Evidence Based Medicine

Indian Pediatrics 1999; 36:526-527

Bronchodilator Therapy in Bronchiolitis

Kellner JD, Ohlsson A, Gadomski AM, Wang EEL. Bronchodilator therapy in bronchiolitis (Cochrane Review). In: The Cochrane Library, Issue 4, 1998. Oxford: Update Software.

Objective: To determine if bronchodilators are efficacious in treating bronchiolitis. Search strategy: A search of bibliographic databases (Medline, Excerpta Medica and Reference Update) for bronchiolitis and albuterol or ipratropium or adrenergic agents or bronchodilator agents. Reference lists were also used. Selection criteria: Randomized, placebo-controlled trials of treatment with bronchodilators in bronchiolitis were selected by two investigators. Fifteen of 89 identified publications met these criteria. Six further trials were subsequently identified in a MEDLINE and have been included. Data - collection and analysis: Investigators independently abstracted data for 3 outcomes: clinical score, oxygen saturation and hospitalization. Clinical score was measured as a dichotomus variable (score ± improved) or continuous variable (average score). In addition to the binary outcome of hospital admission, duration of hospitalization was compared for inpatient studies. Main results: There were five outcomes: A significant increase in the proportion of children demon- strating an improved clinical score was seen with bronchodilators (Peto Odds Ratio 0.29, 95% CI 0.19 to 0.45). However, this may have . been biased to show benefit by inclusion of studies which enrolled recurrent wheezers. A significant improvement was also observed in the pooled estimate of the clinical score (weighted mean difference -0.2, CI -0.27 to -0.1), but the clinical importance of the magnitude of difference is questionable. There was no benefit of bronchodilator therapy on oxygen saturation (WMD 0.7, CI 0.5 to 0.85), rate of hospitalization (OR 0.7, CI 0.36 to 1.36) or duration of hospitalization (WMD 0.12, CI -0.3 to 0.5). Conclusions: Bronchodilators produce modest short term improvement in clinical scores. Given the costs of these agents and their minimal benefit, they cannot be recommended for routine management of bronchiolitis.

Comments

Bronchiolitis is a common, though not of- ten recognized, illness even among children in tropical regions, including India(1). In young infants in India, it comprises a significant proportion of all acute respiratory infections requiring hospitalization(1). The treatment of this condition is essentially supportive. Specific therapy, Le., aerosolized ribavirin is not available in India. Even where it is available, its use remains controversial. A recent meta-analysis of randomized controlled trials of ribavirin in RSV bronchiolitis has not shown a clear cut benefit(2).

Bronchodilators, systemic or inhaled, are commonly used. in the treatment of bronchiolitis(3). Despite their widespread use, there is no consensus about the benefit of bronchodilators in bronchiolitis. A recent . published meta-analysis concluded that bronchodilators produce modest short term improvement in clinical features of mild or moderately severe bronchiolitis(4). The abstract presented here is a more updated meta-analysis by the same authors. In this reveiw, the authors are more cautious in making a definite conclusion about the benefit of bronchodilators in bronchiolitis. Though they found an overall benefit in clinical scores, the significance of the improvement in scores is uncertain. Also, two studies which showed the greatest benefit included children with re- current wheeze (more likely to be asthma rather than bronchiolitis). The other outcome parameters, such as improvement in oxygen saturation or the need or duration of hospitalization, were not significantly different be- tween the treatment and placebo groups. However, as the authors themselves pointed out in their discussion, improvement in oxygen saturation is unlikely to occur in infants with mild or moderate disease where the baseline oxygen saturation may have been normal or close to normal. Also, the need for hospitalization and duration of hospital stay are fairly subjective and prone to error unless very specific criteria were used for admission and discharge from hospital (which was not so in many of the studies reviewed).

Thus, the efficacy of bronchodilators in bronchiolitis remains an unresolved issue. It is clear that there does not appear to be any striking benefit. It is also clear that children with asthma, Le., those with recurrent wheeze would clearly benefit. Further studies with well defined outcome measures, which would correlate well with clinical benefit, are required to answer this question. In the mean- while, it may be worth a trial of inhaled bronchodilator in children with the first episode of wheeze. If the first few doses do not result in any appreciable benefit, further doses may be avoided because of potential toxicity and unnecessary expense.
 

Thomas Cherian,
Department of Child Health,
Christian Medical College and Hospital,
Vellore 632 004, Tamilnadu,
India.
 

References