What approach is considered a type of percutaneous approach?

The placement of a catheter into an internal site is classified as a percutaneous approach because it involves accessing an internal organ or cavity through the skin or mucous membrane using a puncture or small incision, without the necessity for a large open surgery. This method is often guided by imaging techniques, allowing for minimal invasiveness and quicker recovery times.

In contrast, the other options represent different approaches or techniques. The open approach, for instance, involves making a large incision to directly access the area being treated. Excision pertains to cutting out tissue, which could be done through various methods, but typically involves more invasive procedures than a straightforward percutaneous technique. Observation does not involve any procedural intervention and is simply monitoring the patient's condition rather than treating it. Thus, placement of a catheter is the only choice that aligns directly with the definition of a percutaneous approach.