Universidad Pública de Navarra

While the transition from optical fiber to planar waveguide substrates in LMR-based sensors has allowed for the development of more robust, cost-effective, and easily manufactured platforms, it has also presented challenges in optimizing critical sensor parameters such as resolution and sensitivity in biosensing. In this work, we introduce the application of gold nanoparticles (AuNP) to enhance the sensitivity of a Lossy Mode Resonance (LMR)-based biosensor for the detection of vascular endothelial growth factor (VEGF) protein. The sensor was developed by depositing a nanometric TiO₂ film on a planar waveguide, and its performance was assessed using three detection approaches: label-free, sandwich assay, and AuNP-labeled sandwich assay. The integration of AuNP significantly improved sensitivity, enabling detection at concentrations as low as 0.1 ng mL^-1, surpassing the sensitivity of traditional label-free LMR-based sensors. These results demonstrate the potential of AuNP-enhanced LMR sensors for detecting low concentrations of biomarkers with high specificity and sensitivity, positioning them as promising tools for biosensing applications.

Peripheral intravenous catheters (PIVC) are essential medical devices, yet they frequently lead to complications such as phlebitis, infiltration, and occlusion. Identifying risk factors is key to reducing these complications.

To estimate the incidence of PIVC‑associated phlebitis in Spanish hospitals and identify clinical and epidemiological risk factors.

We performed a prospective cohort study in 80 Spanish hospitals from 1 to 28 February 2023. Adult inpatients (≥18 years) receiving PIVCs in non‑ICU, non‑emergency, non‑pediatric wards were eligible. A total of 13,812 PIVCs in 9387 patients were followed daily by trained nurses until catheter removal, phlebitis onset (Maddox grade ≥ 2), or 15 days. We calculated cumulative incidence and incidence density per 100 catheter‑days. Multivariable Cox proportional hazards models estimated hazard ratios (HRs) for predictors-sex, age group, number of infused medications, hospital size, and dwell time.

Phlebitis occurred in 1302 PIVCs (cumulative incidence 9.43 %; incidence density 0.14 per 100 person‑hours). Independent risk factors were female sex (HR 1.32, 95 % CI 1.21-1.45), age 65-79 years (HR 1.25, 95 % CI 1.12-1.40), administration of ≥ 2 medications (HR 1.50, 95 % CI 1.35-1.67), and hospital size ≥ 1000 beds (HR 1.30, 95 % CI 1.12-1.52). Phlebitis risk peaked 48-96 h post‑insertion.

Phlebitis incidence remains above recommended levels. Multivariable analysis identified female sex, a higher number of infused medications, older patient age, larger hospital size, and longer PIVC dwell time as the main independent predictors of phlebitis. Registration: Not registered.