经颈内静脉置入中心静脉导管术中腔内心电图P波波形改变及临床意义

目的：通过分析颈内静脉中心静脉置管术中腔内心电图的P波变化特点,探讨心电图辅助技术在中心静脉置管术中的临床应用价值。方法2013年8月至12月共876例行颈内静脉中心静脉置管肿瘤患者参与本研究。全部患者均在B超引导下穿刺置管,术中采用腔内心电监测技术引导送管,最终导管留置长度以“Peres’ formula”定位身高长度为准,术后行导管尖端位置X线定位。对腔内心电图P波特征性改变包括P波振幅升高、双相P波及双峰P波获得情况进行分析。结果876例患者置管过程中腔内心电图P波振幅升高率、双向P波和双峰P波获得率分别为94．2%、17．5%和54．6%,特征性P波获得率即获得P波振幅升高、双向P波或双峰P波其中任意一项的比例为97．8%。在P波振幅增高的825例中,置管到位时振幅增加值平均为（4．2±2．6）mv,其中62．8%的患者在送管至“Peres’fomula”定位长度时出现最高振幅P波,其余37．2%均提前出现最高P波；送管到位时P波的振幅与R波振幅之比P 50为0．4。结论不推荐将腔内心电监测技术作为X线诊断的替代方案用于中心静脉导管尖端位置的判断标准。但该技术在置管操作中对帮助判断导管异位具有重要临床价值,且经济、便捷、适用性强,可作为颈内静脉置管中一项重要的辅助技术应用。

The Changes and the Role of Intracavitary electrocardiogram P Waves During the Internal Jugular Vein Catheterization

Objective To analyze the changes of P wave of intracavitary electrocardiogram during the internal jugular vein cauterization and to explore the clinic value of this technique. Methods 876 central catheters were inserted in the internal jugular veins under intracavitary electrocardiogram-guided technique from August 2013 to December 2013. All the puncture was guided by B ultrasonic, and the catheterization was under the guide of intracavitary electrocardiogram. The length of catheters in the body was according to the Peres’ formula. All the 876 patients were received the examination of X-ray. Then the changes of P-waves’ amplitude, the proportion of diphasic P waves and the double peak of P waves were analyzed. Results When the catheters were in the superior vena cava,94. 2% patients’ P waves amplitude raised. The double peak of P waves and diphasic P waves acquired took part in 54. 6% and 17. 5% respectively. The average amplitude arise was（4. 2 ± 2. 6）mv when the catheter tips in the lower 1/3 of superior vena cava or at the superior vena cavaright atrium junction（the target location）. In 62. 8% patients, the highest P waves were acquired when the length of catheters in the body exactly matched the predictable length Peres′formuld. The other 37. 2% cases’ highest P waves appeared before the catheters arrived at the target location. When the catheter tip was at the target location, the P wave amplitude-to-R wave amplitude ratio was 0. 4. Conclusion We recommended against using intracavitary electrocardiogram technique instead of X-ray in the determination of catheter tips. The intracavitary electrocardiogram technique played an important role in avoiding catheter tip malposition. Application of intracavitary electrocardiogram placement performed during insertion was low cost, convenient, easily duplicated and saving time required for tip repositioning of malpositioned tips found after the end of the procedure. The intracavitary electrocardiogram technique was a useful ssistive technology in the internal jugular vein catheterization.