Local Anesthetics & Regional Anesthesia

  • Local Anesthetics:
    • Mechanism: Block voltage-gated sodium channels, preventing nerve depolarization and transmission of pain signals.
    • Types:
      • Amides: Lidocaine, Bupivacaine, Ropivacaine (metabolized by the liver).
      • Esters: Procaine, Tetracaine, Chloroprocaine (metabolized by plasma cholinesterase).
    • Uses: Local infiltration, nerve blocks, spinal/epidural anesthesia.
    • Special considerations: Toxicity risk with high doses (LAST – Local Anesthetic Systemic Toxicity). Bupivacaine can cause cardiotoxicity.
    • Population/Clinical Use: Used in minor surgical procedures, dental anesthesia, postoperative analgesia.
  • Regional Anesthesia:
    • Mechanism: Uses local anesthetics to block nerve conduction at a specific region, reducing pain and providing anesthesia to a targeted area.
    • Types:
      • Peripheral Nerve Blocks: Brachial plexus (e.g., interscalene, supraclavicular), femoral, sciatic, popliteal, TAP blocks.
      • Neuraxial Anesthesia: Spinal and epidural anesthesia for lower body surgeries, labor analgesia.
    • Uses: Surgical anesthesia, perioperative pain control, multimodal analgesia.
    • Special considerations: Risk of hypotension (spinal/epidural), nerve injury, hematoma formation (avoid in coagulopathic patients).
    • Population/Clinical Use: Ideal for orthopedic, OB-GYN, and vascular surgeries; useful in ERAS (Enhanced Recovery After Surgery) protocols.

📚 References

1️⃣ Miller RD. Miller’s Anesthesia. 9th ed. Philadelphia, PA: Elsevier; 2020.

2️⃣ Morgan GE, Mikhail MS, Murray MJ. Morgan & Mikhail’s Clinical Anesthesiology. 6th ed. New York, NY: McGraw Hill; 2018.

3️⃣ Steiner J. Anesthesia Made Easy: The Survival Guide to Make Your First Anesthesia Rotation a Success. 2nd ed. Independently Published; 2019.