Aim of the study: Short peripheral cannula (SPC)-related phlebitis occurs in 7.5% of critically ill patients, and mechanical irritation from cannula materials is a risk factor. Softer polyurethane cannulas reportedly reduce phlebitis, but the incidence of phlebitis may vary depending on the type of polyurethane. Differences in cannula stiffness may also affect the incidence of phlebitis; however, this relationship is not well understood. This study analyzed intensive care unit (ICU) patient data to compare the incidence of phlebitis across different cannula products, focusing on polyurethane.
Material and Methods: This is a post-hoc analysis of the AMOR-VENUS study that involved 23 ICUs in Japan. We included patients aged ≥ 18 years, who were admitted to the ICU with SPCs. The primary outcome was phlebitis, evaluated using hazard ratios (HRs) and 95% confidence intervals (CIs). Based on the market share and differences in synthesis, polyurethanes were categorized into PEU-Vialon® (BD, USA), SuperCath® (Medikit, Japan), and other polyurethanes; non-polyurethane materials were also analyzed. Multivariable marginal Cox regression analysis was performed using other polyurethanes as a reference.
Results: In total, 1,355 patients and 3,429 SPCs were evaluated. Among polyurethane cannulas, 1,087 (33.5%) were PEU-Vialon®, 702 (21.6%) were SuperCath®, and 276 (8.5%) were other polyurethanes. Among non-polyurethane cannulas, 1,292 (39.8%) were ethylene tetrafluoroethylene (ETFE) cannulas, and 72 (2.2%) used other materials. The highest incidence of phlebitis was observed with SuperCath® (13.1%). Multivariate analysis revealed an HR of 1.45 (95% CI 0.75-2.8, p = 0.21) for PEU-Vialon®, 2.60 (95% CI 1.35-5.00, p < 0.01) for SuperCath®, 2.29 (95% CI 1.19-4.42, p = 0.01) for ETFE, and 2.2 (95% CI 0.46-10.59, p = 0.32) for others.
Conclusions: The incidence of phlebitis varied among polyurethane cannulas. Further research is warranted to determine the causes of these differences.