Visualization technology is more and more widely used in clinical anesthesia.Nerve block in pediatric anesthesia assisted by visual technique of ultrasound not only achieved the similar curative effect as traditional blind operation but also had lower incidence of complications,so this technology is more and more useful in pediatric anesthesia.This article reviewed the progress of the application of ultrasound guided nerve block in pediatric anesthesia.

From October 2014 to June 2015, among 5 800 pediatric patients underwent outpatient sedation in MRI and Special Inspection Departments at our hospital, the incidence of sedation-related ad-verse events was 272%(158 cases), and the mortality rate was 003%(2 cases)in pediatric outpa-tients. The common adverse events were nausea and vomiting(constituent ratio 3214%), regurgitation and aspiration(constituent ratio 2443%), respiratory depression(constituent ratio 2928%), agitation (constituent ratio 1571%)and delayed recovery(constituent ratio 143%). When chloral hydrate was used for sedation, it should be mixed with sugar to prevent the occurrence of nausea and vomiting; young age(especially preterm infant), diseases of respiratory system or nervous system and congenital heart dis-ease were the possible inducements to sedation-related adverse events, and intervention strategy should be performed to decrease the occurrence of adverse events and to improve the quality of sedation in pediatric outpatients.

Objective To evaluate the efficacy of Arndt endobronchial blocker (AEB) for airway management during one-lung ventilation (OLV) in pediatric patients.Methods Thirty pediatric patients,aged 4 months-12 yr,weighing 5.6-26.0 kg,of American Society of Anesthesiologists physical status Ⅱ-Ⅳ,scheduled for elective thoracotomy under OLV requiring the use of single lumen tracheal tube assisted by AEB,were enrolled in this study.OLV was performed with the AEB placed outside the single lumen tracheal tube in pediatric patients below 2 years old and with AEB inserted through the single lumen tracheal tube in pediatric patients ≥ 2 years old.The rate of successful establishment of artificial airway at first attempt,time of establishing artificial airway,time of pulmonary collapse,AEB malpositions and airway pressure before and after OLV were recorded,and the efficacy of lung collapse was evaluated.Results The rate of successful tracheal intubation of extraluminal and endoluminal AEB placement at first attempt was 100％ in 30 pediatric patients,and no high airway pressure was found after OLV.The efficacy of lung collapse was poor in one patient and good in one patient,and intraoperative AEB malpositions were found in two patients among the pediatric patients used extraluminal AEB placement.The efficacy of lung collapse was good in one patient,intraoperative AEB malposition was found in one patient,and SpO2 was decreased after OLV in one patient among the pediatric patients used endoluminal AEB placement.Conclusion Reasonably selecting the method of placing AEB followed by enhancing intraoperative airway management can be safely and effectively applied for OLV in pediatric patients.

Metabolic-associated fatty liver disease (MAFLD), which is previously known as non-alcoholic fatty liver disease (NAFLD), represents a major health concern worldwide with limited therapy. Here, we provide evidence that ferroptosis, a novel form of regulated cell death characterized by iron-driven lipid peroxidation, was comprehensively activated in liver tissues from MAFLD patients. The canonical-GPX4 (cGPX4), which is the most important negative controller of ferroptosis, is downregulated at protein but not mRNA level. Interestingly, a non-canonical GPX4 transcript-variant is induced (inducible-GPX4, iGPX4) in MAFLD condition. The high fat-fructose/sucrose diet (HFFD) and methionine/choline-deficient diet (MCD)-induced MAFLD pathologies, including hepatocellular ballooning, steatohepatitis and fibrosis, were attenuated and aggravated, respectively, in cGPX4-and iGPX4-knockin mice. cGPX4 and iGPX4 isoforms also displayed opposing effects on oxidative stress and ferroptosis in hepatocytes. Knockdown of iGPX4 by siRNA alleviated lipid stress, ferroptosis and cell injury. Mechanistically, the triggered iGPX4 interacts with cGPX4 to facilitate the transformation of cGPX4 from enzymatic-active monomer to enzymatic-inactive oligomers upon lipid stress, and thus promotes ferroptosis. Co-immunoprecipitation and nano LC-MS/MS analyses confirmed the interaction between iGPX4 and cGPX4. Our results reveal a detrimental role of non-canonical GPX4 isoform in ferroptosis, and indicate selectively targeting iGPX4 may be a promising therapeutic strategy for MAFLD.