Stoelting, RK and Miller, RD. Basics of Anesthesia, 3rd Edition. Chapters 12, 13.
Outline below.
Understand the techniques, risks, indications, and contraindications for spinal blocks, epidural blocks, and peripheral nerve blocks
1. What are the advantages of neuraxial anesthesia over general anesthesia? Disadvantages?
2. Describe preoperative preparation for regional anesthesia. Compare with general anesthesia.
3. Describe relevant anatomy for spinal and epidural blocks.
4. What are contraindications to neuraxial blocks? To peripheral nerve blocks?
5. Describe the techniques for spinal and epidural anesthesia.
6. At what vertebral level should epidural catheters be placed?
7. What determines level and duration of block for spinals? For epidurals?
8. What are the complications of neuraxial anesthesia?
9. How can incidence of post-dural puncture headaches be reduced?
10. List the peripheral nerve blocks (PNB’s) most commonly used for upper and lower extremity surgery, and examples of their use.
11. What are the risks of PNB’s?
12. What are the advantages of PNB’s over neuraxial anesthesia? Disadvantages?
· Avoid GA complications (trauma to lips, teeth, pharynx, vocal cords; bronchospasm; aspiration; prolonged somnolence; prolonged paralysis from atypical response to NMB; malignant hyperthermia)
· Less anesthetic required
· faster wake-up?
· quicker recovery?
· Faster ambulation, faster discharge (peripheral nerve blocks)
· N/V less common
· post-op pain minimized
· attenuated stress response (SAB, epidural)
· decreased blood loss (SAB in hip/prostate surgery)
· decreased thromboembolic complications (hip surgery, SAB)
· improved graft patency? (LE bypass graft surgery)
· Time: takes longer to initiate than GA, but may save time post-op
· Equipment: extra equipment necessary – inconvenient, ?costly (savings in recovery room & GA costs may make up for equipment costs)
· Personnel: extra person may be needed to assist in block placement. However, can usually use nursing already present (HA, PACU, or OR nurses)
· GA still possible
· Additional skill required
· Regional techniques. Hadzic et. al., “The Practice of Peripheral Nerve Blocks in the United States: A National Survey.” Regional Anesthesia and Pain Medicine 23(3): 241-246, 1998. 48.9% respondents felt their training in peripheral nerve blocks was inadequate
· Management of awake or LIGHTLY sedated patients
· Monitoring requirements
· Emergency equipment and drugs should be readily available
· POSITIONING
· SEDATION (preoperative, intraoperative): should be able to communicate with patient
·
Patient selection
may avoid RA if…
·
anatomy: difficult
(e.g., morbid obesity, kyphoscoliosis)
·
personality:
extreme anxiety, drug addition
·
patient should
understand what to expect (block placement, side effects, complications,
alternatives)
·
PDPH
·
Caused by leakage
of CSF
·
Small gauge and
pencil point needles decrease risk
·
Epidural blood
patch treats most cases
·
Pruritus
·
Hypotension
·
Urinary retention
·
Prolonged PACU stay
(agent, surgery dependent)
·
TNS (TRI) - Spinal
·
Neurologic injury
·
Epidural hematoma
·
Epidural abscess,
meningitis
·
Failed block
·
Systemic toxicity
(epidural)
·
technically easier
·
less time to
perform
·
faster onset
·
higher success rate
·
better block of
sacral dermatomes
·
less likely to have
systemic local anesthetic toxicity and post-op back pain
·
PDPH less likely
·
less hypotension
(if epinephrine not added)
· post-op pain relief
· may take longer to perform
· failed epidural may be less likely
· rapid onset, and still have epidural for POP
· SAB useful in cases where
· duration of surgery predictable
· there is minimal need for prolonged post-operative pain control, or other means of control work well
· possible cases of difficult airway
· e.g., THR, TKR, TURP, C-section, BTL
· Epidural used in cases
· Surgery of variable duration
· Post-operative pain prolonged or difficult to control with other methods
· Difficult airways
· E.g., labor epidural, LE bypass procedures, upper abdominal or thoracic surgeries
Blockade of individual nerves or nerve roots, or groups of these isolated to a particular area.
Less hemodynamic change
Longer pain relief vs. SAB (can also place catheters if necessary)
No delay in discharge from PACU
Time: takes longer to perform and establish block
Greater risk of systemic local anesthetic toxicity (vs. SAB)
Technically more difficult
Brachial plexus blocks
Intravenous Regional Anesthesia (IVRA)
Paravertebral nerve blocks (PVB)
Lumbar plexus block
Sciatic nerve block
Ankle block