2. Outline Historical Perspectives. Why do we use epidural analgesia? What is epidural analgesia? You want me to stick that needle where? Medications and additives How is epidural analgesia different in children? What are side-effects of epidural analgesia? Or, at least, what goes wrong in Great Britain What to do about side effects

3. Historical Perspective 1,2 1885: J. L. Corning injects cocaine “near” spinal vessels; probably epidural 1901: Sicard and Cathelin popularize sacral caudal anesthesia 1921: Pages popularizes lumbar epidural anesthesia 1932-3: Gutierrez and Soresi use “hanging drop” 1939: Forestier, Dogliotti describe “loss of resistance”

4. Why do we use epidural anesthesia? Family Practitioner Notes 70% chance of success Currently accepting appointments

5. Why do we use epidural anesthesia? Cochrane Review 2006 2 : 13 RCT’s involving 1224 patients undergoing open AAA repair Epidural group demonstrated Lower subjective pain scores on movement (up to day 3) Decreased length of intubation and mechanical ventilation Decreased incidence of cardiovascular complication, acute respiratory failure, gastrointestinal complication, and renal insufficiency

6. Why do we use epidural anesthesia? Archives of Surgery, 2008 3 : 58 RCT’s, 5904 patients with systemic or epidural anesthesia lasting 24 hours or longer Epidural group demonstrated Decreased odds of pneumonia overall (OR 0.54) Weaker effect vs. PCA’s (OR 0.64) compared with non-patient- controlled anesthesia (OR 0.30) On the other hand: Also reported was an increased rate of hypotension, urinary retention, and pruritis

7. What is epidural analgesia? Insertion of anesthetic within a potential space Penetration of the supraspinous ligament, interspinous ligament, and ligamentum flavum, until “loss of resistance” is noted

8. What is epidural analgesia? Medications Generally Bupivicaine, or similar longer lasting local anesthetic Ropivicaine and levobupivicaine are S(-) enatiomers that preferentially block sensory fibers RCT involving 141 children compared bupivicaine and levobupivicaine at 0.2 and 0.25% concentrations 4 Demonstrated no significant difference in efficacy or rate of side effects

9. What is epidural analgesia? Additives Clonidine α2-agonist that prevents nociceptive neurotransmitter release at the dorsal horn of the spinal cord Can cause hypotension, bradycarida, and sedation Ketamine Prolongs analgesic effect of local anesthetics Can produce apoptotic neurodegneration in the developing brain Not commonly used

10. How is epidural analgesia different in children? 5 Anatomic differences Thinner myelin sheaths – can require less anesthetic Cord lengths – cord ends at L3 and the dura ends at S3 Can injure the spinal cord at lower levels than in adults Lack of lumbar lordosis Provides a wider interval for insertion of the needle Physiologic Differences Dissimilar hemodynamic response to sympathetic blockade Children up to 8 years old demonstrate little or no change in BP even with high thoracic block

11. What are side effects of epidural analgesia?

12. What are side-effects of epidural analgesia? National Pediatric Epidural Audit 7 Prospective audit of 10,633 patients in Great Britain and Ireland Complications total of 56 Infection (28) Ranging from meningismus and abscess (n = 1 and 2, respectively) to cellulitis Nerve Injury (6) Headache (6) Inadvertent spinal anesthetic (2) Drug Errors (13) Local anesthetic toxicity (1)

13. What are side-effects of epidural analgesia? Hypotension Randomized trial in patients undergoing THA 8 18% of patients undergoing epidural block demonstrated hypotension defined as >30% decrease in SBP Hematoma Uncommon in the absence of risk factors, but case reports exist

14. Treatment of side effects? Infection: Antibiotics Hypotension: Decrease epidural rate, fluids Hematoma: Treat coagulopathy, likely spontaneous resolution Headache: symptomatic relief, supine positioning, dural puncture may require repair Inadvertent spinal: reposition catheter or discontinue use

15. References 1. Butterworth, John. “Regional Anesthesia for Cardiac Surgery.” Online. Internet. http://www.wfubmc.edu/anesthesia/ (Accessed 11/4/09) http://www.wfubmc.edu/anesthesia/ 2. Frolich MA, Caton D. “Pioneers in Epidural Needle Design.” Anesthesia & Analgesia. 2001; 93: 215- 220. 3. Nishimori M, Ballantyne JC, Low JH. “Epidural pain relief versus systemic opioid-based pain relief for abdominal aortic surgery.” Cochrane Database Systemic Review. 2006, Jul 19. 4. Popping DM, Elia N, Marret E, et al. “Protective effects of epidural analgesia on pulmonary complications after abdominal and throracic surgery: a meta-analysis.” Archives of Surgery. 2008; 143(10): 990-999. 5. Ingelmo P, Locatelli BG, Frawley G, et al. “The optimum initial pediatric epidural bolus: a comparison of four local anesthetic solutions.” Pediatric Anesthesia. 2007; 17: 1166-1175. 6. Ivani G, Mosstti V. “Regional Anesthesia for Postoperative Pain Control in Children: Focuse on Continuous Central and Perineural Infusions.” Pediatric Drugs. 2008; 10(2): 107-114. 7. Llewellyn N, Moriarty A. “The National Pediatric Epidural Audit.” Pediatric Anesthesia. 2007; 17: 520-533. 8. Borghi B, Casati A, Iuroio S. “Frequency of hypotension and bradycardia during general anesthesia, epidural anesthesia, or integrated epidural-general anesthesia for total hip replacement.” Journal of Clinical Anesthesia. 2002; 14(2): 102-106.