Ketamine for Adults with Severe Asthma Exacerbation: A Systematic Review and Meta-analysis

BACKGROUND: Severe asthma mandates careful attention and timely management, and the benefit of ketamine in severe asthma exacerbations in adult patients require further exploration. METHODS: We conducted a systematic review and meta-analysis of the use of ketamine in cases of acute asthma exacerbation in adults. We searched PubMed, Google Scholar, Cochrane databases, and gray literature (ClinicalTrials.gov and World Health Organization International Clinical Trials Registry Platform); we also searched the reference lists of included articles and any systematic reviews and meta-analyses identified therein. Our search covered the period from 1963 to August 20, 2021. Search terms were “ketamine” AND “asthma”. RESULTS: Of 25 540 articles, two studies were included in the analysis. The total number of patients included in the studies was 136 (68 in the ketamine groups and 68 in the placebo group). The pooled effect size was 0.30 (95% CI: -0.04, 0.63) favouring ketamine over placebo, p=0.08, (I2=0%, p=0.39). A paired t-test revealed that ketamine improved the mean peak expiratory flow rate (PEFR) from 242.4 (SD=146.23) to 286.95 (SD=182.22), p=0.33, representing an 18.38% improvement. CONCLUSION: Ketamine can induce a 30% improvement in PEFR, representing a small positive effect in the treatment of acute severe asthma exacerbation in the emergency department (ED). The improvement was not statistically significant; nonetheless, since the improvement could be as great as 63% versus only a 4% possibility of no benefit/harm, the benefit appears to considerably outweigh any harm.