Neurocritical care involves complex pathophysiological mechanisms, and its incidence is higher, injuries are more severe, and treatment is more challenging in high-altitude environments. This consensus, based on the latest domestic and international evidence-based medical data, establishes a standardized, goal-oriented framework for neurocritical care management applicable in high-altitude regions and nationwide. The consensus was developed following international standards for evidence quality assessment and underwent two rounds of Delphi expert consultation, resulting in 32 recommendation statements covering three parts: management systems, monitoring and assessment, and core strategies. Key updates include: advocating for the establishment of independent neurocritical care units and implementing precise tiered diagnosis and treatment based on the "Five Differences in Critical Care" concept; constructing a "trinity" multimodal brain monitoring system centered on cerebral blood flow, cerebral oxygenation, and brain function, emphasizing routine bedside transcranial Doppler ultrasound, cerebral oximetry, and continuous electroencephalography monitoring; shifting management strategies from mild hypothermia therapy to targeted temperature management, and defining the "446" target management pathway for the supercritical stage; emphasizing the assessment of static and dynamic cerebrovascular autoregulation functions through multimodal methods to achieve individualized optimal mean arterial pressure management; elevating cerebrospinal fluid management goals to the level of "glymphatic system" function maintenance; implementing a multidisciplinary collaborative, whole-process management model focusing on patients' long-term neurological functional outcomes; de-escalation criteria include multidimensional indicators such as recovery of brain structure, restoration of cerebrovascular autoregulation, improvement in cerebrospinal fluid dynamics, and reduction in biomarker levels; and integrating cutting-edge technologies like artificial intelligence into post-critical care management and rehabilitation planning. This consensus systematically integrates the entire process of neurocritical care management, reflecting the modern connotation of goal-oriented, dynamic, and multimodal integration in neurocritical care medicine. It aims to adapt to new trends such as deepening understanding of pathophysiological mechanisms, the integration of medicine and engineering, and the empowerment of artificial intelligence, thereby further advancing the discipline of critical care medicine.

Objective:To investigate the efficacy of vital pulp therapy versus pulp revascularization in the treatment of irreversible pulpitis and apical periodontitis in young permanent teeth. Methods:This study used a retrospective design. Fifty-six children with irreversible pulpitis and apical periodontitis in young permanent teeth, admitted to Shaoxing Stomatological Hospital from January 2022 to June 2024, were selected for the study. The children were divided into Group A ( n = 28) and Group B ( n = 28) based on treatment methods. Group A received vital pulp therapy, while Group B underwent pulp revascularization. The efficacy of both groups was compared 12 months after surgery. The root length and apical foramen size were compared between the two groups before surgery, as well as 3 and 12 months after surgery. The imaging findings were also compared between the two groups 3 and 12 months after surgery. Results:There was no significant difference in efficacy between the two groups ( P>0.05). The root lengths in Group A at 3 and 12 months after surgery were (13.17 ± 1.52) mm and (14.34 ± 1.68) mm, respectively, which were significantly greater than those in Group B [(11.86 ± 1.29) mm, (13.09 ± 1.45) mm; t = 3.48, 2.98, both P<0.05]. The apical foramen sizes in Group A at 3 and 12 months after surgery were (2.17 ± 0.32) mm and (1.61 ± 0.27) mm, respectively, and were significantly smaller than those in Group B [(2.53 ± 0.37) mm, (1.98 ± 0.31) mm; t = -7.03, -4.76, both P<0.05]. The proportion of children with an open apical foramen in Group A at 3 months after surgery was significantly lower than that in Group B [35.71% (10/28) vs. 64.29% (18/28); χ2 = 4.57, P<0.05). However, there was no statistically significant difference in the proportion of open apical foramina between the two groups at 12 months after surgery ( P>0.05). Conclusions:Vital pulp therapy shows good efficacy in the treatment of irreversible pulpitis and apical periodontitis in young permanent teeth. Compared with pulp revascularization, vital pulp therapy can remarkably reduce apical foramen size and increase root length, making it a valuable option for clinical practice.

Aim To investigate the effect of eplerenone(EPL)on the alleviation of rheumatoid arthritis(RA)based on voltage-gated potassium channel 1.3(Kv1.3)/B-cell lymphoma-2(Bcl-2)/nuclear factor-κB(NF-κB)to inhibit macrophage M1 polarization in mice.Methods Bioinformatics technology was used to screen disease pathways and targets,and the binding affinity and stability of EPL-Kv1.3 complex system were calculated.A mouse model of RA was established and treated with EPL by intragastric administration for 42 days.The indicators reflecting drug remission of RA were recorded and detected.RAW264.7 cells were treated with EPL to detect the indicators reflecting the effect of drugs on macrophage M1 polarization,and to verify the upstream and downstream key targets of re-lated signaling pathways mediated by drugs.Results Bioinformatics analysis showed that the disease targets were mainly involved in inflammatory response and NF-κB signaling pathway,and EPL-Kv1.3 had high affinity and stable binding.In animal experiments,the detec-tion of anti-cyclic citrullinated peptide antibody(CCP-Ab)and joint score indicated the successful establish-ment of the model.Compared with the model group,EPL could reduce the toe redness and swelling score,alleviate the plantar redness and swelling,synovial swelling,and reduce fibrosis and inflammatory cell in-filtration in mice.The medium-dose and high-dose EPL groups reduced the HE staining score(P＜0.05,P＜0.01),and the high-dose EPL group reduced the serum RF in mice(P＜0.01).CCK-8 results showed that low,medium and high doses of EPL had no effect on the activity of RAW264.7 macrophages(P＞0.05).Compared with the model group,EPL treatment significantly reduced the contents of IL-6,TNF-α and NO in supernatant of the cells(P＜0.01),reduced the nuclear translocation of NF-KB-p65 in the high-dose EPL group,reduced the M1 polarization and increased the proportion of M2 polarization in the medium and high-dose EPL groups(P＜0.01).The mRNA levels of MyD88,IκB-α,NF-κB-p65,NF-KB-p50,IL-1 β and iNOS were significantly reduced in each dose group of EPL(P＜0.01).EPL significantly increased the pro-tein expression of Bcl-2(P＜0.01)and decreased the protein expression of Kv1.3,MyD88,p-IκB-α/IκB-α,p-p65/p65,IL-1 β and iNOS(P＜0.05).Conclusion EPL may play an immunomodulatory role in relieving RA in mice by regulating Kv1.3/Bcl-2/NF-κB path-way,reducing macrophage M1 polarization and amelio-rating macrophage-associated inflammatory response.

An assay was established for detection of toxigenic Clostridioides difficile by combining microfluidic chip analysis with immunochromatography,and its performance was evaluated and compared with those of the Xpert C.difficile/Epi and VIDAS CD AB tests.Primer pairs were designed according to the tcdB and tpi genes in C.difficile.The specificity,limit of detection,reproducibility,and stability were evaluated.A total of 215 stool samples from patients with diarrhea were collected and tested in parallel with the Xpert C.difficile/Epi,VIDAS CDAB,and our assay.C.difficile was isolated from samples,and the tcdB gene was identified when discrepant results were obtained from the three above assays.Our assay showed no cross-reaction with other diarrhea-associated pathogens.Its reproducibility was 100％in testing of two standard plasmids containing tcdB and tpi genes at two concentrations(105 and 102 copies/μL).Two standard plasmids were detected after the PCR and immunochromatography reagents had been stored for 3,6,9,and 12 months,and all the results were posi-tive.The limit of detection was 10 copies/μL for toxigenic C.difficile.Testing of 33 samples positive for C.difficile with our assay(33/215,15.3％)yielded findings statistically coherent with those of the Xpert C.difficile/Epi test(kappa value=0.965).The sensitivity,specificity,positive predictive value,and negative predictive value of our assay,with respect to Xpert C.difficile/Epi as the standard,were 94.3％,100.0％,100.0％,and 98.9％;these values were significantly higher than those of VIDAS CDAB(60.0％,98.9％,91.3％,and 92.7％)(Kappa=0.714,OR=157.50,95％CI:62.03-847.28,P=0.013).In conclusion,our newly developed assay is specific,stable,and reproducible,and may be used for rapid and accu-rate detection of toxigenic C.difficile.The assay could be used for C.difficile infection screening in outpatient and emergen-cy,community medical service center,and epidemiological settings.

AIM To study the chemical constituents from the water fraction of rhizoma of Smilax trinervula Miq.and their biological activities.METHODS Polyamide,silica gel,Sephadex LH-20,ODS and semi-preparative HPLC were used for isolation and purification,then the structures of obtained compounds were identified by physicochemical properties and spectral data.The antitumor activities were determined by MTT mothod,and the inhibitory activities on α-glucosidase were determined by PNPG method.RESULTS Eleven compounds were isolated and identified as tyrosine(1),uridine(2),2-(2',3',4'-trihydroxybutyl)-6-(2",3",4"-trihydroxybutyl)-pyrazine(3),2-(1',2',3',4'-tetrahydroxybutyl)-6-(2",3",4"-trihydroxybutyl)-pyrazine(4),2-(1',2',3',4'-tetrahydroxybutyl)-5-(2",3",4"-trihydroxybutyl)-pyrazine(5),uracil(6),2-(1',2',3',4'-tetrahydroxybutyl)-5-(1",2",3",4"-tetrahydroxybutyl)-pyrazine(7),dioscin(8),shikimic acid(9),pyrazine(10),3,4-dihydroxyphenyethyl alcohol 8-O-β-D-glycopyranoside(11).The IC50 values of compounds 8 to human breast cancer cell MCF-7 was(2.36±0.26)μg/mL,and the IC50 values of compounds 3-5 and 7 to α-glucosidase were(1.54±0.15)-(10.53±0.38)μg/mL.CONCLUSION Compounds 1-7,10 are isolated from Smilax genus for the first time,and compound 9,11 are first isolated from this plant.Compound 8 has anti-tumor activity,and compounds 3-5,7 have α-glucosidase inhibitory activities.

Objective To analyze the correlation between lesion volume,lesion mass,and maximum lesion diameter in the assessment of advanced hepatocarcinoma with lung metastasis,and to evaluate the application value of total volume response and total mass response of lung metastatic lesions in efficacy assessment.Methods A retrospective analysis was conducted on the CT imaging data of 20 patients clinically confirmed with hepatocarcinoma and lung metastases,followed by subsequent follow-up to monitor their survival outcomes.Volume measurement software was used to measure the volume of lesions before and after treatment.We recored lesion diameter,volume measurements and CT values,calculated the mass of the lesions.The correlation between lesion volume,mass and diameter was analyzed,as well as the correlation between the change rates of volume,mass and lesion diameter.Additionally,the total volume and total mass of all lesions were calculated.The correlation between the change rates of total volume/total mass and the change rate of pulmonary lesion diameter under the RECIST 1.1 criteria,as well as the correlation with changes in patients'tumor markers,were analyzed.Furthermore,the overall volume response and overall mass response of lesions were evaluated based on changes in total volume and total mass,and their consistencies with the RECIST 1.1 criteria for efficacy evaluation were analyzed.Finally,univariate Cox regression analysis was performed to explore the association between these variables and patient survival outcomes.Results There was strong correlation between lesion volume,mass and tumor diameter(r=0.771,0.775),between the rate of change in mass and the rate of change in lesion diameter(r=0.846),and between the rates of change in total volume/total mass and the rate of change in pulmonary lesion diameter under the RECIST 1.1 criteria(r=0.800,0.896).The correlation between the rates of change in total volume/total mass and patients'tumor markers was not statistically significant.There was moderate correlation between the rate of change in volume and the rate of change in lesion diameter(r=0.692).The evaluation results of total volume response and total mass response for pulmonary lesions in advanced hepatocarcinoma with lung metastasis were generally consistent with the RECIST 1.1 criteria(Kappa=0.486,0.426).Univariate Cox regression analysis revealed that total lesion volume(P=0.047)and total lesion mass(P=0.049)were independent prognostic factors for survival outcomes.Conclusion Lesion volume,mass,and diameter,as well as their respective change rates,were found to be interrelated.Furthermore,total lesion volume and total lesion mass were identified as independent prognostic factors for survival outcomes.The total volume response and total mass response are promising evaluation methods in evaluating the efficacy of lung metastasis of hepatocarcinoma,which are different from the RECIST 1.1 evaluation criteria.

Objective This study aimed to investigate the antimicrobial resistance profiles of bacterial strains isolated from pediatric intensive care units(PICU)in China for better antimicrobial therapy.Methods Clinical isolates were collected from 17 institutions,including tertiary care children's hospitals and pediatric department of tertiary general hospitals in China from January 1,2020 to December 31,2022.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were interpreted according to the breakpoints released by the Clinical and Laboratory Standards Institute(CLSI)in 2020.Results A total of 10 688 isolates were collected,including gram-positive organisms(39.2％)and gram-negative organisms(60.8％).The top three organisms were S.aureus(13.6％,1 453/10 688),A.baumannii(10.0％,1 067/10 688),and coagulase-negative Staphylococcus(9.9％,1 058/10 688).Multi-drug resistant organisms(MDROs)were very common in children.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-resistant Enterobacterales(CRE),carbapenem-resistant E.coli,carbapenem-resistant K.pneumoniae(CRKP),carbapenem-resistant A.baumannii(CRAB),and carbapenem-resistant P.aeruginosa(CRPA)was 41.1％,19.4％,8.8％,30.9％,67.4％,and 28.8％,respectively.Overall,more than 50％of Enterobacteriales isolates were resistant to cephalosporins,while nearly 25％of Enterobacteriales isolates were resistant to carbapenems.MDROs were highly resistant to commonly used antibiotics.More than 80％of CRE and CRAB strains were resistant to all beta-lactam antibiotics.CRE and CRAB showed low resistance rates to tigecycline and polymyxin.CRPA showed lower resistance rates to piperacillin,beta-lactamase inhibitor combinations than the resistance rates to third and fourth generation cephalosporins.All of the Staphylococcus and Enterococcus isolates were susceptible to vancomycin and tigecycline.None of PRSP strains isolated from meningitis and nonmeningitis samples were resistant to rifampicin,vancomycin,or linezolid.The prevalence of β-lactamase-negative ampicillin-resistant(BLNAR)strains was 43.3％in Haemophilus influenzae.Conclusions MDROs were prevalent in PICU.It is necessary to establish an effective multidisciplinary team(MDT)to control the antimicrobial resistance.

Objective:To compare the efficacy of different doses of tranexamic acid (TXA) for traumatic hemorrhagic shock (THS) in the early phase of trauma following acute exposure to high altitude in rabbits.Methods:Twenty-five healthy male New Zealand rabbits were randomly divided into plain control group ( n=5) and acute high-altitude THS group ( n=20) according to the random number table method. The plain control group did not undergo THS modeling throughout the experiment while the acute high-altitude THS group was raised in a hypoxia simulation chamber with a volume fraction of 10% for 3 days to establish the THS model. Based on the different doses of TXA administered intravenously at 30 minutes after THS modeling, the acute high-altitude THS group was further divided into four subgroups: acute high-altitude THS+0 mg/kg TXA subgroup, acute high-altitude THS+45 mg/kg TXA subgroup, acute high-altitude THS+90 mg/kg TXA subgroup and acute high-altitude THS+135 mg/kg TXA subgroup, with 5 rabbits in each. The vital signs [mean arterial pressure (MAP), heart rate, rectal temperature] and blood cell counts [red blood cell count (RBC), platelet count (PLT)], 4 coagulation parameters [fibrinogen (FIB), D-dimer, activated partial thromboplastin time (APTT), prothrombin time (PT)], thromboelastography [clotting reaction time (R value), clot formation time (K value), maximum amplitude (MA value)], syndecan-1, inflammatory factors [interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α)], and plasminogen activator inhibitor-1 (PAI-1) were recorded before blood loss, at 30 minutes and 120 minutes after blood loss. At 6 hours after THS, the lungs, terminal ileum, and kidneys of the rabbits were collected to observe tissue damage, and the wet/dry weight ratio (W/D) and total water content (TLW) of the lung tissue were measured. Results:(1) Vital signs: Before blood loss, there were no significant differences in MAP, heart rate, or rectal temperature between the acute high-altitude THS subgroups and the plain control group ( P>0.05). At 30 minutes and 120 minutes after blood loss, the acute high-altitude THS subgroups exhibited significantly lower MAP, heart rate, and rectal temperature compared to those in the plain control group ( P<0.05). No significant differences were observed in MAP, heart rate or rectal temperature among the acute high-altitude THS subgroups at any time point ( P>0.05). In the acute high-altitude THS subgroups, MAP, heart rate and rectal temperature were significantly decreased at 30 minutes and 120 minutes after blood loss compared to those before blood loss ( P<0.05); At 120 minutes after blood loss, these parameters were further significantly decreased compared to those at 30 minutes after blood loss ( P<0.05). (2) Blood cell counts: Before blood loss, the RBC count was significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while the PLT was significantly lower ( P<0.05). At 30 minutes after blood loss, there was no significant difference in RBC count between the acute high-altitude THS subgroups and the plain control group ( P>0.05), but the PLT remained significantly lower in the acute high-altitude THS subgroups ( P<0.05). At 120 minutes after blood loss, the RBC count was significantly lower in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), with no significant differences among the acute high-altitude THS subgroups ( P>0.05). The PLT count was significantly lower in the acute high-altitude THS+0 mg/kg TXA subgroup compared to the other subgroups ( P<0.05). The PLT count in the acute high-altitude THS+45 mg/kg TXA subgroup was significantly lower than those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with no significant differences between the latter two subgroups ( P>0.05). (3) Four Coagulation parameters: Before blood loss, D-dimer level was significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while no significant difference was observed in FIB ( P>0.05). APTT and PT were significantly shortened in the acute high-altitude THS subgroups ( P<0.05). At 30 minutes after blood loss, D-dimer level remained significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while FIB was significantly lower ( P<0.05), with significant increase of APTT and PT compared to those before blood loss ( P<0.05). At 120 minutes after blood loss, the acute high-altitude THS+0 mg/kg TXA subgroup exhibited significantly higher D-dimer level compared to the other subgroups ( P<0.05), with significantly lower FIB and higher APTT and PT ( P<0.05). The acute high-altitude THS+45 mg/kg TXA subgroup also showed significantly higher D-dimer level compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with significantly lower FIB and increased APTT and PT ( P<0.05). No significant differences were observed in D-dimer, FIB, APTT or PT between the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P>0.05). (4) Thromboelastography parameters: Before blood loss, the R value was significantly shorter in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while no significant differences were observed in K value or MA value ( P>0.05). At 30 minutes after blood loss, both R value and K value were significantly shorter in the acute high-altitude THS subgroups compared to those in the plain control group ( P<0.05), with no significant differences in MA value ( P>0.05). At 120 minutes after blood loss, the acute high-altitude THS+0 mg/kg TXA subgroup exhibited significantly increased R value and K value compared to those in the other subgroups ( P<0.05), while MA value was significantly decreased ( P<0.05). The remaining acute high-altitude THS subgroups showed significant decrease of R value and K value compared to those in the plain control group ( P<0.05), while MA value was significantly lower ( P<0.05). The acute high-altitude THS+45 mg/kg TXA subgroup exhibited significantly lower R value and K value compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with no significant differences in R value, K value and MA value between the later two groups ( P<0.05). (5) Changes in Syndecan-1, inflammatory factors and PAI-1: Before blood loss, syndecan-1 was significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while no significant differences were observed in IL-6, TNF-α, or PAI-1 ( P>0.05). At 30 minutes after blood loss, syndecan-1, IL-6, TNF-α, and PAI-1 were significantly higher in the acute high-altitude THS subgroups compared to those in the plain control group ( P<0.05). At 120 minutes after blood loss, syndecan-1, IL-6, TNF-α, and PAI-1 were significantly higher in the acute high-altitude THS subgroups compared to those in the plain control group ( P<0.05). Among them, the acute high-altitude THS+0 mg/kg TXA group exhibited significantly higher levels of syndecan-1, IL-6, TNF-α, and PAI-1 compared to the other acute high-altitude THS subgroups ( P<0.05). The acute high-altitude THS+45 mg/kg TXA subgroup had significantly higher syndecan-1, IL-6, and TNF-α compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with no significant difference in PAI-1 ( P>0.05). No significant differences were observed in syndecan-1, IL-6, TNF-α or PAI-1 between the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P>0.05). (6) Tissue injury: At 6 hours after THS, acute high-altitude THS+0 mg/kg TXA group exhibited significant interstitial thickening of the lung with extensive inflammatory cell infiltration, localized loss of intestinal brush border accompanied by cellular disruption, and marked structural disruption of renal corpuscles with focal cellular injury and necrosis. At 6 hours after THS, the acute high-altitude THS+0 mg/kg TXA subgroup exhibited significantly higher lung injury scores, Chiu′s intestinal injury scores, and kidney injury scores compared to those of the other subgroups ( P<0.05). No significant differences were observed in the tissue injury scores of the lungs, intestines and kidneys among the other subgroups ( P>0.05). The acute high-altitude THS+0 mg/kg TXA subgroup also had significantly higher lung W/D and TLW compared to those in the other subgroups ( P<0.05). At 6 hours after THS, the acute high-altitude THS+45 mg/kg TXA group exhibited significantly higher W/D and TLW of the lung tissues compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA groups ( P<0.05), with no significant differences between the latter two subgroups ( P>0.05). Conclusions:At 3 days after acute exposure to high altitude, rabbits show a hypercoagulable state of the blood, accompanied by endothelial barrier dysfunction. At 30 minutes after the induction of acute high-altitude THS, a single slow intravenous bolus injection of TXA at doses of 90 mg/kg and 135 mg/kg is more effective in improving coagulation and fibrinolysis function, inflammatory response, endothelial injury, and reduced the risk of pulmonary edema than that at a dose of 45 mg/kg.

Objective:To investigate the clinical management,complications,and prognostic prediction model of bronchopulmonary dysplasia(BPD)in preterm infants.Methods:A total of 854 very preterm infants(gestational age ≤ 32 weeks)admitted to the Neonatal Intensive Care Unit(NICU)of Shanghai Children's Hospital from January 2018 to December 2022 were retrospectively enrolled.After applying inclusion and exclusion criteria,713 infants were included.Based on the 2018 National Institute of Child Health and Human Development(NICHD)diagnostic criteria for BPD,the cohort was divided into a BPD group(n=164)and a non-BPD group(n=549).Clinical data of infants and maternal characteristics were compared between groups.Univariate and stepwise multivariate logistic regression analyses were performed to identify independent risk factors for BPD and evaluate clinical management.A nomogram model was subsequently developed to predict BPD prognosis.Results:Gestational age,duration of non-invasive ventilation,total oxygen therapy time,total hospital stay,hemodynamically significant patent ductus arteriosus(hsPDA),maximum diameter of patent ductus arteriosus(PDA),fetal growth restriction(FGR),use of vasoactive agents,and proportion of pulmonary surfactant administration were identified as independent risk factors for BPD(all P＜0.05,OR＞0).The nomogram model demonstrated excellent predictive performance,with an area under the receiver operating characteristic curve(AUC)of 0.93 and a calibration curve slope approaching 1.The Hosmer-Lemeshow goodness-of-fit test indicated satisfactory model calibration(x2=8.2865,P=0.406).Conclusion:Gestational age,non-invasive ventilation duration,total oxygen therapy time,total hospital stay,hsPDA,PDA maximum diameter,FGR,vasoactive agents,and pulmonary surfactant use are critical predictors of BPD in preterm infants.The prognostic models for BPD incidence and severity,constructed based on these factors,exhibit strong predictive accuracy and may serve as a valuable clinical tool for risk stratification and early intervention.

Objective:To compare the efficacy of different doses of tranexamic acid (TXA) for traumatic hemorrhagic shock (THS) in the early phase of trauma following acute exposure to high altitude in rabbits.Methods:Twenty-five healthy male New Zealand rabbits were randomly divided into plain control group ( n=5) and acute high-altitude THS group ( n=20) according to the random number table method. The plain control group did not undergo THS modeling throughout the experiment while the acute high-altitude THS group was raised in a hypoxia simulation chamber with a volume fraction of 10% for 3 days to establish the THS model. Based on the different doses of TXA administered intravenously at 30 minutes after THS modeling, the acute high-altitude THS group was further divided into four subgroups: acute high-altitude THS+0 mg/kg TXA subgroup, acute high-altitude THS+45 mg/kg TXA subgroup, acute high-altitude THS+90 mg/kg TXA subgroup and acute high-altitude THS+135 mg/kg TXA subgroup, with 5 rabbits in each. The vital signs [mean arterial pressure (MAP), heart rate, rectal temperature] and blood cell counts [red blood cell count (RBC), platelet count (PLT)], 4 coagulation parameters [fibrinogen (FIB), D-dimer, activated partial thromboplastin time (APTT), prothrombin time (PT)], thromboelastography [clotting reaction time (R value), clot formation time (K value), maximum amplitude (MA value)], syndecan-1, inflammatory factors [interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α)], and plasminogen activator inhibitor-1 (PAI-1) were recorded before blood loss, at 30 minutes and 120 minutes after blood loss. At 6 hours after THS, the lungs, terminal ileum, and kidneys of the rabbits were collected to observe tissue damage, and the wet/dry weight ratio (W/D) and total water content (TLW) of the lung tissue were measured. Results:(1) Vital signs: Before blood loss, there were no significant differences in MAP, heart rate, or rectal temperature between the acute high-altitude THS subgroups and the plain control group ( P>0.05). At 30 minutes and 120 minutes after blood loss, the acute high-altitude THS subgroups exhibited significantly lower MAP, heart rate, and rectal temperature compared to those in the plain control group ( P<0.05). No significant differences were observed in MAP, heart rate or rectal temperature among the acute high-altitude THS subgroups at any time point ( P>0.05). In the acute high-altitude THS subgroups, MAP, heart rate and rectal temperature were significantly decreased at 30 minutes and 120 minutes after blood loss compared to those before blood loss ( P<0.05); At 120 minutes after blood loss, these parameters were further significantly decreased compared to those at 30 minutes after blood loss ( P<0.05). (2) Blood cell counts: Before blood loss, the RBC count was significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while the PLT was significantly lower ( P<0.05). At 30 minutes after blood loss, there was no significant difference in RBC count between the acute high-altitude THS subgroups and the plain control group ( P>0.05), but the PLT remained significantly lower in the acute high-altitude THS subgroups ( P<0.05). At 120 minutes after blood loss, the RBC count was significantly lower in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), with no significant differences among the acute high-altitude THS subgroups ( P>0.05). The PLT count was significantly lower in the acute high-altitude THS+0 mg/kg TXA subgroup compared to the other subgroups ( P<0.05). The PLT count in the acute high-altitude THS+45 mg/kg TXA subgroup was significantly lower than those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with no significant differences between the latter two subgroups ( P>0.05). (3) Four Coagulation parameters: Before blood loss, D-dimer level was significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while no significant difference was observed in FIB ( P>0.05). APTT and PT were significantly shortened in the acute high-altitude THS subgroups ( P<0.05). At 30 minutes after blood loss, D-dimer level remained significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while FIB was significantly lower ( P<0.05), with significant increase of APTT and PT compared to those before blood loss ( P<0.05). At 120 minutes after blood loss, the acute high-altitude THS+0 mg/kg TXA subgroup exhibited significantly higher D-dimer level compared to the other subgroups ( P<0.05), with significantly lower FIB and higher APTT and PT ( P<0.05). The acute high-altitude THS+45 mg/kg TXA subgroup also showed significantly higher D-dimer level compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with significantly lower FIB and increased APTT and PT ( P<0.05). No significant differences were observed in D-dimer, FIB, APTT or PT between the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P>0.05). (4) Thromboelastography parameters: Before blood loss, the R value was significantly shorter in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while no significant differences were observed in K value or MA value ( P>0.05). At 30 minutes after blood loss, both R value and K value were significantly shorter in the acute high-altitude THS subgroups compared to those in the plain control group ( P<0.05), with no significant differences in MA value ( P>0.05). At 120 minutes after blood loss, the acute high-altitude THS+0 mg/kg TXA subgroup exhibited significantly increased R value and K value compared to those in the other subgroups ( P<0.05), while MA value was significantly decreased ( P<0.05). The remaining acute high-altitude THS subgroups showed significant decrease of R value and K value compared to those in the plain control group ( P<0.05), while MA value was significantly lower ( P<0.05). The acute high-altitude THS+45 mg/kg TXA subgroup exhibited significantly lower R value and K value compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with no significant differences in R value, K value and MA value between the later two groups ( P<0.05). (5) Changes in Syndecan-1, inflammatory factors and PAI-1: Before blood loss, syndecan-1 was significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while no significant differences were observed in IL-6, TNF-α, or PAI-1 ( P>0.05). At 30 minutes after blood loss, syndecan-1, IL-6, TNF-α, and PAI-1 were significantly higher in the acute high-altitude THS subgroups compared to those in the plain control group ( P<0.05). At 120 minutes after blood loss, syndecan-1, IL-6, TNF-α, and PAI-1 were significantly higher in the acute high-altitude THS subgroups compared to those in the plain control group ( P<0.05). Among them, the acute high-altitude THS+0 mg/kg TXA group exhibited significantly higher levels of syndecan-1, IL-6, TNF-α, and PAI-1 compared to the other acute high-altitude THS subgroups ( P<0.05). The acute high-altitude THS+45 mg/kg TXA subgroup had significantly higher syndecan-1, IL-6, and TNF-α compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with no significant difference in PAI-1 ( P>0.05). No significant differences were observed in syndecan-1, IL-6, TNF-α or PAI-1 between the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P>0.05). (6) Tissue injury: At 6 hours after THS, acute high-altitude THS+0 mg/kg TXA group exhibited significant interstitial thickening of the lung with extensive inflammatory cell infiltration, localized loss of intestinal brush border accompanied by cellular disruption, and marked structural disruption of renal corpuscles with focal cellular injury and necrosis. At 6 hours after THS, the acute high-altitude THS+0 mg/kg TXA subgroup exhibited significantly higher lung injury scores, Chiu′s intestinal injury scores, and kidney injury scores compared to those of the other subgroups ( P<0.05). No significant differences were observed in the tissue injury scores of the lungs, intestines and kidneys among the other subgroups ( P>0.05). The acute high-altitude THS+0 mg/kg TXA subgroup also had significantly higher lung W/D and TLW compared to those in the other subgroups ( P<0.05). At 6 hours after THS, the acute high-altitude THS+45 mg/kg TXA group exhibited significantly higher W/D and TLW of the lung tissues compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA groups ( P<0.05), with no significant differences between the latter two subgroups ( P>0.05). Conclusions:At 3 days after acute exposure to high altitude, rabbits show a hypercoagulable state of the blood, accompanied by endothelial barrier dysfunction. At 30 minutes after the induction of acute high-altitude THS, a single slow intravenous bolus injection of TXA at doses of 90 mg/kg and 135 mg/kg is more effective in improving coagulation and fibrinolysis function, inflammatory response, endothelial injury, and reduced the risk of pulmonary edema than that at a dose of 45 mg/kg.