upper and lower blocks Flashcards
common PNB goals
post op pain control
reduction/elimination of necessity for parenteral opioids and pain adjuncts
avoidance of GA
avoidance of airway elimination
reduction of GA side effects (cardiac effects, lung irritation, and PONV)
the use of ___________ is increasingly seen as standard and demonstrated to increase safety, improve efficacy, and reduce untoward events
ultrasound
contraindications for regional anesthesia
patient refusal
coagulopathy
infection at site of block
tolerance to procedure itself
___________ may prevent use depending on specific block and severity of the abnormal lab value
coagulopathy
coagulopathy would prevent a _____ block but not a _____ block
central
digital
identification of coagulopathy risk remains a key component of the patient history rather than
reliance on lab testing alone
consideration of the potential for uncontrolled _________ is a primary concern
hemorrhage
infection at the site of the block might decrease ________ of the block due to the __________ of the tissue being below ______ values which increases the __________ portion of the drug and does not allow nerve entry
efficacy
pH
pKa
ionized
______ to the procedure itself and a non-general anesthetic must be considered when deciding a plan
tolerance
can the patient with an altered mentation tolerate lying on the OR table for the procedure ________ or _______ if a regional anesthetic is used instead of GA
sedated or unsedated
further risk associated must be explored, if a pneumothorax would be life threatening, a ____________ block should probably be avoided
supraclavicular
risk for ______ _______ should always be kept in mind when combining blocks and _____ administration, as surgeons may also be introducing ______
LA toxicity
LA
LA
questions to ask that are key to block selection
- what surgical area needs coverage?
- are there significant risks?
- note specifically which blocks include the shoulder
- note specifically which blocks cover anterior and posterior aspects of the leg
_______ _______ _________ and ________ _______ are the most common methods of approaching the nerve, with landmark techniques falling out of favor r/t higher complications and greater failure rates
peripheral nerve stimulation and ultrasound guided
with any technique, it is critical to know what _______ _______ should be anesthetized and ensure that the nerve blockade is adequate for that space
anatomical structures
the actual needle insertion should occur only after ruling out _______, ______ _______, and consideration of ________ ________
contraindications, informed consent, and consideration of supplementary sedation
a skin prep should be utilized prior to localization and needle placement; a __________ and ________ mixture is commonly used bc __________ is considered neurotoxic
chlorhexidine and alcohol
betadine
for actual needle placement, a small injection of ____-____ of ___ __________ using a ____ or ____ gauge needle may be used to numb the skin at the block needle insertion site
0.5-1 mL
1% lidocaine
27 or 30 gauge needle
for nerve stimulation, a _____ _____ system is used
two lead system
a ________ surface lead is connected to an EKG sticker while the ________ lead is connected to the electrical attachment of a nerve stimulating needle
positive
negative
block need design has a ________ shape as opposed to the long bevel of a ________ needle
conical
hypodermic
this design reduces the likelihood of impaling the nerve by _________ rather than _________ the fiber
displacing
piercing
additionally, the _________ action of beveled needles has potential to transect _______ and is uncommon for blocking needles
shearing
fibers
finally, block needles have an ________ property designed to transfer the electrical stimulus to the ______ ___ ___ _______ rather than along the _____ ______
insulating
tip of the needle
full length
this allows the clinician to recognize _____ location based on muscle twitch response
tip (only)
further quantification of proximity of the needle tip to nerve is accomplished by adjusting the _______ _______
milliamp stimulation
a qualitative appreciation of muscle movement is used to
gauge the distance from the nerve
similar muscle contraction response with ________ _______ indicates the needle tip is approaching the nerve
decreasing milliamps
target range for proximity is satisfactory muscle response at _____-_____
0.3-0.5 mA
a greater amount of mA required suggests the needle tip is
too far from the target nerve
a persistent muscle response at less than ______ increases the likelihood of ______
0.3
intraneural injection
in order to determine the needle is in the correct location, it is helpful to know what nerve controls what muscle response less “any” muscle movement could be interpreted as
correct needle placement
use of ultrasound improves _______, ______, and _______ with block function
safety
efficacy
satisfaction
the ability to identify nerves allows more _______ ______ under visualization thereby achieving a more _______ and _______ block while necessarily avoiding adjacent structures and reducing ________ _______ risk
precise placement
complete and dense
intravascular injection
a ______ ______ of the structure to be scanned should ________ the placement of the probe
cognitive visualization
precede
a _______ _______ ______ or sterile ______ ______ must be used to interface the probe with the tissue
water soluble lubricant or sterile ultrasound gel
use of a _______ _______ _______ is recommended to avoid contamination of the needle or injection space with a non-sterile probe
sterile probe cover
anatomy of the nerve can be identified in the _____ _____ and centered on the screen
short axis
then the needle can be inserted toward the nerve from the side of the probe maintaining a short axis of the nerve but a _____ _____ of the needle
long axis
the advantage of long axis on the needle is a full view of the needle is maintained throughout the procedure reducing the chance that the needle tip is _______ “_____ ___ ______”
lost “out of plane”
once needle is adjacent to the nerve, _________ followed by the injection of the _____ is visualized on the screen
aspiration
LA
when viewing a 3D structure with a 2D image, the clinician has to choose between or alternate between a _________ ________ or _____________ view
cross section or longitudinal
short axis is called the
SAX
long axis is called the
LAX
the SAX and LAX are created by “_______” or _________ the probe over the anatomy
spinning
rotating
ultrasound emits a beam that lies only _______ ______ the probe
directly under
one technique to assist with this to identify structures in _____ first and then rotate to _____
SAX
LAX
________ is essential to achieving proficiency
practice
many of the upper extremity blocks involve accessing the
brachial plexus
plexus larger to smaller elements of the plexus are noted as:
ventral rami (roots) > trunks > divisions > cords > branches
real texans drink cold beer
a key value in knowing the divisions is the ability to determine
which nerves will be affected based on the site of injection
4 classic approaches to deliver LA to brachial plexus
interscalene blocks - trunks
supraclavicular blocks - divisions
infraclavicular blocks - cords
axillary blocks - branches
ideal placement is inside the _____ ______ that surrounds the nerves, however, given sufficient ______ and ______
fascia sheaths
time and dosing
LA that is absorbed prior to ______ ______ will generate an effect
vascular uptake
interscalene provides easy access with fewer risks as as coverage of the _________. it also does not generally cover the _____ _____/ _______ to the hand
shoulder
ulnar nerve/sensory to the hand
the supra and infraclavicular do not cover the shoulder and are much closer proximity to the _____ ____ of the ______
pleural space of the lung
infraclavicular and axillary provide increased coverage of the ________ and _______ ______ compared to the interscalene
forearm and musculocutaneous nerves
in the case of specific nerve distributions, or plexus blocks that need additional focused coverage, blocking specific nerves for this extra coverage may be accomplished through ______ ______ with or without ______
direct localization
ultrasound
volume of injection is commonly
about 20 ml
one element to be aware of is ______, but with _________ approach there is no risk for this
pneumothorax
axillary
______ _______ of the diaphragm is another complication of brachial plexus block. this is related to close proximity of the _____ ______
ipsilateral hemiparesis
phrenic nerve
this should be of particular concern in any patient where surgical or existing physiologic compromise might cause _______ ______ _______
inadequate spontaneous ventilation
______ ______ is a known side effect from sympathetic blockade
horner’s syndrome
uptake of LA into the head and neck may result in sympathetic blockade to nerves affecting ______ _______
facial structures
________, ________, and ________ are the features of horner’s syndrome
ptosis, miosis, and anhidrosis
drooping of one eye, pupil constriction, absence of sweat on the affected side are self limiting for the duration of the block
inadvertent _____________ __________
non-compressible hemorrhage
because in these blocks, the vasculature intermittently weaves around bone structure, the potential for a needle stick to cause bleeding that cannot be _______ _______ and should warrant consideration of ______ vs ______ (particularly with anticoagulation)
directly compressed
risk vs benefit
interscalene approach: locate by identifying the sternal head of the __________ muscle, moving laterally to clavicular head, then further lateral to the space between the _______ and _______ ________ muscle
SCM
anterior and middle scalene
all this take place vertically at the level of the cricoid cartilage which corresponds with
C6
a posterior and inferior directed needle approaches should address the plexus in perpendicular fashion, envisioning the nerves leaving the ______ and following down the _____
neck
arm
axillary approach - landmark technique has fallen out of favor as it is less _______ and involves intentional __________ of the ________ _______ to determine the location of the needle
precise
puncture of the axillary artery
nerve stimulation may be _______ by some measures, but still involves a decreased measure of ________
safer
precision
for ultrasound approach, it is important to have a concept of the layout of the _______ within the ______
anatomy
axilla
median nerve is ___________, closest to ultrasound probe and skin where the needle goes. it is located adjacent to the ____________ muscle as a landmark. it is anterior
superficial
coracobrachialis
________ is opposite the median on the deep side of the axillary artery
radial
musculocutaneous nerve is on the ______ side, is hyperechoic
biceps
ulnar is opposite side of the ______ ______ and opposite of the ________ _______ on the triceps side. it is posterior
axillary artery
median nerve
recall the MC nerve generally requires _______ _______ by a _______ _______ for interscalene and axillary
selective blockade by a field block
the ______, _______, and _______ nerve can be selectively blocked at the elbow with any of the previously mentioned approaches
ulnar, radial, and median nerve
caution with ________ only approaches due to risk of direct ________ ________
anatomic only
nerve trauma
risk of vasculature compromise generally weighs against the use of _________ below the elbow
epinephrine
a general volume maximum should be ______ noting the risk of ________ _________ / _________ particularly with ulnar blockade
5 mL
compartment development/entrapment
Bier block technique does not require any special equipment other than reliable ________ _________ as the _______ ______ is injected through an ____ site
surgical technique
local anesthetic
IV
some limitations of a bier block include:
tourniquet must be left inflated for at least 20 mins
duration of procedure shouldnt last longer than an hour (2 hours may be possible with special technique)
IV must be started in operative arm as distal as possible
arm must be able to tolerate an arterial tourniquet
methods to increase the duration/density of the block includes:
additives and field blockade of the upper arm to diminish tourniquet pain
additives may essentially include any agent that would otherwise be acceptable for IV administration including:
clonidine
toradol
ketamine
decadron
fentanyl
bier block chronology
small gauge IV in operative arm
placement without inflation of tourniquet on upper arm after padding is in place
notation of radial pulse
elevation of the arm
esmarch bandage exsanguination
inflation of tourniquet
confirmation of the absence of the pulse
**injection of 50 ml of preservative free 0.5% lidocaine
removal of the IV
tourniquet must be on the _______ and lidocaine must be free of _______
humerus
epinephrine
use of forearm tourniquets may be used occasionally however the incidence of failure is higher due to greater difficulty in _______ ________ against two bones
arterial occlusion
the use of a double tourniquet allows a ____ _____ to occur naturally from under a portion of the tourniquet which allows for temporary _____ _____
field block
pain relief
at the beginning of the case, the _______ tourniquet is inflated and when the tourniquet pain is noticed, the _______ tourniquet is inflated
proximal
distal
then after confirmation of the ______ inflation, the ______ ________ is deflated as the painful cause
distal
proximal tourniquet
to further decrease tourniquet pain, cast padding or equivalent can be used _______ the _______ to avoid ______ _____ injury
under the tourniquet
soft tissue
interscalene analgesia to
shoulder and upper arm
supraclavicular analgesia to
entire upper extremity distal to the shoulder
infraclavicular analgesia to
elbow and below
axillary analgesia to
distal to elbow
intercostal analgesia to
chest and upper abdominal wall
TAP analgesia to
anterior abdominal wall
femoral analgesia to
anterior thigh and knee, medial aspect of the lower leg
fascia iliaca analgesia to
hip, femoral shaft and knee
sciatic analgesia to
below the knee sparing the area of the medial side of the lower leg (saphenous distribution)
popliteal analgesia to
below the knee sparing the area of the medial side of the lower leg
ankle analgesia to
the foot and distal ankle
the value of an intercostal block is _____ duration (several hours) block that is not _____ to perform and can reduce surgical ______ or allow improved efficacy of painful _______
medium
complex
pain
respirations
the block is performed in the ___-_____ line and allows for blockage of the intercostal level of injection
mid-axillary
because intercostal uptake is one of the ______ sites for LA, caution should be taken to avoid _____ _____
highest
toxic doses
_______ may be added to reduce vascular uptake even if it does not increase _______ of _______
epinephrine
duration of action
_____, ______, ______ in descending order, follow the inferior border of the rib and injection should be by ___-___ml under the _______ border of the rib
vein, artery, nerve
2-3ml
inferior
_______ is a prominent risk
pneumothorax
use of a _____ needle rather than __________ needle can reduce this risk along with slow and methodical movements
block needle
bevel hypodermic
the inferior edge of the rib should be passed only by ___–___ before injection
2-3mm
TAP block provides analgesia to the _______ ______ (if done bilaterally) suitable for most open and laparoscopic procedures as a support for a mixed anesthetic technique or for post-operative pain
abdominal compartment
it can be done ____ to surgical case or _____
prior
after
the _____ _____ _____ that surround the abdominal cavity are identifiable on ultrasound
3 muscle layers
spread of LA between the ____ _____ and _____ ______ muscle layers creates a unilateral blockade of nerves _____-_____ (5 levels)
internal oblique
transversus abdominis
T9-L1
a ____ ml bolus (each side) can be injected incrementally under direct _________ guidance
20 ml
ultrasound
________ are sometimes used as with other PNBs
additives
caution is used to avoid entry into the _______ ______
abdominal compartment
limitations in value are the inadequate spread through the ______ _____ in which muscle or subcutaneous uptake affect the ________ of _________ and ______.
fascial plane
duration of action
levels
for each of the blocks described, consideration of ________ is appropriate
sedation
further, it is essential to provide ____ ____ prior to ______ ______
skin prep
needle insertion
this is commonly done with a _________ and ________ mixture (______)
chlorhexidine and alcohol mixture (chloroprep)
________ should be used with caution as it is neurotoxic
betadine
the use of _______ injection (____ _____) for the block needle placement is appropriate
topical injection (skin wheel)
0.5-1ml of ___ ______ is common
1% lidocaine
avoidance of _________ of the ultrasound probe can be accomplished through several techniques that should be performed
contamination
separation of the plane between the internal oblique and TA muscle is indicative of
an appropriately placed block
moving the probe _____/_____ and ______/______ along the abdominal cavity space is often needed to identify layers clearly
anterior/posterior
superior/inferior
cervical blockade is used occasionally for procedures such as ______ _______
awake endarterectomy
cervical blockade is considered an _______ ______ with an increased risk of ________
advanced technique
complications
the likelihood of complications includes such events as _______ _____ injection, _____-______ injection, _______ ______ paralysis (temporary), __________ injection, ______ and ______ blockade
vertebral artery injection
sub-arachnoid injection
phrenic nerve paralysis
intravascular injection
vagal and RLN blockade
these should ONLY be performed:
unilaterally
they address the cervical roots of ____, ____, _____
C2, C3, C4
mid __________ muscle on the ________/_______ aspect is the point for injection in a field block technique using 10-20 mls
SCM
posterior/lateral
development of thoracic wall analgesia (chest wall blocks) can be accomplished by an ever expanding host of individual _____ blocks, _____ blocks, and nerve ______.
nerve
plane
bundles
_______ _______ provide a means of ongoing relief (due to catheter) at levels that can be adjusted with volume
thoracic epidurals
risk for _______, _______, and _______ and ______ due to thoracic level _________ are all risks
infection, bleeding, and hypotension, and bradycardia
cardioreceptors
thoracic epidurals commonly performed using _________ approach
paramedian
first, identifying the level of the block to be performed , commonly the surgical level for a _________ would be the level of insertion
thoracotomy
the transverse process is identified and a loss of resistance technique is used to identify the _______ ______ before placing the catheter
epidural space
________ nerve blocks can be performed as a ______ block to cover the anterior wall and can be used for _____________ work
pectoralis
plane
thoracotomy
an ultrasound is used at the origin of the pec near the anterior ______ ______ to identify muscles in short axis and LA is injected between the _____ ______ and _____
axillary line
pec major and minor
paravertebral blocks are similar to the thoracic epidural except they are _____ ______ techniques
single injection
the transverse process is identified at the target level (generally, ______ ______ are injected)
several levels
the spinal or epidural needle is inserted to the transverse process and “______ ______” the process to an additional ______ of depth
walked off
1 cm
further advancement significantly increases the likelihood of ______ ______ access and more importantly the ________ access
epidural space
intrapleural
_____ per level is generally acceptable
5 ml
as with intercostal blocks, uptake is fairly rapid and ___ _____ durations of effective analgesia is to be expected
4 hours
________ ________ _______ block is a relatively new block that accomplishes similar effects as a paravertebral block and PEC block but with markedly simpler approaches and with _____ risk and ______ success rate
erector spinae plane block
less risk
higher success
the idea of the plane block is that it spreads the LA across a space, between ____ ______ much like potential space between quilts on a bed
2 structures
volume ______ the spread and absorption into the spinal nerves along the path which result in clinical effect
increases
selection of lower extremity blocks is consistent with upper extremity blocks in that the nerves to anesthetized must be _______ with the ______ _____
matched with the surgical field
lateral femoral cutaneous nerve
L2/3 - lateral thigh
obturator nerve levels ______, ______ to adductor muscles of thigh and ______ to _______ thigh
L2/3/4
motor
sensory to medial thigh
femoral nerve levels _______, separates to ______/_______ limbs at the _______ ligament
L2/3/4
separates to anterior/posterior limbs at inguinal ligament
fem nerve block is a simple block providing pain relief to the _______, primarily ______ portion.
knee
anterior
the nerve is approached _______ for the femoral artery and ______ the inguinal ligament using ultrasound or nerve stimulator
laterally
below
no less than ______ of LA (___-___ ideally) is used for the block to secure adequate spread around the nerve
20 ml
20-30 ml
fascia iliaca compartment block provides ________ nerve coverage but adds reliable coverage of the _______ _______ _________ nerve
femoral
lateral femoral cutaneous
the addition of this blockade aids in _____ management of ______ sx
pain
hip
ultrasound guidance to the _____ ______ is followed with guidance above the _______ ______ and then injection of LA
fascia lata
fascia iliaca
the femoral nerve anatomy is adjacent to this facial plane and femoral nerve blockade occurs by default with this block; it simply has the additional lateral coverage by traveling along the _____, to the _____ _____ _____ nerve
plane
lateral femoral cutaneous nerve
sciatic block covers _____ ______ of the leg not covered by the fem nerve
opposing portions
______ ______ and lower _____/_____ coverage is supplied by the sciatic which later becomes the tibial and common peroneal nerve
posterior thigh
leg/foot
complete anesthesia of the leg requires addition of this block opposed to ______ only
femoral
for mid-level coverage, the sciatic is approached in the _____, while ankle coverage may be approached at the _______ ______ (______ block)
hip
posterior knee (popliteal block)
nerve stimulation should address both the _____ and ______ distributions and LA admin at each site
tibial and peroneal
tibial responses should be ________
plantar flexion
peroneal distribution should cause ________
dorsiflexion
adductor canal block (______ nerve) is a distal approach to the ______ nerve
saphenous
femoral
it decreases the effect of the ______ _______ and ______ thus allowing more focused blockade of the knee
proximal branches and hip
For total knee blockade, this approach increases the likelihood of ability to ______ _______ as it does not affect the ___.
ambulate early
hip
The approach is mid-thigh and utilizes the _____ _____ as a landmark.
femoral artery
popliteal block can be performed to cover the _____ _____ and _____ for total anesthesia coverage
lower leg
ankle
the sciatic divides into the _______ and _______ nerves approx. ______ above the bend in the knee
tibial and peroneal
10 cm above bend in knee
flor blockade, the patient in the ______ position can be blocked with nerve stimulation or ________ guidance
prone
ultrasound
the nerves are lateral to the ______ and ______ and join superiorly above the knee
vein and artery
a _____ injection around the nerve covers this block
20 ml
if select blockade of the ankle is desired and cant/shouldnt be achieved by popliteal block, the _____ nerves of the ankle can selectively be blocked for coverage
5
the five nerves are:
deep peroneal
saphenous
posterior tibial
sural
superficial peroneal
deep peroneal
just above ankle, nerve slightly lateral to the anterior tibial artery
saphenous
medial side anterior to malleolus
post tibial
located just posterior to the posterior tibial artery
sural
on lateral side, post to malleolus, this nerve is blocked in mirror to post tibial
superficial peroneal
on lateral side anterior to malleolus
