Background Bronchiolitis is a common lower respiratory tract infection of infancy. In theUK, 3% of all infants are hospitalised with bronchiolitis and this places a considerable burden on the NHS every winter. An admission costs £600/day in our institution. Identification of factors associated with the duration of hospitalisation with bronchiolitis may be of interest to clinicians and healthcare commissioners and this was the aim of the present study.

Methods Data were collected from infants aged up to 6 months and admitted to hospital with a diagnosis of bronchiolitis during the winters 2003/4–2010/11 inclusive. The outcome was duration of stay (hours). Predictive variables included weight, age and observations on admission, gender, socioeconomic status, distance from home to hospital, number of infants admitted that winter and winter of admission. A clinical pathway was introduced after winter 2004/51.

Results Data were available in 382 infants, 322 were RSV positive. The median (IQR) duration of stay was 66 hours (38, 99). Initial univariate analyses indicated that the following were positively associated with duration of stay: younger age (Rho-0.31), lower weight (Rho-0.31), increased heart (Rho0.17) and respiratory rate (Rho0.18), detection of RSV (mean duration of stay 84 for RSV positive vs 48 hours for RSV negative) and smaller number of infants admitted that winter (Rho-0.17). The duration of stay also varied by year and was reduced after introduction of the clinical pathway1. In the multivariate analysis (R2 = 0.29, n = 347), the following remained significantly associated with log transformed duration of stay: respiratory rate (p = 0.003), infant weight (p < 0.001), RSV detected (p < 0.001) and winter of admission (p < 0.001).

Conclusions The duration of stay for bronchiolitis, measured over eight successive seasons, appeared to be partly driven by host and pathogen factors. There are differences between years, e.g. a “busy” season, introduction of a clinical pathway which may lead to a reduction in duration of stay. However, most of the variation in the duration of stay within this population was explained by variables not measured and may include random factors.

Reference

1. Walker C, Danby S, Turner SW. Impact of a bronchiolitis clinical care pathway on hospital stay. Eur J Pediatr 2012; 171:827–832.