Which of the following is not a purpose of access sheaths?

Access sheaths are primarily designed to facilitate various procedures in interventional radiology by providing a stable and consistent route for instruments to enter the vascular system.

The purpose of access sheaths includes reducing vessel trauma, which they achieve by minimizing the need for repeated punctures in the same location. They help facilitate the insertion and withdrawal of equipment, making procedures smoother and more efficient. Additionally, access sheaths are instrumental in maintaining access to the vascular system over time, allowing multiple exchanges of devices without needing to reinject or puncture the blood vessel repeatedly.

However, access sheaths are not intended to serve as a permanent access point. While they allow for temporary access during a procedure, they are typically removed once the procedure is complete. Permanent access points are usually established using different techniques, such as implanted ports or fistulas, that are designed to remain in place for long-term applications. Therefore, the idea of using access sheaths as a means of providing a permanent access point does not align with their design or purpose in interventional procedures.