Short PIVC (intravenous indentation needle) accounts for more than 50% of clinical infusion tools, but long PIVC is rarely used and studied in China. This study aims to explore the application characteristics and application effects of long PIVC in China. It provides reference for the correct selection of infusion tools, and promotes the clinical application and promotion of new intravenous therapy tools.

The study nurse will work with the responsible physician to assess the eligibility for enrollment and sign the informed consent. Were randomly assigned to the control group (to receive a new 24G/22G (0.7mm*19mm/0.9mm*25mm) short PIVC (closed needle protected venous catheter system) puncture) or the intervention group (to insert a new 3F (8cm) or 4F(10cm) long PIVC) for daily routine maintenance until catheter removal, General demographic data, laboratory-related data, catheter-related data, catheter-related complications (unplanned extubation, phlebitis, catheter blockage, catheter-related thrombosis, catheter-related bloodstream infection, exudation, etc.) and patient satisfaction were collected.

The control group will receive a new 24G or 22G short peripheral venous catheter for puncture using direct view aseptic technique, while the intervention group will be implanted with a new long peripheral venous catheter selected by the puncture operator using aseptic technique depending on the puncture location and venous conditions. After successful puncture, blood was returned in both groups and easily washed with 0.9% sodium chloride solution. The catheter was considered to be placed in the correct position and could be used normally. Intravenous infusion therapy should be started immediately after successful catheterization. The catheter should be checked at least 3 times a day and washed with 10 ml.9% sodium chloride solution before each intravenous therapy. After disconnection of any infusion, pulse flushing with 0.9% sodium chloride solution 10ml and positive pressure sealing tube flushing to seal the catheter. Patient information was collected during the study, including sociodemographic information, duration of intravenous therapy, and details about catheter failure.

Inclusion Criteria:

1. A male or female aged 18 years or older who is able and willing to give written informed consent;
2. Identification of the patient's medical diagnosis based on the competent physician and the study nurse at any time during the hospital stay, and judgment that the duration of peripheral intravenous infusion therapy needs to exceed 4 days;
3. Subjects with good compliance and can cooperate with catheter maintenance and observation.

Exclusion Criteria:

1. Patients who are delirious and unable to cooperate;
2. Patients requiring central venous access;
3. Patients suffering from connective tissue diseases or blood diseases;
4. Patients allergic to catheters or dressings;
5. any subject in a condition deemed by the investigator to interfere with the evaluation of results or pose a health risk to the subject.