Once the PICC line is in and will remain in place for several months, since it is clearly something that you want on your body and it is difficult to remove/replace it, you are halachically permitted to immerse with it.
Often, the PICC is held in place with adhesive ‘wings’ that are changed regularly by a nurse. It is preferable to remove the wings before immersing. If that is not possible, you may immerse with the wings (taking care to clean around them) but should not have the wings changed until seven days after immersion.
Unfortunately, immersion with a PICC line can present medical problems for some patients. Please ask your physician directly whether a single brief immersion in clean, chlorinated water would be acceptable, and how it could be handled. You may wish to refer to our article on Mikveh Immersion in the Immunocompromised Host in the section of our website designed for medical professionals.
Please feel free to get back to us with any further questions.
Refuah Shleimah!