Evidence-Based Child Health Clinical Answer: Intervention

QUESTIONIn outpatient and inpatient infants with bronchiolitis, is nebulized 3% saline compared to no treatment effective in reducing rate of hospitalization (outpatients), duration of hospitalization (inpatients) and symptom severity?
ANSWERYes. Although no studies compared this intervention to no treatment, there is strong, high-quality evidence supporting the use of nebulized 3% saline to reduce inpatient length of stay and outpatient and inpatient clinical severity scores.
IMPLICATIONS FOR PRACTICEFor outpatients with acute bronchiolitis, nebulized 3% saline should be given to improve clinical scores later in the illness. Similarly, for patients admitted to hospital, nebulized 3% saline driven using oxygen may be given to improve respiratory distress and shorten the length of stay. The ideal dose frequency is currently unclear, but most studies administer the treatment three to six times daily. This treatment is likely to be most beneficial during the first three days of admission.
BACKGROUND• Bronchiolitis is a viral infection that is initially characterized by rhinorrhoea and low-grade fever, which progresses in a few days to cough, respiratory distress, tachypnoea, chest wall retractions, wheeze and/or crackles and occasionally apnoea. • Bronchiolitis is the most common acute infection of the lower respiratory tract during the first year of life.
SEARCH STRATEGY• Issue 9, 2011 of the Cochrane Database of Systematic Reviews was searched using the terms ‘bronchiolitis and saline’ restricted to the title, abstract or keywords.
INCLUDED REVIEWS• Of two potential reviews, one review (with a total of seven trials and 581 children) was included in this analysis. We used an updated (2010) version of this review. • Table1 presents characteristics of the included review.
RESULTS• The included review compared nebulized 3% saline to 0.9% saline. Table2 presents a summary of the results. • 3% saline did not affect the outpatient rate of hospitalization (RR: 0.63; 95% CI: 0.34, 1.17). However, there was a decrease in clinical severity score on day 1 (MD: − 1.28; 95% CI: − 1.92, − 0.64), 2 (MD: − 2.00; 95% CI: − 2.93, − 1.07) and 3 (MD: − 2.64; 95% CI: − 3.85, − 1.43). • For inpatients with bronchiolitis, 3% saline decreased the mean length of stay by 28 hours (MD: − 1.16; 95% CI: − 1.55, − 0.77). • For inpatients, 3% saline led to a decrease in clinical severity score on day 1 (MD: − 0.82; 95% CI: − 1.59, − 0.06; I2: 73%), 2 (MD: − 1.14; 95% CI: − 1.75, − 0.53; I2: 57%) and 3 (MD: − 1.07; 95% CI: − 1.69, − 0.44; I2: 53%).
LIMITATIONS• The included review did not contain the intervention and comparison groups specified in the clinical question. However, the available evidence presents strong data supporting the use of nebulized 3% saline for outpatients and inpatients with bronchiolitis. • Data for inpatient clinical scores must be interpreted with caution as these analyses contained significant heterogeneity (ranging from 53% to 73%).
Table I. Characteristics of included reviews
Review titleNumber of studiesPopulationInterventionComparisonOutcomes for which data were reported
AuthorsStudy sample size (range)Definition of bronchiolitis   
Assessed as up-to-date     
Nebulized hypertonic saline solution for acute bronchiolitis in infants7Outpatient and inpatient infants up to two years oldNebulized 3% hypertonic salineNebulized 0.9% salineOutpatient: rate of hospitalization, rate of readmission and clinical severity scores
Zhang L, Mendoza-Sassi RA, Wainwright C, Klassen TP581 (44–186)Acute bronchiolitis: first episode of acute wheezing associated with clinical evidence of a viral infection (cough, coryza or fever). Children with recurrent wheezing were excluded  Inpatient: length of hospital stay and clinical severity scores
June 2010     
Table II. Hospitalization rate, length of stay and clinical severity scores
PopulationOutcomeNumber of subjects (studies)Measure of effect (95% CI)I2 (%)
  • a

    Significantly favours 3% hypertonic saline.

  • CI: confidence interval; MD: mean difference (measured using random effects modelling); RR: risk ratio (measured using random effects modelling).

OutpatientHospitalization rate262 (3)RR: 0.63 (0.34, 1.17)0
 Clinical severity score on day 165 (1)MD: − 1.28 (−1.92, − 0.64)a
 Clinical severity score on day 265 (1)MD: − 2.00 (−2.93, − 1.07)a
 Clinical severity score on day 365 (1)MD: − 2.64 (−3.85, − 1.43)a
InpatientLength of hospital stay (days)282 (4)MD: − 1.16 (−1.55, − 0.77)a0
 Clinical severity score on day 1186 (3)MD: − 0.82 (−1.59, − 0.06)a73
 Clinical severity score on day 2183 (3)MD: − 1.14 (−1.75, − 0.53)a57
 Clinical severity score on day 3156 (3)MD: − 1.07 (−1.69, − 0.44)a53