目的 比较心脏微气泡试验联合超声定位与腔内心电图定位在儿童经外周静脉置入中心静脉导管（peripherally inserted central catheter，PICC）尖端定位中的临床效果，明确微气泡技术的应用优势。 方法 采用前瞻性随机对照研究，纳入2023年8月至2024年10月某三级甲等医院小儿外科收治的152例PICC置管患儿为研究对象，采用随机数字表法将其分为试验组（微气泡联合超声实时定位）与对照组（腔内心电图定位），每组各76例。比较两组患儿定位成功率、导管尖端准确率、操作时间、并发症发生率及医疗成本。 结果 试验组在定位成功率、尖端准确率、操作效率、置管成本、家属满意度等方面均优于对照组，而机械性静脉炎、导管相关血栓、血流感染发生率以及2次摄片率方面均低于对照组，差异均有统计学意义（均P＜0.05）。 结论 心脏微气泡联合超声定位技术通过动态可视化监测可提升PICC导管定位精度，在提高操作安全性和降低并发症方面优势显著，尤其适用于需规避放射暴露的儿童群体，具有重要临床应用价值。

Objective To compare the clinical efficacy of real-time micro-bubble-enhanced ultrasound guidance versus intracavitary electrocardiogram (IC-ECG) for peripherally inserted central catheter (PICC) tip positioning in children，and to clarify the technical advantages of micro-bubble-enhanced localization.Methods A prospective randomized controlled study was conducted among 152 pediatric patients undergoing PICC placement in the Pediatric Surgery Department of a tertiary A hospital from August 2023 to October 2024.Participants were randomly assigned to the experimental group (micro-bubble-ultrasound guidance) or control group (IC-ECG guidance) with 76 patients in each group.Primary outcomes included positioning success rate，tip accuracy，procedure duration，complication rates，and medical costs were compared.Results The experimental group showed significantly superior positioning success rate，tip accuracy，and procedural efficiency，with markedly reduced incidences of mechanical phlebitis，catheter-related thrombosis，bloodstream infection and second time shooting rate.All differences were statistically significant (all P＜0.05).Conclusions Micro-bubble-enhanced ultrasound guidance improves catheter positioning accuracy through dynamic visual monitoring，demonstrating significant advantages in procedural safety and complication reduction.This radiation-free technique is particularly valuable for pediatric populations requiring avoidance of radiation exposure，highlighting its critical clinical applicability.