Identifying Sterile Field Contamination Actions

In this problem, we need to identify which nursing actions would contaminate a sterile field. This is a Select All That Apply question, so we must evaluate each option against the principles of surgical asepsis.

Let's evaluate the first option: placing a cotton ball dampened with sterile normal saline on the field.

A sterile field must remain dry. Moisture can cause strike-through, where microbes from the non-sterile surface underneath travel through the wet drape to the sterile side. Therefore, this action contaminates the field.

The second option says a contaminated instrument touches the outer edge of the sterile field.

While the outer one-inch edge of a sterile field is already considered contaminated, bringing a contaminated instrument into contact with any part of the field is a breach of protocol. However, since the edge is already non-sterile, this specific action is often considered redundant in terms of contamination. In clinical practice, always avoid any contact between non-sterile and sterile surfaces.

Third, dropping a sterile instrument onto the near side of the sterile field.

As long as the instrument is sterile and it lands within the sterile borders without the nurse reaching over the field, this is generally considered safe. This does not necessarily contaminate the field.