Objective:To explore the application value of diaphragmatic thickening fraction (DTF) and lung ultrasound score (LUS) in predicting the weaning outcome of elderly patients with acute respiratory distress syndrome (ARDS) under mechanical ventilation, and to analyze their correlation, thereby providing evidence for clinical decision-making.Methods:A retrospective analysis was conducted on elderly ARDS patients admitted to the ICU of the First Affiliated Hospital of Jinzhou Medical University from January 2020 to December 2023. The inclusion criteria included age > 60 years, endotracheal intubation, mechanical ventilation time >24 h, and a diagnosis of ARDS based on the Berlin definition. Exclusion criteria included neuromuscular diseases, spinal cord injury, post-thoracoabdominal surgery, thoracic or tracheal deformity, and mid-course tracheostomy conversion. Patients were divided into a success group and a failure group based on weaning outcomes. Demographic data, Acute Physiology and Chronic Health EvaluationⅡ (APACHEⅡ) scores, Sequential Organ Failure Assessment (SOFA) scores, oxygenation index at ICU admission, and pre-extubation DTF, LUS, and oxygenation index were recorded. Binary logistic regression analysis was used to identify independent risk factors affecting weaning outcomes. Receiver operating characteristic (ROC) curve was used to evaluate the predictive value of DTF and LUS for weaning outcomes. Pearson correlation analysis was conducted to examine the relationship between DTF and LUS.Results:A total of 317 patients were included, including 212 in the success group and 105 in the failure group. There were no statistically significant differences in gender, age, APACHEⅡ score, SOFA score, etc., between the two groups (all P>0.05). Pre-weaning LUS was higher in the failure group than in the success group [(17.26±3.04) vs. (13.69±4.06), P<0.001], and the DTF was significantly lower than that of the successful group [(27.83%±6.37%) vs. (40.15%±6.49%), P<0.001]. Binary logistic regression identified LUS and DTF as independent influencing factors for weaning outcomes (both P<0.05). ROC analysis revealed that LUS predicted weaning failure with an AUC of 0.748 (95% CI: 0.695-0.801, P<0.001), sensitivity of 83.81% and specificity of 56.60%. DTF predicted weaning success with an AUC of 0.935 (95% CI: 0.909-0.961, P<0.001), sensitivity of 83.02% and specificity of 89.52%. A negative correlation was observed between LUS and DTF before weaning ( r=-0.385, P<0.001). Conclusions:Both DTF and LUS are effective indicators for assessing weaning outcomes in elderly ARDS patients, offering complementary clinical insights. Higher LUS reflects more severe pulmonary pathology and increased weaning risk, while lower DTF indicates impaired diaphragmatic function and reduced likelihood of successful extubation. Integration of these parameters provides a comprehensive foundation for clinical decision-making.

BACKGROUNDErythropoietin (EPO) and granulocyte colony-stimulating factor (G-CSF) are both potential novel therapeutics for use after myocardial infarction (MI). However, their underlying mechanisms remain unclear and the efficacy of monotherapy with EPO or G-CSF is also controversial. Therefore, we investigated the effects of combined treatment with EPO and G-CSF on neovascularization and cardiac function in post-infarction rats and explored the potential mechanisms.

METHODSFour groups of rats were used: control (saline injection after MI, i.h.), EPO (a single dose of 5 000 IU/kg after MI, i.h.), G-CSF (a dose of 50 µg× kg(-1)× d(-1) for 5 days after MI, i.h.), and both EPO and G-CSF (EPO+G-CSF, using the same regiment as above). Cardiac function was assessed by echocardiography before and 1 day, 7 days, 14 days and 21 days after MI. CD34(+)/Flk-1(+) cells in the peripheral blood were evaluated by flow cytometry before and 3 days, 5 days and 7 days after MI. The infarct area and angiogenesis in the peri-infarct area were analyzed. The mRNA and protein expression of vascular endothelial growth factor (VEGF) and stromal-derived factor-1a (SDF-1α) in the peri-infarct area were detected by real-time quantitative RT-PCR and Western blotting.

RESULTSCompared with the control and monotherapy groups, the EPO+G-CSF group had significantly increased CD34(+)/Flk-1(+) endothelial progenitor cells (EPCs) in the peripheral blood (P < 0.05), up-regulated VEGF and SDF-1α levels in the peri-infarct region (P < 0.05), enhanced capillary density (P < 0.05), reduced infarct size (P < 0.05) and improved cardiac structure and function (P < 0.05). G-CSF alone did not dramatically increase EPCs in the peripheral blood, enhance capillary density in the peri-infarct area or reduce infarct size compared with the control group.

CONCLUSIONSCombined treatment with EPO and G-CSF increased EPCs mobilization, up-regulated VEGF and SDF-1α levels in the post-infarction microenvironment, subsequently enhanced neovascularization in the peri-infarct region and reduced infarct size. All factors contributed to its beneficial effects on cardiac function in post-infarction rats.

Animals ; Blotting, Western ; Chemokine CXCL12 ; metabolism ; Echocardiography ; Erythropoietin ; therapeutic use ; Flow Cytometry ; Granulocyte Colony-Stimulating Factor ; therapeutic use ; Male ; Myocardial Infarction ; drug therapy ; metabolism ; Neovascularization, Physiologic ; drug effects ; Rats ; Rats, Sprague-Dawley