Transcript Slides 17 Femoral Nerve Blocks and 3-in

Soli Deo Gloria
FEMORAL NERVE BLOCKS
AND
3-IN-1 NERVE BLOCKS
Developing Countries Regional Anesthesia Lecture Series
Lecture 17
Daniel D. Moos CRNA, Ed.D.
U.S.A.
[email protected]
Disclaimer
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Every effort was made to ensure that material and
information contained in this presentation are
correct and up-to-date. The author can not accept
liability/responsibility from errors that may occur
from the use of this information. It is up to each
clinician to ensure that they provide safe anesthetic
care to their patients.
Introduction
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Currently underutilized for clinical anesthesia and
postoperative pain management.
Lower extremity peripheral nerve blocks have
historically been performed less frequently than
peripheral nerve blocks of the upper extremities.
3-in-1 Block
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Suppose to block the femoral nerve, lateral femoral
cutaneous nerve, and obturator.
Indications for FNB/3-in-1 Block
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Operations of anterior thigh (lacerations, skin
grafts, muscle biopsy)
Pin or plate insertion at the upper femur
Femur fractures
Analgesia of hip (dislocations, femoral nerve
fractures)
Analgesia of the knee
Limitations- Knee
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Not complete analgesia of the knee. The knee is
innervated by the femoral, obturator, and sciatic
nerve.
These blocks will create a motor block of the
quadriceps.
Limitations- Hip
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Hip is innervated by the femoral, obturator, and
lateral femoral cutaneous nerve.
A small contribution comes from the sciatic but
should not be significant.
Anatomy
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The femoral nerve is the largest branch of the
lumbar plexus.
Femoral nerve is created from contributions from L2,
L3, and L4.
The femoral nerve enters into the thigh under the
inguinal ligament, between the psoas and iliacus
mucle.
Femoral Triangle
Anatomy
Skin
Femoral
Artery
Fascia lata
Femoral Vein
Femoral Nerve
Fascia iliaca
Iliopsoas
muscle
Pectineous
muscle
Anatomy
Femoral Nerve “sheath”
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Contains the femoral nerve and artery
It is located between the psoas and iliacus muscle.
It is located below the fascia iliaca.
Lateral Femoral Cutaneous Nerve and
Obturator Nerves
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Lateral femoral cutaneous nerve is formed by
contributions from L2 and L3
Obturator nerve is formed by contributions from L2,
L3, and L4
Innervations
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Femoral Nerve: anterior and medial portion of the
thigh (sartorious, pectineus, quadriceps); cutaneous
portion of medial and lateral thigh; periosteum of the
femur. The posterior division of the femoral nerve will
become the saphenous nerve.
LFCN: purely sensory to lateral buttock, thigh, and
knee joint.
Obturator Nerve: sensory to medial thigh, hip joint,
and adductor muscles.
Anatomy
Contraindications
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Burn or infection at the injection site
Coagulopathy
Vascular graft
Neurological disease (relative)
Patient refusal
Local anesthetic allergy
Technique
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Same for either block
Locate the anterior superior iliac spine and the
pubic tubercle. A line between these two structures
is where the inguinal ligament is located.
Just below this line is the femoral nerve.
Technique
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Palpate the femoral artery
The femoral nerve should be located 1 cm lateral to
the palpation.
Medial to lateral the structures are femoral vein,
artery, and nerve.
Technique
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For paresthesia technique a blunted needle should be
used.
Insert perpendicular while aspirating for blood
Once paresthesia is elicited pull back slightly and
inject. There should be no pain.
If you are at a depth of 4-5 cm pull back and start
over.
As with any peripheral nerve block frequent
aspiration is mandatory.
Technique 2 pop technique
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Blunted needle
A slight increase in resistance followed by a loss of
resistance indicates that you have transversed the
fascia lata.
A second increase in resistance followed by a loss
of resistance indicates that you have transversed
fascia iliaca.
Deposit local anesthetic. (aspirate, make sure no
pain, etc.)
Technique Nerve Stimulator
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2 inch, 22 gauge needle (insulated)
2 cm lateral to femoral pulse, 2 cm down from
inguinal ligament.
Identify quadriceps contraction
Reduce stimulation to 0.5 mA and adjust needle for
continued quad contraction.
Injection of 1 ml of local anesthetic should see the
contractions start to fade.
Local Anesthetics
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FNB = 15-20 ml of local
3-in-1 NB = 25-30 ml of local
Use 1:200,000 epi containing solutions or add
yourself.
1-2% lidocaine will have an onset of 10-20 minutes
and last 2-5 hours for anesthesia; up to 8 hours for
analgesia.
Bupivacaine will have an onset of 15-30 minutes and
last up to 5-15 hours for anesthesia and up to 30
hours for analgesia
Complications
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Intravascular injection
Local anesthetic toxicity
Nerve trauma
Prolonged motor blockade of the muscles of the
thigh
Hematoma formation
Block failure
Differences between FNB and 3-in-1 Nerve
Block
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Volume: 20 ml or less for FNB; 25-30 ml of 3-in-1
Nerve Block
More volume = more spread
Pressure applied distally to the injection site will
help the spread of local anesthetic further up to the
lateral femoral cutaneous nerve and LFCN.
Controversy
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Studies have found that the 3-in-1 nerve block
inconsistently blocks the obturator nerve (4%-78%)
depending on volume (up to 40 ml).
Most likely the 3-in-1 nerve block will consistently
block the FN and LFCN
Controversy “Is there really a sheath”
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Cadaver studies have found no conclusive evidence
that there is a femoral sheath.
References
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Burkard J, Lee Olson R., Vacchiano CA. Regional Anesthesia. In Nurse Anesthesia 3rd edition.
Nagelhout, JJ & Zaglaniczny KL ed. Pages 977-1030.
Morgan, G.E. & Mikhail, M. (2006). Peripheral nerve blocks. In G.E. Morgan et al Clinical
Anesthesiology, 4th edition. New York: Lange Medical Books.
Moos, D.D. & Cuddeford, J.D. (1998). AANA Journal Course for nurse anesthetists- Femoral
nerve block and 3-in-1 nerve block in anesthesia. AANA Journal volume 66; issue 4.
Wedel, D.J. & Horlocker, T.T. Nerve blocks. In Miller’s Anesthesia 6th edtion. Miller, RD ed.
Pages 1685-1715. Elsevier, Philadelphia, Penn. 2005.
Wedel, D.J. & Horlocker, T.T. (2008). Peripheral nerve blocks. In D.E. Longnecker et al (eds)
Anesthesiology. New York: McGraw-Hill Medical.