• Paediatric Lung Disaese

Nebulised hypertonic saline is attractive as a therapy for acute viral bronchiolitis. Thick and sticky secretions in oedematous airways induce breathlessness and poor feeding as a hallmark of the disease. Loosening secretions with this simple therapy could prevent admission to hospital, or speed recovery and discharge. In a condition with no current acute therapeutic options, this would be welcome indeed.1 ,2 Hypertonic saline changes mucous rheology, and when used in cystic fibrosis, has good—if modest—effect.3

In bronchiolitis, hypertonic saline has had a promising start. Early trials demonstrated appealing benefits with reduction in length of stay by up to 25%.4 A Cochrane review, last updated in 2013, concludes with a recommendation to use hypertonic saline in bronchiolitis to reduce length of stay in hospitalised patients.5

Hypertonic Saline in acute Bronchiolitis RCT and Economic evaluation (SABRE), printed in this issue,6 is the largest reported study for the use of nebulised hypertonic saline infants hospitalised with bronchiolitis. Importantly, the study protocol challenges head on the difficulties with using a placebo control when testing a nebulised intervention. As it cannot be assumed that nebulised normal saline (0.9%) will have no clinical effect, the non-intervention arm in SABRE was the current standard of care in the UK— i.e., no regular use of epinephrine, salbutamol or 0.9% saline that were nebulised in all previous studies testing hypertonic saline in bronchiolitis. By necessity, that made the trial open label, which leaves a study open to criticism of potential confounding bias. In this case, however, the weight of evidence to date in favour of hypertonic saline and the desperate need for something to work in bronchiolitis, might suggest any anticipated bias would have been in favour of the intervention. Yet, the open label design did not favour the intervention: nebulised hypertonic saline …