Background Several clinical trials have shown that nirsevimab, an antibody targeting the respiratory syncytial virus (RSV), reduces RSV-bronchiolitis requiring admission. In 2023-2024, Catalonia and Andorra adopted immunization strategies for children < 6 months and those born during the epidemic season. This study evaluates the effectiveness of nirsevimab in preventing hospitalizations from RSV bronchiolitis. Methods In the epidemic season of 2023-2024, a test-negative case-control study was conducted in three hospitals from Catalonia and Andorra. Patients <12 months old admitted with bronchiolitis and tested for RSV using molecular microbiology tests were included. The effectiveness in preventing RSV-bronchiolitis hospitalization and severe disease was estimated using multivariate models. Comparisons between immunized, non-immunized and non-eligible patients were made in prospectively collected epidemiological, clinical, and microbiological variables. Results 234 patients were included. RSV was detected in 141/234(60.2%), being less common in the immunized group (37% vs 75%, p<0.001). The rate of immunized patients among those eligible was 59.7%. The estimated effectiveness for RSV-associated lower respiratory tract infection was 81.0% (95% confidence interval: 60.9-90.7), and for preventing severe disease (the need for NIV/CMV), 85.6% (41.7-96.4%). No significant differences by immunization status were observed in patients with RSV concerning viral co-infections, the need for NIV/CMV or length of hospital stay. Conclusions This study provides real-world evidence of the effectiveness of nirsevimab in preventing RSV-LRTI hospitalization and severe disease in infants during their first RSV season following a systematic immunization program. Immunized patients did not exhibit a higher rate of viral co-infections nor differences in clinical severity once admitted.

Purpose: Children with bronchiolitis admiteed to the pediatric intensive care unit (PICU) for acute respiratory failure may require respiratory support with non-invasive ventilation (NIV). Enteral nutrition (EN) is associated with a reduction in hospital stay. Even so, guidelines do not specify on how to initiate, increase and maintain EN in these patients. Methods This was a prospective interventional study. Inclusion criteria were patients with bronchiolitis under NIV. A multidisciplinary team created an algorithm to improve EN for critically ill patients with bronchiolitis in need of NIV. In order to assess the protocol implementation, two periods of time were compared: Group 1: without nutrition implementation protocol vs Group 2, once the protocol was implemented. The project aim was to decrease the mean time to EN initation by 50% after the start of NIV. Secondary endpoints were time to reach target calories ( 100 kcal/kg/day), NIV duration, and % of patients with adverse effects. Results Hundred two patients were included in this study. In group 1, Forty eight and 54 in group 2. Statistically significant differences were detected in the main outcome. The mean time until the start of EN decreased from 18.5 hours to 6 hours (p<0.05) Median time to reach calorie goal decreased from 103.5 hours to 48.5 hours (p<0.05). No differences were dettected in other outcomes. Conclusions The implementation of a standardized route for EN in patients with NIV allow a decrease in the time of the start feeds and the time to the goal of caloric enteral nutrition.

A document by Daniel Penela-Sánchez. Click on the document to view its contents.