Effects of Palivizumab Guideline Changes on RSV Admissions in Patients with Congenital Heart Disease and Prematurity

Background: Respiratory syncytial virus (RSV) causes significant morbidity and mortality in patients with a history of prematurity and congenital heart disease (CHD). In 2014, the guidelines for Palivizumab became more restrictive for this population. We hypothesized the percentage of RSV+ admissions would increase overall and in this target group (TG) specifically. Methods: We conducted a retrospective review of patients under age 2 years admitted with bronchiolitis two seasons prior to the change (Pre) and two seasons after (Post). Our TG included patients who were eligible prior to the 2014 changes but currently no longer eligible. We used chi-square analysis to answer the two main hypotheses: 1) Percent RSV+/total bronchiolitis Pre vs Post and 2) Percent of TG/RSV+ Pre vs Post. Results: 1283 patients (546 pre, 737 post) were admitted with the diagnosis of RSV between 2012-2016, 866 actually tested positive for RSV (367 Pre, 499 Post). There was no significant difference in the number of total patients admitted with RSV (Pre = 67.2%, Post = 67.7%) or in our TG (Pre 7.1% vs Post 8.2%). TG overall had a more complicated course: longer length of stay, median 5 days, IQR 2 - 12 vs 3 days, IQR 1 - 5, (p < 0.001), intensive care unit admissions (36% vs 22.8%, p = 0.02), positive pressure ventilation (25.4% vs 15.4%, p = 0.03) and intubation (16.4% vs 6.8%, p = 0.004), but there was no difference Pre vs Post. Conclusion: The TG had an overall higher acuity, but there was no increase in the number of patients hospitalized with RSV or severity as a result of the Palivizumab guideline changes.