Ultrasound-Guided Truncal Blocks Flashcards
What is the goal of truncal blocks?
Place LA around nerves but aren’t anesthetizing specific nerves
Using anatomy to provide LA to nerves that lie within muscles/ fascial planes
How do truncal blocks differ then peripheral nerve blocks?
peripheral nerve blocks target specific nerves while truncal blocks target nerves in fascial planes
What are the 5 thoracic blocks?
PECS 1 PECS 2 serratus anterior plane block paravertebral block intercostal nerve block
What are the four abdominal blocks?
rectus sheath
transverse abdominis plane (TAP)
erector spinae
quadratus lumborum
What are the indications for the PEC 1 and 2 block?
analgesia for breast surgery
Describe PECS 1 block
anesethetize medial and lateral pectoral nerves ( innervated pectoralis muscles)
high frequency linear array transducer placed in parasagittal orientation at level of coracoid process; rotate transducer to a cephalad medial and caudad lateral orientation to visualize thoracoacromial artery
Describe PECS 2 block
extension of PECS 1
also blocks upper intercostal nerves
What is PECS 1 and 2 an alternative too?
paravertebral block or thoracic epidural
What blocks reduce the risk of pneumothorax and spinal?
PECS 1 and 2
What nerves innervate the lateral cord?
C5-C7
What nerves innervate the medial cord?
C8, T1
What position is the patient in for PECS 1?
supine with arm abducted
What do you need to identify in a PECS 1 block?
costal margins, pectoralis major (PM), pectoralis minor (Pmi), serratus muscles
How is the needle inserted for a PECS 1 block?
in-plane, cephalad to caudad, until the tip pentrates the fascia between PM and Pmi
What is medial to the Pmi muscle before entering the PM muscle
lateral pectoral nerve
What does the lateral pectoral nerve communication and supply?
communicates across axillary artery with medial pectoral nerve and supplies the Pm
Where does the medial pectoral nerve arise?
medial cord fibers from C8 to T1 behind the axillary artery at level below the clavicle
passes through the Pmi and then enters and innervates PM
What are both pectoral nerves deep to?
pectoral major muscle
Where do you place the transducer for a PECS 2 block?
slide transducer caudad to level 3-4th rib and angle inferolaterally until the Pmi and serratus anterior muscles are identified
Where are the two injections for PECS 2 placed?
infiltrate two fascial compartments between pectoral nerves and under pectoralis minor muscle
Inject: between Pm and Pmi muscles (pectoral nerves)
between Pmi and serratus anterior muscles (intercostal branches for axilla and chest)
What position is the patient placed in for PECS 2 muscle?
supine, arm abducted 90 degrees or at side
Where is the first injection anatomically for PECS 2?
between pectoralis major and pectoralis minor
Where is the second injection anatomically for PECS 2?
anterior axillary line of level 4th rib, 1-3 cm for second injection and 3-6cm for second injection
During a PECS 2 block, what angle can the transducer be to help visualize the axillary artery and vein and second rib?
transducers can be angled infero-lateral
How is the serratus plane block different then the PECS 1 and 2 block?
more lateral and posterior then PECS 1 and 2
Where is the serratus plane block performed?
axillary region
Where is LA anatomically injected for serratus plane block?
between serratus anterior and latissimus dorsi muscle
What are indications for serratus plane block?
breast surgery, thoractomy and rib fracture
What anatomic structures are found in a serratus plane block?
intercostobrachial nerve, lateral cutaneous branches of intercostal nerves T3-T9, long thoracic nerve and thoracodorsal nerves are in compartment between serratus anterior and latissimus dorsi muscles
What are the two main anatomical landmarks for serratus anterior plane block?
latissimus dorsi and serratus anterior muscle
What artery runs in the fascial plane of the serratus anterior plane?
thoracodorsal artery
What is the patient position for serratus anterior plane?
lateral or supine with arm forward
Where do you place the transducer for a serratus anterior plane block?
linear array transducer across axilla to identify latissimus dorsi and thoracodorsal artery
What are indications for paravertebral block?
perioperative analgesia for thoracic, chest wall or breast surgery, pain management of rib fractures
What does the paravertebral block target?
paravertebral space that contains spinal nerves, branches and sympathetic trunk
What is the paravertebral space?
wedge shapped area formed medially by the vertebral body, inferiorly by parietal pleura and anteriorly by the costotransverse ligament
What is the goal of the paravertebral block?
inject LA alongside thoracic verebra close to where spinal nerves emerge from intervertebral foramen
What is the patient position for paravertebral block?
sitting (preferred), lateral or supine
How do you perform a paravertebral block?
patient is sitting and identify at desired levels and mark 2.5cm lateral to midline at the thoracic levels to be blocked- should lie over transverse process over the vertebra
Describe the paravertebral block with an US
Patient is in lateral decubitus position
high frequency linear array transducer placed in transverse orientation at the desired level lateral to spinous process
once hypoechoic transverse process and ribs are identified, slide transducer slightly caudad into the intercostal space
On US with a paravertebral block, what indicates correct spread of LA?
downward displacement of pleura
What are paravertebral block complications?
bilateral epidural anesthesia
pneumothorax
vascular puncture
hypotension (unilateral sympathetic block)
LAST
inadvertent epidural or spinal anesthesia
what are intercostal nerves?
nerves of the anterior chest and abdomen
nerves that innervate the ribs and come from the thoracic extension from ventral rami
What do intercostal nerves innervate?
t3-t9 provide motor supply to intercostal muscles and receive sensory information from skin and parietal pleura
What do lateral branches of the intercostal nerves innervate?
most of pectoral and axillary regions
Where is the long thoracic nerve located where and travels where?
axillary compartment close to lateral thoracic branch of the thoracoacrominal arteral
travels down lateral aspect of serratus anterior muscle to innervate it
What do the intercostal nerves pierce?
external intercostal muscle and exit between serratus anterior at level of midaxillary line
What are the indications for an intercostal nerve block?
analgesia following breast, thoracic and upper abdominal surgery, pain management of rib fractures
What does an intercostal nerve block target?
nerves resulting in ipsilateral anesthesia at specific levels
What is the intercostal nerves an extension of?
ventral rami of the thoracic nerve root
What occurs to the intercostal nerve at the midaxillary line?
nerve gives rise to lateral branch and terminates as anterior cutaneous branch
What is the position for an intercostal nerve block?
sitting, lateral decubitus, prone position with arms hanging freeky
Where is the US transducer placed for an intercostal nerve block?
sagittal plane over the costae approximately 6-8cm from midline
What are use identifying on US for an intercostal nerve block?
7 and 12th ribs to estimate position of relative ribs
Where is the needle inserted for an intercostal nerve block?
in plane until the tip is observed between the internal and innermost intercostal muscles
What landmark makes performing an intercostal nerve block difficult?
T7 scapula
What is a benefit of an intercostal nerve block?
good analgesia surgical anesthesia
Describe an interocostal nerve block procedure
20-22g 4-5cm needle
tuoy needle
palpate inferior border of ribs
insertion site approx. 7cm lateral to midline
insert needle at 20 degree cephalad angle with bevel facing cephalas
advance until needle contacts rib (less than 1 cm)
advance a few mm and may appreciate “pop” of fascia of intercostal muscle
Complications of an intercostal nerve block
abdominal viscera penetration hematoma penumothorax may occur in 1% peritoneum peneration LAST spinal anesthesia
What is the indication for a rectus sheath block?
umbilical surgery
How does the US aid in a rectus sheath block?
LA placement close to epigastric arteries and peritoneum
Where is the rectus abdominus?
oval shaped muscles below the superifical fascia of abdomen
What does the rectus sheath target?
intercostal nerves of T9-T11 located between rectus abdominis muscle and posterior fascia
small epigastric arteries in this area
peritoneum is deep to posterior fascia
What nerves innervate the abdomen?
T6-T12
What is the patient position for rectus abdominis block?
supine
Where is the transducer placed for an rectus sheath block?
high frequency transducer placed lateral to umbilicus in transverse orientation
How is the needle and LA injected in rectus sheath block?
inplane needle injection with up to 10ml LA injected bilaterally between rectus abdominis muscle and posterior fascial place
What are complications to the rectus sheath block?
peritoneum just below posterior fascia
epigastric artery injection
What is the pearl for rectus sheath block?
injections along lateral wall have been shown to be more efficacious
What does a TAP block stand for?
transversus abdominis plane block
When is a TAP block used?
alternative for low to mid- abdominal wall surgery when epidural and/or intrathecal opioids are CKA/refused
What does a TAP block depend on?
correct identification of transversus abdominis plane
dependent on interfascial spread
Where does a TAP block provide anesthesia?
abdominal wall from T7-L1
What is the patient position for a lateral TAP block?
supine
Describe the US technique for a lateral TAP block?
high frequency transducer placed between costal margin and iliac crest midaxillary line in transverse orientation
transducer slid medially and laterally until all three muscle layers are identified
in plane until tip penerates fascia between internal oblique and transversus abdominus
up to 20ml dilute LA per side
What are the three muscle layers to discover on US during a lateral TAP block?
external oblique muscle
internal oblique muscle
transversus abdominis muscle
What is the target for a lateral TAP block?
fascial plane between internal oblique and transversus abdominis muscles
Describe the posterior TAP block with US
linear transducers placed in axial plane in midaxillary line and moved posteriorly to the most posterior limit of TAP between internal oblique and transversus abdominis muscles
What is the target for posterior TAP block?
posterior end of TAP
Where do you insert your needle in a posterior TAP block?
needle in midaxillary line and advance posteriorly until it reaches posterior end of TAP
Describe a subcostal TAP block with US
linear transducer placed alongside lower margin of rib cage as medial and cranial as possible
identify rectus abdominis and transversus abdominus deep to posterior rectus sheath
Indications of a quadratus lumborum block
large bowel resection, appendectomy, cholecystectomy, cesearan section, total abdominal hysterectomy, prostatectomy, renal surgery, nephrectomy, abdominoplasty, iliac creast bone gradt, exploratory laparotomy
What does the quadratus lumborum block target?
iliohypogastric, ilioinguinal and subcostal nerves that cross the psoas muscle and transveralis fascia
What warrants caution in a quadratus lumborum block?
lower pole of kidney lies anterior to QL muscle
Describe the quadratus lumborum anatomy
QL muscle lies dorsolateral to psoas major in the posterior abdominal wall
QL originates from iliac crest and attaches to transverse processes of L1-L5 and 12th rib
How many types of quadratus lumborum blocks are there?
3
What does a QL1 block?
lateral cutaneous branches of iliohypogastric, ilioinguinal and subcostal nerves T12-L1
Describe the US technique of a QL1 block
linear transducer placed in an axial place in midaxillary line
move posteriorly until posterior aponeurosis of transversus abdominus muscle becomes visible
What is the target for a QL1 block?
just deep to aponeurosis but superficial to TF at lateral margin of QL muscle
Where are you injecting LA for a QL1 block?
LA goes between aponeurosis and the TF at the lateral margin of the QL
What is the target for QL2 block?
deep layer of the middle layer of TLF
Describe the QL2 US technique
linear transducer placed in axial plane in midaxillary line
move posteriorly as in QL1 until the LIFT (paraspinal muscles) become visible between latissimus dorsi and QL muscles
Where is the needle injected for a QL2 block?
needle inserted from lateral end and advanced until inside middle layer of TLF close to LIFT
What is the most common QL block?
QL3
Describe position and US technique of QL3
patient lateral decubitus with hips and knees flexed
curvilinear transducers placed midaxillary line cephalad to iliac crest
slide transducer posteriorly and tilt caudad until “shamrck sign” visualized
Describe the shamrock sign
L4 transverse process is stem
erector spinae posteriorly
QL laterally
psoas major anteriorly
What is the erector spinae block?
fascial plane block deep to spinae muscle group
sensory block with minimial hemodynamic effects
what does the erector spinae block target?
dorsal rami (potentially ventral rami)
Anatomy of the erector spinae block
erector spinae is group of muscles that provide support to spinal column
spinalis
longissimus
illiocastalis
What is the patient position for erector spinae block?
prone
Describe the erector spinae block technique
curvilinear transducers placed in parasagittal plane
identify optimal block level
volume dependent block
at desired level, slide transducer laterally to identify transverse process
insert needle cephalad to caudal
incremental injection of 5ml up to 20ml
repeat opposite side
For erector spinae blocks, how is the volume distribution determined?
four dermatomal level of distribution (two above and two below injection site
Complications of erector spinae blocks
block failure hematoma hemodynamic instability infection at site LAST lumbar plexus block pneumothorax tissue trauma
Pearls for erector spinae
unilateral block (mostly needs to be bilateral) volume dependent block: low concentration of LA allows for increased volume
