Comparing the Safety and Effectiveness of Tunnel PICC Guided by EDUG and Conventional PICC

Inclusion Criteria: * Age ≥18 years old; * Immunocompromised patients, including: ① Patients with congenital T cell/B cell deficiency or macrophage disorder; ② Patients with solid malignant tumors or hematological malignancies; ③ Patients with AIDS; ④ Patients undergoing splenectomy or solid organ transplantation; ⑤ Patients with rheumatic diseases and treated with immunomodulatory drugs; * Follow the doctor's advice to perform PICC catheterization for the first time; * No serious cardiovascular disease, such as atrial fibrillation, pulmonary heart disease, severe conduction block, etc., before catheter placement; * Patients who have not participated in other clinical studies; * Patients who voluntarily participate in the clinical study and can cooperate with the clinical follow-up. Exclusion Criteria: * Known allergy to catheter material; * History of infection, injury or radiation therapy at the puncture site; * There is a history of venous thrombosis or surgical operation at the puncture site; * Severe abnormal coagulation function; * Superior vena cava compression syndrome; * Radical mastectomy for breast cancer or axillary lymph node dissection on the operative side of the limb; * Pacemaker and arteriovenous fistula ipsilateral limb.