1. Pain Management Olivier Cuignet, MD (responsible) Gregory Minguet, MD Jan Muller, MD Kirsten Colpaert, MD

2. pre-hospital care (su)fenta or piritramide iv Treat as fast and as strong as possible to avoid mechanisms to be discussed What kind of Burn patients ? Opioids and FLUID CREEP Burns 2004; 30(6):583-90.

3. Pre-hospital care of burn patient (su)fenta or piritramide iv Treat as fast and as strong as possible to avoid mechanisms to be discussed Opioids and FLUID CREEP Local cooling and water gel Treat the pain fast and strong with the minimum opioids needed : « Cocktail de Djibouti » (Ketamine / Bzd / Atropine iv) What kind of Burn patients ?

4. Aims Pain characteristics and analgesics Lessons learned from our 6 years experience New approach of burn pain nociceptive hyperalgesia opioid-induced hyperalgesia New strategy based on a new pain assessment

5. Pain Characteristics dressing changes, post-operative periods, physiotherapy nursing care Procedural Pain (PP): repetitive frequent excrutiating Burn Background Pain (BgP): constantbreakthrough pain excruciatingsound easily defineddiffuse responds well to therapeuticsincreased therapeutic needs Wind-ups : Complicated Pain (CP)

6. Pain control strategy : WHO Scale STEP 1 :Paracetamol? NSAID (Taradyl/Brufen) “10 mg” STEP 2 : Tramadol 10 mg Codeine 6.6 mg STEP 3 : Piritramide1.25 mg Hydromorphone0.134 mg Morphine1 mg Sufentanyl0.001 mg

7. Lessons learned from 6 years of Pain Management... Pain assessment is mandatory to meet patient’s need. Appropriate Burn Pain therapy requires huge doses of morphine equivalent

8. Huge doses Opioids : burns are very painful burn pain is a long-term process burn pain is more and more painful opioid become less efficient over time Burn Pain therapy

9. Background Pain Huge doses morphine-equivalent: Intensive Care : iv 100 à 168 mg/24h (sufenta) + bath Medium Care : oral 65 à 200 mg /24h (tramadol + MSDirect +/- hydromorphone) Potential problems: Fluid creep Burns 2004; 30(6):583-90. Immunological Am J Ther 2004; 11(5):354-65. Endocrine J Clin Endocrinol Metab 2000; 85(6):2215-22. Tolerance Anasthesiol Intensivmed 2003; 38(1):14-26. Hyperalgesia J Neurobiol 2004; 6(1):126-48.

10. Background Pain How to reduce high doses of morphine-equivalent? Avoid the early hyperalgesia due to burn and its inflammatory response Avoid opioid tolerance / opioid hyperalgesia by limiting the initial opioid doses New comprehensive physio-pathology of burn pain

11. Physio-pathology of burn pain. Three periods of Hyperalgesia: Activation (receptors recruitment) Modulation (NMDA, receptors phosphorylation) Modification (new genes, apoptosis) Three levels of Burn-induced Hyperalgesia: Peripheral (receptors/ nerves ending) Spinal (dorsal horn) Supra-spinal (brainstem, thalamus, cortex) time Non reversibility

12. Modified from O.H Wilder Smith. Anesthesiology 104, 2006; 601-7 Burn

13. Treat the pain as soon as possible (before activation of pain amplification mechanisms) Treat the pain as completely as possible at the periphery at the spinal level at the supra-spinal level Physio-pathology of burn pain.

14. Treat the pain as soon as possible (before pain amplification mechanisms activated) Treat the pain as completely as possible at the periphery at the spinal level at the supra-spinal level Treat the pain with as few opioids as possible to avoid opioid-induced hyperalgesia to avoid opioid-tolerance Physio-pathology of burn pain.

15. Modified from O.H Wilder Smith. Anesthesiology 104, 2006; 601-7

16. Pain Control Strategy Peripheral hyperalgesia Hydro-colloids dressing, homografts, antiseptic ointments. Early excision Loco-regional anesthesia

17. Procedural Pain: post-operative Post-operative: loco-regional anesthesia for donor sites long-term opioid-sparing effects J Burn Care Rehabil. 2005 Sep-Oct;26(5):409-15

18. Pain Control Strategy Peripheral hyperalgesia Hydro-colloids dressing, homografts, antiseptic ointments. Early excision Loco-regional anesthesia Spinal and supraspinal hyperalgesia Anti-hyperalgesic drugs : kétamine, lidocaine, pregabalin Opioid-sparing agent : clonidine

19. Pain Control Strategy Gabapentin reduces opioid-consumption during and up to 3 weeks after its administration Burns. 2007 Feb;33(1):81-6

20. Pain Control Strategy Peripheral hyperalgesia Hydro-colloids dressing, homografts, antiseptic ointments. Early excision Loco-regional anesthesia Spinal and supraspinal hyperalgesia Anti-hyperalgesic drugs : kétamine, lidocaine, pregabalin Opioid-sparing agent : clonidine Opioid-induced hyperalgesia Assessment of hyperalgesia Judicious use of antihyperalgesic drugs (ketamine, lidocaine, pregabalin) Loco-regional anesthesia To do