what block is very helpful for managing phantom limb pain after either below knee or above knee amputations
sciatic block continuous
what med and dose is is administered after total knee to manage posterior knee pain
single shot sciatic block using 0.1% ropivicaine
very tight as or heart failure what block is sufficient for lower limb procedures
combined femoral and sciatic block
when is sciatic nerve block done alone
for ANALGESIA of the lower leg and provides pain relief from ankle fractures or tibial fractures before operative intervention
outpatients sciatic blocks and satisfaction
Outpatients undergoing a complex knee surgery that have received combination blocks have decreased pain, hospital admissions, and increased satisfaction
sciatic blocks indicated
Mostly indicated for procedures involving the hip, thigh, knee, lower leg & foot
Sciatic nerve block in combination with Lumbar Plexus or Femoral block can provide
Sciatic nerve block in combination with Lumbar Plexus or Femoral block (3-in-1) can provide complete anesthesia and postoperative analgesia for lower extremity surgery
Sciatic nerve is the continuation of the
upper division of the sacral plexus
sciatic nerve originates from the lumbosacral trunk- composed nerve roots
Originates from the lumbosacral trunk and is composed of nerve roots L4-5 and S1-3
the sciatic supples the muscles of..
It supplies the muscles of the posterior thigh, skin of the leg, and muscles of the lower leg and foot
blockade of the sciatic nerve occurs where
Blockade of the sciatic nerve may occur anywhere along its course
Position: sciatic nerve block
Lateral (side to be blocked in the nondependent position/up)
Bend knee of the affected leg and tilt the pelvis slightly forward (Sims position
what is continuous sciatic block used for
continuous sciatic block is very helpful for managing phantom limb pain after either below knee or above knee amputations
the keys to making sciatic block work
adequate positioning of the patient and a systematic redirection of the needle until paresthesia is obtained
sciatic block posterior/classic approach
Identify the greater trochanter, posterior iliac spine & sacral hiatus
1st-draw a line from the posterior superior iliac spine (PSIS) to the greater trochanter
2nd-draw a line from the sacral hiatus to the greater trochanter
3rd-at the midpoint of line one draw a line that is perpendicular and intersects line two
Needle insertions is at the intersection of line 2 and 3
sciatic block injection of LA
25ml
sciatic block- needle length
Insert a long (10 cm) insulated needle at a perpendicular angle
Sciatic block- what muscle does the needle advance through
what muscles respond to block?
Advance the needle through the gluteal muscles (a motor response of these muscles and leg may be elicited) until plantar or dorsiflexion is elicited (plantar flexion- distal ankle, foot or toes… or foot inversion)
side effects of sciatic nerve blocks
Mild hypotension due to sympathetic fibers being blocked Residual dysesthesias (abnormal sensation) usually improving 1-3 days
major risk of popliteal nerve block
Major risk:
Vascular puncture
what type of blocks are excellent for coverage for foot and ankle surgery (spares most of hamstring muscles, allowing amulation
popliteal nerve block
for posterior popliteal approach - place probe
May use US … place probe just above the crease of fossa
this block spares hamstring and allows ambulation
popliteal
popliteal block positioning
Prone position and flex the leg (knee) to aid in identifying the margins of the popliteal fossa (prop the ankle on pillows/towels/blankets)
where do you find the epicondyles of the femur
The base of both triangles forms a line between the medial and lateral epicondyles of the femur.
how the fossa itself divided for popliteal approach
into equal medial and lateral triangles
for popliteal posterior approach the needle
needle insertion at 5-6cm proximal to the skin crease and 1 cm lateral to the midline of the triangle
popliteal needle
degree
gauge
direction
5-10cm insulated
22g
45-60degree
anterosuperior direction
how much local is injected into popliteal block
30-40ml
popliteal is advanced to what depth 1.5-2cmuntil
foot twitch
Most medial branch of the femoral nerve
saphenous nerve at knee
Saphenous Nerve – what does it innervate
Innervates skin over the medial leg & ankle joint
saphenous nerve is commonly used in conjunction with with block
Commonly used in conjunction with sciatic (popliteal) block to provide anesthesia/analgesia below the knee
how much local anesthetic is injected into the saphenous nerve
The saphenous nerve may be blocked by injecting 5-10 ml of local anesthetic in a subcutaneous ring from the medial aspect of the tibia to the border of the patellar tendon
saphenous nerve- needle length and direction
Insert a short block needle 2 cm distal to the tibial tuberosity and directed medially (infiltrating 5-10 mL of LA) toward the posterior aspect of the leg
indications for ankle block
diagnostic, therapeutic or surgical procedure on the foot
ankle block can be good for
postoperative analgesia
what is advantageous of the ankle blok
it is fast and low risk
what two things do we avoid with ankle block
excessive la volume
avoid epi
ankle block
Blockade of all the nerves serving the foot at the level of the proximal ankle joint
Requires 5 separate injections
Posterior tibial nerve- direct continuation of tibial
Deep peroneal nerve- runs off common peroneal
Superficial peroneal nerve- runs off common peroneal
Sural nerve- branch of tibial
Saphenous nerve (terminal branch of femoral)- not a part of sciatic system
sural nerve injection amount
5ml