Have an ICU pt with existing right upper arm PICC that was placed in April. MD suspects line infection and requests PICC exchange. Of note, has DVT of left axillary vein and left IJ. Recent doppler shows new acute DVT of right axillary and right IJ. Informed MD that cannot exchange line with existing DVT. PICC exchange order cancelled but next day ordered again with the comment that the attending MD says it's ok to exchange PICC with exisiting DVT. PICC team MD director gets involved. He asks for evidence to show why it would NOT be acceptable to exhcange PICC with an existing DVT. Have been placing PICC's for 15 years and it's always been my practice not to place line with DVT. I'm surprised MD says it acceptable. Is this something new. Any help is greatly appreciated. Thank you.