A salty solution or a pinch of salt? nHypertonic saline in Bronchiolitis
Date First Published:
June 12, 2015
Last Updated:
June 18, 2015
Report by:
Catherine Williams, Consultant Emergency Medicine (Royal Bolton Hospital)
Search checked by:
Catherine Williams, Royal Bolton Hospital
Three-Part Question:
In [infants with acute viral bronchiolitis] is [nebulised hypertonic saline] effective in [improving symptoms, reducing admission rate, or reducing length of stay]
Clinical Scenario:
A 4 month old infant presents to the ED with a 2 day history of coryza and cough. His mother reports he has become breathless over the last 24 hours and is no longer feeding as well as usual. You make a clinical diagnosis of bronchiolitis. You are aware that bronchodilators are not recommended in bronchiolitis but are keen to give some treatment. You wonder if hypertonic saline is effective.
Search Strategy:
Medline
Embase
Cochrane Database of Systematic Reviews
Clinical Trials.gov
Embase
Cochrane Database of Systematic Reviews
Clinical Trials.gov
Search Details:
Medline and Embase : (exp *bronchiolitis, viral/ OR exp *bronchiolitis OR bronchiolit*.af OR exp *RESPIRATORY SYNCYTIAL VIRUSES/ OR exp *RESPIRATORY SYNCYTIAL VIRUS INFECTIONS/ OR exp *RESPIROVIRUS INFECTIONS/ OR exp *RESPIRATORY TRACT INFECTIONS/ OR exp *PARAMYXOVIRIDAE INFECTIONS/ OR exp *INFLUENZA, HUMAN/ OR exp *ADENOVIRIDAE/ OR (infant* adj5 wheeze).af OR (wheez* adj5 bronchi*).af)AND ( (hypertonic AND saline).af OR exp *SALINE SOLUTION, HYPERTONIC/ OR exp *SODIUM CHLORIDE/ OR saline.af OR (3% ADJ saline).af OR (3% ADJ sodium AND chloride).af OR (3% ADJ NaCl).af OR (3 AND percent ADJ sodium AND chloride).af OR (3 AND percent ADJ NaCl).af OR (3 AND percent ADJ saline).af) AND (exp *"NEBULIZERS AND VAPORIZERS"/ OR exp *AEROSOLS/ OR exp *RESPIRATORY THERAPY/ OR nebulis*.af OR nebuliz*.af OR exp *ADMINISTRATION, INHALATION/ OR exp *AEROSOLS/ OR inhal*.af
Outcome:
2 meta analyses incorporating 11 RCTs.
20 RCTs in total of which 11 included in meta-analysis and not discussed seperately
20 RCTs in total of which 11 included in meta-analysis and not discussed seperately
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Nebulized hypertonic saline solution for acute bronchiolitis in infants Zhang L, Mendoza- Sassi R, Wainwright C, Klassen T. 2013 Brazil | Meta analysis of 11 RCTS, total patients 1090, 560 of whome received hypertonic saline (3% HS n=503, 5% HS n=57). 500 inpatients (5 trials); 65 outpatients (1 trial); 525 ED patients (4 trials) | Meta analysis of 11 RCTs of Nebulised hypertonic saline (3%) with or without broncho-dilators | Length of stay | Mean difference -1.15 days (95% CI -1.49 to -0.82) | |
| Clinical Severity score post treatment | Day 1 Mean difference -0.88 (95%CI -1.36 to -0.39) p=0.0004 Day 2 Mean difference -1.32 (95%CI -2.00 to -0.64) p=0.001 Day 3 Mean difference -1.51 (95%CI -1.88 to -1.14) p<0.00001 | ||||
| Nebulized Hypertonic Saline Treatment Reduces Both Rate and Duration of Hospitalization for Acute Bronchiolitis in Infants: An Updated Meta-analysis Yen-Ju Chen y, Wen-Li Lee y, Chuang-Ming Wang, 2014 Taiwan | Meta Analysis of 11 RCTs, including total of 1070 patients. | Meta analysis of 11 RCTs, includes 7 of the same papers as Zhang et al. | Duration of hospital admission | WMD=-0.96 (95% CI -1.38 to -0.54) p<0.001 | Sample size of included trials generally small and 6 did not use intention to treat analysis. |
| Rate of hospital Admissions | Risk Ratio 0.59 (95% CI 0.37-0.93) p=0.02 | ||||
| Effect on rate of readmission | Risk ratio=1.08 (95% CI=0.68-1.73; p=0.74 | ||||
| Effect on clinical severity score: Day 1 | WMD= -0.77 (95% CI -1.31- -0.24) p=0.005 | ||||
| Day 2 | WMD= -0.85 (95% CI -1.30- -0.39) p<0.001 | ||||
| Day 3 | WMD= -1.36 (95% CI -1.70- -1.02) p<0.001 | ||||
| Effectiveness of hypertonic saline and epinephrine in hospitalised infants with bronchiolitis Miraglia Del Giudice M, Saitta, F, Leonardi S, Capasso M, Niglio C, Chinellato I, Decimo F, et al 2012 Italy | 106 Hospitalised infants < 2 years with bronchiolitis | Double blinded Randomised controlled trial of 6 hrly nebulised 0.9% vs 3% saline (both with epinephrine) | Length of stay | 3% : 4.9 +/- 1.3 days vs. 0.9%: 5.6 +/-1.6 p<0.05 | No power calculation performed 3 patients withdrew consent after randomisation- not clear if intention to treat or per protocol analysis used or reasons for withdrawal |
| Clinical severity score | Day 1: 8.8 +/- 1.5 vs. 8.5 +/-1.4 p=NS Day 2: 8.3 +/- 1.7 vs. 7.4 +/- 1.6 p<0.005 Day 3: 7.7 +/- 1.6 vs. 6.6 +/-1.6 p<0.005 | ||||
| Hypertonic (3%) Saline Vs 0.9% Saline Nebulization for Acute Viral Bronchiolitis: A randomized controlled trial Sharma B; Gupta M, Rafik S 2013 India | 250 Infants 1-24 months hospitalised with bronchiolitis with clinical severity score 3-6 (moderate) | Randomised double blinded controlled trial nebulised with 4ml 3% or 0.9% saline (both with 2.5mg salbutamol) at 4 hourly intervals | Length of stay | HS: 63.93h +/- 22.43 vs. NS: 63.51 +/- 21.27 p=0.878 | Details of 2 patients withdrawn from NS arm not given. Per protocol analysis used |
| Clinical severity scores | No significant difference between groups | ||||
| A comparative study on the use of 3% saline versus 0.9% saline nebulization in children with bronchiolitis Ojha A, Mathema S, Sah S, Aryal U 2014 Nepal | 72 Infants aged 45 days to 2 years hospitalised with bronchiolitis. Mean age 8.56 months | Double blind randomised controlled trial of nebulised 4ml 0.9% vs. 3% saline administered three times daily | Length of stay | NS: 44.82 (+/-23.15) vs. HS: 43.60 (+/- 28.25) p=0.86 | Small trial, underpowered as although appropriate number recruited, 13 withdrew before completion. Per protocol analysis used. |
| Duration of oxygen supplementation | NS: 34.50 (+/-26.03) vs HS: 32.50 (+/-20.44) p=0.85 | ||||
| Time for normalisation of clinical score | NS: 38.34 (+/-26.67) vs. HS:36.79 (+/-19.53) p=0.80 | ||||
| SABRE: a multicentre randomised control trial of nebulised hypertonic saline in infants hospitalised with acute bronchiolitis Everard M, Hind D, Ugonna K, Freeman J, Bradburn M, Cooper C, Cross E, Maguire C, Cantrill H, et al 2014 UK | 317 Infants under 1 year of age admitted with bronchiolitis and requiring oxygen therapy | Open multicentre parallel group pragmatic RCT in 10 UK hospitals. Usual care vs. 3% hypertonic saline 4 hourly | Time to 'fit for discharge' | Hazard ratio 0.95 (95%CI 0.75-1.20) | Non blinded. |
| Time to discharge | Hazard ratio 0.97 (95% CI 0.76-1.23) | ||||
| The effect of 3% and 6% hypertonic saline in viral bronchiolitis: A randomised controlled trial Teunissen J, Hochs A, Vaessen-Verbene A, Boehmer A, Smeets C, Brackel H, van Gent R, et al 2014 Netherlands | 292 infants (median age 3.4 mo) hospitalised with bronchiolitis enrolled, 242 completed study | Multicentre double blind randomised controlled trial, comparing nebulised 6%, 3% and 0.9% saline (all with salbutamol) | Length of stay | 6%; 70 h (IQR69) vs. 3%: 69 h (IQR 57) vs. 53h (IQR 52) p=0.29 | Large number of withdrawals |
| Nebulized hypertonic saline for bronchiolitis: a randomized controlled trial Wu S, Baker C, Lang M, Schrager S, Liley F, Papa C, Mira V, Balkian A, Mason W 2014 USA | 408 children under 24 months presenting to the ED of 2 tertiary children's hospitals | Double blind randomized controlled trial over 3 consecutive bronchiolitis seasons. 4ml 3% vs 0.9% saline up to 3 times in the ED and then 8 hourly if admitted. Patients premedicated with albuterol. | Admission rate | HS: 28.9% vs NS: 42.6%. OR 0.49 (95% CI 0.28-0.86) | |
| Length of stay | HS: 3.16d vs. 3.92 d p=0.24 | ||||
| Nebulized hypertonic saline for bronchiolitis in the Emergency Department: a randomized controlled trial Florin T; Shaw K; Kittick M; Yakscoe S; Zorc J 2014 USA | 62 patients aged 2-24 months with first episode bronchiolitis and RDAI 4-15 (moderate-severe) | Double blinded randomised controlled trial. 3% vs 0.9% saline administered once in the ED. Both groups treated with albuterol before trial intervention. | Change in RDAI (reduction=improvement) | HS: -1 vs NS: -5 p:0.01 | Small trial. Short observation period |
| Does the nebulized 3% hypertonic saline solution reduce admissions to PICU in acute bronchiolitis? Flores-Gonzales J, Comino-Vazquez P, Rodriquez-Campoy P, Jiminez-Gomez G, Matamala-Morillo M, et al 2014 Spain | 389 patients with moderate acute bronchiolitis. | Data on 181 (group 0) collected retrospectively treated with 0.9% saline (+ bronchodilators) and 208 (group 1) prospectively treated with 3% saline (+ bronchodilators). | PICU admission rate | Group 0: 17.8% vs. Group 1:12.5% p=0.146 | Before and after study, unblinded. Corticosteroids and antibiotics both used. |
| PICU length of stay | Group 0: 5.91 vs Group 1: 3.76 p=0.859 | ||||
| Mechanical ventilation rate | 25% vs 24% p=0.931 | ||||
| 7% hypertonic saline in acute bronchiolitis: a randomised controlled trial Jacobs J, Foster M, Wan J, Pershad J 2014 USA | 101 infants with moderate to severe acute bronchiolitis | Prospective double blind randomized controlled trial of 7% vs 0.9% saline, both with epinephrine | Change in severity score | HS: 2.6 (=/-1.9) vs NS: 2.4 (=/-2.3) Diff in means 0.21(95% CI -0.61-1.03) p=0.61 | |
| Admission rate | HS: 42% vs. NS: 49%. OR 0.76 (95% CI 0.35-1.7) |
Author Commentary:
Bronchiolitis is a common presentation to Emergency Departments and paediatric units in the winter months and effective treatment is very limited.
Bronchiolitis may occur due to infection with a range of viruses, most commonly respiratory syncytial virus (RSV). The pathophysiology is substantially different from that in older patients with wheeze which may explain the lack of benefit from bronchodilator therapy. In bronchiolitis, small airway obstruction occurs as a result of bronchiolar inflammation, leading to a combination of mucosal oedema, mucus plugging and sloughing of necrotic bronchiolar mucosa within the narrow bronchiolar lumen. It is suggested that hypertonic saline may reduce mucosal oedema, rehydrate the airway surface liquid, disrupt ionic bonds within mucus plugs and encourage expectoration.
The included trials are all of reasonable quality although some are relatively small, however most use a physiologically active placebo (0.9% saline) and many also use some form of bronchodilator, which are generally accepted to be ineffective in bronchiolitis. Since the most recent meta-analysis in 2014 which was supportive of hypertonic saline therapy in bronchiolitis, a further 9 RCTs have been published, 7 of which demonstrated no advantage of hypertonic saline over 0.9% saline. The SABRE trial, which is the only trial to date to avoid the use of a potentially physiological placebo did not demonstrate any benefit from hypertonic saline.
Overall it seems likely that, although there may be a benefit to the use of hypertonic saline, the clinical effect is small, hence the conflicting results of the 20 RCTs to date.
Bronchiolitis may occur due to infection with a range of viruses, most commonly respiratory syncytial virus (RSV). The pathophysiology is substantially different from that in older patients with wheeze which may explain the lack of benefit from bronchodilator therapy. In bronchiolitis, small airway obstruction occurs as a result of bronchiolar inflammation, leading to a combination of mucosal oedema, mucus plugging and sloughing of necrotic bronchiolar mucosa within the narrow bronchiolar lumen. It is suggested that hypertonic saline may reduce mucosal oedema, rehydrate the airway surface liquid, disrupt ionic bonds within mucus plugs and encourage expectoration.
The included trials are all of reasonable quality although some are relatively small, however most use a physiologically active placebo (0.9% saline) and many also use some form of bronchodilator, which are generally accepted to be ineffective in bronchiolitis. Since the most recent meta-analysis in 2014 which was supportive of hypertonic saline therapy in bronchiolitis, a further 9 RCTs have been published, 7 of which demonstrated no advantage of hypertonic saline over 0.9% saline. The SABRE trial, which is the only trial to date to avoid the use of a potentially physiological placebo did not demonstrate any benefit from hypertonic saline.
Overall it seems likely that, although there may be a benefit to the use of hypertonic saline, the clinical effect is small, hence the conflicting results of the 20 RCTs to date.
Bottom Line:
Hypertonic saline is safe and may be a useful therapy for patients with acute bronchiolitis, however clinical effects appear relatively small and the main focus should remain on providing quality supportive care.
References:
- Zhang L, Mendoza- Sassi R, Wainwright C, Klassen T.. Nebulized hypertonic saline solution for acute bronchiolitis in infants
- Yen-Ju Chen y, Wen-Li Lee y, Chuang-Ming Wang,. Nebulized Hypertonic Saline Treatment Reduces Both Rate and Duration of Hospitalization for Acute Bronchiolitis in Infants: An Updated Meta-analysis
- Miraglia Del Giudice M, Saitta, F, Leonardi S, Capasso M, Niglio C, Chinellato I, Decimo F, et al. Effectiveness of hypertonic saline and epinephrine in hospitalised infants with bronchiolitis
- Sharma B; Gupta M, Rafik S. Hypertonic (3%) Saline Vs 0.9% Saline Nebulization for Acute Viral Bronchiolitis: A randomized controlled trial
- Ojha A, Mathema S, Sah S, Aryal U. A comparative study on the use of 3% saline versus 0.9% saline nebulization in children with bronchiolitis
- Everard M, Hind D, Ugonna K, Freeman J, Bradburn M, Cooper C, Cross E, Maguire C, Cantrill H, et al. SABRE: a multicentre randomised control trial of nebulised hypertonic saline in infants hospitalised with acute bronchiolitis
- Teunissen J, Hochs A, Vaessen-Verbene A, Boehmer A, Smeets C, Brackel H, van Gent R, et al. The effect of 3% and 6% hypertonic saline in viral bronchiolitis: A randomised controlled trial
- Wu S, Baker C, Lang M, Schrager S, Liley F, Papa C, Mira V, Balkian A, Mason W. Nebulized hypertonic saline for bronchiolitis: a randomized controlled trial
- Florin T; Shaw K; Kittick M; Yakscoe S; Zorc J. Nebulized hypertonic saline for bronchiolitis in the Emergency Department: a randomized controlled trial
- Flores-Gonzales J, Comino-Vazquez P, Rodriquez-Campoy P, Jiminez-Gomez G, Matamala-Morillo M, et al. Does the nebulized 3% hypertonic saline solution reduce admissions to PICU in acute bronchiolitis?
- Jacobs J, Foster M, Wan J, Pershad J. 7% hypertonic saline in acute bronchiolitis: a randomised controlled trial