Dexamethasone for treatment of patients mechanically ventilated for lower respiratory tract infection caused by respiratory syncytial virus

Glucocorticoids for acute viral bronchiolitis in infants and young children

BACKGROUND

Systemic glucocorticoids have been widely prescribed for use in infants and young children with acute viral bronchiolitis but the actual benefit of this intervention requires clarification.

OBJECTIVES

To systematically review the evidence on the effectiveness of systemic glucocorticoids for the treatment of infants and young children with acute viral bronchiolitis.

SEARCH STRATEGY

Multiple strategies were incorporated to maximize identification of suitable studies. The following databases were searched: the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2003); MEDLINE (January 1966 to September 2003); Current Contents (1998 to 2000); EMBASE (January 1990 to September 2003); and Sci Search. Handsearches through cited references and contacts with experts were also used.

SELECTION CRITERIA

Only randomised controlled trials (RCT) were eligible for inclusion. Studies were included if participants were diagnosed with acute viral bronchiolitis and treated with systemic (oral, intramuscular or intravenous) corticosteroids. Three reviewers independently selected potentially relevant articles. Four reviewers evaluated these studies, determined eligibility and assessed the methodological quality of each RCT.

DATA COLLECTION AND ANALYSIS

The primary outcome of interest was length of hospital stay (LOS). Secondary outcomes were: respiratory rate, haemoglobin oxygen saturation, and hospital admission and revisit rates. Data were extracted independently by the four reviewers and the results compiled and compared. Two reviewers reassessed studies to clarify points of discrepancy in the data extraction and database entry processes. Missing data were requested from the authors or calculated from other data presented in the study report.

MAIN RESULTS

There was complete agreement on the inclusion of 13 trials and the exclusion of five studies. Two main study recruitment groups were identified: a) infants and young children within the first 48 hours of hospitalisation (10 trials), and b) outpatient infants and young children who were randomised from the emergency department and who may nor may not have required hospital admission (three trials).A total of 1,198 children aged 0 to 30 months were treated with the equivalent of 0.5 to 10 mg/kg of systemic prednisone for two to seven days. Outcomes of interest were not measured in each RCT. In the pooled analysis of seven trials, there was a decrease in LOS in treated children of 0.38 days (95% confidence interval (CI) -0.81 to 0.05), indicating no significant difference between treatment groups. In the pooled analysis of eight trials, the day three clinical score measured: a standard mean difference (SMD) of -0.20 (95% CI -0.73 to 0.32), indicating no difference between treatment groups. Subgroup analyses for base LOS and clinical score outcomes were performed on infants who were a) less than 12 months of age, b) all respiratory syncytial virus (RSV) positive, c) treated with less than 6 mg/kg of prednisone equivalent throughout the illness and d) first-time wheezers. These were limited by the small number of studies in each subgroup. Hospital admission rates were examined in three trials and no difference was seen between treatment groups (odds ratio (OR) 1.05 (95% CI 0.23 to 4.87). Readmission rates were reported in six studies; with no significant differences between treatment groups. Hospital revisit rates were reported in three studies, with a significant difference between treatment groups reported in one study only. The respiratory rate and haemoglobin oxygen saturation were reported descriptively in six RCTs; no differences were found between groups. Co-interventions (oxygen, supportive fluids and bronchodilators) were used similarly between treatment groups in all RCTs.

REVIEWERS' CONCLUSIONS

No benefits were found in either LOS or clinical score in infants and young children treated with systemic glucocorticoids as compared to placebo. There were no differences in these outcomes between treatment groups; either in the pooled groups; either in the pooled analysis or in any of the sub analyses. Among the three studies evaluating hospital admission rates following the initial hospital visit there was no difference between treatment groups. There were no differences found in respiratory rate, haemoglobin oxygen saturation, hospital revisit or readmission rates. Subgroup analyses were significantly limited by the low number of studies in each comparison. Marked study heterogeneity and occasionally conflicting direction of benefit between trials suggests that these results should be interpreted with caution. Specific data on the harm of corticosteroid therapy in this patient population are lacking. Available evidence suggests that corticosteroid therapy is not of benefit in this patient group.

Short term outcome and risk factors for adverse clinical outcomes in adults with severe acute respiratory syndrome (SARS)

BACKGROUND

Severe acute respiratory syndrome (SARS) was diagnosed in Hong Kong in over 1700 patients between March and early June 2003.

METHODS

115 patients diagnosed with SARS were admitted to Queen Elizabeth Hospital, a large regional hospital in Hong Kong, from March 2003, of whom 100 were either discharged or were dead at 31 May. The patients were prospectively studied after admission to assess their short term outcomes and the risk factors associated with adverse outcomes, defined as death or the need for mechanical ventilation

RESULTS

At the time of writing 18 patients had died, with a crude mortality rate of 15.7% and a 21 day mortality of 10% (standard error 3%). Thirty nine patients (34%) were admitted to the intensive care unit, 30 of whom (26%) required mechanical ventilation. Multivariate analysis showed that age above 60 (hazards ratio (HR) 3.5, 95% CI 1.2 to 10.2; p=0.02), presence of diabetes mellitus or heart disease (HR 9.1, 95% CI 2.8 to 29.1; p<0.001), and the presence of other comorbid conditions (HR 5.2, 95% CI 1.4 to 19.7; p=0.01) were independently associated with mortality. However, only the presence of diabetes mellitus and/or cardiac disease (HR 7.3, 95% CI 3.1 to 17.4; p<0.001) was associated with adverse outcomes as a whole.

CONCLUSION

SARS is a new disease entity that carries significant morbidity and mortality. Specific clinical and laboratory parameters predicting unfavourable outcomes have been identified.