Ketamine sedation for psychostimulant intoxication
Take two of these and call me in the morning
HI there folks. ON Twitter this week there was a discussion that keeps resurfacing on concerns of best sedation for agitated patients with psychostimulant intoxication.
The usual fears of ketamine sedation re-emerged , citing that ketamine may worsen cardiovascular effects of stimulant toxicity and/or magnify delirium.
Folks who dont have droperidol, often say that midazolam ( I call it midazoslap or midazoslam, depending on dosing) is the ideal agent for sedation for this patient group.
I am not going to say that midazolam is not effective. I am going to say it can be too effective . So effective that it will stop agitation completely by inducing apnoea and airway loss. It doesnt last long and so repeated dosing is often needed. THis then can lead to accumulation of the drug and the threshold for respiratory complications can get quickly reached.
But this article is not about saying ketamine is better than midazolam nor vice versa. THis is about reviewing the safety and efficacy of ketamine sedation in the psychostimulant intoxicated patient, in case you get a situation that may be assisted with ketamine and you want to know the evidence base and current practice globally.
One of the very first case reports of prehospital ketamine sedation of a stimulant intoxicated patient was from Hennepin County, here.
A total of 450mg IM ketamine was administered to a cocaine intoxicated suicidal patient trying to jump of a bridge. The patient was safely sedated and extricated , whereby medical assessment displayed stable vital signs and transport to ER was undertaken.
IN recent years, synthetic stimulant street drug called FLakka, has been often treated with ketamine sedation for agitation control and many regard it as best agent when benzodiazepines have failed or the agitation is highly violent.
IN the latest EM based study of ketamine sedation for acutely agitated patients, Australian researchers found that 14% of study patients had psychostimulant intoxication as primary diagnosis
Ketamine as Rescue Treatment for Difficult-to-Sedate Severe Acute Behavioral Disturbance in the Emergency Department
IN this small case series, ketamine sedation was safe and effective in majority of patients who had failed first line sedation with droperidol and/or benzodiazepines. Of the 3 complications of ketamine sedation, they were vomiting and respiratory complications and no cardiovascular complications occurred/needed treatment.
Looking at other areas of psychopharmcological research, this study from 2005, comparing amphetamine and ketamine combinations, it can be seen that pulse rate doesnt vary significantly with the combination and the increase in blood pressure is not significantly additive.
In fact in this study the sedative effect of ketamine appeared to counteract the stimulant effect of amphetamine.
Conclusion : I use ketamine sedation in cases of psychostimulant intoxication as a second line agent, after droperidol sedation has not achieved sufficient effect. In the highly violent patient, I choose ketamine sedation as first line to establish rapid control with relative safety profile.