There are times that a patient needs a PICC placed in an arm with an existing arterial line in place. Has there been any research on this topic? Most of us do vein assessment without tourniquets but we do use one for the brief time we need to access the vein. We PICC in teams of 2 so our circulating RN will tie the tourniquet just before the inserting RN is ready to stick and the the tourniquet is released as soon as the wire is threaded successfully. Our concern, besides the effect we have on the wave form and possibly rendering the A-line useless is the potential future issues we may be causing for the patients. Does anyone have any information we can use to ensure our patients' well-being?