Objective:To study the clinical application of ultrasound-guided puncture and catheter tip positioning in peripherally inserted central catheter (PICC) among very/extremely low birth weight infants (VLBWI/ELBWI).Method:From January 2019 to August 2020, VLBWI/ELBWI admitted to NICU of our hospital and received PICC were prospectively enrolled in the study. Based on the last digit of medical record number was odd or even, the infants were assigned into ultrasound group and X-ray group. In the ultrasound group, puncture and catheter tip positioning were performed at bedside guided by ultrasound, while in the X-ray group, these procedures were performed empirically. The differences of catheterization procedure duration, first-time success rate, the visibility of catheter tip, primary dislocation rate, secondary dislocation rate and complication rate were compared between the two groups using SPSS 25.0.Result:A total of 118 premature infants were enrolled, including 57 cases in ultrasound group (50 cases VLBWI and 7 cases ELBWI) and 61 cases in X-ray group (54 cases VLBWI and 7 cases ELBWI). The catheterization procedure duration [(23.2±7.1) min vs. (34.1±7.5) min], first-time success rate (93.0% vs. 65.6%), the visibility of catheter tip (96.5% vs. 83.6%), primary dislocation rate (7.0% vs. 24.6%) and complication rate (7.0% vs. 21.3%) in ultrasound group were all better than X-ray group ( P<0.05). For ELBWI, the above five indexes in the ultrasound group were better than the X-ray subgroup ( P<0.05). For VLBWI, only the catheterization procedure duration and first-time success rate were better in the ultrasound group than the X-ray group ( P<0.05). Conclusion:Ultrasound-guided PICC catheterization in VLBWI/ELBWI is convenient and accurate, which can improve success rate, reduce radiation exposure and repeated catheterization injury. Timely tracking and adjustment of the catheter under ultrasound can reduce complications after catheterization. This technique is worth popularizing among VLBWI/ELBWI.

OBJECTIVE To provide reference for basic analysis of the pharmacodynamic substance in Stahlianthus involucratus. METHODS Overall 24 SD male rats were randomly divided into blank group （purified water）， and administration group （ethanol extract of S. involucratus， 15.75 g/kg， calculated by crude drug）， with 12 rats in each group. They were given drug liquid/purified water intragastrically， twice a day， every 6-8 h， for consecutive 3 days. After medication， the blood， urine and fecal samples were collected from two groups of rats. UPLC-Q-Exactive-MS technology was used to identify the chemical constituents in the ethanol extract of S. involucratus， and metabolites in the blood， urine and fecal of rats after intragastrical administration of the ethanol extract of S. involucratus. Multivariate statistical analysis was employed to screen various serum metabolites. Metabolic pathways were analyzed by MetaboAnalyst 5.0 platform. RESULTS A total of 38 chemical constituents were identified from the ethanol extract of S. involucratus， including fourteen prototype components and three metabolites identified from 5 urine samples， nine prototype components identified from fecal samples， and ten prototype components and one metabolite identified from serum samples. A total of 71 differential metabolites were screened from two groups of rat serum samples， of which 44 differential metabolites， such as ferulic acid， glycyrrhizin， were up-regulated and 27 differential metabolites， such as arachidonic acid， phenylacetylglutamine， were down-regulated. The 71 differential metabolites were mainly enriched in 11 metabolic pathways， including phenylalanine metabolism， linoleic acid metabolism， arachidonic acid metabolism， and tryptophan metabolism. CONCLUSIONS Ferulic acid， liquiritigenin， isofraxidin and formononetin may be the material basis that directly exert pharmacological effects of S. involucratus. S. involucratus may exert anti-inflammatory effects by affecting metabolic pathways， including arachidonic acid metabolism and tryptophan metabolism.