Advanced | Regional Anesthesia (PNB)

Question 1

This nerve is often spared during an Interscalene brachial plexus nerve block?

A. Ulnar n.

B. Radial n.

C. Musculocutaneous n.

D. Median n.

Answer 1

A. Ulnar n.

ULNAR NERVE (SECOND Intercostal Brachial Nerve (medial aspect of upper arm)

Question 2

A 65-year-old woman has respiratory distress and loss of consciousness immediately following superficial and deep cervical plexus block for right carotid endarterectomy. Which of the following is the most likely cause?

(A) Phrenic nerve paralysis

(B) Pneumothorax

(C) Recurrent laryngeal nerve block

(D) Subarachnoid injection

(E) Vertebral artery injection

Answer 2

(D) Subarachnoid injection

Question 3

Following completion of an ankle block, the patient reports intact sensation on the tips of the toes. Which of the following nerves was blocked inadequately?

(A) Deep peroneal
(B) Posterior tibial
(C) Saphenous
(D) Superficial peroneal
(E) Sural

Answer 3

(B) Posterior tibial

Question 4

A patient has seizure activity 30 seconds after injection of 0.25% bupivacaine 2 ml with epinephrine 1:200,000 for stellate ganglion block. The most likely cause is:

(A) reaction to epinephrine in the anesthetic solution

(B) anaphylactoid reaction to bupivacaine

(C) subarachnoid injection of bupivacaine

(D) peridural venous injection of bupivacaine

(E) vertebral artery injection of bupivacaine

Answer 4

(E) vertebral artery injection of bupivacaine

Question 5

Nerve root of Musculocutaneous Nerve

Answer 5

C5 - C7

Question 6

The plasma concentration of equal doses of a local anesthetic is highest when the site of administration is

(A) axillary brachial plexus
(B) caudal
(C) intercostal
(D) lumbar epidural
(E) subcutaneous

Answer 6

(C) intercostal

Useful pnemonic:

It - IV > Tracheal
is
I - Intercostal
C - caudal
E - epidural
B - Brachial Plexus
a - Brachial Plexus
L - Lower ext.
S - Subcutaneous

Question 7

Nerve root of MEDIAN NERVE

Answer 7

C6 - T1

Question 8

Nerve root of ULNAR NERVE

Answer 8

C8 - T1

Question 9

This artery is the MOST commonly punctured artery during an brachial plexus nerve block?

A. Vertebral artery

B. Common carotid artery

C. Innominate artery

D. Jugular vein

Answer 9

Vertebral Artery

Question 10

Nerve root of Axillary nerve:

Answer 10

C5 - C6

Question 11

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

Answer 11

B. Sympathetic cervical block

Question 12

At what level of Brachial Plexus involves Interscalene block?

How many?

Answer 12

ROOTS (567)

3 ROOTS (C5, C6, and C7) Nerve roots

Question 13

What nerve root is spared in Interscalene block?

Answer 13

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.

Question 14

At what level of Brachial Plexus involves Supraclavicular block?

Answer 14

TRUNK

Question 15

Also considered as the SPINAL BLOCK of the arm?

Answer 15

Supraclavicular Nerve Plexus Block

Question 16

Why is supraclavicular plexus block not a good block for SHOULDER injury?

Answer 16

It misses the SUPRASCAPULAR NERVE

Question 17

When nerve stimulator is employed while doing PNB, twitching of which part of the upper extremity indicates an adequate block?

Answer 17

Twitching of the HAND/FINGERS

Question 18

The trunks form three anterior and three posterior divisions, which recombine and becomes:

Answer 18

3 CORDS at the Infraclavicular region

Question 19

CONTRAINDICATION of PNB:

Answer 19

1.Patient or Parent of a pediatric patient REFUSAL
2. Local infection
3. Systemic anticoagulation
4. Severe systemic coagulopathy

Question 20

To accentuate the SCM for Interscalene Block:

Answer 20

Ask the patient to reach for the ipsilateral knee and rotating the head approximately 45 degrees to the nonoperative side

Question 21

Interscalene groove is at what level of the cervical vertebrae?

Answer 21

C6

Question 22

While localizing the nerve for Interscalene block, a diaphragmatic response was elicited by the anesthesia resident? This means:

Answer 22

The PHRENIC nerve is being stimulated and that the needle is too ANTERIOR!

Question 23

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

Answer 23

A. CSF volume

Question 24

Block of each of the following nerves is required for inguinal herniorrhaphy EXCEPT:

(A) genitofemoral
(B) iliohypogastric
(C) ilioinguinal
(D) obturator
(E) twelfth thoracic

Answer 24

(D) obturator

Question 25

4. 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

Answer 25

C. Saphenous Nerve Saphenous nerve is a terminal branch of the femoral nerve

Question 26

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

Answer 26

A. Increased incidence of motor blockade

Question 27

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

Answer 27

A. Axillary nerve

Question 28

Transcutaneous electrical nerve stimulation is LEAST likely to be effective in which of the following pain syndromes? (A) Acute postoperative pain (B) Chronic pancreatitis (C) Myofascial syndrome (D) Phantom limb pain (E) Reflex sympathetic dystrophy

Answer 28

(B) Chronic pancreatitis * Celiac plexus block is indicated for the nociceptive pain coming from the celiac plexus which is the affected part in pancreatitis.

Question 29

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

Answer 29

C. Intercostal > caudal > epidural > brachial plexus > sciatic

Question 30

This block is indicated mostly for SURGICAL anesthesia of the shoulder and upper arm, and forearm but is often insufficient for the hand: A. Interscalene brachial plexus block B. Supraclavicular brachial plexus block C. Infraclavicular brachial plexus block D. Axillary nerve block

Answer 30

A. Interscalene brachial plexus block

Question 31

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

Answer 31

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.

Question 32

TRUE or FALSE An axillary block is not suitable for surgery of the upper arm

Answer 32

TRUE An axillary block is not suitable for surgery of the upper arm.

Question 33

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.

Answer 33

TRUE The block is performed by aligning an in-plane needle to a linear, HIGH-frequency probe.

Question 34

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.

Answer 34

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.

Question 35

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

Answer 35

TRUE Interscalene spares ULNAR border

Question 36

A supraclavicular block is performed at the level of distal trunks/proximal divisions.

Answer 36

TRUE

Question 37

An infraclavicular block is performed at the level of the CORDS.

Answer 37

TRUE

Question 38

This groove lies immediately behind the lateral border of the clavicular head of the sternocleidomastoid muscle at the level of the cricoid cartilage (C6).

Answer 38

INTERSCALENE GROOVE

Question 39

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.

Answer 39

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.

Question 40

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

Answer 40

HONEYCOMB structure is seen SUPERIOR and LATERAL to the subclavian artery = INTERSCALENE BRACHIAL PLEXUS

Question 41

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

Answer 41

INTERSCALENE BRACHIAL PLEXUS BLOCK

Question 42

while performing Interscalene brachial plexus block, you accidentally injected LA at the INTERVERTEBRAL FORAMEN. This will produce:

Answer 42

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.

Question 43

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

Answer 43

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.

Question 44

Which of the following is the most likely cause of apnea occurring after a retrobulbar block? (A) Epidural injection (B) Increased intracranial pressure (C) Oculopontine reflex (D) Ophthalmic artery injection (E) Subarachnoid injection

Answer 44

(E) Subarachnoid injection

Question 45

Horner syndrome is common in INTERSCALENE BRACHIAL PLEXUS BLOCK because:

Answer 45

spread to the sympathetic chain on the anterior vertebral body.

Question 46

“crampy” pain sensation produced during the FIRST INJECTION of LA while performing INTERSCALENE BLOCK

Answer 46

Neuropathy of the C6 root

Question 47

Which Rexed lamina layers in the gray matter of the spinal cord are involved in transmission of nociception?

Answer 47

125 I, II and V

Question 48

Which nerve can be spared by an infraclavicular block?

Answer 48

ULNAR NERVE

Question 49

Rectus sheath block target the terminal branches of which nerve?

Answer 49

9th, 10th, and 11th intercostal nerves within the rectus sheath!

Question 50

Ideally, where do we injection LA when doing a rectus sheath block ?

Answer 50

between POSTERIOR rectus sheath and the rectus abdominis muscle.

Question 51

TAP block is done by injecting a local anesthetic in which anatomical plane?

Answer 51

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

Question 52

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)

Answer 52

B. ESP (Erector Spinae)

Question 53

A successful ankle block for transmetatarsal amputation of the first and second toes should include each of the following nerves EXCEPT: (A) saphenous (B) deep peroneal (C) superficial peroneal (D) sural (E) tibial

Answer 53

(D) sural

Question 54

Diplopia following lumbar puncture with a 25-gauge, 3 1/2-inch needle is the result of (A) stretching the abducens nerve (B) pressure on the optic nerve (C) distortion of the oculomotor nucleus from collapse of the wall of the third ventricle (D) the severity of the accompanying headache (E) compensatory cerebral swelling

Answer 54

(B) pressure on the optic nerve