In peripherally inserted central catheter (PICC) insertion, three-lumen variable-diameter catheters are mainly used for patients who require simultaneous multi-channel therapy (such as fluid infusion, drug administration, and monitoring) and have complex vascular conditions (such as thin or curved blood vessels). Through their "tapered" design, they can adapt to different blood vessel diameters, enabling the establishment of multi-channels with a single puncture.

The application scenarios are as follows:

Patients with Multi-Therapy Needs: 

For patients who need to infuse multiple drugs (such as antibiotics, nutritional solutions, and chemotherapeutic drugs) simultaneously and monitor central venous pressure, the three lumens provide independent channels respectively. This avoids drug interactions and eliminates the need for multiple punctures.

Patients with Poor Vascular Conditions: 

For patients with thin blood vessels, tortuous vascular courses, or poor vascular elasticity (such as the elderly, patients in the advanced stage of cancer, and long-term bedridden patients), the distal end of the catheter (the segment entering the central vein) has a larger diameter to ensure flow rate, while the proximal end (the peripheral puncture segment) has a smaller diameter. This reduces puncture difficulty and the risk of vascular injury.

Special Therapeutic Scenarios: 

For example, in intensive care unit (ICU) patients who need simultaneous fluid resuscitation, drug infusion, and vital sign monitoring, three-lumen variable-diameter catheters can meet these needs in one stop and reduce puncture-related complications (such as thrombosis and infection).