The purpose of this study is to compare a new intracavitary ECG guiding method for real-time positioning the tip of three-way valve type peripherally inserted central catheters versus conventional surface prediction length method in terms of single-time target rate.

The use of peripherally inserted central catheters (PICCs) has increased significantly for cancer patients receiving chemotherapy. For these patients, PICCs afford many advantages with regards to complications and treatment convenience.

Current practice utilizes the estimated length of the catheter from puncture site to the junction of superior vena cava / right atrium (SVC-RA) for guiding tip placement. Next the catheter tip placement was confirmed by radiographic imaging prior to use of the line for administration of chemotherapy medications. In this case, the catheter is often mal-positioned and requires adjustment and repeat radiographic imaging in order to ensure proper placement, ideally at the SVC-RA junction. These potentially additional procedures are time-consuming and also expose patients, nurses and physicians to radiations.

Intracavitary electrocardiogram with an electrode placed inside the catheter during insertion has shown identifiable changes in P-wave, which are sufficient to guide PICC tip placement. Moreover, less procedural time and radiation are expected.

This study aims to demonstrate if this intracavitary electrocardiogram guided method is superior to conventional surface prediction length method in terms of single-time target rate of correct tip placement. In addition, we would like to investigate symptomatic thrombosis incidence and its risk factors after three-valve PICC implanted among patients with malignant tumors; to clarify procedure time used and cost of the new intracavitary ECG guiding method and to explore the maximal P-wave amplitude of intracavity ECG real-time positioning technology and its predictive factors.

Inclusion Criteria:

1. Patients with malignant tumors who will require periodical infusion of chemotherapy drugs using three-valve PICC;

2. Aged >18 to < 80 years old;

3. Baseline ECG records prior to PICC catheter showed normal P wave;

4. Agreed to participate in this study, and signed PICC informed consent.

   Exclusion Criteria:

5. Patients with heart diseases, such as valvular heart disease, atrial fibrillation, supraventricular tachycardia, pulmonary heart disease or having a pacemaker and post cardiac surgery which may affect P waves.

6. Patients unable to lie in the prostrate or semi-supine position.