1. PEDIATRIC REGIONAL ANESTHESIA
Jodie L. Johnson, M.D.
Assistant Professor of Clinical Anesthesia
Riley Hospital for Children

2. Introduction
Regional anesthesia being used more frequently in pediatric setting
Most blocks placed at beginning of case
“preemptive analgesia”
Some placed at end
Rarely used as sole anesthetic

3. General Principles
Must acquire experience/dexterity with RA in adults before employing techniques in kids
Be aware of anatomical differences between small child and adult
Be aware of pharmacokinetic differences

4. General Principles Consider individual drug profiles
Skin infection in area of needle/catheter insertion is contraindication
Coagulation disorders are contraindication (unless corrected)
Chemotherapeutic agents cause vascular fragility and thus central blocks are contraindicated in pts on chemo

5. General Principles Have clear strategy
Good organization of equipment, drugs and assistant helps avoid delays
Close monitoring just as important as with GA

6. General Principles
Significant development in regional anesthesia in peds due to:
Advances in safety information
Advances in pharmacology(Ropivicaine)
Improvements in equipment
Types of blocks limited only by skill and interest of individual anesthesiologist

7. Benefits Analgesia provided by block reduces amount of GA
More rapid recovery
Decreased incidence of nausea & vomiting
Faster return of appetite
Earlier discharge
Decreased need for opioids

8. Benefits Regional block eliminates undesirable autonomic reflexes
Laryngospasm decreased
Cardiac dysrhythmias decreased
Muscle relaxation can be obtained with suitable local anesthetic
Can avoid use of muscle relaxants, decrease risk of respiratory insufficiency

9. Benefits
Easier to obtain immobilization of limb after delicate surgery if child is pain-free and there is some residual motor block

10. Benefits Hypotension and urinary retention rarely seen in children
Intra- and post-operative bleeding reduced under neural blockade
A technique of choice if history of MH
Can avoid interference with respiratory tract in premies with BPD

11. Benefits Diminished stress response Fewer episodes of hypoxia
Greater cardiovascular stability
Faster return of GI function
Reduced need for postop vent support
Shorter stay in ICU

12. Safety Low complication rates
Lack of hypotensive response from sympathectomy produced by LA
Loose perineurovascular sheaths
Wider spead of LA from single injection site

13. Pharmacology and Physiology
Increased risk of toxicity with local anesthetics
Infants have immature hepatic metabolism
Increased total body water
Larger Volume of Distribution
Longer elimination half-life
Decreased plasma proteins ( more drug in free/active form)
Rapid increase in blood levels due to higher cardiac output/regional blood flow

14. Pharmacology
Long-acting local anesthetics provide for 6-12 hours of post-operative pain relief
Bupivicaine 0.2% to 0.5%
Ropivicaine 0.2%

15. Pharmacology
Strictly follow maximal dosing guidelines to prevent side effects

16. Physiology
Decreased minimum anesthetic concentration required to block impulse conduction
Nerves have thinner myelin sheaths
Nerves have smaller fiber diameter and a shorter internodal distance
Adequate surgical block with smaller concentrations of LA

17. Equipment
Appropriate equipment decreases risk of injury despite risks of increased toxicity
Use nerve stimulator in anesthetized kids to improve success rate of peripheral nerve blockade
1- or 2-inch insulated needles used

18. Caudal Blockade Most common regional block in children
Simple to perform
Easily adaptable to ambulatory anesthesia practice
Greatly decreases risk of reflex laryngospasm

19. Caudal - Anatomy Sacral hiatus easy to identify
Palpable large bony processes on each side of hiatus called cornua
Hiatus covered by sacrococcygeal membrane
Dural sac may extend to S3 or S4 in infants (short distance between hiatus and dural sac)

21. Caudal- Technique Lateral decubitus position Palpate coccyx
Move finger gently from side to side and proceed in cephalad direction
First double bony protuberance encountered are sacral cornua which define the sacral hiatus

23. Caudal - Technique Sterile prep/drape
21 g butterfly needle usually used
Insert at degree angle with bevel facing anteriorly
Distinct pop felt as sacrococcygeal membrane pierced
Lower angle of needle and advance 2-3 mm

25. Caudal Blockade If outpatient, use just local anesthetic
0.25% Bupiv or 0.2% Ropiv with epi
Test dose: 0.1 ml/kg with 5mcg/ml of epi (max 3ml)
Look for signs of intravascular injection
Increased heart rate > 10 bpm above baseline
Increased blood pressure
>25% change in T-wave amplitude
Doses:
0.5cc/kg for LE/perineal surgery
0.75cc/kg for T-10 level
1cc/kg for lower thoracic level

26. Caudal Blockade
For inpatients, can add PF MSO4 for 18 to 24 hours of postop analgesia
50 mics/kg for perineal surgery
60 mics/kg for mid abdominal incision
70 mics/kg for sternotomy (open hearts)

27. Caudal Blockade Recent interest in Clonidine ? Dose
Less respiratory depression
Less nausea/vomiting
Less pruritis
Similar/prolonged analgesia VS. Morphine
? Dose
1, 2 or 3 mcgs/ kg… to be determined

28. Caudal Blockade ? Use of Clonidine in outpatients
Some staff do not use at all
Some use if > 1 year of age
? Use of hydromorphone
? Use of ketamine

29. Caudal Blockade Major complications rare
Intravascular injection with systemic toxicity
Dural puncture causing high spinal blockade
Infection (especially after interosseous puncture/penetration)

30. Continuous Caudal Catheter
Manufactured kits available
Styletted catheter increases passage to thoracic level
Care taken to prevent fecal contamination

31. Continuous Caudal Catheter
Caudal approach to thoracic epidural anesthesia used in children > 10 years of age
Success related to less densely packed epidural fat
Easy cephalad passage of catheter

32. Continuous Caudal Catheter
Correct placement confirmed by:
Ease of injection
Negative aspiration
Radiographic imaging
Nerve Stimulation through catheter

33. Epidural Block Improved surgical outcomes: Decreased stress response
Fewer episodes of hypoxia
Decreased cardiac morbidity
Decreased pulmonary infections
Decreased thromboembolic events
Decreased blood loss
Faster return of GI function

34. Epidural Block Drugs Used: Ropivacaine/Bupivacaine 2 - Chloroprocaine
Morphine
Clonidine

35. Epidural Block
Line drawn between two iliac crests passes closer to L5 (vs. L3-4 interspace in adults)
Under 1 year of age:
Spinal cord ends at lower level (L3 vs. L1)
Dural sac ends at lower level (S4 vs. S2)

36. Epidural block Lateral decub position Surgical side down
Hips and knees flexed by 90 degrees
Sterile prep/drape
“Loss of Resistance” technique with saline

37. Epidural Block Epidural space more superficial in children than adults
Guideline for determining epidural depth:
1mm/kg of body weight
Depth (cm) = X age (years)
Depth (cm) = X weight (kg)
Use shorter needles and extreme care

38. Epidural Block Dosing: Depends on upper level of analgesia required
> 10 years of age:
Volume to block one spinal segment
V (in ml) = 1/10 X (age in years)
< 10 years old:
0.04ml/kg/segment

39. Epidural Block
Dosing:

40. Epidural Block Complications: Intrathecal injection
High block
Postdural puncture headache
Intravascular injection/Local anesthetic toxicity
Sympathectomy
Hypotension
Bradycardia

41. Epidural Block Complications: Opioid –induced respiratory depression
Damage to neural structures
Infection
Epidural Hematoma  paraplegia
< 1 in 150,000
Usually associated with anticoagulation

42. Epidural Block
Although potential complications, there are multiple benefits
Decreased stress response
Decreased thromboembolic complications
Decreased pulmonary problems
Improved patient/parent satisfaction

43. Ilioinguinal and Iliohypogastric Nerve Block
Simple Block
Good pain relief for hernia repair, hydrocelectomy and orchiopexy
Can be done at beginning of case for both intraop and postop analgesia
May be done intraop under direct visualization

44. Ilioinguinal Nerve Block
Anatomy
Nerves run between abdominal muscles
Close to ASIS
Both blocked by infiltration in area medial to ASIS

45. Ilioinguinal Nerve Block
25-gauge needle
Puncture skin 1 cm medial and 1 cm inferior to ASIS
Three fan-shaped injections
Sub Q wheal as needle withdrawn
Bupiv 0.25% w/ epi up to 2mg/kg used

47. Penile Nerve Block
Provides analgesia after superficial surgery of penis
Circumcision
Meatotomy
Blocks both dorsal nerves at base of penis
Anesthesia to distal two-thirds of penis

48. Penile Nerve Block Usually performed by surgeon Avoid epinephrine
May lead to ischemia of tissue
Complications:
Intravascular injection
Hematoma formation

49. Brachial Plexus Block Can be done at three levels:
Axillary
Interscalene
Supraclavicular
Excellent analgesia during/after surgery on the upper extremities

50. Brachial Plexus Block Axillary approach used most
Major complications rare
Interscalene/ Supraclavicular approaches provide better analgesia of upper arm/shoulder
Higher complication rate : pneumothorax and subarachnoid blockade

51. Brachial Plexus Block
Can perform with one-injection technique using nerve stimulator
Insert needle at 45 degree angle immediately superior to artery high in the axilla
Advance needle toward midclavicle until evidence of nerve stimulation distally

52. Brachial Plexus Block
Can also be performed by feeling distinct “pop” upon entering perineuroplexus sheath
After injection:
Adduct arm
Hold distal pressure on artery

54. Brachial Plexus Block
Transarterial approach not recommended due to possible hematoma formation with secondary nerve compression

55. Parascalene Block Analgesia of shoulder joint
Avoids major structures in neck
Decreases chance of vascular injection
Spares phrenic nerve

56. Parascalene Block Place supine with roll under shoulder
Arm down at side
Head extended and turned to opposite side
Line drawn between midpoint of clavicle and transverse process of C6

57. Parascalene Block
Insert needle perpendicular to skin at junction of upper two thirds and lower one third of drawn line
Nerve stimulator used to determine depth
Usually only 7 –30 mm below skin

58. Parascalene Block Complications: Puncture of external jugular vein
Pneumothorax
Horner’s Syndrome

60. Brachial Plexus Block Dosing:
cc/kg of 0.25% Bupiv or 0.2% Ropiv with 1:200,000 epi

61. Lower Extremity Blocks
Lumbar Plexus (L1-L4)
Sciatic Nerve (L4-S3)
Femoral Nerve

62. Lumbar Plexus Block Provides analgesia to hip, thigh, groin
Lateral decub position
Lines drawn between iliac crests and parallel to spinous processes the through ipsilateral PSIS

63. Lumbar Plexus Block
Insert needle 90 degrees to skin through quadratus lumborum
Nerve stimulation appears as strong contraction of quadriceps muscle

64. Lumbar Plexus Block Complications rare
Epidural spread may occur if needle place too medially

66. Summary Improvements in technique Refinements in equipment
Regional anesthesia safely applied to children