Acute viral bronchiolitis is the most common lower respiratory tract infection in infants up to two years old. Currently there is no effective treatment so standard treatment remains supportive care. Airway oedema (abnormal accumulation of fluid) and mucus plugging can cause wheezing and difficulty breathing in these patients. Nebulised hypertonic saline may be a beneficial treatment to manage acute bronchiolitis because it can improve airway hygiene. This review was conducted to assess the effects of hypertonic (≥ 3%) saline solution administered via a nebuliser in infants with acute bronchiolitis, compared with nebulised normal (0.9%) saline. The establishment of a therapeutic role for hypertonic saline solution may provide a cheap and effective therapy for these patients. We included 11 randomised trials involving 1090 infants with mild to moderate bronchiolitis. All but one of the 11 trials are considered as high-quality studies with low risk of error (i.e. bias) in their conclusions. Meta-analysis suggests that nebulised hypertonic saline could lead to a reduction of 1.2 days in the mean length of hospital stay among infants hospitalised for non-severe acute bronchiolitis and improve the clinical severity score in both outpatient and inpatient populations. No significant short-term effects (at 30 to 120 minutes) of one to three doses of nebulised hypertonic saline were observed among emergency department patients. However, more trials are needed to address this question. There were no significant adverse effects noted with the use of nebulised hypertonic saline when administered along with bronchodilators. Given the clinically relevant benefit and good safety profile, nebulised hypertonic saline used in conjunction with bronchodilators should be considered an effective and safe treatment for infants with mild to moderate acute viral bronchiolitis
