1. Bernie Miller, MD, CA3 OHSU APOM
Regional Anesthesia
Bernie Miller, MD, CA3
OHSU APOM

2. Regional Anesthesia
Rendering a specific area of the body insensate to stimulus of surgery or other instrumentation

4. Advantages Major Intra-abdominal surgery Ambulatory Surgery
Cardiac disease
Vascular surgery
Pulmonary resection/rib fractures
Obstetric Patients
Chronic Pain
Oncologic Surgery?

5. Types of Regional Anesthesia
Topical
Local/Field
IV block- “Bier Block”
Peripheral Nerve block (named after the nerve)
Plexus block (eg lumbar, brachial)
Central Neuraxial (spinal, epidural)

6. Topical Anesthesia Application of local anesthetic to mucous membrane
Uses
Awake oral or nasal intubation
Superficial surgical procedure
Advantage
Easy to do
Disadvantage
Potential for large doses leading to toxicity

7. Airway blocks Injection of LA to block airway nerves
Uses: facilitation of awake intubation
Advantage: complete lack of sensation in the airway, blunting of airway reflexes
Disadvantage:
Potential for injury/injection of surrounding major vascular structures or CSF
More invasive than topicalization

9. Glossopharyngeal Nerve Block

10. Superior Laryngeal Block
(sensory branch)

11. (recurrent laryngeal)
Transtracheal block
(recurrent laryngeal)

12. Local/Field Anesthesia
Application of local subcutaneously to anesthetize distal nerve endings (small local area or field)
Uses:
Suturing, minor superficial surgery, line placement
Advantages:
minimal equipment, technically easy, rapid onset
Disadvantages:
potential for toxicity if large field

13. “IV” Block – “Bier” Block
Injection of local anesthetic IV for anesthesia of an extremity
Uses
Any short surgical procedure on a distal extremity
Advantages
Technically simple, minimal equipment, rapid
Disadvantages
Duration limited by tolerance of tourniquet pain, toxicity

15. Peripheral/Plexus Nerve Block
Injecting local anesthetic near the course of a named nerve or plexus
Uses:
Surgical procedures in the distribution of the blocked nerve
Pain control of a specific area
Advantages:
More bang for your buck (more coverage with less LA)
Less narcotic
Patient can either be sedated or fully awake and functional
Limb specific
Disadvantages:
technical complexity, neuropathy

16. Single shot vs Catheter
Fast placement
Smaller introducing needle
More complex placement- two step process
Duration of anesthetic not limited to duration of drug action

17. Setup/method
Often in a designated “block” room or space with dedicated team
Supplies
Monitor vitals
Sedation
Can use ultrasound guidance or nerve stimulation
Positioning!
Localize nerve based on anatomy, confirm location with device
Communicate with patient
Inject and/or or thread catheter
Test dose

18. Nerve stimulator
Provides short, low frequency electric impulse to elicit defined muscle response
Based on known innervation of nerve
Can use transcutaneously to plan approach
Can use with needle during block
Good response at low output indicates close proximity to the nerve
Inject local
Should lose response as conduction blocked

19. Ultrasound vs StimulatorUS
Stimulator
Benefit
Direct visualization
Real-time visualization
Hard-to-find landmarks
Drawback
Osseous or gas-filled structures impede signal
Takes up an extra hand
Can be misleading (need to see tip)
Benefit
Confirm correct nerve function
Attaches to needle in use
Drawback
No visualization of neighboring structures
Requires assistant’s hands
Discomfort
Unreliable in neuropathy

20. Peripheral/Plexus Block
Upper Extremity
Brachial plexus
interscalene
supraclavicular
Infraclavicular
Axillary
Median
Ulnar
Radial
Lower Extremity
Femoral
Sciatic
Obturator
Saphenous
Tibial
Ankle
Lumbar plexus
Others: TAP block, paravertebral block

21. Upper Extremity Plexi Cervical Plexus Brachial Plexus
Ventral Rami of C1-C4
Located deep to the SCM in the neck
Advanced regional technique
Brachial Plexus
Ventral rami of C5-T1
Responsible for cutaneous and muscular innervation of upper limb

22. Brachial plexus blocks
Level
Potential
Drawback
Uses
Interscalene
Roots, Trunks
Spares inferior trunk
Shoulder, upper arm
Supraclavicular
Trunks, Divisions
Risk for pneumo
Entire arm, including hand
Infraclavicular
Cords
Pectoral discomfort
Entire arm, good for catheter

23. Interscalene Block Patient position Anatomical landmarks
Supine with head rotated 30 degrees to C/L side
Anatomical landmarks
Determine interscalene groove (AS & MS) at the level of C6 where the nerves emerge from behind the scalene muscles (be careful of the EJ!).
Do not confuse the interscalene groove with the AS/SCM groove.

25. Casualty nerves: phrenic – hemidiaphragmatic paralysis
sympathetic chain – Horner’s
recurrent laryngeal - hoarseness

27. Supraclavicular

28. Infraclavicular

29. Axillary Nerve Block Advantages
Provides anesthesia for forearm & wrist
Fewer complications than a supraclavicular block
Limitations
Not for shoulder or upper arm surgery
Musculocutaneous nerve lies outside of the sheath and must be blocked separately
Complications
Intravascular injection
Elevated bleeding time increases risk for hematoma

30. Axillary Block Position Head turned away from arm being blocked
Abduct to 90º
Forearm is flexed to 90º
Palpate brachial artery for pulse

31. Axillary Nerve Block

32. Axillary Nerve Block

33. Femoral Nerve Block (L2-L4)
Uses:
Knee arthroscopy in combination with intra- articular local anesthetic
Good for femoral shaft fractures, ACL, TKA with multimodal regimen
Limitations:
Not reliable for posterior knee, lower leg or upper thigh
Complications:
Arterial puncture
Abdominal cavity puncture

34. Femoral block landmarks “NAVL”
Draw a line between the ASIS and the pubic tubercle
Determine location of femoral artery
Introduce needle one cm lateral to artery

36. Sciatic Nerve Block (L4-5, S1-3)
Uses:
Nearly complete blockade of the foot and ankle
What does the sciatic nerve turn into?
Limitations:
Not a good block for upper thigh or hip
Advantages:
Easy to palpate anatomic landmarks
No major vessels near the nerve

39. Popliteal nerve block Uses : Lower 2/3 of leg
Does not cover medial (saphenous)
Objective
Find the sciatic bifurcation
Anesthetize both branches
Tibial
Common peroneal

40. Posterior Approach

41. Finding the bifurcation
Proximal
Distal

42. Ankle Block Five nerves Tibial Superficial peroneal Saphenous Sural
Deep peroneal

43. Ankle block

44. Lower Plexus Blocks Lumbar Plexus L2-L4
Form the obturator, lateral femoral cutaneous, and femoral nerves
Provides sensory and motor innervation to anterior lower extremity
Lumbosacral plexus L4-L5, S1-S3
Primarily forms the sciatic nerve
Provides motor and sensory innervation to posterior lower extremity
Rarely done

45. L2-L4

46. Lumbar Plexus block Uses: Disadvantages Potential complications
Obturator, femoral, and lateral femoral cutaneous nerves in the belly of the psoas muscle
Knee, thigh and hip
Catheter frequently used to extend block
Disadvantages
Not useful for lower leg or foot
Cannot use real-time ultrasound
Potential complications
Bleeding from psoas muscle bed
Increased systemic absorption of local anesthetic from increased vascularity

47. Lumbar plexus Positioning
Lateral decubitus positioning with the blocked side up
Foot of the side being blocked should be over the dependent leg so the twitches of the patella can be seen.

48. Lumbar plexus Landmarks
Locate both iliac crests and and draw a line between them, this is usually the location of L4 (Tuffier’s)
Generally, the plexus will be 4cm lateral to the spinous process along this line.

49. TAP block Transversus abdominis plane block
Good for abdominal surgery
Single shot (less frequently catheter)
Can be used as rescue
LA spread between internal oblique and transversus abdominus muscles
Anesthetize anterior rami of T7-L1

50. TAP block

51. Paravertebral block
Anesthetize thoracic spinal nerves within paravertebral space above L1
Thoracic, chest wall, breast, rib fx
Unilateral or bilateral
Usually single shot, catheter possible
Landmark or ultrasound
Complications?

53. In-line approach

54. Neuraxial anesthesia

55. Epidural
Injection of local anesthetic +/- adjunct into the epidural space (lumbar, thoracic, caudal)
Usually catheter is left in place for continued infusion
Useful for intraoperative and post-operative pain control as well as labor analgesia
Benefits: decreased ileus, pain control without respiratory depression, improved perfusion
Potential drawbacks: hypotension (sympathectomy), pruritis, possible wet tap, potential for epidural hematoma or vascular injection, one-sided or patchy block

56. Thoracic epidural catheter

57. Spinal Injection of local anesthetic +/- adjunct into spinal space
Usually single shot procedure
Can combine with epidural (CSE)
Lumbar ONLY
Complete motor and sensory block
Fast to perform, quick onset, relatively short duration depending on choice of anesthetic, rarely fails
More pronounced hypotension, possible spinal HA, possible high spinal

58. Spinal via introducer

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