APPLIED ANATOMY | Part II Flashcards
Nerve that is frequently spared after Interscalene block?
A. Ulnar n.
B. Radial n.
C. Musculocutaneous n.
D. Median n.
A. Ulnar n.
ULNAR NERVE (SECOND Intercostal Brachial Nerve (medial aspect of upper arm)
Nerve root:
Nerve root of Axillary nerve:
C5 - C6
Nerve root of Musculocutaneous Nerve
C5 - C7
Nerve root of MEDIAN NERVE
C6 - T1
Nerve root of ULNAR NERVE
C8 - T1
Artery that can be accidentally punctured during Interscalene block:
Vertebral Artery
Horner syndrome as a complication of Interscalene nerve block is likely due to unintentional injury of which nerve?
A. Recurrent laryngeal nerve
B. Sympathetic cervical block
C. Inferior branch of laryngeal nerve
D. Phrenic Nerve
B. Sympathetic cervical block
At what level of Brachial Plexus involves Interscalene block?
How many?
ROOTS (567)
3 ROOTS (C5, C6, and C7) Nerve roots
What nerve root is spared in Interscalene block?
C8 and T1 roots (ULNAR distribution) are spared, hence it is not ideally done on HAND and FOREARM surgeries. * misses the INFERIOR ROOT that covers the ulnar nerve.
At what level of Brachial Plexus involves Supraclavicular block?
A. Division and Trunk
B. Cord
C. Roots
DIVISION and TRUNK
At what level of Brachial Plexus involves the blockade of Interscalene?
A. Division and Trunk
B. Cord
C. Roots
C. ROOTS
At what level of Brachial Plexus involves the blockade of Infraclavicular?
A. Division and Trunk
B. Cords
C. Roots
B. Cords
Also considered as the SPINAL BLOCK of the arm?
A. Supraclavicular brachial plexus block
B. Infraclavicular brachial plexus block
C. Interscalene brachial plexus block
Supraclavicular Brachial Plexus Block
Why is supraclavicular plexus block not a good block for SHOULDER injury?
It misses the SUPRASCAPULAR NERVE
When nerve stimulator is employed while doing PNB, twitching of which part of the upper extremity indicates an adequate block?
Twitching of the HAND/FINGERS
The trunks form three anterior and three posterior divisions, which recombine and becomes:
3 CORDS at the Infraclavicular region
CONTRAINDICATION of PNB:
1.Patient or Parent of a pediatric patient REFUSAL
2. Local infection
3. Systemic anticoagulation
4. Severe systemic coagulopathy
To accentuate the SCM for Interscalene Block:
Ask the patient to reach for the ipsilateral knee and rotating the head approximately 45 degrees to the nonoperative side
Interscalene groove is at what level of the cervical vertebrae?
A. C6
B. C7
C. C5
D. T1
C6
While localizing the nerve for Interscalene block, a diaphragmatic response was elicited by the anesthesia resident? This means:
The PHRENIC nerve is being stimulated and that the needle is too ANTERIOR!
What accounts for most of the variability in the spread and regression of neuraxial anesthesia?
A. CSF volume
B. pKa of Local Anesthetic
C. Lipid solubility
D. Nerve Myelination
A. CSF volume
- All of the following nerves at the ankle are terminal branches of the sciatic nerve EXCEPT:
A. Posterior tibial nerve
B. Sural nerve
C. Saphenous nerve
D. Deep peroneal nerve
E. Superficial peroneal nerve
C. Saphenous Nerve
Saphenous nerve is a terminal branch of the femoral nerve
Compared to opiate-only epidural infusion, use of a combination of local anesthetic and opioid epidural infusion leads to:
A. Increased incidence of motor blockade
B. Increased incidence of pruritus
C. Increased incidence of breakthrough pain
D. Decreased incidence of hypotension
E. Increased incidence of respiratory depression
A. Increased incidence of motor blockade
All of the following nerves can be blocked in the axilla
EXCEPT
A. Axillary nerve
B. Musculocutaneous nerve
C. Median nerve
D. Ulnar nerve
E. Intercostal brachial nerve
A. Axillary nerve
Which order of systemic local anesthetic toxicity is
correct?
A. Intercostal > caudal > epidural > sciatic > brachial plexus
B. Epidural > caudal > intercostal > brachial plexus > sciatic
C. Intercostal > caudal > epidural > brachial plexus > sciatic
D. Caudal > intercostal > brachial plexus > epidural > sciatic
E. Intercostal > caudal > epidural > sciatic > brachial plexus
C. Intercostal > caudal > epidural > brachial plexus > sciatic
This block is indicated mostly for SURGICAL anesthesia of the shoulder and upper arm, and forearm but is often insufficient for the hand:
INTERSCALENE
When performing an INTERSCALENE block with an ultrasound with an in-plane POSTERIOR approach, the needle
can be visualized going through which of the following
structures?
A. Middle scalene muscle
B. Anterior scalene muscle
C. Adjacent to the phrenic nerve
D. Sternocleidomastoid muscle
E. Adjacent to the internal jugular vein
A. Middle scalene muscle
In an ultrasound-guided posterior approach to the interscalene
block, the needle goes through the middle scalene muscle.
The trunks of the brachial plexus are located between the anterior and the middle scalene muscles. The anterior scalene muscle lies anterior to the trunks. The internal
jugular vein, the carotid artery, and the phrenic nerve are further anterior to the anterior scalene muscle. The sternocleidomastoid
muscle lies anterior and more superficial to the nerve trunks.
TRUE or FALSE
An axillary block is not suitable for surgery of the upper arm
TRUE
An axillary block is not suitable for surgery of the upper arm.
TRUE or FALSE
An interscalene block is performed at the level of the trunks and is the most proximal block of the brachial plexus, which is derived from C5–T1 nerve roots.
TRUE
The block is performed by aligning an in-plane needle to a linear, HIGH-frequency probe.
TRUE or FALSE
The intercostobrachial nerve innervates the LATERAL aspect of the upper arm and is derived from T2, and hence is not blocked with any brachial plexus block.
FALSE
The intercostobrachial nerve innervates the MEDIAL aspect of the upper arm not the lateral aspect. It is derived from T2, and hence is NOT BLOCKED with any brachial plexus block.
TRUE or FALSE
Interscalene block frequently spares the plexus’s lowest branches, the C8 and T1 fibers, which innervate the forearm’s caudad (ULNAR) border
TRUE
Interscalene spares ULNAR border
A supraclavicular block is performed at the level of distal trunks/proximal divisions.
TRUE
An infraclavicular block is performed at the level of the CORDS.
TRUE
This groove lies immediately behind the lateral border of the clavicular head of the sternocleidomastoid muscle at the level of the cricoid cartilage (C6).
INTERSCALENE GROOVE
TRUE or FALSE
When performing Interscalene Block using a nerve stimulator, A diaphragmatic or trapezius
twitches should be avoided, as they are associated with cervical plexus stimulation.
TRUE
Diaphragmatic or trapezius twitches should be avoided, as they are associated with cervical plexus
stimulation.
A diaphragmatic response indicates that the phrenic nerve is being stimulated and that the needle is too anterior.
Due to the compact arrangement of neck anatomy in children, an angled insertion may be needed (as opposed to perpendicular in adults) to avoid puncture of the VERTEBRAL artery or epidural/subarachnoid space.
At the supraclavicular fossa, the brachial plexus (trunks/divisions) can be seen in the short axis as a tightly enclosed cluster (i.e., honeycomb like), superior and lateral to the subclavian artery
HONEYCOMB structure is seen SUPERIOR and LATERAL to the subclavian artery = INTERSCALENE BRACHIAL PLEXUS
The plexus roots/trunks are typically seen as three or more round or ovalshaped hypoechoic structures sandwiched in the interscalene groove between the scalenus anterior and medius muscles
INTERSCALENE BRACHIAL PLEXUS BLOCK
while performing Interscalene brachial plexus block, you accidentally injected LA at the INTERVERTEBRAL FORAMEN. This will produce:
SPINAL or EPIDURAL ANESTHESIA
If the needle is allowed to pass directly medially, it may enter the intervertebral foramen, and injection of local anesthetic may produce spinal or epidural anesthesia.
The ________ passes posteriorly at the level of the sixth vertebra to lie in its canal in the transverse process that can be seen as a pulsatile structure deep to the
plexus
VERTEBRAL ARTERY
The vertebral artery passes posteriorly at the level of the sixth vertebra to lie in its canal in the transverse process that can be seen as a pulsatile structure deep to the plexus; direct injection into this vessel can rapidly produce central nervous system toxicity and convulsions.
Horner syndrome is common in INTERSCALENE BRACHIAL PLEXUS BLOCK because:
spread to the sympathetic chain on the anterior vertebral body.
“crampy” pain sensation produced during the FIRST INJECTION of LA while performing INTERSCALENE BLOCK
Neuropathy of the C6 root
Which Rexed lamina layers in the gray matter of the spinal cord are involved in transmission of nociception?
125
I, II and V
Which nerve can be spared by an infraclavicular block?
ULNAR NERVE
Rectus sheath block target the terminal branches of which nerve?
9th, 10th, and 11th intercostal nerves within the rectus sheath!
Ideally, where do we injection LA when doing a rectus sheath block ?
between POSTERIOR rectus sheath and the rectus abdominis muscle.
TAP block is done by injecting a local anesthetic in which anatomical plane?
between the TRANSVERSUS abdominis and INTERNAL oblique muscles.
The TAP block aims to impede innervation of the abdominal wall UP to the level of T8 by injecting local anesthetic between the transversus abdominis and internal oblique
muscles
This fascial plane runs from T1 and the cervical vertebrae to the medial sacral crest on both sides of the spine. It is believed that its analgesic mechanism involves blocking the DORSAL and VENTRAL rami of the spinal nerves and sympathetic fibers, with diffusion and spreading both cranially and caudally to encompass numerous vertebral levels:
A. Paravertebral space
B. ESP (Erector Spinae)
C. QL plane
D. SAP (Serratus AnteriorPlane)
B. ESP (Erector Spinae)
Which of the following is DEVOID of motor innervation?
A. Femoral n.
B. Obturator n.
C. Lateral femoral cutaneous n.
D. Sciatic n.
C. Lateral femoral cutaneous n.
Injury to which of the following nerves would MOST likely result in numbness and paresthesias along the medial lower leg?
A) Deep branch of the common peroneal nerve
B) Saphenous nerve
C) Superficial branch of the common
peroneal nerve
D) Tibial nerve
Injury to a saphenous nerve can cause numbness, pain, and/or paresthesias along the medial lower leg.
The saphenous nerve is a major sensory branch of the femoral nerve that is primarily responsible for cutaneous sensation of the medial lower leg (see figure below).
Perioperative saphenous nerve injury is relatively uncommon but, due to its close proximity to the great saphenous vein, is a known complication of saphenous vein harvest (e.g., vein graft harvest for coronary artery bypass grafting) or saphenous vein stripping. Rarely, saphenous nerve block can also cause temporary or permanent nerve injury. Damage to the saphenous nerve may result in temporary or permanent cutaneous sensory loss, pain, or paresthesias.
In this cross-sectional diagram of an upper arm during an axillary block, which of the following are the correct anatomical structures represented by #1 and #2?
A. #1) Musculocutaneous nerve #2) Ulnar nerve
B. #1) Musculocutaneous nerve #2) Median nerve
C. #1) Musculocutaneous nerve #2) Radial nerve
C. #1) Musculocutaneous nerve #2) Radial nerve
When performing an axillary brachial plexus block, three of the four major nerve branches to the arm are contained within the axillary sheath and surround the axillary artery. The radial nerve is the most posterior and is closest to the humerus and is commonly described as being in the six o’clock position relative to the artery when viewed on ultrasound. The median nerve is anterolateral to the artery and is often found in the nine or ten o’clock position. The ulnar nerve is anteromedial to the artery and typically located in the three o’clock position.
The nerve that is not present in direct proximity around the axillary artery is the musculocutaneous nerve and is commonly not blocked with the axillary technique. The musculocutaneous nerve is blocked by injection through the coracobrachialis muscle after traveling ventral to the humerus.
