Does ketamine have a role in managing severe exacerbation of asthma in adults?

Objective. To evaluate the role of ketamine in management of severe exacerb ation of asthma in adults. Methods. Qualitative systematic search using MEDLINE (January 1966-Septembe r 2000), EMBASE (January 1988-September 2000), and the Cochrane Database of Systematic Reviews (Issue 2, 2000). Results. One prospective, randomized, double-blind, placebo-controlled tria l and five case reports were retrieved. In the clinical trial, low-dosage k etamine as an adjunct to standard therapy offered no benefit in improving o utcomes in nonventilated patients. In the case reports, all patients with r efractory severe exacerbation of asthma requiring mechanical ventilation ap peared to receive some benefit from ketamine, with alleviation of bronchosp asin and improved oxygenation. Adverse effects included dysphoria, hallucin ations, and increased pulmonary secretions. Conclusion. Limited evidence is available in the literature to support admi nistration of ketamine in severe exacerbation of asthma. Although a few cas es suggest possible benefit from ketamine, it should not be considered unti l controlled clinical trials demonstrate that benefits outweigh risks for p atients for whom other standard therapies failed.