ABSTRACT
Objective To determine the accuracy of intracavitary electrocardiogram bimodal P-wave and characteristic P-wave in the position of PICC tip. Methods In the process of ECG guided catheterization, the morphological changes of P-wave in the intracavitary electrocardiogram were observed, and the bimodal P-wave and characteristic P-wave were recorded. The corresponding catheter length of the bimodal P-wave and characteristic P-wave were recorded. CT three-dimensional reconstruction was performed on 416 patients who underwent CT examination before and after catheterization. The distance between carina of trachea to superior vena cava and the right atrium junction was measured as best position of PICC and the standard distance. After catheterization, the distance from the tip of catheter to the corresponding catheter length of the bimodal P-wave and characteristic P-wave was measured as actual distance, and compared with the standard distance. Results In 416 cases, 168 patients (40.38％) were bimodal P-wave, and the accurate rate of bimodal P-wave was 86.31％(145/416), and the accurate rate of the characteristic P-wave was 13.69％(23/416). The standard distance was (41.96 ± 9.16) mm, the actual distance of corresponding characteristic P-wave was (48.00±15.18) mm and bimodal P-wave was (45.10± 11.16) mm. The distance of bimodal P-wave to control was (1.31±0.33) mm and characteristic P-wave was (6.00 ± 2.88) mm, which was significant statistical difference (t =5.197, P < 0.05), and the standard deviation of the distance of bimodal P-wave to control was smaller (0.33 < 2.88). Conclusions The intracavitary electrocardiogram bimodal P-wave is more accurate than characteristic P-wave in the position of PICC tip and it supplements and improves thePICC's tip position.