Download Femoral nerve block mgmc

Femoral nerve block
Dr. S. Parthasarathy
MD., DA., DNB, MD (Acu), Dip. Diab.
DCA, Dip. Software statistics
PhD (physio)
Mahatma Gandhi Medical college and
research institute , puducherry India
Indications
 procedures carried out on the anterior
thigh
 Combined with other blocks – lower leg
and foot surgeries
 femoral fracture analgesia
 With catheter technique – post op
analgesia of knee
Anatomy
• largest nerve of the lumbar plexus ( L2- L4)
• supplies the muscles and the skin of the
anterior compartment of the thigh
• passes downwards in the groove between
psoas and iliacus
• enters the thigh beneath the inguinal ligament
• nerve lies on iliacus, a finger’s breadth lateral
to the femoral artery
Anatomy
Technique
• A line is drawn connecting the anterior
superior iliac spine and the pubic tubercle.
• The femoral artery is palpated on this line, and
a 22-gauge, 4-cm needle is inserted 0.5 to 1 cm
both below the inguinal ligament and lateral to
the femoral artery.
• The initial insertion should abut the femoral
artery in a perpendicular fashion.
• wall” of local anaesthetic is developed by
redirecting the needle in a fanlike manner
Line marked
Needle insertion
Injection of LA spanning out
Drugs
• 20 mL of local anaesthetic
0.25 to 0.5 % bupivacaine
• 0.25% bupivacaine or 0.2% ropivacaine for
catheter techniques
• 8- 10 ml / hour is enough
Nerve stimulator
• The femoral artery should be palpated and marked.
The site of introduction of the needle is vertically, 0.5
to 1 cm both below the inguinal ligament and lateral
to the femoral artery.
• Set the nerve stimulator at a frequency of 2 Hz and a
current of 2.5 mA.
• Go anteroposterior and get motor response of the
femoral nerve (contraction of the quadriceps muscle
with the phenomenon of the “dancing patella”).
• Reduce to 1 Hz and 0.5 mA - same response - and
inject.
technique
• Needle positioned,
• 20 mL of preservative-free NS injected
appropriate-size catheter is inserted
approximately 10 cm past the needle tip.
• Once the catheter has been secured with a
plastic occlusive dressing, the initial bolus
injection of drug is carried out and the
infusion is started.
Continuous catheter
USG probe
USG guided femoral nerve block
Tips
• The femoral artery and femoral nerve are not
in the same anatomic compartment.
• Therefore, if solution spreads perivascularly,
the needle should be repositioned to produce
local anesthetic spread below the fascia iliaca.
Anatomy
• The obturator nerve emerges from the medial
border of the psoas muscle at the pelvic brim
and travels along the lateral aspect of the
pelvis anterior to the obturator internus
muscle and posterior to the iliac vessels and
ureter. It enters the obturator canal cephalad
and anterior to the obturator vessels, which
are branches from the internal iliac vessels.
Obturator nerve block
adductor muscles, hip and knee
joint
• In the obturator canal, the obturator nerve
divides into anterior and posterior branches
The anterior branch supplies the anterior
adductor muscles ,articular branch to the hip
joint , cutaneous area on the medial aspect of
the thigh.
• The posterior branch innervates the deep
adductor muscles and sends an articular
branch to the knee joint..
Technique
• The pubic tubercle should be located and an “X”
marked 1.5 cm caudad and 1.5 cm lateral to the
tubercle
• The needle is inserted at this point, and at a depth of
approximately 2 to 4 cm it contacts the horizontal
ramus of the pubis.
• The needle is then withdrawn, redirected laterally in
a horizontal plane, and inserted 2 to 3 cm deeper
than the depth of the initial contact with bone.
• The needle tip now lies within the obturator canal
• With the needle in this position, 10 to 15 mL of local
anesthetic solution is injected
Technique
Complications
• The obturator canal is a vascular location;
thus, the potential exists for intravascular
injection or hematoma formation,
• more theoretical than clinical concerns.
• Volume determines success.
Probe position
USG
Lateral femoral cutaneous N block
why ?
Technique
Technique
• The anterior superior iliac spine is marked in
the supine patient,
• and a 22-gauge, 4-cm needle is inserted at a
site 2 cm medial and 2 cm caudal to the mark,
the needle is advanced until a “pop” is felt as
the needle passes through the fascia lata.
Local anesthetic is then injected in a fanlike
manner above and below the fascia lata, from
medial to lateral.
Technique
Three in one block
• The perivascular approach to the psoas
compartment is based on the premise that
injection of a large volume of local anesthetic
within the femoral canal while maintaining
distal pressure will result in proximal spread
of the solution into the psoas compartment
and consequent lumbar plexus block
Technique
• The femoral artery is marked.
A 22- gauge, 5- cm needle is advanced lateral
to the artery in a cephalad direction
Paraesthesia – 30 ml given
Distal pressure applied
Success - ?
Thank you all