and you observe supination of the forearm. The needle tip is closest to which of the
following brachial plexus nerve branches?
16. After performing an axillary peripheral nerve block, your ultrasound probe moves to
scan laterally and you see what appears to be an oval and hyperechoic nerve
structure within the belly of the coracobrachialis muscle. When the needle tip is
advanced closer to this structure and the nerve stimulator is activated, you notice
that the elbow begins to flex. The most likely nerve branch that is being stimulated is
17. You successfully perform a right supraclavicular nerve block for a right wrist open
reduction interior fixation. You are called to the post–anesthesia care unit 2 hours
later because the patient is complaining of pain on the back of the wrist, which
extends distal to the index, middle, and ring fingers on the dorsal surface of the hand.
You consent the patient to perform a terminal branch nerve block to supplement the
initial block. The nerve that would be needed to be blocked is
18. You have just successfully performed a Bier block using 50 mL 0.5% lidocaine for
carpal tunnel release surgery in a 45-year-old male (height, 6 ft; weight, 200 lb). The
patient was sedated with 2 mg of midazolam upon arrival to the OR. Ten minutes
following the local anesthetic placement, the surgeon indicates that the surgery is
finished. At the surgeon’s request, the nurse releases the tourniquet that was placed
on the upper arm. The patient soon becomes agitated, and you notice twitching of the
patient’s arms and legs. The most likely diagnosis is
C. Allergic reaction to the local anesthetic
D. Local anesthetic systemic toxicity (LAST)
19. A properly performed lumbar plexus block will result in blockade of all the
following nerve branches, except
B. Lateral femoral cutaneous nerve
20. Electrical nerve stimulation of which of the following nerves will produce
quadriceps muscle contraction?
C. Lateral femoral cutaneous nerve
21. You have just performed a femoral nerve block in preparation for a tibial plateau
fracture repair using 20 mL 0.5% ropivacaine. Three hours postsurgery in the
recovery room, the patient complains of lateral thigh pain. Was the femoral nerve
block a failure and what would be the most appropriate action?
A. Yes, repeat the femoral nerve block due to a failed block
B. No, repeat the femoral nerve block as the effectiveness of the local anesthetic
C. No, the pain expressed is not located within the distribution of the femoral
nerve, supplement with a lateral femoral cutaneous nerve block
D. Yes, the pain is due to a failed femoral block, but do not repeat the block as
there exists a high risk of nerve injury
22. A properly placed psoas compartment block or posterior lumbar plexus block can
be associated with any of the following complications, except
C. Local anesthetic systemic toxicity
23. You are consulted on an ASA IV patient for a right-ankle surgery. The patient has a
known history of difficult intubation and status post–spinal fusion surgery. The
surgeon is requesting for a peripheral nerve block that will provide for surgical
anesthesia. Which of the following nerves will need to be blocked in order to provide
for complete anesthesia during performance of foot and ankle surgery?
A. Both sciatic and femoral nerve blockade
D. Sciatic, femoral, and obturator nerve blocks
24. All of the following nerves provide sensory innervation to the foot, except
A. Lateral femoral cutaneous nerve
25. The most correct statement concerning a unilateral paravertebral block is
A. Such a block is always associated with a similar degree of sympathectomy as
B. Such a block is often associated with a higher serum level of local anesthetic
than that achieved with an intercostal nerve block due to high vascularity
C. It is not likely to be associated with a pneumothorax
D. Such a block may be associated with epidural spread of local anesthetic
26. The most incorrect statement regarding transversus abdominis plane (TAP) block is
A. TAP blocks can provide analgesia following hernia repair surgeries
B. TAP blocks can often alleviate both somatic and visceral pain
C. One potential complication includes liver injury
D. Unilateral TAP blocks never cross over the midline
27. When performing a transversus abdominis plane (TAP) block, the goal is to
deposit/inject local anesthetic between which of the following two muscle layers?
A. External oblique and internal oblique muscles
B. Internal oblique and transversus abdominis muscles
C. Transversus abdominis and external oblique muscles
D. Rectus abdominis and external oblique muscles
28. While performing the popliteal approach for a sciatic nerve block under ultrasound
guidance, you are able to identify the popliteal artery adjacent to two hyperechoic
nerve structures that appear to become one nerve structure upon proximal movement
of the ultrasound probe placed within the popliteal fossa. The correct identity of the
A. The nerve on the lateral side is the common peroneal nerve, and the nerve on
the medial side is the tibial nerve (combined nerve is the sciatic nerve)
B. The nerve on the lateral side is the sciatic nerve, and nerve on the medial side is
the deep peroneal nerve (combined nerve is the femoral nerve)
C. The nerve on the lateral side is the common tibial nerve, and nerve on the
medial is the superficial peroneal nerve (combined nerve is the sciatic nerve)
D. The nerve on the lateral side is the common posterior tibial nerve, and the nerve
on the medial side is the superficial peroneal nerve (combined nerve is the
29. The most appropriate statement regarding the function of the saphenous nerve is
A. It serves as both a motor nerve and a sensory nerve
B. It is the motor terminal branch of the femoral nerve
C. It is the sensory terminal branch of the femoral nerve
D. It is a sensory terminal branch of the sciatic nerve
30. An interscalene block will typically deposit the local anesthetic between which of
A. Anterior and middle scalene muscles
B. Middle and posterior scalene muscles
C. Anterior and posterior scalene muscles
D. Sternocleidomastoid and anterior scalene muscles
31. A 45-year-old healthy male is scheduled for bilateral elbow open reduction interior
fixation secondary to a motor vehicle accident. Successful bilateral supraclavicular
blocks were planned and performed under ultrasound guidance, with 20 mL 0.5%
ropivacaine injected for each block on each side. In the operating room, the patient is
receiving 25 μg/kg/min of a propofol infusion and oxygen via a non-rebreather bag.
The patient also received 2 mg of midazolam, but no opioids. Thirty minutes after
incision, the patient is experiencing progressive respiratory depression, and the
oxygen saturation decreases from 100% to 85%. The most likely diagnosis is
A. Local anesthetic systemic toxicity (LAST)
B. Dysfunction of the diaphragm (diaphragm palsy)
32. The most appropriate treatment for the patient in the above scenario is
A. Methylene blue due to local anesthetic systemic toxicity
B. Flumazenil to antagonize midazolam (oversedation)
C. Endotracheal intubation to provide respiratory support
D. Antibiotics to treat aspiration pneumonia
33. A 56-year-old woman is scheduled for a right total knee replacement. She has a
medical history of hypertension, diabetes mellitus, obesity, and is status post L1–L5
vertebral fusion. The regional anesthetic technique that will provide her the most
optimal perioperative pain management is
A. A femoral nerve block and an epidural
B. A femoral and proximal sciatic nerve block
C. Both a femoral and popliteal sciatic nerve block
D. A sciatic nerve block and a spinal
34. A 65-year-old female is scheduled for a right total shoulder replacement. Under
ultrasound guidance, you perform a right interscalene nerve block and place a
catheter for continuous local anesthetic infiltration planned for 3 days. One week
later, the patient complains of persistent parasthesia of the entire right arm, including
the wrist, hand, and all fingers (from the shoulder to the fingers). An MRI shows a
diffuse swelling of the brachial plexus at the level of the cords. The most likely
A. Direct nerve injury/trauma from the block needle used
B. Irritation of the brachial plexus at the level of the branches from the continuous
C. Surgical trauma/manipulation of the brachial plexus at the level of the cords
D. Local anesthetic toxicity of the brachial plexus at the level of the roots/trunks
35. The foot is supplied mainly by which of the following nerve(s)?
B. Obturator and tibial nerves
C. Femoral and lateral femoral cutaneous nerves
D. Saphenous and common peroneal nerves
36. The following local anesthetic medication is associated with the highest risk for
cardiovascular collapse in the event of local anesthetic systemic toxicity (LAST)
37. The most appropriate nerve block for pain management in a patient scheduled for a
C. Femoral and obturator nerve block
D. Femoral and lateral femoral cutaneous nerve block
38. The femoral nerve provides sensory innervation to the
A. Lower extremity below the knee
39. Sciatic nerve blockade provides sensory loss of the
B. Posterior thigh and majority of the leg below the knee
40. You perform a right-side T3–T5 paravertebral blockade for a patient who is to
undergo a right mastectomy with axillary lymph node dissection. Medical history of
the patient includes alcohol abuse and panic attacks. After the surgery in the post–
anesthesia care unit, the patient complains of a new-onset right-arm paresthesia. Vital
signs remain stable along with strong and equal upper extremity bilateral pulses. The
A. Surgery-related brachial plexus nerve injury and/or positional injury
B. The patient is experiencing withdrawal from alcohol
C. Side effects/complications of the paravertebral block on the brachial plexus
D. Patient is having a panic attack
41. You successfully perform and place a bilateral T8 continuous paravertebral block
catheters for an open–partial hepatectomy. Eighteen hours postoperatively, the
patient complains of 7/10 pain. To improve postoperative analgesia, 10 mL of 0.2%
ropivacaine is administered through each catheter. Twenty minutes later, the patient
indicates that the pain has decreased to 4/10. The most likely aspect of paravertebral
blockade that can account for the reason why the patient did not achieve a pain-free
A. The block level was too high; it should have been placed at the T10 level
B. The block level is too low; it should have been placed at the T6 level
C. Paravertebral blockade analgesia provides for mostly somatic blockade and
does not provide for complete coverage of visceral pain
D. The local anesthetic volume administered is too small
42. A patient is to undergo surgery to create an arteriovenous fistula for hemodialysis on
the antecubital area of the right upper extremity. You perform a right supraclavicular
block uneventfully using 20 mL 0.5% ropivacaine. The patient has a medical history
significant for hypertension and end-stage renal disease. Three days following the
surgery, the patient complains that she has no sensation from the right elbow to the
tips of all her fingers, but she can move all of her fingers normally. The most likely
A. Neurotoxicity of the trunks/divisions of the brachial plexus secondary to the
B. Nerve injury secondary to the regional block needle used
C. Prolonged effect of the local anesthetic secondary to the patient’s renal failure
D. Possible surgery-related injury at the elbow that may warrant an
43. While performing an axillary brachial plexus blockade, the goal is to deposit local
anesthetic medications at what location of the brachial plexus and to target which
A. Level of the branches and targeting the radial, median, and ulnar peripheral
B. Level of the trunks and targeting the interscalene, radial, and ulnar peripheral
C. Level of the divisions and targeting the supraclavicular, median, and radial
D. Level of the cords and targeting the infraclavicular, ulnar, and radial peripheral
44. Which of the following approaches to blockade of the brachial plexus is associated
with the highest incidence of a pneumothorax?
A. Interscalene and axillary approaches
B. Supraclavicular and interscalene approaches
C. Infraclavicular and axillary approaches
D. Axillary and interscalene approaches
45. All of the following medication adjuvants can be used in combination with local
anesthetic solutions during performance of a peripheral nerve blockade to extend the
duration/effectiveness of nerve blockade, except
46. While performing a femoral nerve block guided with a nerve stimulator, you observe
a strong sartorius muscle twitch that disappears at 0.2 mA. What does this mean and
how should you proceed further?
A. The stimulating block needle tip is in the correct position, and the local
B. The needle tip is likely superficial to the femoral nerve, and the block needle
needs to be readjusted (twitch may not be from stimulation of the femoral nerve)
prior to local anesthetic injection
C. Sartorius muscle twitch indicates that the needle tip is in the correct location,
but you need to get closer to the nerve as 0.2 mA stimulus is too high
D. The block needle needs to be repositioned more medially, and a paresthesia
must be elicited prior to local anesthetic injection
47. The trauma team in the ICU did not want a thoracic epidural placed on a trauma
patient with bilateral rib fractures secondary to concerns about the potential
hemodynamic instability that may result. Therefore, both right T7 and left T5
continuous paravertebral catheters were successfully placed for this patient under
ultrasound guidance. Twenty minutes following the administration of 10 mL of 0.2%
ropivacaine administered through each catheter (following evidence of negative
aspiration), the systolic blood pressure dropped by 50 mm Hg. The most likely
A. Performance of paravertebral blockade creates identical concerns about
potential hemodynamic compromise as do thoracic epidural blocks
B. Local anesthetic toxicity as the paravertebral space is very vascular
C. Possible epidural spread of local anesthetics from either one or both the
D. Venous bleeding into the paravertebral space resulting in large volumes of local
anesthetic absorption from the paravertebral blocks
1. C. In a patient with severe pulmonary compromise, performing either an
interscalene or supraclavicular block of the brachial plexus should be approached
with caution secondary to the increased risk of an ipsilateral phrenic nerve palsy.
Placement of an interscalene block for wrist surgery may also not be optimal as it
may not effectively block the ulnar nerve distribution to the wrist. A superficial
cervical plexus block (C1–C4) will not effectively provide anesthesia/analgesia to
the wrist. Both infraclavicular and axillary approaches to the brachial plexus would
be appropriate for wrist surgery, along with a reduced incidence of adverse effects on
the phrenic nerve. Intercostobrachial nerve blockade is added to cover the T2
dermatome distribution that is not included in a properly performed brachial plexus
block and will contribute to alleviating tourniquet discomfort in the medial portion of
2. B. The musculocutaneous and medial brachial cutaneous nerves branch from the
brachial plexus at a more proximal location than can be consistently anesthetized
with an axillary nerve block approach of the brachial plexus. Therefore, these nerve
branches need to be blocked separately if they innervate the planned surgical area.
The lateral brachial cutaneous nerve is a branch of musculocutaneous nerve.
3. A. Patient refusal is an absolute contraindication following informed consent.
Evidence of anticipated injection-site infection and severe coagulopathy are
considered relative contraindications, and risk-to-benefit analysis needs to be
carefully considered. Non-cooperative patients can often pose an increased risk to
patient/operator safety, but it is not an absolute contraindication to performing
4. D. Regional anesthesia should be administered in a monitored location where
standard ASA monitors. Supplemental oxygen along with resuscitative medications
and equipment should be readily accessible and immediately available. However,
immediate access to a functioning anesthesia ventilator is not always necessary.
5. B. High-frequency ultrasound probes are typically manufactured with a liner probe
design and provide high image resolution used for superficial anatomical structures.
Low-frequency ultrasound probe equipment is typically produced with a curvilinear
probe design and reveals a lower image resolution, but is used for visualizing deeper
anatomical structures secondary to better penetration.
6. D. The ulnar nerve branch originates from the C8–T1 nerve roots. Properly
performed interscalene approach to brachial plexus blockade can provide for a dense
blockade of the C5–C7 nerve roots/trunks and less consistent blockade of the C8–T1
nerve roots/trunks. Therefore, an interscalene approach to blockade of the brachial
plexus for distal upper extremity surgical procedures may not be the most ideal
7. C. A Horner syndrome (miosis, ptosis, and anhidrosis) can be commonly seen
following an interscalene block. This syndrome is often due to proximal tracking of
local anesthetic and blockade of the sympathetic fibers to the cervicothoracic
ganglion. In patients where a CVA may also be within the differential diagnosis, a
thorough history and neural exam should always be included.
8. B. A supraclavicular approach to brachial plexus blockade does not consistently
and reliably provide anesthesia/analgesia to the axillary and suprascapular nerve
branches. Therefore, a supraclavicular block can be used for postoperative analgesia,
but may not be ideal for surgical anesthesia during invasive shoulder procedures.
Sparing of ulnar nerve during a supraclavicular block may also occur that would not
provide effective anesthesia for procedures distal to the mid-humerus.
9. C. At the infraclavicular level, the brachial plexus forms three cords in relation to
axillary artery and named according to their position around the artery: medial,
10. B. Supraclavicular blockade of the brachial plexus is often referred to as the
“spinal anesthesia” of the upper extremity. It provides anesthesia of the brachial
plexus distal to the roots and proximal to the cords of the plexus. There has been an
increased practice of performing the supraclavicular approach to blockade of the
brachial plexus secondary to the introduction of ultrasound into clinical practice as
anesthesiologists can now appreciate a decreased incidence of pneumothorax under
real-time ultrasound guidance.
11. C. The musculocutaneous nerve typically branches off more proximal to the
axillary approach of brachial plexus blockade and is frequently not adequately
anesthetized with a traditional axillary block of the plexus (local anesthetics are
deposited around the axillary artery). Therefore, the musculocutaneous nerve must
be targeted separately when performing an axillary block of the brachial plexus for
distal upper extremity surgery.
12. C. Although some anatomical variation can be found with the brachial plexus at
the level of the axilla, the musculocutaneous nerve is most commonly positioned
within the coracobrachialis muscle or between the bellies of the biceps and
13. B. Some anatomical variation can exist, but the ulnar nerve is frequently
positioned inferior to the axillary artery. Stimulation of the ulnar nerve will cause
wrist flexion, flexion of the fourth and fifth digits, and thumb adduction.
14. A. The median nerve is most frequently positioned superior to the axillary artery
(with some anatomical variations). Stimulation of the median nerve will cause muscle
stimulation, creating wrist flexion, thumb opposition, and forearm pronation.
15. D. Despite some anatomical variations within the nerve-branch distribution of the
brachial plexus around the axillary artery, the radial nerve is most frequently
positioned posterior to axillary artery. Stimulator of radial nerve will induce
digit/wrist/elbow extension and forearm supination.
16. C. Musculocutaneous nerve is frequently found within coracobrachialis muscle
and/or between the biceps and coracobrachialis muscles. Stimulation of the
musculocutaneous nerve will characteristically cause elbow flexion.
17. B. The sensory distribution on the dorsal surface of the hand described in the
question matches the innervation provided by the radial nerve. Therefore, a terminal
nerve block anywhere along the distribution of the radial nerve proximal to the wrist
would be an appropriate place to supplement the initial brachial plexus block.
18. D. LAST can occur when a large volume of local anesthetic is absorbed into or
directly injected into the systemic circulation. A Bier block can provide surgical
anesthesia for short procedures of the extremity, lasting 60 minutes or less. However,
patients may complain of tourniquet pain that can become evident as early as 20
minutes following block performance. In order to prevent or reduce the incidence of
LAST, the tourniquet needs to remain inflated and in position for a minimum of 15 to
20 minutes even if the surgical procedure finishes early. Even after 15 to 20 minutes
has elapsed, cautious, intermittent, and slow release of tourniquet is recommended.
19. D. The three major nerve branches of the lumbar plexus that are affected by such
a block include femoral, lateral femoral cutaneous, and obturator nerves. Sciatic
nerve originates from the sacral plexus and is not part of the lumber plexus.
20. A. The femoral nerve provides motor supply to the quadriceps muscles and
sensory supply to portion of the medial thigh. The femoral nerve does not have any
motor components below the knee (only a sensory branch, saphenous nerve, below
21. C. The lateral femoral cutaneous nerve supplies the lateral portion of the thigh.
Blockade of the lateral femoral cutaneous nerve is not always consistently blocked
with femoral nerve block approach, but can be blocked separately if/when needed.
22. D. A lumbar plexus block is considered a deep block and has been described as
an advanced block in regional anesthesia. Some potential complications include
retroperitoneal hematoma, local anesthetic systemic toxicity, intrathecal and/or
epidural injections of local anesthetics, and renal injury (with potential for
subsequent hematoma). The typical approach for lumbar plexus blockade should not
cause injury to the sciatic nerve unless an improperly placed or misdirected regional
block needle is positioned too caudad that could then result in injury to sacral plexus
23. A. For complete surgical anesthesia of the foot and ankle, both sciatic and
femoral/saphenous nerves need to be anesthetized/blocked. The obturator nerve does
not provide sensory or motor nerve distribution to foot or ankle.
24. A. An ankle block can be performed by providing anesthesia and blocking the five
nerves that innervate the foot, namely, the superficial and deep peroneal nerve,
saphenous nerve, sural nerve, and posterior tibial nerve.
25. D. Advantages of properly placed paravertebral nerve blocks include reduced
degrees of local anesthetic–induced sympathectomy compared to epidural or spinal
anesthesia and a lower risk of local anesthetic systemic toxicity as compared with
intercostal nerve blocks. However, one of the major concerns for potential
complications is development of a pneumothorax, and paravertebral blocks can be
associated with variable degrees of local anesthetic epidural spread, especially when
placing bilateral paravertebral blocks.
26. B. TAP blocks can provide analgesia for peripheral somatic pain of the abdomen
and can be associated with a low yet potential risk of bowel perforation and liver
injury. For midline ventral hernia surgery, performing bilateral TAP blocks are often
needed. TAP blocks do not cover crappy, visceral pain.
27. B. The subcostal (T12), ilioinguinal (L1), and iliohypogastric (L1), and
genitofemoral nerves are targeted when performing a TAP block. These nerves have
a typical distribution between the internal oblique and transversus abdominis
28. A. Popliteal approach to the sciatic nerve block is typically performed at the site
of bifurcation of the tibial (medial position) and common peroneal (lateral position)
nerves. The sciatic nerve is most optimally blocked with local anesthetic at the union
(bifurcation) of these two nerves that frequently become one nerve structure
approximately 7 to 10 cm proximal to the popliteal crease.
29. C. The saphenous nerve is a terminal sensory nerve branch of the femoral nerve
with NO motor components. Under certain clinical situations, the saphenous nerve is
preferentially blocked to avoid motor blockade of the anterior quad muscles that can
result from performance of a femoral nerve block (increased risk of fall).
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