Objective: To identify risk factors for infusion-related phlebitis with peripheral intravenous catheters. Design: A randomized trial of two catheter materials, with consideration of 21 potential risk factors. Setting: A university hospital. Patients: Hospitalized adults without granulocytopenia who received a peripheral intravenous catheter. Interventions: House officers or ward nurses inserted the catheters, and each insertion was randomized to a catheter made of tetrafluoroethylene-hexafluoropropylene (FEP-Teflon) or a novel polyetherurethane without leachable additives (PEU-Vialon). Measurements: Research nurses scored insertion sites each day for inflammation and cultured catheters at removal. Results: The Kaplan-Meier risk for phlebitis exceeded 50% by day 4 after catheterization. Intravenous antibiotics (relative risk, 2.00), female sex (relative risk, 1.88), prolonged (> 48 hours) catheterization(relative risk, 1.79), and catheter material (PEU-Vialon: FEP-Teflon) (relative risk, 0.73) strongly predicted phlebitis in a Cox proportional hazards model (each, P < 0.003). The best-fit model for severe phlebitis identified the same predictors plus catheter-related infection (relative risk, 6.19), phlebitis with a previous catheter (relative risk, 1.54), and anatomic site (hand: forearm, relative risk, 0.71; wrist:forearm, relative risk, 0.60). The low incidence of local catheter-related infection was comparable wwith the two catheter materials (5.4% [95% CI, 3.8% to 7.6%] and 6.9% [CI, 4.9% to 9.6%]); none of the 1054 catheters prospectively studied caused bacteremia. Conclusions: Multiple factors, including the infusate and the duration of cannulation, contribute to the development of infusion-related phlebitis. The use of peripheral intravenous catheters made of PEU-Vialon appears to pose the same risk for catheter-related infection as the use of catheters made of FEP-Teflon, and PEU-Vialon can permit longer cannulation with less risk for phlebitis. The risk for catheter-related bacteremia with FEP-Teflon and PEU-Vialon catheters is sufficiently low that it no longer seems justifiable to recommend the use of small steel needles for most peripheral intravenous therapy.
