation of hernia sac,reduce lung injury,and decrease airway pressure,which is beneficial to lung protection and postoperative anesthetic recovery,and has few adverse reactions.

Objective To investigate the correlation between G protein-coupled receptor family C group 6 member A(GPRC6A)gene polymorphisms and their expression and pulmonary infections in elderly patients with chronic heart failure(CHF).Methods 138 elderly CHF patients admitted to the Xianyang First People's Hospital from January 2021 to January 2024 were selected as the research subjects,and were divided into an infected group(n=42)and an uninfected group(n=96)based on their lung infection status.Polymerase chain reaction(PCR)was used to detect polymorphisms at the rs6901250 and rs1606365 loci of the GPRC6A gene.The allele and genotype frequency distributions of the infected and uninfected groups were compared.Logistic regression modeling was used to analyze the s6901250 and rs1606365 loci under three genetic models(co-dominant,dominant and reces-sive)and lung infections in elderly patients with CHF.Real-time fluorescence quantitative PCR(RT-qPCR)method was used to detect the expression level of GPRC6A gene.The predictive value of the mRNA expression level of the GPRC6A gene for the development of pulmonary infections in elderly patients with CHF was analyzed by applying the receiver operator characteristic(ROC)curve.Results The distribution of genotypes at loci rs6901250 and rs1606365 of the GPRC6A gene in both the infected and uninfected groups of the lungs of elderly CHF patients conformed to the Hardy-Weinberg equilibrium law(χ2=0.199～0.376,all P>0.05),which was representative of the population.Compared with the uninfected group,the frequency of allele A at locus rs6901250(57.14%vs 41.67%)was significantly higher in the infected group,Allele G(54.76%vs.37.50%)and genotype GG(14.06%vs 29.99%)frequencies were significantly higher at locus rs1606365,and the differences were statistically significant(χ2=5.628,7.114,6.849,all P<0.05).At locus rs6901250,in the co-dominant model(GG vs AA)and the dominant model(GA+AA vs GG),the elderly CHF patients with AA genotype the risk of lung infection was higher than that of GG genotype(OR=1.753,1.546,all P<0.05);.rs1606365 locus showed that the risk of lung infection was higher than that of CC genotype in el-derly CHF patients with GG genotype under all three genetic models of co-dominant model(CC vs GG),dominant model(CG+GG vs CC)and recessive model(CG+CC vs GG)(OR=1.833,1.741,0.695,all P<0.05).The mRNA expression level of GPR-C6A gene in the lung-infected group of elderly CHF patients(1.43±0.35)was significantly higher than that in the uninfected group(1.02±0.21),and the difference was statistically significant(t=8.515,P<0.001).The results of the ROC curve analysis showed that the GPRC6A gene expression level predicted lung infection in elderly CHF patients with an AUC value of 0.895,a cut-offvalue of 1.37,and sensitivity and specificity of 85.7%and 66.7%,respectively.Conclusion The AA genotype at the rs6901250 locus and the GG genotype at the rs1606365 locus of the GPRC6A gene increased the risk of developing lung infec-tions in elderly patients with CHF.MRNA expression levels of the GPRC6A gene were elevated in the infected group,and its ex-pression level could be used as a predictive indicator for the development of lung infections in elderly patients with CHF.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective To design a VR-based air evacuation training system for simulating the on-board medical treatment process during air evacuation.Methods A VR-based air evacuation training system was developed which used 3D modeling technology to construct models of the medical aircraft cabin,medical devices and virtual characters to achieve scene interaction.The hardware part of the system included server computers,training terminal computers,VR equipment,3D fusion projection equipment,motion capture equipment,etc.The software of the system was developed using C++,UE4 Blueprint and C# programming languages,including two modules for medical treatment unit and medical treatment training process evaluation.The efficacy of the system was verified by the trials in air evacuation.Results The system developed successfully simulated the scenarios of tracheal tube dislodgement and increased intracranial pressure in the scenario model of open severe craniocerebral injury.The expert evaluation showed that the system gained advantages in training efficiency,low cost,safety,sense of immersion and recorded the operation data in real time to optimize the follow-up training.Conclusion The system developed delivers a virtual training environment with high-fidelity replication of real-mission conditions,enabling whole-course and immersive air evacuation drills.[Chinese Medical Equipment Journal,2025,46(3):15-20]

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.