BACKGROUND: Peripheral arterial catheters (PACs), and their associated complications, are common in the pediatric intensive care unit (PICU). Accidental catheter displacement and non-functional PACs are the most common complications, and this may be related to inadequate catheter securement. There is mixed guidance on the best way to secure PACs to prevent complications. The authors hypothesized that sutures would not be associated with a decreased risk of malfunction or accidental removal. METHODS: This was a single center retrospective cohort study at a quaternary-care PICU. PICU patients with a peripheral arterial catheter placed in the PICU from 7/2020 to 1/2023 were included. The primary outcome was unplanned PAC removal. A univariate and multivariate Cox proportional hazards regression analysis was performed, using patient weight, sedation, paralytic, and role of the proceduralist as covariates. The secondary outcome was survival probability. A log-rank test was used to compare survival curves. RESULTS: Of 761 PACs that met inclusion criteria in 437 unique patients, 599 were sutured (78.7%) and 162 were un-sutured (21.3%). In 257 cases (33.8%), the PAC had an unplanned removal. Among all PACs, the median duration of PAC placement was 5.3 days (IQR 2.1-10.5 days). There was an unplanned removal rate of 42.2% (68) in the un-sutured group and 31.4% (188) in the sutured group ( CONCLUSIONS: Suturing is associated with fewer unplanned removals and longer catheter survival, compared to un-sutured PACs in pediatric patients.