Can nebulized ketamine lead to improved outcomes in severe asthma exacerbations?
Date First Published:
January 17, 2023
Last Updated:
January 17, 2023
Report by:
Janie O'Leary, Resident Physician (Queen's University)
Three-Part Question:
In [patients presenting with severe asthma exacerbation] is [nebulized ketamine] effective in [improving outcomes]?
Clinical Scenario:
A patient with a history of asthma presents to your Emergency Department with a severe exacerbation. Despite treatment with standard therapies, the patient continues to deteriorate, and you begin to prepare for intubation. You are aware of the reported potential bronchodilatory properties of ketamine and wonder if treatment with nebulized ketamine may avoid the need for intubation and mechanical ventilation.
Search Strategy:
Medline (1946-present) via OVID interface was searched using the following strategy: (ketamine.mp. or exp Ketamine/ or ketalar.mp.) and (exp "Nebulizers and Vaporizers"/ or exp Administration, Inhalation/ or nebuliz*.mp. or exp Aerosols/ or exp asthma/ or exp status asthmaticus/ or bronchial hyperreactivity/ or exp bronchial spasm/ or asthma.mp.)
Outcome:
The search strategy yielded 278 papers. This was narrowed to one randomized controlled trial (RCT) . Other papers were excluded on the basis of ketamine use for indications other than asthma exacerbation and ketamine delivery via routes other than nebulization. Animal studies and a single case report were also excluded.
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| The effects of nebulized ketamine and intravenous magnesium sulfate on corticosteroid resistant asthma exacerbation; a randomized clinical trial Farshadfar, K., Sohooli, M., Shekouhi, R., Taherinya, A., Qorbani, M., & Rezaei-Kojani, M. 2021 Iran | 70 patients aged 18 to 65 years old presenting to the emergency department with severe asthma exacerbation not responding to first-line therapies | Double-blinded randomized controlled trial comparing nebulized ketamine (0.1-0.3 ml/kg) and intravenous magnesium sulfate (MgSO4; 2 g over 20 minutes) | Small sample size from single centre. Patient characteristics such as duration of asthma exacerbation, number of previous exacerbations, medical comorbidities not summarized. Detailed information regarding pre-study treatments received by patients not provided. A range of ketamine dose was used. |
Author Commentary:
Following a literature search only one RCT was identified indicating a paucity of research exists examining the effects of nebulized ketamine on asthma exacerbation treatment. While the RCT by Farshadfar et al demonstrated potential benefit with nebulized ketamine, it did not lead to significantly better treatment outcomes than was provided by existing second-line treatment (intravenous magnesium). Therefore, more robust studies are needed to make definitive recommendations regarding nebulized ketamine use in the treatment of severe asthma exacerbations.
Bottom Line:
Insufficient evidence exists to recommend the routine use of nebulized ketamine in the treatment of severe asthma exacerbations.
References:
- Farshadfar, K., Sohooli, M., Shekouhi, R., Taherinya, A., Qorbani, M., & Rezaei-Kojani, M. . The effects of nebulized ketamine and intravenous magnesium sulfate on corticosteroid resistant asthma exacerbation; a randomized clinical trial