Second life of Ketamine
- 1. S(+)-ketamine Treatment of Acute and Chronic Pain Marnix Sigtermans, MD Department of Anesthesiology
- 2. Chronic pain 19% of 46,394 respondents suffered pain for > 6 months 61 % were less able or unable to work 19% had lost their job becaus of pain 40% inadequate pain managment
- 3. Introduction: NMDA receptor antagonists Fencyclidine (PCP) was developed in 1926 NMDA-receptor antagonist Patented 1950 Anesthetic drug Side effects: hallucinogenic and neurotoxic Mid 1960’s ketamine, a new NMDA receptor antagonist Anesthetic drug Analgesic drug in anesthetic doses
- 4. Study objectives Characterization of efficacy and safety of ketamine in: Healthy volunteers CRPS patients Efficacy: analgesia (heat pain model) Safety: haemodynamic, psychomimetic effects
- 7. Does treatment with ketamine result in pain reduction in chronic pain patients? Complex Regional Pain Syndrome type 1 (posttraumatic dystrophy) Affects one or more extremities Standard pain management often inadequate Relative young patients Low quality of life and high costs for society
- 8. CRPS-1: International Association for the Study of Pain Complex Regional Pain Syndrome type 1 (sympathetic reflex dystrophy or posttraumatic dystrophy) Following a trauma Effects the extremities Pain and / or dystonic major complaints CRITERIA Presence of a noxious event, or immobilization Continuing pain, allodynia or hyperalgesia, (pain disproportionate) Edema, changes in skin blood flow and/or abnormal sudomotor activity No other explanation
- 9. CRPS type 1: example
- 11. Flowchart
- 12. Infusion period
- 13. Time course of analgetic effect P <0.001
- 14. Side effects during treatment No changes in: Blood pressure Liver function test P < 0.001 P = 0.004 P < 0.001 P = 0.78
- 15. CRPS acute and chronic pain Infusion phase Elimination phase
- 16. Results: n=12
- 18. CRPS Experimental pain CRPS pain
- 19. Conclusion Difference between onset and offset of analgetic action of ketamine Pharmacokinetic driven This suggests that apart from an analgesic effect ketamine displays a modulatory effect on the chronic pain process
- 20. Conclusion