ESKetamine Low-dose vs Ketamine Low-dose for Severe Acute Pain in Emergency Units, Comparison of PsychodyslEptic Effects
Status:
RECRUITING
Trial end date:
2026-12-01
Target enrollment:
Participant gender:
Summary
Almost 30% of painful patients in emergency departments (ED) describe their pain as severe (i.e. a Verbal Numerical Rating Score VNRS 6 on a scale ranging from 0 to 10). The management of such severe pain needs to be rapid and safe, and for this purpose intravenous (IV) morphine titration is still the gold-standard. However, morphine titration takes up considerable caregiver time, as patients need to be monitored and treated progressively with small quantities of morphine every 5 minutes until analgesia. This is sometimes difficult to reconcile with a saturating flow of patients, and overcrowding in ED is proven to significantly delay time-to-analgesia, and even lead to deleterious under-treatment. Finally, the opioid crisis is a major concern, explaining why strategies are being advocated to develop other ways of managing severe acute pain in the ED and to limit the use of opioids.
Recent studies show that ketamine administered in small IV doses ("low-dose" ketamine LDK: 0.2 to 0.3 mg/kg) possesses potent analgesic activity as well as interesting anti-hyperalgesic and anti-allodynic properties. Compared with morphine, LDK does not induce respiratory depression, but can sometimes induce disturbing psychodysleptic effects. These may include a sensation of unreality, fatigue, anxiety, dizziness or hallucinations. According to studies, 30-80% of LDK-treated patients experience psychodysleptic effects. However, two recent studies suggest that slow IV injections of LDK (over 10 minutes) may improve patient tolerance, although these slow infusions do not totally reduce this discomfort.
Pharmacologically, ketamine is a racemic mixture of 2 isomers: esketamine S(+), which is dextrorotatory, and arketamine R(-), which is levorotatory. In recent years, a new formulation containing only esketamine has been made available to hospitals in some northern European countries, and more recently in France. Esketamine appears to have twice the analgesic efficacy of racemic ketamine, and studies on healthy volunteers or in peri-operative settings suggest that it is also better tolerated psychologically than ketamine. For the moment, however, scientific data are lacking, and no comparative trial has yet been conducted in the ED setting. The investigators plan to conduct in their ED a prospective, single-center, randomized, double-blind study aiming to compare the tolerance and efficacy of esketamine versus racemic LDK in patients presenting with severe acute pain (VNRS 6/10).