Case 53 - Lower extremity anesthesia

Question 1

What nerves are affected during ACL surgery?

Answer 1

• Femoral Nerve
  
  • skin incision adjacent to patellar tendor
• Tibial Nerve
  
  • tibial periosteum
• Femoral, obturator, sciatic
  
  • internal knee joint capsule
• autograft harvest
  
  • femoral nerve - patellar tendon
  • obturator nerve - gracilis tendon
  • tibial nerve - semitendinosus tendon

Question 2

What are anesthetic options for ACL surgery?

Answer 2

Options

1) general

• side effects of GENA
• inferior post-op pain utilizing opioids

2) general/regional
* femoral nerve block or lumbar plexus block for post-op pain
3) regional

• neuraxial anes: epidural vs spinal
• femoral or lumbar plexus for post-op pain control

Question 3

benefits of femoral nerve catheter

Answer 3

• superior pain control compared to intraarticular, IV opioids, and local infiltration
• minimize opioid use –> decrease opioid side effects
• improved sleep, improved patient satisfaction
• assist with aggresive physical therpay due to controlled pain

Question 4

Which LA would you choose for a femoral nerve block?

Answer 4

Desired block density and duration of post op analgesia dictate choice of local anesthetic:

1) pre-op block for post-op pain control

• bupi 0.5% or ropi 0.75%
• dense block, blunts surgical stimulation, reduces opioid consumption intra-op

2) block done post-op for post-op control

• surgical anesthesia not required, therefore bupi 0.25% or 0.5% ropi
• provides analesia without profound motor blockade

3) continuous catheter
* 0.1% or 0.2% bupi –> provides analgesia, minimizes motor blockade and sensory blockade –> important for PT

Question 5

Fascia iliaca block

Answer 5

• can be used for hip surgery
• inferior to psoas nerve block in terms of analgesia and success of block
• location
  
  • lateral to femoral nerve
  • under fascia iliaca
  • lateral to middle third zone from ASIS to pubic tubercle
  • block relys on spread proximal into lumbar plexus located between psoas major and quadratus lumborm