Multimodal approach in acute post operative pain.pptx

Pain

1. 3D look to acute post operative pain Dr. Eltayeb Elkhabir MD anesthesia university of Khartoum PG/Dip PM/AAFIP Cardiff university Consultant anesthesiologist and pain management

2. Pain management: What is new? Newer developments in understanding the pathophysiology of pain Newer concepts of analgesic therapy Newer drugs to manage pain Interventional Pain Management to diagnose & treat pain

3. Magnitude of the problem Postoperative pain or postsurgical pain can be considered a form of acute nociceptive pain with localized inflammatory responses resulting from surgical tissue damage Nociceptive pain is pain that is proportionate to the degree of actual tissue damage.

4. Magnitude of the problem Postoperative pain can be neuropathic or neurogenic and can become chronic if it involves inflammation or injury to a nerve, which can occur during surgical procedures such as amputation, hernia repair, hand surgery, or thoracotomy .

5. Review of recent studies It is estimated that about 80% of patients experience pain after surgery, of which 86% have moderate, severe, or extreme pain. In spite of considerable progress in postoperative analgesia, recent studies show that adequate pain relief remains elusive for a significant fraction of hospitalized surgical patients

6. Targets It is important for health care professionals to have an understanding of the anatomy and physiology of postoperative pain to improve outcomes in managing postoperative pain.

7. The anatomy of postoperative pain

8. MECHANISMS OF POSTOPERATIVE PAIN Peripheral and Central Sensitization in Postoperative Pain

9. Important massage Understanding the anatomy of acute an neuropathic postoperative pain requires knowledge of the underlying neuronal plasticity at the levels of the nociceptive neurons spinal cord and brain.

10. Modulatory effects at the nociceptor , SMP, central sensitization, and alterations in ascending/descending CNS pathways are all involved in the perception of pain as well as the related pain motivations andthen act on other glia and spinal neurons. The released chemicals, including pro-inflammatory cytokines (e.g., interleukin-1 and TNF-a), have been shown to be critical mediators of allodynia

11. Physiology & pharmacological management of postoperative pain

12. Pain pathway and modulation 1 Descending inhibitory controls / Diffuse noxious inhibitory controls Interpretation in cerebral cortex: pain Stimulation of nociceptors (A  and C fibers) / Release of neurotransmitters and neuromodulators (i.e. PG) 1. Adapted from: Bonica JJ. Postoperative pain. In Bonica JJ, ed. The management of pain. Philadelphia: Lea and Febiger;1990:461-80. Release of serotonin, noradrenalin and enkephalins at spinal level Activation of serotoninergic and noradrenergic pathways Injury Ascending nociceptive pathways

13. Modes of action of analgesics 1,2,3,4 1 . D’Amours RH et al. JOSPT 1996;24(4):227-36. 2. Piguet V et al. Eur J Clin Pharmacol 1998;53:321-4. 3. Pini LA et al. JPET 1997;280(2):934-40. 4. Chandrasekharan NV et al. PNAS 2002;99(21):13926-31. Opioids  Activation of opioid receptors Paracetamol  Inhibition of central Cox-3 (?) (Inhibition of PG synthesis ) Paracetamol  Interaction with serotoninergic descending inhibitory pathway NSAIDs / Coxibs  Inhibition of peripheral and central Cox-1 / Cox-2 (Inhibition of PG synthesis )

14. Multimodal and Preemptive Approaches to Managing Postoperative Pain

15. The concept and benefits of balanced analgesia “The rationale for multimodal analgesia is achievement of sufficient analgesia due to additive or synergistic effects between different analgesics, with concomitant reduction of side effects , due to resulting lower doses of analgesics and differences in side -effect profiles” 1. Kehlet H et al. Anesth Analg 1993;77:1048-56.

16. Single drug/ like single flower Multimodal analgesic/ like gift basket

17. Goal To provide patients with a level of pain control that allows them to actively participate in recovery This level will be individual to each patient To minimize nausea and vomiting To minimize other side effects of analgesics Sedation Ileus Weakness Hypotension

18. Objectives/Discussion Topics Appropriate assessment of acute pain Concept of multi-modal analgesia Indications and side effects of analgesics How to rationally prescribe opioids side effects and complications of opioids Special populations ie elderly, opioid tolerant Neuraxial /regional analgesia side effects and complications of neuraxial analgesia interaction of various anticoagulant medications and neuraxial analgesia

19. Why all the fuss? Pain is a miserable experience Pain increases sympathetic output Increases myocardial oxygen demand Increases BP, HR Pain limits mobility Increases risk for DVT/PE Increases risk for pneumonia, atelectasis secondary to splinting

20. Assessment Intensity Location Onset Duration Radiation Exacerbation Alleviation

21. How do we do it? Multimodal analgesia: Several analgesics with different mechanisms of action, each working at different sites in the nervous system Acetaminophen Non-steroidal anti-inflammatory drugs (NSAIDs) Opioids Anticonvulsants Antidepressants Local anaesthetics NMDA Antagonists Non-pharmacologic methods

22. OPIOIDS Efficacy is limited by Side-Effects The harder we “push” with single mode analgesia, the greater the degree of side-effects Analgesia Side-effects

23. Multimodal Analgesia Lower doses of each drug can be used therefore minimizing side effects With the multimodal analgesic approach there is additive or even synergistic analgesia, while the side-effects profiles are different and of small degree (Pasero & Stannard, 2012) . Analgesia Side-effects

24. Pain: Clinical Types Nociceptive pain Transient pain in response to noxious stimuli Inflammatory pain Spontaneous pain and hypersensitivity to pain in response to tissue damage and inflammation Neuropathic pain Spontaneous pain and hypersensitivity to pain in association with damage to or a lesion of the nervous system Woolf. Ann Intern Med. 2004;140:441-451.

25. Perception Modulation Transduction Transmission Reuben et al. J Bone Joint Surg. 2000;82:1754-1766. Postoperative pain is nociceptive

26. Consequences of Unrelieved Pain Myocardial ischemia Increased sympathetic activity Myocardial O 2 consumption  GI effects Splinting, shallow breathing Increased catabolic demands Anxiety and fear Peripheral/ central sensitization GI motility  Atelectasis, hypoxemia, hypercarbia Poor wound healing/muscle breakdown Sleeplessness, helplessness Available drugs Delayed recovery Pneumonia Weakness and impaired rehabilitation Psycho- logical Chronic pain Acute Pain Courtesy of Sunil J Panchal , MD

27. Guidelines for optimising POP management 1,2,3,4,5,6 Adequate and thorough patient information 2,3,4,5,6 Use of written protocols 1,3,4,5,6 Regular assessment of pain intensity 1,2,3,4,5,6 Adequate medical and nursing staff training 1,3,4,5,6 Use of balanced analgesia, PCA, and epidural drug administration 1,2,3,4,5,6 1. The Royal College of Surgeons of England and the College of Anaesthetists. Commission on the provision of surgical services, report of the working party on pain after surgery. London, UK, HMSO.1990. 2. Agency for Health Care Policy and Research, Public Health Service, US Department of Health and Human Services. Acute Pain Management in Adults: Operative Procedures. Quick Reference Guide for Clinicians. AHCPR Pub. No. 92-0019. Rockville, MD.1992. 3. International Association for the Study of Pain, Management of acute pain: a practical guide. In: Ready LB, Edwards WT, eds. Seattle, 1992. 4. Wulf H et al. Die Behandlung akuter perioperativer und posttraumatischer Schmerzen Empfehlungen einer interdisziplinaeren Expertenkommision. G. Thieme, Stuttgart, New York. 1997. 5. EuroPain. European Minimum Standards for the Management of Postoperative Pain.1998. 6. SFAR. Conférence de consensus. Prise en charge de la douleur postopératoire chez l’adulte et l’enfant. Ann Fr Anesth Réanim 1998;17:445-61.

28. Pain pathway and modulation 1 Descending inhibitory controls / Diffuse noxious inhibitory controls Interpretation in cerebral cortex: pain Stimulation of nociceptors (A  and C fibers) / Release of neurotransmitters and neuromodulators (i.e. PG) 1. Adapted from: Bonica JJ. Postoperative pain. In Bonica JJ, ed. The management of pain. Philadelphia: Lea and Febiger;1990:461-80. Release of serotonin, noradrenalin and enkephalins at spinal level Activation of serotoninergic and noradrenergic pathways Injury Ascending nociceptive pathways

29. Modes of action of analgesics 1,2,3,4 1 . D’Amours RH et al. JOSPT 1996;24(4):227-36. 2. Piguet V et al. Eur J Clin Pharmacol 1998;53:321-4. 3. Pini LA et al. JPET 1997;280(2):934-40. 4. Chandrasekharan NV et al. PNAS 2002;99(21):13926-31. Opioids  Activation of opioid receptors Paracetamol  Inhibition of central Cox-3 (?) (Inhibition of PG synthesis ) Paracetamol  Interaction with serotoninergic descending inhibitory pathway NSAIDs / Coxibs  Inhibition of peripheral and central Cox-1 / Cox-2 (Inhibition of PG synthesis )

30. The concept and benefits of balanced analgesia “The rationale for multimodal analgesia is achievement of sufficient analgesia due to additive or synergistic effects between different analgesics, with concomitant reduction of side effects , due to resulting lower doses of analgesics and differences in side -effect profiles” 1. Kehlet H et al. Anesth Analg 1993;77:1048-56.

31. Patients’ Preferences for Acute Pain Treatment Pain Control 41% Setting and Route of Administration 12% Side-Effect Severity 19% Side-Effect Type 28% Patients prefer avoiding side effects over complete pain control 47% Gan et al. Br J Anaesth. 2004;92:681-688.

32. Proportion of Patients Experiencing Adverse Events Gan et al. Br J Anaesth . 2004;92:1-8. Adverse Event (AE) Total % Constipation 50 Mental cloudiness/dizziness 82 Itching 54 Nightmares/hallucinations 32 Mood changes/alterations 34 Nausea 70 Sleep disorders 48 Vomiting 32

33. Preventive Multimodal Analgesia Significant improvement in Pain reduction Opioid use Opioid-related AEs Recovery or day ward length of stay Unplanned admission to the hospital Reuben et al. Acute Pain. 2004;6:87-93.

34. “Real World”: Multimodal Analgesia Reduced doses Improved pain relief Reduce severity of AEs Earlier discharge Decreased costs Opioids NSAIDs, coxibs, paracetamol, nerve blocks Potentiation Kehlet et al. Anesth Analg. 1993;77:1048-1056 (B).

35. Intravenous agents for multimodal analgesia

36. IV morphine Intermittent IV bolus doses Is best method for acute pain Optimal doses and dose intervals not established 2-3 mg doses at 5 minute intervals appears effective Continuous infusion Compared with PCA there is a 5-fold increase in respiratory depression

37. IV paracetamol - premise “Is more effective & has a faster onset than oral paracetamol”

38. Means of pain intensity differences (VAS) Onset of action is fast and effective – within 5 minutes Sindet-Pedersen S. Br Jr Anesth 2005. 94 (5): 642-8

39. Epidural Infusions Used for major surgery ie. oncologic TAH BSO, thoracotomy Ideally placed pre-operatively and used in combination with a GA for surgery and continued ~ 2 days Usually patient is tolerating diet and ambulation to chair when epidural is D/C

40. Ideal Epidural Infusions When placed at the level of the incision and with a constant infusion of LA and opioid: Minimal or no pain at all, particularly with movement No motor block Can ambulate Speedier return of bowel function With more LA and less opioid –Cochrane review 2003 Less nausea Less sedation Less delerium Do not require supplemental IV opioids and associated side effects Less pulmonary complications Quicker extubation, better oxygen saturation, less pneumonia

41. Pain in the obstetric patient Anatomy of Pain Transmission Common to all birth processes are two discreet sources of painful stimulation. The first is a result of the rhythmic uterine contractions The second from the passage of the fetus.

42. While most women describe significant pain from one of these processes, the peak of labor pain is usually felt during the period of transition, when both stimuli are at their greatest

43. Physiology of Labor Pain Similar to other intense acute pain syndromes childbirth creates significant physiologic responses in both mother and child. The painful stimulation affects directly or indirectly most major organ systems in the body.