Rapid tranquilization of the agitated patient in the emergency department: A systematic review and network meta-analysis

BACKGROUND

Safe and effective tranquilization of the acutely agitated patient is challenging, and head-to-head comparisons of medications are limited. We aimed to identify the most optimal agent(s) for rapid tranquilization of the severely agitated patient in the emergency department (ED).

METHODS

The protocol for systematic review was registered (PROSPERO; CRD42020212534). We searched MEDLINE, Embase, PsycINFO, and Cochrane Database/CENTRAL from inception to June 2, 2021. We limited studies to randomized controlled trials that enrolled adult ED patients with severe agitation and compared drugs for rapid tranquilization. Predetermined outcomes were: 1) Adequate sedation within 30 min (effectiveness), 2) Immediate, serious adverse event - cardiac arrest, ventricular tachydysrhythmia, endotracheal intubation, laryngospasm, hypoxemia, hypotension (safety), and 3) Time to adequate sedation (effect onset). We extracted data according to PRISMA-NMA and appraised trials using Cochrane RoB 2 tool. We performed Bayesian network meta-analysis (NMA) using a Markov Chain Monte Carlo method with random-effects model and vague prior distribution to calculate odds ratios with 95% credible intervals for dichotomous outcomes and frequentist NMA to calculate mean differences with 95% confidence intervals for continuous outcomes. We assessed confidence in results using CINeMA. We used surface under the cumulative ranking (SUCRA) curves to rank agent(s) for each outcome.

RESULTS

Eleven studies provided data for effectiveness (1142 patients) and safety (1147 patients). Data was insufficient for effect onset. The NMA found that ketamine (SUCRA = 93.0%) is most likely to have superior effectiveness; droperidol-midazolam (SUCRA = 78.8%) is most likely to be safest. There are concerns with study quality and imprecision. Quality of the point estimates varied for effectiveness but mostly rated "very low" for safety.

CONCLUSIONS

Available evidence suggests that ketamine and droperidol have intermediate effectiveness for rapid tranquilization of the severely agitated patient in the ED. There is insufficient evidence to definitively determine which agent(s) may be safest or fastest-acting. Further, direct-comparison study of ketamine and droperidol is recommended.

Kinematic Patterns in Horses Sedated With Low Doses of Detomidine: An Accelerometric Evaluation

Alpha-2-adrenergic drugs, such as detomidine, are commonly used to sedate lame horses during examination. However, the use of these drugs should be minimized, as they have numerous side-effects, like ataxia. Therefore, we wanted to test the effects, on the locomotor pattern, of low doses of detomidine (0.003 mg/kg). Six horses were sedated with 0.003 mg/kg of detomidine and compared with the same horses administered a saline solution. Using a triaxial accelerometer, data of kinetic, coordination and energetic locomotor parameters and the degree of sedation were collected. The effects were monitored for 60 minutes after treatment administration. No effects on coordination parameters were observed, but some kinetic and energetic parameters were significantly altered after detomidine administration compared to the saline group. These results show that administering low doses of detomidine to lame horses can be a useful sedative solution, ensuring a safe examination with lower side-effects.

Tranquilizer effect on the Lyapunov exponents of lame horses

Tranquilization of horses with acepromazine has been used to suppress erratic head movements and increase the accuracy of a lameness examination. Some equine clinicians believe that tranquilization with acepromazine will make lameness more evident by causing the horse to focus on adjusting its gait to avoid limb pain rather than its surroundings. The aim of this study was to investigate the effect of acepromazine on the Lyapunov exponents of lame horses. Ten lame horses were trotted in a straight line for a minimum of 25 strides. Kinematic data created by head movement were analyzed. Nonlinear analysis methods were applied to lame horse locomotion. The effect of acepromazine on the largest Lyapunov exponents of the lame horses were investigated. There was no statistically significant effect of acepromazine on the maximum value of Lyapunov exponents. The nonlinear dynamic methods can be used to analyze the gait in horses. Local stability of horse gait remains unchanged after the administration of acepromazine.