Samina Ismail Associate Professor Aga Khan University Karachi, Pakistan

1. Challenges faced in managing post-operative caesarean section pain. SaminaIsmail Associate Professor Aga Khan University Karachi, Pakistan

4. Road Map • Challenges faced in managing post-operative caesarean section pain. • The National Institute for Health and Clinical Excellence (NICE) Guidelines-2011: • Intrathecal opioids • PCA • Multimodal analgesia • Reaching the standards • Way forward

5. Managing post-operative caesarean section pain

6. Striking a balance!! Prevention of side effects. Harmful effects on the fetus. Providing effective analgesia/ anesthesia

7. If inadequately controlled…….. Subjective discomfort Neuro-endocrine response Delayed restoration of function Increasing the risk of Thromboembolism Inability to take care & breast feed the newborn Risk of persistent pain & depression de BritoCancado 2012 Marcus HE et al 2011 Eisenach JC et at ,Pain 2008;140:87-94

8. Further challenges Unavailability of drugs & expertise. Inter-individual variability in pain response to same noxious stimuli.

9. Inter-individual variability in “Pain Perception” Predicting the Pain • Pain models • Genetic testing

10. Pain models Pain models are valuable since they generate a painful stimulus under controlled and standardized conditions. Allows for an essentially unbiased assessment of an exceptionally subjective experience. Clinical application of the pressure pain model has been validated for evaluating pain sensitivity. Hsu Y, Somma et al .Predicting postoperative pain by preoperative pressure pain assessment. Anesthesiology 2005;103:613-8. Kinser AM et al.Reliability and validity of a pressure algometer. J Strength Cond Res 2009;23:312-4.   

11. Quantitative sensory testing (QST), defined as quantifiable mechanical (pressure, punctuate, vibratory, and light touch), thermal (cold pain, cool, warm, and heat pain) or electrical stimuli, was used in nearly all the studies (5 CS/14 studies) This review demonstrates that QST assessments may predict up to 54% of the variance in postoperative pain experience, particularly after cesarean section, and in development of persistent postsurgical pain

12. Genetic test to predict to individualize postoperative Pain therapy-2010 Landau et al tried to individualize anaesthetic care during caesarean section by identifying some genetic polymorphisms. It was concluded that genetic test may become useful bedside screening test in predicting individual postoperative pain therapy & development of chronic pain

13. Recommended Guidelines

14. The National Institute for Health and Clinical Excellence (NICE) Guidelines-2011

15. Section 9.2 of The National Institute for Health and Clinical Excellence (NICE) Guidelines • Intrathecal/epidural opioids: Morphine/diamorphine • PCA with morphine • Multimodal analgesia: • NSAIDS • Wound infilteration

16. (NICE) Guideline: • Intrathecal/epidural opioids

17. Spinal cord selectivity of neuraxial opioid in the treatment of acute postoperative pain Morphine & Diamorphine commonly used intrathecal opioids for caesarean section

18. Monitoring after intrathecal opioids NICE guidelines on caesarean section, suggested minimum hourly observations of: Respiratory rate , sedation & pain scores for at least • 12 h for diamorphine • 24 h for morphine

19. Conclusion • There is evidence that intrathecal morphine produced a clinically relevant reduction in postoperative pain and analgesic consumption • They recommended 0.1 mg morphine as the drug and dose of choice. • However, for every 100 • women receiving 0.1 mg intrathecal morphine added to a spinal anesthetic: • 43 patients will experience pruritus, • 10 will experience nausea • 12 will experience vomiting

20. Significant decrease in vomiting but no effect on nausea

21. 2. Patient controlled Analgesia (PCA)

22. Patient controlled analgesia (PCA) The limitation of individual patient’s variability and fluctuating blood level of analgesic is overcome to some extent by the use of PCA Has become a gold standard for acute pain management since it was introduced in June 1984. Works on the Principal of “WYNIWYG”: what you need is what you get. More recent development in PCA includes intranasal &regional techniques.

23. Despite being less efficacious than neuraxial administration, patient satisfaction scores are highest with IV-PCAB.M. Block, S.S. Liu, A.J. Rowlingson, A.R. Cowan, J.A. Cowan and C.L. Wu, Efficacy of postoperative epidural analgesia: a meta-analysis, JAMA290 (2003): 2455–63.G.E. Larijani, I. Sharaf, D.P. Warshal, A. Marr, I. Gratz and M.E. Goldberg, Pain evaluation in patients receiving intravenous patient-controlled analgesia after surgery, Pharmacotherapy 25 (2005) :1168–73.

24. S Ismail et al Postoperative Analgesia Following Caesarean Section: Comparison of Intravenous Patient Controlled Analgesia with Conventional Continuous Infusion.   We found better pain score at 6, 12 and 24 hours postoperatively , less need for rescue analgesia and better pain satisfaction.

25. 3-Multimodal analgesia

26. Multimodal analgesia • Co-analgesic/ adjuvant drugs. • Nerve block and wound infilteration

27. “Goals” of multimodal analgesia • obtain synergistic or additive analgesia with each drug with different mechanisms of action • fewer side effects by combining lesser amounts of each drug.

28. Co-analgesic/ adjuvant drugs

29. Non-steroidal anti-inflammatory drugs (NSAIDs) “Anti-inflammatory and antipyretic properties” Reduce visceral pain originating from the uterus, complementing the somatic wound pain relief from the opioid.

30. NSAIDs • potentiate opioid effect • decrease opioid consumption and reduce side effects C.H. Wilder-Smith, L. Hill, R.A. Dyer, G. Torr and E. Coetzee, Postoperative sensitization and pain after Cesarean delivery and the effects of single im doses of tramadol and diclofenac alone and in combination, Anesth Analg 97 (2003) : 526–33. J.L. Lowder, D.P. Shackelford, D. Holbert and T.M. Beste, A randomized, controlled trial to compare ketorolactromethamine versus placebo after cesarean section to reduce pain and narcotic usage, Am J Obstet Gynecol 189 (2003) : 1559–1562.

31. Acetaminophen - useful alternative

32. CONCLUSION: Both diclofenac-tramadol and diclofenac-acetaminophen combinations can achieve satisfactory post-operative pain control in women undergoing caesarean section. The diclofenac-tramadol combination was overall more efficacious but associated with higher incidence of post-operative nausea

33. A newer COX-2 inhibitor, (parecoxib) was compared with Ketorolac combined with morphine on IV-PCA in post CS pain management.It was found to have efficacy equating Ketorolac with PCA morphine for an opioid sparing effect .

34. Anesth Analg 2011 Preoperative gabapentin 600mg in the setting of multimodal analgesia reduces post CS pain and increase maternal satisfaction 19% of the patient had severe sedation as compared to 0% in the controlled group no difference in the APGAR score or umbilical artery pH

35.  Low-dose S-ketamine, administered by i.m. bolus and continuous i.v. infusion, reduced morphine consumption and prolonged postoperative analgesia after cesarean section with spinal anesthesia. Only minor side effects were detected

37. Nerve block and wound infiltration

38. The Cochrane database of 2009 indicates that local analgesia infiltration and abdominal nerve block as adjunct to regional analgesia and general anaesthesia are of benefit in caesarean section by reducing opioid consumption.

39. Wound infiltration and/or ilioinguinal nerve block Ranta et al. report the subfascial catheter administration of levobupivacaine following caesarean delivery to be a useful and safe component of multimodal pain management and a viable alternative to epidural analgesia

40. Regional Anesthesia and Pain MedicineIssue: Volume 34(6), November/December 2009, pp 586-589

41. Patient-controlled i.v. morphine without long-acting intrathecal opioids was used for postoperative pain management.Conclusions The US-guided TAP block reduces morphine requirements after Caesarean delivery when used as a component of a multimodal analgesic regimen.

42. Nine studies were included Conclusion Transversus abdominis plane block significantly improved postoperative analgesia in women undergoing CD who did not receive ITM but showed no improvement in those who received ITM. Intrathecal morphine was associated with improved analgesia compared with TAP block alone at the expense of an increased incidence of side effects.

43. Therefore TAP block can be a better option for patients not receiving long acting neuraxial opioids.

44. PERIPHERAL N- BLOCK (2014) PERIPHERAL N- BLOCK (2014)

46. Royal College of Anaethetist (RCoA) The standard suggests that > 90% of women should score their worst pain as < 3 on VAS of 0-10.

47. Every health care facility should have a goal to generate uniformly low pain scores of “< 3 out of 10 both at rest & movement”

48. Have we reached the standard?

50. S Ismail et al-Observational study to assess the effectiveness of postoperative pain management of patients undergoing elective caesarean section Percentage of patients having mild, moderate and severe pain scores at rest and movement The analysis of pain at rest: VAS of 4-6 in 9.5% VAS of7-10 in 0.8% The analysis of pain at movement: VAS 4-6 in 33.1% VAS 7-10 in 6.8% of patients. Patient satisfaction>90%