Ketamine for agitation
Ketamine as a first-line treatment for severely agitated emergency department patients. J Riddell et al. American Journal of Emergency. 2017 Feb 13. pii: S0735-6757(17)30114-6.
Rapid control of the severely agitated person in the ED is important for both patient and staff safety. Benzodiazepines and haloperidol are commonly used first line agents that have draw backs. Ketamine may be a faster, more reliable option, and has been shown to be effective in the prehospital setting.
A single-center, prospective, observational study was conducted at an urban academic institution. Adult patients with severe agitation were enrolled and level of agitation was evaluated. Patients were assessed using a 6-point agitation both before and then 5, 10 and 15 minutes sedation. Chemical sedation used was determined by the treating physician and agents studied were ketamine, midazolam, lorazepam, haloperidol or a combination of lorazepam plus haloperidol. The primary objective of the study was to determine if patients receiving ketamine had faster time to agitation reduction as compared to current first line agents. Secondary outcomes were abstracted retrospectively and compared rates of adverse events, vital sign changes, and need for medication redosing.
98 patient were enrolled in the study. The five treatment groups were comparable with the exception of having a low mean age in the ketamine group. Medication as administered IV, IM, or IN and dosages varied, but were frequently lower than the standard recommended dose. The study found that the groups all had similar initial agitation scores, but at 5, 10 and 15 minutes the ketamine group showed a statistically significant reduction in agitation (p = 0.001, p ≤ 0.001, p = 0.032) as compared to the other treatment modalities. When it came to physician determination of “time to control,” there was no statistical difference between the groups. In terms of secondary outcomes, the study was underpowered to appropriately assess these endpoints, but no significant difference was seen in terms of need for medication redosing, vital signs changes or other adverse outcomes.
Ketamine is proving to be an effective and safe medication for sedation of the acutely agitated patient. While more studies are needed to determine the most appropriate dosing (positive results with lower IM and IV dosing of ketamine seen in this study), use of ketamine as a first-line agent for agitation seems a reasonable alternative to benzos and haldol.