Most acute wheezing episodes in preschool children are associated with rhinovirus. Rhinovirus decreases extracellular adenosine triphosphate levels, leading to airway surface liquid dehydration. This, along with submucosal edema, mucus plaques, and inflammation, causes failure of mucus clearance. These preschool children do not respond well to available treatments, even oral steroids. This calls for pro–mucus clearance and prohydration treatments such as hypertonic saline in wheezing preschool children.
Randomized, controlled, double-blind study. Forty-one children (mean age 31.9 ± 17.4 months, range 1–6 years) presented with wheezing to the emergency department were randomized after 1 albuterol inhalation to receive either 4 mL of hypertonic saline 5% (HS) (n = 16) or 4 mL of normal saline (NS) (n = 25), both with 0.5 mL albuterol, twice every 20 minutes in the emergency department and 4 times a day thereafter if hospitalized. The primary outcome measured was length of stay (LOS) and the secondary outcomes were admission rate (AR) and clinical severity score.
The LOS was significantly shorter in the HS than in the NS group: median 2 days (range 0–6) versus 3 days (range 0–5) days (P = .027). The AR was significantly lower in the HS than the NS group: 62.2% versus 92%. Clinical severity score improved significantly in both groups but did not reach significance between them.
Using HS inhalations significantly shortens LOS and lowers AR in preschool children presenting with an acute wheezing episode to the emergency department.
We read with interest the article by Ater et al. who found that albuterol was more effective in combination with hypertonic saline (HS) than normal saline (NS) in preschool children with an acute wheezing episode [1]. We note that the HS group were older on average than the NS group, although this difference was not statistically significant (30 months compared to 19.7 months). However, an age difference of approximately ten months might result in significant discrepancies in height or weight between groups. Airway resistance is inversely associated with height and weight [2]. Differences in airway resistance between groups are likely to confound the outcome measures used in this study. Can the authors provide a statistical comparison of the mean height and weight of the two groups and comment on whether this might explain their findings?
1.Ater D, Shai H, Bar BE, et al. Hypertonic saline and acute wheezing in preschool children. Pediatrics. 2012;129:e1397-1403.
2.Gochicoa LG, Thome-Ortiz LP, Furuya ME, et al. Reference values for airway resistance in newborns, infants and preschoolers from a Latin American population. Respirology. 2012;17:667-673.
Conflict of Interest:
None declared
Ater D et al (1), recently published a study, the effectiveness of hypertonic saline (HS) treatment, with acute wheezing in preschool children. In this randomized, controlled, double-blind study, they compared nebulized HS (n=16) with normal saline (NS) (n=25) treatment in preschool children with acute wheezing. The main outcome of this article is the significant shortening of the median hospitalization in HS group comparing to NS group (respectively 2 days, 3 days). Additionally, the admission rate of HS group significantly less than NS group (respectively 62.2%, 92%). The study population here was defined as non-bronchiolitis and acute wheezing children. During respiratory syncytial virus (RSV) season, children with RSV bronchiolitis were excluded in this study. Positive viral PCR was found in 24 patient (Rhinovirus: 11, adenovirus: 6, bocavirus: 5, enterovirus: 5 etc.). However, we believe that this study needs a few comments in several points. Firstly; the authors stated that convictions "we believe that our population represents non-bronchiolitis, mostly virus-triggered wheezing, sometimes referred practically as "asthmatic" attacks in preschool children". Previously, it was known that HS is an effective therapy in the acute bronchiolitis (2). As the authors indicated, it might not be possible to describe the study group as non-bronchiolitis, virus-triggered wheezing or asthmatic. RSV positive children excluded here in this study however, as recent publications pointed out that rhinovirus, adenovirus, and bocavirus may cause acute bronchiolitis as well as RSV (3-5). Acute asthmatic wheezing occur with bronchial hyperreactivity in patients with eosinophilic airway inflammation caused by precipitating factors. The bronchial hyperreactivity can be possible described with respiratory function tests in school children. However, it is not every time possible in preschool children, unless their bronchial hyperreactivity is considered to be with recurrent wheezing as three or more attacks (6). In this study, it would be better to define study groups having with three or more wheezing attacks in preschool children. 80.5% of children presented with wheezing in the past and 46.3% of them with multiple-trigger past wheezing in this study. In other words, the estimated 20% of study population was admitted to hospital with first wheezing attacks and 54% were at most second attacks. Consequently, the definition for viral associated wheezing or acute asthmatic wheezing could not be clear as there is high probability for acute bronchiolitis. Secondly, the effect of nebulized NS therapy in respiratory tract disease is well known (7, 8). However, NS used as the control group could mask the real effect or treatment with nebulized HS. When placebo (such as sterile water) given to the control group, it could be more suitable than NS and so the effect of nebulized HS therapy revealed more clearly. Thirdly, we did not realize the certain points in this study. The mean age of HS, NS, and total study groups were 30?13.4, 19.7?33.1, and 17.4?31.9 months, respectively as mentioned on the table 2 (1). The mean age of total study group is lower than each HS and NS groups. We think this situation is not reasonable. Furthermore, we could not clearly 'HS group's number of ED visit in past year' sentences in Table -2 (1). Finally, we could not found reference 9 in the literature.
References 1. Ater D, Shai H, Bar BE, et al. Hypertonic saline and acute wheezing in preschool children. Pediatrics. 2012;129(6):e1397-403. 2. Zhang L, Mendoza-Sassi RA, Wainwright C, Klassen TP. Nebulized hypertonic saline solution for acute bronchiolitis in infants. Cochrane Database Syst Rev. 2008(4):CD006458. 3. Gern JE. The ABCs of rhinoviruses, wheezing, and asthma. J Virol. 2010;84(15):7418-26. 4. Mak RK, Tse LY, Lam WY, Wong GW, Chan PK, Leung TF. Clinical spectrum of human rhinovirus infections in hospitalized Hong Kong children. Pediatr Infect Dis J. 2011;30(9):749-53. 5. Midulla F, Scagnolari C, Bonci E, et al. Respiratory syncytial virus, human bocavirus and rhinovirus bronchiolitis in infants. Arch Dis Child. 2010;95(1):35-41. 6. Ducharme FM, Lemire C, Noya FJ, et al. Preemptive use of high-dose fluticasone for virus-induced wheezing in young children. N Engl J Med. 2009;360(4):339-53. 7. Khan SY, O'Driscoll BR. Is nebulized saline a placebo in COPD? BMC Pulm Med. 2004;30;4:9. 8. Kassel JC, King D, Spurling GK. Saline nasal irrigation for acute upper respiratory tract infections. Cochrane Database Syst Rev. 2010(3):CD006821.
Conflict of Interest:
We declare that we have no conflict of interest.
Please advise dose of albuterol nebulised, was it in with the study solutions 4ml plus 0.5ml ie 4.5 ml? 2.5mg in 5ml or 5mg in 5 ml are UK albuterol nebuliser doses. William Sellers
Conflict of Interest:
None declared