Objective: To study electrocardiogram (ECG) monitoring assisted ultrasound guidance for modiifed seldinger technique (MST) in peripherally inserted central catheters (PICC) and to estimate the accuracy of ECG for presenting catheter tip location. Methods: The patients were connected with ECG monitoring system, the guide wire was connected to RA electrode in ECG monitor for leading out P wave of intracavitary ECG. The location of catheter tip was estimated by P wave characteristics and then, estimated ECG result was further compared with chest X-ray presented catheter tip position. The coherence of catheter tip position between ECG and chest X-ray was compared, the sensitivity and speciifcity of ECG estimation were calculated. Results: There were 100/104 patients showed speciifc P wave in ECG, the coherence to chest X-ray was 96.2%; 4 patients had no speciifc P wave and their chest X-ray presented that the catheter tip position at upper superior vena cava in 2 patients, at lower superior vena cava in 1 patient, at contralateral brachiocephalic vein in 1 patient. The accuracy of 2 methods had no statistic meaning. ECG estimation for PICC catheter tip position had the sensitivity at 99% and speciifcity at 100%. Conclusion: ECG monitoring may determine the catheter tip position for MST in PICC guided by ultrasound. It doesn’t need chest X-ray, without additional trauma and no radioactive contamination, which make PICC catheters get more extensive application in clinical practice.%目的：研究心电监护在辅助超声引导下改良塞丁格技术（MST）经外周中心静脉置管（PICC）并根据心电图变化判断导管末端位置的准确率。方法：104例患者连接心电监护仪，置管时利用导丝与心电监护仪RA导联相连引出腔内心电图，根据P波特征性变化对PICC导管末端位置进行判断，判断结果再与置管后根据X线胸片判断的导管末端位置结果进行比较，比较两种方法判断结果的一致性，计算心电判断法的灵敏度和特异度。结果：104例患者中有100例患者出现特征性P波，心电判断结果与X线胸片判断结果一致率为96.2%。4例未出现特征性P波的患者X线胸片显示，有2例导管末端位于上腔静脉上段、1例位于上腔静脉下端、1例位于对侧头臂静脉。两种方法的判断结果无统计学差异。灵敏度为99%，特异度为100%。结论：心电监护辅助超声引导下改良塞丁格技术PICC时可以根据心电图特征性P波对导管末端位置进行判断，而无需拍摄X线胸片，且此方法不会对患者带来额外的创伤，也无放射性污染。心电监护与临床超声引导下改良塞丁格技术PICC相结合可以使PICC得到更广泛的应用。
展开▼
