Week 4 Regional Peripheral Blocks Flashcards
head and neck, lower, upper
complications of Head and neck blocks:
IV injection Subarachnoid or epidural placement of LA Nerve injury Bleeding Infection
Absolute Contraindications (of any nerve block):
- Patient refusal
- Uncorrected coagulation deficiencies
- Infection at the site of the block
- Systemic anticoagulation
Relative Contraindications (of any nerve block):
- Arbitrary values for platelet counts of less than 100,000
- Prothrombin time (PT), activated partial thromboplastin time (aPTT), and bleeding times that are elevated
- Severe bleeding with or without symptomatic hypovolemia or the potential for severe bleeding
- Patient age
- Uncooperative and/or Confused patients
- Chronic neurological disorders
- Local anesthetic allergy
- Caution with patients that have history of Mobitz I, II, or third degree heart block ***
- Peripheral neuropathy
Cervical Plexus
insert image
cervical plexus blocks can be used in various surgical procedures including
- neck and shoulders,
- Para/thyroid operations, and
- carotid endarterectomies
Cervical plexus is formed from the ;
the anterior rami of C1-C4
Cervical plexus supplies sensation to the:
Supplies sensation to the
- jaw,
- neck,
- occiput,
- chest and
- shoulder
Lumbar plexus supplies _______ innervation to:
motor AND Sensory innervation to anterior portion
-and cutaneous sensory medial lower leg
The largest nerve trunk in the body?
Sciatic
Sciatic nerve is derived from :
anterior rami of L4-S3
Name the 4 major nerves that supply all of the lower extremity:
- Lateral cutaneous nerve (common peroneal)
- Femoral nerve (anterior crural nerve)
- Obturator nerve
- Sciatic nerve
Lumbar Plexus Block does not supply complete anesthesia of LE because it cannot achieve blockade of:
- the sacral roots that supply the sciatic nerve
- need to do a different blocks for complete block of LE
This block has the HIGHEST complication raters of any peripheral nerve block:
Posterior Lumbar Plexus (PSOAS COMPARTMENT) block
-it is relatively close to multiple sensitive structures
Needle size and gauge needed to perform a Posterior lumbar plexus (psoas) compartment block:
- 8-15cm insulated
- 21 g
When performing a Posterior lumbar plexus (psoas) compartment block what femoral motor response is elicited? What is the mV requirement?
- Quadriceps
- < or = 0.5 mA
When performing a Posterior lumbar plexus (psoas) compartment block how much volume of LA is administered?
20-30mL of LA
LA volumes greater than 20mL may increase the risk of: (2)
- bilateral spread and
2. contralateral limb involvement
Name the nerves involved in a femoral 3 in 1 block:
- femoral
- lateral femoral cutaneous
- obtruator nerves
Considerations for femoral nerve block: (3)
- local infection
- hx of vascular grafting
- local adenopathy (large lymph nodes)
Needle size and gauge to perform a femoral block:
short 5 cm insulated needle
22G
volume of LA injected when performing a femoral block:
30-40 mL of LA
a femoral 3 in 1 block by most is regarded as :
femoral nerve block only
indications for femoral block:
- post op pain relief of knee surgeries (hip and ankle)
- surgical indications: soft tissue exploration, biopsy, repair of lac of the anterior thigh
blocking the SAPHENOUS vein occurs in what block?
femoral NB
Lateral Femoral cutaneous nerve block is (type of block)
What area?
- purely sensory nerve
- to lateral aspect of the thigh
Complications with lateral femoral cutaneous nerve blocks are:
rare
complications are rare
lateral fem. cutaneous NB’s are used in the dx and tx of:
meralgia parasthetica (pain syndrome; tingling/numbness/burning pain of outer thigh)
procedures of what areas that use a posterior lumbar plexus (psoas compartment) block ?
Hip
knee
anterior thigh
Needle size and gauge for completing a Lateral femoral cutaneous nerve block:
short: 3-4 cm
22 g
after careful aspiration, how much volume of LA is injected above and below the fasica lata of a lateral femoral cutaneous NB?
10-15mL of LA
In theory, direct nerve injury is possible, but in clinical practice this is one of the few nerve blocks:
for lateral femoral cutaneous NB
with no side effects or complications
Obturator Nerve is both a
motor and sensory nerve
- sensory: hip & knee joints, medial thigh
- motor: adductors of hip
Obturator Nerve block is most often performed in combination with
femoral and sciatic nerve blocks
… for complete anesthesia of the knee
What nerve block is required to complete anesthesia of the knee?
obturator nerve
obturator nerve often gets pinched in what position?
lithotomy
Landmark to identify in obturator block:
tip of the pubic tubercle
needle length required for obturator block:
10cm block needle — inserted until bone is contacted
what motor response is elicited in an obturator block?
thigh ADDuction
volume of LA injected in an aobturator block?
15-20 mL of LA
sciatic block is in combination with what two additional blocks to provide complete anesthesia and post-op analgesia for LE surgery?
- Lumbar Plexus
2. Femoral Block 3 in 1
the sciatic nerve is the continuation of the
upper division of the sacral plexus
sciatic nerve originates from the
lumbosacral trunk and is composed of
nerve roots L4-5, S1-3
Sciatic nerve innervates the muscles of the
posterior thigh
skin of the leg
muscles of the LE (MAINLY by tibial and peroneal portions of sciatic nerve)
Needle length for a sciatic block:
Long, 10 cm at perpendicular angle
volume injected in a sciatic block
25 mL of LA
what motor response is elicited in a sciatic block? What is PREFERRED for surgical anesthesia?
- Plantar or dorsiflexion
- Plantar flexion: distal ankle, foot, toes, or foot inversion
Major risk with sciatic nerve (popliteal approach) block?
vascular puncture
sciatic nerve divides into:
- Common Peroneal
2. Tibial
Posterior approach (popliteal) to sciatic nerve block needle length and gauge:
insulated 5-10cm
22g
volume of LA injected for a Posterior approach (popliteal) to sciatic nerve block
30-40ml
saphenous nerve may be blocked by injecting:
5-10mL of LA in a subcutaneous ring
from the medial aspect of the tibia to the border of the patellar tendon
saphenous nerve block is done with what size needle?
short 2 cm
distal to the tibial tuberosity and medially
Ankle block indications - it is used for both
analgesia and anesthesia
in an ankle block, avoid excessive LA volumes and avoid
epinephrine
(to avoid risk of ischemic complications
Avoid epi in: (4)
Fingers
Toes
Penis
Nose
An ankle block includes what 5 nerves?
- posterior tibial
- deep peroneal nerve
- superficial peroneal nerve
- Sural nerve
- Saphenous nerve (terminal branch of femoral)
** if the surgery does not require all 5 nerves to be blocked, then do not do it**
The only nerve NOT a part of the sciatic system in an ankle block is:
saphenous nerve
In an ankle block, in each injection, what is the amount of LA injected?
5mL x 5 injections
In a Brachial Plexus block, the higher up the block…
the greater the area covered
Name the 5 anatomic areas for blocking the brachial plexus:
- Paravertebral
- Supraclavicular
- Infraclavicular
- Axillary
- Blocking the specific terminal nerves
** how many cervical nerves are there?
8 cervical - only 7 cervical vertebrae , but 8 nerves
how many thoracic nerves are there?
12 thoracic nerves
how many lumbar & sacral nerves are there?
5 lumbar
5 sacral
Spinal nerves mneumonic:
“Breakfast at 8, Lunch at 12, Dinner at 5”
8 cervical
12 thoracic
5 lumbar/ sacral
**Total number of spinal nerves?
31
8+12+5+5+1 (coccygeal) = 31
**Each spinal nerve has an
Anterior and posterior root
- posterior roots form ganglia
- anterior roots join to form plexuses
Brachial plexus if formed by the anterior divisions of:
C5, 6, 7, 8, and T1 nerves
between the scalenes
Lumbar plexus if formed by the roots of
lumbar 1-4
Sacral plexus is formed by the roots of
lumbar 4-5, sacral 1-3 nerves
Is there are thoracic plexus?
no - except T1 in brachial plexus
and some T12 in lumbar plexus
Break down of the Brachial plexus:
- 5 roots
- 3 trunks
- 6 divisions
- 3 cords
As ________ leave the intervertebral foramina, they form, trunks, divisions, cords, and then terminal nerves
Nerve roots
Three brachial trunks and roots formed by
- Superior c5-6
- Middle C7
- Inferior C8-T1
- *all lie b/w anterior and middle scalene muscles
- all pass over lateral border of 1st rib under clavicle and divide into anterior/posterior divisions
How many brachial divisions are there?
6 divisions (at lateral edge of the 1st rib; behind clavicle)
- 3 anterior
- 3 posterior
How many Cords are in the brachial plexus?
3
-names for their relationship to the axillary artery
Lateral cord is the union of
anterior divisions of upper and middle trunks
Posterior cord is
all 3 posterior divisions
Medial cord is continuation of
anterior division of the inferior trunk
**Major nerve of Lateral cord:
Musculocutaneous nerve
-gives off lateral branch of median nerve and terminates as musc.
**Major nerve of Posterior cord:
Radial Nerve
-gives off the axillary nerve and terminates as the radial nerve
**Major nerve of Medial Cord:
Ulnar Nerve
-gives off medial branch of the median nerve adn terminates as ul. nerve
At the lateral border of pectoralis minor muscle, each cord gives off a large branch before terminating as a major
terminal nerve
Axillary nerve terminates as:
radial nerve
Medial head of median nerve terminates as:
ulnar nerve
Lateral branch of the median nerve terminates as:
musculocutaneous
**While not a major nerve of a cord, it is made by 2 large branches from the lateral and medial cords:
median nerve
Interscalene block optimal for :
procedures of shoulder and upper arm
Supraclavicular approach best for:
entire arm, including hand
Infraclavicular approach indicated for:
procedures of
- hand,
- forearm,
- elbow, and
- upper arm
Axillary approach indication for
procedures UP TO THE ELBOW
**Which B.Plexus approach is not best for hand?
interscalene
** which B.Plexus approach is not ideal for shoulder?
supraclavicular
which B.Plexus approach does not include the bicep or tricep?
infraclavicular
which B.Plexus approach does not include the forearm?
Axillary
Which B.Plexus approach is most appropriate for shoulder surgery?
interscalene
Interscalene block is not recommended for surgery of
- hand (or any surgery…
- below the level of the elbow
**supplementary ulnar block may be required
Interscalene block is indicated for surgical procedures on the clavicle, SHOULDER, elbow and upper arm with the exception of the
medial aspect of the arm
For complete surgical anesthesia of the shoulder, a supplemental block of the
superficial cervical plexus block is needed
***The Ulnar nerve is frequently not blocked in this block:
Interscalene block
this block is NOT appropriate for surgeries distal to the elbow
Interscalene block
Contraindications or considerations for an Interscalene block:
- Contralateral phrenic nerve paralysis
- Recurrent nerve paralysis (severe pulm dx)
- Contralateral pneumothorax
- Pt. requires a bilateral block
- Respiratory compromise
Landmarks for interscalene:
” I = CCCE.IT” (read as “I SEE IT”) I = interscalene
- Clavicle
- Clavicular head of the Sternocleidomastoid muscle
- Cricoid cartilage
- External jugular vein
- Interscalene Groove
- Twitch response to DELTOID
volume of LA injected for interscalene block?
20-30mL
SE’s of Interscalene block:
- Horner’s Syndrome (transient)
- Phrenic Nerve block- ipsilateral (C3-5)
- Recurrent Laryngeal Nerve block
- Compression of Carotid artery lumen
RLN paralysis presents as
hoarseness
Major complication of Interscalene block:
Intravascular injection of VERTEBRAL artery –> CNS Toxicity
- subarachnoid injection (total spinal)
- epidural injection (high epidural)
- pneumothorax
How do you tx a pneumothorax?
needle decompression
- 18G
- 2 IC space; midclavicular
Supraclavicular approach of a Brachial Plexus block occurs at the level of:
the 3 trunks
-where brachial plexus is most compactly arranged; “the spinal of the arm”
advantages of Supraclavicular approach?
**No danger of missing peripheral or proximal nerve branches b/c of failure of LA spread
- Low Vol LA req.
- Quick onset
- Arm can be in any position
Major disadvantage of supraclavicular approach?
**Pneumothroax (MAJOR RISK)
- difficult to perform and/or teach
- need experience
Contraindications of Supraclaviular approach:
- same as interscalene
- Contralateral phrenic nerve paralysis
- Recurrent nerve paralysis (severe pulm dx)
- Contralateral pneumothorax
- Pt. requires a bilateral block
- avoid bilateral phrenic NB
- avoid pneumothorax - Respiratory compromise
pneumothorax occurs at what percentage in a supraclavicular approach? what decreases this?
- 5 - 5%
- improved safety with U/S
Indications for a supraclavicular approach?
- procedures AT or DISTAL to the elbow
- Arm
- Forearm
- Hand
**a supraclavicular approach is not ideal for? why?
It also spare what?
**Not ideal for shoulder surgery - not adequate block of the suprascapular and axillary nerves.
-Spares: distal branches. DOES NOT BLOCK ULNAR
hyperechoic =
brighter areas = think bones / RIBS
hypoechoic =
lighter areas = nerve plexus
LA volume injected for a supraclavicular approach:
In 5mL increments while visualizing LA spread around brachial plexus
20-30mL In-plane
30-40mL Out of Plane
when you’re looking for the “snow man” to what are you looking for?
brachial plexus
SCL block in plane with US technique, what needle size is used?
22g
If using PNS in a SCL block, what motor response are you looking to elicit?
arm, forearm, or hand
An Infraclavicular approach blocks the brachial plexus at the level of
the cords
Avoid using an infraclavicular approach in pts with:
- vascular catheters in SCL region
- ipsilateral pacemaker
Infraclavicular approach is excellent for procedures
distal to the elbow
The terminal nerve that is blocked by an infraclavicular approach?
musculocutaneous
is the upper arm and shoulder anesthetized with an infraclavicular approach.
no
needle length for infraclavicular approach:
8cm
motor response elicited with infraclavicular PNS stimulation?
finger flexio or extension
LA vol injected for infraclavicular apporach:
20-30ml
Advantages of Axillary block:
- Less risk of major complications
- Suitable for ER and OP use
Primary disadvantage of axillary block?
extent of anesthesia is insufficient for shoulder or upper arm surgery WITHOUT using LARGE volumes of solution
relationship of nerves to axillary artery (at the axillary level):
Median nerve:
anterior to the axillary artery
relationship of nerves to axillary artery (at the axillary level):
Ulnar nerve:
posterior to the axillary artery
relationship of nerves to axillary artery (at the axillary level):
Radial nerve:
Posterior and somewhat lateral
For an adequate block, you must additionally block what nerve in conjunction with the axillary block?
musculocutaneous
-because it is outside the neuro sheath
Musculocutaneous block is essential to complete the anesthesia for the
forearm and wrist
-commonly included when performing an axillary blcok
Trans-arterial axillary technique, has fallen out of favor due to what?
- arterial puncture (axillary artery)
- inadvertent LA injection
- risk of hematoma
- pressure must be held for 5mins
LA used for brachial plexus
- can epi be used?
yes
-may be used w/or w/o epinephrine 1:200,000
what LA is mostly used for B.Plexus blockade?
bupivacaine
0.375-.05% Bupivacaine or Ropivacaine
1-2% Mepivacaine or Lidocaine
1 % etidocaine
in regards to LA:
when larger volumes are used….
… lower concentrations are also used.
Digital nerves are the distal continuation of both the
median and ulnar nerves
solutions for digital blocks should NEVER contain
epi
**Never use epi in:
fingers, toes, penis, nose
in a digital block what size and gauge are used?
short
23-25g
when performing a digital block, how much and where is LA injected?
2-3mL of LA without Epi
on each side (both the dorsal and ventral branches of the digital nerve is carried out bilaterally)
Supinate =
palm of hand / anterior / ventral
Pronation =
back of hand / posterior/ dorsal
Digital complications include not exceeding maximum volume of LA on each side? why?
2 mL on each side (4 mL total)
-can get compartment syndrome
Max. tourniquet time for a digit:
15 mins
Patients to use a tourniquet with caution in:
- raynaud’s
- PVD
best indication for a bier block:
used for brief minor surgery (up to 1 hour) of an extremity
Carpal tunnel release is usually performed via this block
beir block
most common complication with a beir block?
systemic toxicity
-b/c a potentially toxic dose of LA can be injected into the central circulation.
You never proceed with a beir block without what?
an IV in the opposite arm
emergency medication administration
Always check what before a beir block procedure?
the Tourniquet pressure tubing valves apparatus
Beir block needle size:
Where is it introduced?
small IV catheter 22g
-introduced in the dorsum of the pts hand of the arm to be anesthetized
for a beir block, the extremity is wrapped in esmarch bandage from _____ to ______.
distal to proximal.
the proximal cuff is inflated and maintains a cuff pressure at:
150mmHg above SBP
- upper: 250 mmHg
- lower: 350-400mmHg
how is functionality of the cuff checked for a beir block?
for occlusion of the radial artery pulse
-check both cuffs
when the esmarch bandage is removed, the pts arm is returned to horizontal position. the arm should be:
stark white/pale
completely w/o blood or circulation
What LA is used in a beir block?
How much is administered?
Injected over how long?
Anesthesia is established after?
-0.5% Lidocaine Administer: -25ml for FA -50ml for Arm -100ml for thigh -popular dose is 40ml
Over: 2-3 mins
Anesthesia in: 5-10 mins
The proximal tourniquet is left inflated in a beir block until
the pt c/o of tourniquet pain (~ 20-30mins)
*often can give versed or a little propofol to help them relax
When is the distal tourniquet inflated in a beir block?
when the proximal is deflated.
-distal cuff should be over an anesthetized area
in a beir block, when anticipated duration of the surgery is 20 mins or less what should be done?
the proximal distal tourniquet should remain inflated for at least that period of time (at least 20 mins)
LA that are NOT used in a beir block?
bupivicaine or chloroprocaine
Due to the risk of /and single m/c complication of systemic toxicity (due to leak or premature tourniquet release), what must we ensure is done for SAFETY in all beir blocks:
- *HAVE AN IV LINE IN THE OPPOSITE ARM
- always check tourniquet pressure-tubing-valves before procedure
- appropriate monitoring (HR, BP, O2, etc)
- slow tourniquet release
Every pt receiving a major conduction nerve block should (2):
- have IV access
2. monitored for timely detection of systemic toxicity of LA
Larger doses of LA for major conduction or plexus blocks are routinely monitored for signs of LA toxicity for
30 mins after block placement
Although a toxic reaction occurs during or immediately on injection of LA in almost all instances, the PEAK serum level of LA occur:
20 mins following injection
**This block results in the highest blood levels of LA per volume injected of any block in the body:
Intercostal block (peripheral block of the trunk)
-care must be taken to avoid toxic levels
**This block has one of the highest complication rates of any peripheral nerve block:
Intercostal block (peripheral block of the trunk)
- d/t proximity of intercostal artery and vein
- risk of iv LA injection
- pneumothorax (underlying pleura)
Intercostal block (peripheral block of the trunk) needle size and gauge:
22-25g
short - 3-4cm needle
following aspiration of an Intercostal block (peripheral block of the trunk), what should you see in your syringe?
nothing!
TAP Block is :
transversus abdominis plane block
-peripheral block of the trunk
Main use of TAP blocks?
analgesia
**indications for TAP block:
- *C/Section
- hernia
- appendectomy
- abdominal hysterectomy
- prostatectomy
TAP blocks can be given bilaterally for: (2)
- midline incisions
2. laparoscopic procedures
TAP Blocks can be used for post-op analgesia for procedures below
the umblilicus
**What are the nerves targeted in the TAP Block?
- Subcostal -T12
- Ilioinguinal -L1
- Iliohypogastric - L1
**For a TAP Block, the goal is to inject LA b/w the internal oblique and transversus abdominis muscle targeting the :
spinal nervers in T7-L1
TAP blocks can provide intra-op and post op analgesia for up to
36hrs
**3 planes are identified in a TAP block:
- Transversus Abdominis (LA injection site)
- Internal oblique
- External Oblique
“TAP: TIE”
on u/s, muscles appear as striated _____ structures with ____ layers of fascia at their borders.
Striated: hypoechoic (darker)
Hyperechoic (brighter) layers
needle size and gauge for TAP block
long, 10cm
21 G
volume of LA injected for a TAP block
20-30mL
On LA injection during a TAP block, what is observed on US?
separation of the 2 fascial layers – LA vol should expand the plane
Normal PT, INR, PTT levels
PT 11-14
PTT 25-35
INR 0.8-1.2 (<1.5 INR OK)
For a skin wheal what % and amount of lidocaine is used?
1% and 3mL
**Cervical plexus is innervated by 4 cutaneous branches - what are they?
C2-C4
- C2 Lesser occipital and
- C2 Great Auricular
- C3 Transverse Cervical
- C4 Supraclavicular
When do you want to use a Retrobulbar block?
When you do not want the eye to move
Before you push meds/LA, what do you do?
ASPIRATE
With the pt supine and looking up (@ ceiling) what needle size and gauge would you use for a retrobulbar block?
25-27 gauge
-inserted 0.75 - 1.25 inch
after negative aspiration, how much LA would you inject for a RB. Block?
2-4ml
**what nerve supplies the airway mucosa from the level of the epiglottis to the distal airways?
vagus nerve
**What nerve, a branch of the superior laryngeal nerve, supplies the larynx above the vocal cords and the lower part of the pharynx?
• The internal laryngeal
**what provides motor innervation to the cricothyroid muscle?
• The external laryngeal branch
**what nerve supplies the larynx below the vocal folds and the upper part of the esophagus?
• The recurrent laryngeal nerve
**what nerve is primarily parasympathetic but also contains some cervical sympathetic fibers and motor fibers to the laryngeal muscles?
• The Vagus nerve
When performing a SLN block what size needle is appropriate?
25g
**When performing a SLN block how would you know if you are TOO deep?
when you aspirate before injection and get AIR
AIR = Too deep
How much 1% lidocaine is deposited in a SLN Block?
Where? (there are two locations)
- 2ml within the Thyrohyoid membrane (below/ internal)
- 1-3ml as you withdrawal needle above
analgesia of the globe generally precedes:
akinesia of the eye muscles
Translaryngeal (Trans-tracheal) block is also known as:
recurrent nerve block
-provides anesthesia of the airway mucosa below the cords and laryngeal mucosa above the vocal cords and epiglottis
what sized needle is inserted in the midline into CTM, aspirating as needle advanced. (slightly caudal) in a RLN block?
22 ga or 25 ga
***before 3-4 mL of 4% lidocaine is injected rapidly at end of expiration and the needle withdraw for a RLN Block, what must be done?
Once AIR is freely aspirated
Most common complication of an ocular block?
intra-arterial injection: LA toxicity
Oculocardiac reflex afferent and efferent responses:
- afferent = via the ophthalmic branch of cranial nerve V (trigeminal nerve)
- efferent = via cranial nerve X (vagus nerve)
- leads to severe bradycardia and potentially hypotension, atrioventricular block, ventricular ectopy, and rarely asystole