This study was designed as a prospective, multicenter, randomized controlled study, with the incidence of postoperative complications as the main observation end point. It was a superiority design.The purpose of this study was to compare the incidence of complications associated with EDUG-guided subcutaneous tunneling and conventional puncture after peripheral vein placement of PICCs

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.