1.Effect of heparin pretreatment on the level of neutrophil extracellular traps of serum and lung tissue in septic mice
Jing JIANG ; Shengtian MU ; Fangxiao ZHANG ; Yanting QIAO ; Yongran WU ; Zhidan ZHANG ; Xiaochun MA
Chinese Critical Care Medicine 2017;29(4):337-341
Objective To investigate the influence of heparin pretreatment on serum and lung tissue level of neutrophil extracellular traps (NETs) in septic mice model and its molecular mechanism.Methods Ninety male C57BL/6J mice were randomly divided into control group (n = 30), lipopolysaccharides (LPS) group (n = 30, 30 mg/kg LPS in 100μL normal saline was intraperitoneally injected) and LPS+heparin group (n = 30, 8 U of heparin in 20μL normal saline was subcutaneously injected 30 minutes before the injection of LPS). Six hours later of LPS injection, blood was collected and lung tissue was harvested. Enzyme linked immunosorbent assay (ELISA) was used to assess the concentration of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and histones 2AX (H2AX), neutrophil elastase (NE), which reflected NETs concentration. PicoGreen fluorescent dyes was used to detect serum circulating free DNA (cf-DNA/NETs) concentration. The protein expression levels of H2AX and NE in lung tissue were examined by Western Blot.Results The serum concentrations of TNF-α, IL-6, H2AX, NE, cf-DNA/NETs, and the protein expression levels of H2AX and NE in lung tissue of septic mice were significantly higher than those of control group [TNF-α (ng/L): 133.0±14.1 vs. 2.7±1.0, IL-6 (ng/L): 3911.2±189.2 vs. 298.9±52.5, H2AX (ng/L): 545.5±40.0 vs. 21.9±8.3, NE (μg/L): 6.48±0.12 vs. 0.47±0.15, cf-DNA/NETs (μg/L): 846.3±137.5 vs. 152.7±36.4, H2AX protein (gray value): 1.14±0.09 vs. 0.68±0.04, NE protein (gray value): 0.56±0.03 vs. 0.32±0.04, allP < 0.05]. After heparin pretreatment, levels of serum TNF-α, H2AX, NE, cf-DNA/NETs, and protein expression levels of H2AX and NE in lung tissue were significantly reduced [TNF-α (ng/L): 83.2±7.6 vs. 133.0±14.1, H2AX (ng/L): 435.0±39.0 vs. 545.5±40.0, NE (μg/L): 4.26±0.17 vs. 6.48±0.12, cf-DNA/NETs (μg/L): 606.5±73.9 vs. 846.3±137.5, H2AX protein (gray value): 0.91±0.03 vs. 1.14±0.09, NE protein (gray value): 0.42±0.03 vs. 0.56±0.03, allP < 0.05], but no significant change was found in IL-6 (ng/L: 3919.9±166.6 vs. 3911.2±189.2,P > 0.05).Conclusion Heparin pretreatment could significantly decrease the level of NETs in serum and lung tissue, and can be the potential mechanism of its organ protection in sepsis.
2.A child suffering from severe acute respiratory distress syndrome due to multiple trauma was treated with veno-veous extracorporeal membrane oxygenation with the dual lumen cannula: a case report
Yongran WU ; Yue HUI ; Wei CHEN ; Xiaojing ZOU ; Xiang ZHENG ; You SHANG
Chinese Critical Care Medicine 2022;34(10):1092-1094
Veno-veous extracorporeal membrane oxygenation (VV-ECMO) has been widely used in the treatment for severe acute respiratory distress syndrome (ARDS). Up to now, the routine access to establish VV-ECMO involves two-sites single lumen cannula via femoral vein and internal jugular venous in adult and children, while few studies about the dual lumen cannula (DLC) in VV-ECMO implemented in adult and children have been reported. On December 16, 2021, an unconscious child with severe ARDS due to multiple trauma caused by fatal falling from a height was admitted to Taihe Hospital. The initial diagnosis was hemorrhagic shock, bilateral hemopneumothorax, sternal fracture, cavity organ perforation, splenic rupture, and pelvic fracture and severe ARDS. Despite mechanical ventilation, he progressed to refractory hypoxemia and was treated with VV-ECMO after successful DLC placement in the right internal jugular vein by the mobile ECMO team of intensive care unit of the Union Hospital eventually. In addition, he received endoscopic sputum aspiration, prone position ventilation, anti-infection and nutritional treatment. His oxygenation gradually improved and he was successfully weaned from ECMO after 11 days. In this case, DLC simplified the process without any related complications, suggesting that it can be safely and effectively used in the treatment of Child's severe ARDS.