Pediatric Regional Anesthesia Caudal Anesthesia

1. Pediatric Regional AnesthesiaCaudal Anesthesia Amr Abouleish, MD, MBA University of Texas Medical Branch Galveston, Texas Title slide: need to center name remove body, bullet ?clip art Happy birthday BillTitle slide: need to center name remove body, bullet ?clip art Happy birthday Bill

2. under �why do..�: indications for RA and Combined RA+GA, contraindicationsunder �why do..�: indications for RA and Combined RA+GA, contraindications

3. How do children differ from adults? Psychologically and Parents Physiology Pharmacology Anatomy Overview of differences Discuss Psych and parents Parents concerns about placement and Comfort (during procedure) Will/Can Child tolerate placement and cooperate Will/CanChild lie still for procedure if GA only propofol infusions have been used to overcome as well as placement after GA given Overview of differences Discuss Psych and parents Parents concerns about placement and Comfort (during procedure) Will/Can Child tolerate placement and cooperate Will/CanChild lie still for procedure if GA only propofol infusions have been used to overcome as well as placement after GA given

4. Physiology Postoperative apnea in former premature infants Implications Immature CNS and BBB Regional alone decreases risk

5. Pharmacology General and Implications Distribution CSF Volume Total Body Water Protein Binding Clearance Liver Renal Local Anesthetics Opioids look at pharmacology changes with focus on regional anesthesia and medications used -- Local anesthetics, and narcoticslook at pharmacology changes with focus on regional anesthesia and medications used -- Local anesthetics, and narcotics

6. Approximate CSF Volume

7. ? CSF Volume: Implications Dosage of Drugs tetracaine 1 mg/kg + epinephrine for spinal bupivacaine 0.5-1.0 ml/kg for caudal Duration of action e.g. Spinal Tetracaine with epinephrine larger doses required ?duration of action secondary to CSF volume changes v. increase uptake Bar graph required duration of action, ref Cote chapter, Holzman abstractlarger doses required ?duration of action secondary to CSF volume changes v. increase uptake Bar graph required duration of action, ref Cote chapter, Holzman abstract

8. Total Body Water reaches adult levels by age 1 Ref Besunderreaches adult levels by age 1 Ref Besunder

9. Protein Binding and Clearance Protein binding decreased at birth Albumin and ?-glycoprotein levels decreased Adult levels at 1 year of age Clearance Liver: Phase I & Phase II decreased Renal: GFR 30% of adult Adult levels by 3-5 months of age Phase I: oxidation, reduction, hydrolysis, hydrolation phase II: glucoronidation, sulfation Phase I: oxidation, reduction, hydrolysis, hydrolation phase II: glucoronidation, sulfation

10. General Pharmacology Implications ? CSF Volume ? ? dose & ? duration ? Total Body Water ? ? IV dose, ? ? toxicity ? Protein Binding ? ? %drug available ? ? toxicity ? Clearance ? ? t1/2 ? ? toxicity

11. Local Anesthetics BE CAREFUL with repeated dosing and infusions Neurologic symptoms > cardiac symptoms May not be able to illicit early neurologic symptoms in small children First sign may be a grand mal seizure Case Reports of Toxicity with Infusion 4 children, 1 neonate Children all presented with grand mal seizures Neonate presented with cardiac arrest Toxicity concerned with repeated doses or infusion of local anesthetic: this result of increase dose req�d and shorter duration coupled with longer half life and less protein bound Neuro symptoms: oral tingling, ringing in ears, difficult focusing, shivering, slurred speech, twitching then Grand mal seizures Cardiac: decrease BP secondary to vasodilation and myocardial depressant, decrease in HR as well Toxicity concerned with repeated doses or infusion of local anesthetic: this result of increase dose req�d and shorter duration coupled with longer half life and less protein bound Neuro symptoms: oral tingling, ringing in ears, difficult focusing, shivering, slurred speech, twitching then Grand mal seizures Cardiac: decrease BP secondary to vasodilation and myocardial depressant, decrease in HR as well

12. Opioids Morphine's t1/2 in neonates twice of adults Approaches adult by 2-4 months Implications: BE CAREFUL with opioids and infants Recommendation for opioids For IV, <6 months of age ? consider apnea monitoring For CEI, <12 months of age ? no fentanyl ref lynn/slattery ref lynn/slattery

13. Anatomy

14. Why Regional Anesthesia and Analgesia in Children? Regional Anesthesia only Combined Regional and General Anesthesia  Contraindications

15. Regional Anesthesia Only! Reduce risk of postoperative apnea in former premies Regional anesthesia alone will reduce risk of  postoperative apnea Still need to monitor overnight Techniques Caudal: 0.25% Bupivacaine (1ml/kg) + Clonidine (1 mcg/kg) Spinal: Tetracaine, surgical anesthesia for 60-90 minutes In other age groups, difficult to do regional alone ref Henderson *my recommendationsref Henderson *my recommendations

16. Combined Regional and General Anesthesia Usually regional anesthesia for postoperative analgesia Types Single dose caudal Continuous Epidural/Caudal Infusion Peripheral nerve blocks Field blocks Local infiltration

17. Combined Regional and General Anesthesia: Indications Malignant Hyperthermia Avoid need for opioids Sedation or respiratory depression DSU patients Better analgesia? for CEI Pulmonary disease (cystic fibrosis, rib fractures) Bladder surgery Abdominal &/or thoracic surgery

18. Contraindications to Regional Anesthesia in Pediatrics Parental refusal Need for intact sensory system for postoperative evaluation Sepsis Bleeding disorder Vertebral malformation or previous surgery Allergy

19. Pediatric Regional Anesthesia:Neuroaxial Techniques Caudal anesthesia and analgesia Single dose local anesthetic Morphine Clonidine Continuous infusion Spinal anesthesia

20. Caudal Anesthesia � Technique

21. Caudal Anesthesia

22. Caudal Anesthesia

23. Caudal Anesthesia

24. Caudal AnesthesiaWhere can it go?

25. Caudal in a �

26. Single Dose:Local Anesthetic Volume Traditional 0.05 ml/seg/kg 0.5 ml/kg ? T10 1.0 ml/kg ? T6 For longer duration or lower concentration 1.5 ml/kg ? T2

27. Single Dose:Concentration of Local Anesthetic Balance analgesia with risk of motor block 0.25% Bupivacaine (max 1 mg/kg) Excellent analgesia Risk of some motor block Shorter duration cases Recommend: patients < 18 months of age 0.175% Bupivacaine (max 1.5 mg/kg) Less motor block with good analgesia Higher levels Longer duration Mix 10 ml = 7 ml 0.25% + 3 ml NS

28. Single Dose:Caudal Morphine 30 � 40 mcg/kg Provides analgesia for 12-24 hours No respiratory depression in over 500 children Nausea incidence similar to general anesthesia Less labor intensive Does not require special pain service Side Effects Nausea Itching Propofol therapy single dose Do not need to go to PICU

29. Local with Clonidine Clonidine in adults as oral sedative or adjunct to spinal or epidural Enhances and increases the effect of single shot bupivacaine caudal Risk: sedation with > 1mcg/kg At UTMB, we use for caudal alone for premies and hernia repair

30. Awake Caudals in Neonates

34. Caudal/Epidural Anesthesia and Analgesia: Continuous Infusion Technique and Dose Caudal 16g angiocath with 19g epidural catheter Thread up to thoracic level Guard with clear steridrape Epidural-lumbar Use LOR to saline and continuous pressure method If thread up to thoracic level, need epidurogram Initial Dose: 0.05 ml/seg/kg McClain picuture, flip back to this slide ref bosenbergMcClain picuture, flip back to this slide ref bosenberg

35. Caudal/Epidural Anesthesia and Analgesia: Continuous Infusion Rates and Types Rates <1 yoa: 0.1 to 0.2 ml/kg/hr >1 yoa: 0.1-0.4 ml/kg/hr *less than 0.5 mcg/kg/hr fentanyl to start Types <1 yoa: 0.1% bupivacaine >1 yoa: 0.1% bupivacaine + 3 mcg/ml fentanyl

36. Continuous Caudal/Epidural Infusion: Side Effects and Treatment make table with dose and treatmentmake table with dose and treatment

37. Pediatric Regional Anesthesia: Goals to Understand Identify differences between adults and infants When indicated and contraindicated Techniques Side Effects and Complications

38. Spinal Anesthesia RARELY done Technique IV access 1.5" 22g beveled needle Dose Tetracaine 1 mg/kg and "whiff" (0.02 ml) epinephrine

39. Approximate Distance: Skin to Subarachnoid Space

40. Spinal AnesthesiaPositioning

41. Spinal AnesthesiaCSF Returns

42. Spinal AnesthesiaInjection

43. Spinal Anesthesia Complications No hypotension seen in children under 6 years of age If blood encountered, difficult to identify CSF Limitations Procedure Duration 45 minutes Surgeon Pearls Sugar Nipple Do not flex head Bovie Pad

44. Spinal AnesthesiaBovie Pad Placement