Application of IEGM guidance on preset length of PICC

Objective To explore a simple and precise method in predicting the preset length of PICC in order to improve the probability of reaching the best position in clinical practice. Methods The study investigated 419 patients who were eligible to receive PICC with IEGM guidance. The horizontal distance from the puncture point to the peak of the right collarbone sternoclavicular was reported as A length and the subsequent length into the vein was reported as B length. The P wave amplitude of lead Ⅱ began to rise and reached to 30%-50% of QRS wave, then 50%-80% of QRS wave. The two-way P wave was reported as P1, P2, P3, P4 wave and its corresponding catheter length was reported as B1, B2, B3, B4. Observing the B length with different P waves and taking X-ray in an erect position at P3 wave. In addition, the A length increased extra 7cm for patients with no P3 wave. The position of the catheter tip and the corresponding B length were the main outcomes. Results Approximately 92.36% (387/419) of the participants had typical P1, P2, P3, P4 wave and the B length were 3 cm, 5 cm, 7 cm and 10 cm (H=1 527.290, P<0.01). Approximately 97.16% (376/387) of the patients′ catheter tips were located in the third intercostal space. Approximately 7.64% (32/419) of the patients had no P3 wave and the X-ray demonstrated that 29 cases′ catheter tip was vertical downward in the third intercostal space and behind the sternum. Conclusions The method of predicting the preset length of PICC not only is simple and precise but also has a high probability of reaching the best position in clinical practice. That is, the puncture side arm abducts until vertical to the body and the horizontal distance is 7cm from the puncture point to the peak of the right collarbone sternoclavicular. Key words: Peripherally inserted central catheter; Intracardiac electrogram; Catheter length; Modified method