To report the success rate and complications associated with peripherally inserted central venous catheters (PICCs) and to compare costs between PICCs and centrally inserted central catheters.We undertook a cohort study of the first 1,000 patients referred to the PICC service of a large tertiary-care, university-affiliated, community hospital. The data were analyzed for insertion success rate, insertion mode, complication rate, successful completion, insertion costs, and applicability of PICCs in "high-risk" groups (transplant, human immunodeficiency virus-infected, intensive-care unit, and pediatric populations).Of 1,000 consecutive PICC attempts, 963 (96.3%) were successful. Cutdown procedures were necessary in 141 insertions (14.6%). Complications of PICC placement occurred in 170 cases (17.7%). Among the major complications were a need for multiple attempts at insertion in 92 cases, malpositioning in 56, mechanical phlebitis in 37, clotting in 37, and bleeding in 5. The rate for completion of therapy was 68.9%. Frequent reasons for early termination were dislodgment (in 85 cases) and infection (in 72-37 confirmed and 35 potential cases). The rate of confirmed infection was 11 per 10,000 catheter days. The costs of PICC insertion were less than those associated with centrally inserted central catheters.PICCs can satisfy long-term vascular needs and are safe in many patient populations. The infection rate did not depend on insertion mode, lumen number, or patient's immune status. Use of total parenteral nutrition was the most important risk factor in all patient subsets. Cost and safety considerations strongly favor PICCs as alternatives to other vascular access devices.