sciatic nerve

Question 1

what block is very helpful for managing phantom limb pain after either below knee or above knee amputations

Answer 1

sciatic block continuous

Question 2

what med and dose is is administered after total knee to manage posterior knee pain

Answer 2

single shot sciatic block using 0.1% ropivicaine

Question 3

very tight as or heart failure what block is sufficient for lower limb procedures

Answer 3

combined femoral and sciatic block

Question 4

when is sciatic nerve block done alone

Answer 4

for ANALGESIA of the lower leg and provides pain relief from ankle fractures or tibial fractures before operative intervention

Question 5

outpatients sciatic blocks and satisfaction

Answer 5

Outpatients undergoing a complex knee surgery that have received combination blocks have decreased pain, hospital admissions, and increased satisfaction

Question 6

sciatic blocks indicated

Answer 6

Mostly indicated for procedures involving the hip, thigh, knee, lower leg & foot

Question 7

Sciatic nerve block in combination with Lumbar Plexus or Femoral block can provide

Answer 7

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

Question 8

Sciatic nerve is the continuation of the

Answer 8

upper division of the sacral plexus

Question 9

sciatic nerve originates from the lumbosacral trunk- composed nerve roots

Answer 9

Originates from the lumbosacral trunk and is composed of nerve roots L4-5 and S1-3

Question 10

the sciatic supples the muscles of..

Answer 10

It supplies the muscles of the posterior thigh, skin of the leg, and muscles of the lower leg and foot

Question 11

blockade of the sciatic nerve occurs where

Answer 11

Blockade of the sciatic nerve may occur anywhere along its course

Question 12

Position: sciatic nerve block

Answer 12

Lateral (side to be blocked in the nondependent position/up)

Bend knee of the affected leg and tilt the pelvis slightly forward (Sims position

Question 13

what is continuous sciatic block used for

Answer 13

continuous sciatic block is very helpful for managing phantom limb pain after either below knee or above knee amputations

Question 14

the keys to making sciatic block work

Answer 14

adequate positioning of the patient and a systematic redirection of the needle until paresthesia is obtained

Question 15

sciatic block posterior/classic approach

Answer 15

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

Question 16

sciatic block injection of LA

Answer 16

25ml

Question 17

sciatic block- needle length

Answer 17

Insert a long (10 cm) insulated needle at a perpendicular angle

Question 18

Sciatic block- what muscle does the needle advance through

what muscles respond to block?

Answer 18

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)

Question 19

side effects of sciatic nerve blocks

Answer 19

Mild hypotension due to sympathetic fibers being blocked
Residual dysesthesias (abnormal sensation) usually improving 1-3 days

Question 20

major risk of popliteal nerve block

Answer 20

Major risk:

Vascular puncture

Question 21

what type of blocks are excellent for coverage for foot and ankle surgery (spares most of hamstring muscles, allowing amulation

Answer 21

popliteal nerve block

Question 22

for posterior popliteal approach - place probe

Answer 22

May use US … place probe just above the crease of fossa

Question 23

this block spares hamstring and allows ambulation

Answer 23

popliteal

Question 24

popliteal block positioning

Answer 24

Prone position and flex the leg (knee) to aid in identifying the margins of the popliteal fossa (prop the ankle on pillows/towels/blankets)

Question 25

where do you find the epicondyles of the femur

Answer 25

The base of both triangles forms a line between the medial and lateral epicondyles of the femur.

Question 26

how the fossa itself divided for popliteal approach

Answer 26

into equal medial and lateral triangles

Question 27

for popliteal posterior approach the needle

Answer 27

needle insertion at 5-6cm proximal to the skin crease and 1 cm lateral to the midline of the triangle

Question 28

popliteal needle
degree
gauge
direction

Answer 28

5-10cm insulated
22g
45-60degree
anterosuperior direction

Question 29

how much local is injected into popliteal block

Answer 29

30-40ml

Question 30

popliteal is advanced to what depth 1.5-2cmuntil

Answer 30

foot twitch

Question 31

Most medial branch of the femoral nerve

Answer 31

saphenous nerve at knee

Question 32

Saphenous Nerve – what does it innervate

Answer 32

Innervates skin over the medial leg & ankle joint

Question 33

saphenous nerve is commonly used in conjunction with with block

Answer 33

Commonly used in conjunction with sciatic (popliteal) block to provide anesthesia/analgesia below the knee

Question 34

how much local anesthetic is injected into the saphenous nerve

Answer 34

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

Question 35

saphenous nerve- needle length and direction

Answer 35

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

Question 36

indications for ankle block

Answer 36

diagnostic, therapeutic or surgical procedure on the foot

Question 37

ankle block can be good for

Answer 37

postoperative analgesia

Question 38

what is advantageous of the ankle blok

Answer 38

it is fast and low risk

Question 39

what two things do we avoid with ankle block

Answer 39

excessive la volume

avoid epi

Question 40

ankle block
Blockade of all the nerves serving the foot at the level of the proximal ankle joint
Requires 5 separate injections

Answer 40

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

Question 41

sural nerve injection amount

Answer 41

5ml