BCA Regional Anesthesia Techniques 2 — Questions and Answers
Question 1: Which landmark is used to identify the correct interspace for a lumbar epidural in an obese patient when ultrasound is unavailable?
- Iliac crest at L4-L5 (Correct answer)
- Inferior angle of scapula at T7
- Spinous process of C7
- Posterior superior iliac spine at L5-S1
Correct answer: Iliac crest at L4-L5
The iliac crest typically crosses the L4-L5 interspace and serves as the primary surface landmark for lumbar epidural placement.
Question 2: A patient develops sudden dyspnea and decreased breath sounds on the right after a right-sided interscalene nerve block. What is the most likely complication?
- Pneumothorax (Correct answer)
- Phrenic nerve palsy
- Horner syndrome
- Recurrent laryngeal nerve block
Correct answer: Pneumothorax
Pneumothorax is a recognized complication of interscalene block due to the proximity of the lung apex, presenting with dyspnea and unilateral absent breath sounds.
Question 3: When performing a transversus abdominis plane (TAP) block, the local anesthetic is deposited in which fascial plane?
- Between the internal oblique and transversus abdominis muscles (Correct answer)
- Between the external and internal oblique muscles
- Deep to the transversus abdominis muscle
- Subcutaneous layer above the external oblique
Correct answer: Between the internal oblique and transversus abdominis muscles
The TAP block targets the neurovascular plane between the internal oblique and transversus abdominis muscles where the T10-L1 nerves travel.
Question 4: Which of the following is the MOST appropriate management of a tourniquet pain that occurs 45 minutes into surgery under IV regional anesthesia (Bier block)?
- Deflate the distal cuff and inflate the proximal cuff
- Inflate the proximal cuff and deflate the distal cuff (Correct answer)
- Add supplemental IV opioids and continue
- Immediately deflate both cuffs
Correct answer: Inflate the proximal cuff and deflate the distal cuff
For Bier block tourniquet pain, inflating the proximal cuff (over anesthetized skin) and then deflating the distal cuff reduces pain while maintaining safety.
Question 5: What is the maximum safe volume of 0.25% bupivacaine for an ultrasound-guided femoral nerve block in a 70 kg adult?
- 20-30 mL (Correct answer)
- 5 mL
- 50 mL
- 60 mL
Correct answer: 20-30 mL
For peripheral nerve blocks, 20-30 mL of 0.25% bupivacaine provides adequate spread while remaining well within the maximum dose of 2.5 mg/kg (175 mg for 70 kg).
Question 6: A patient with a history of anticoagulation on therapeutic warfarin (INR 2.4) requires neuraxial anesthesia. What is the MOST appropriate action?
- Postpone neuraxial block until INR is ≤1.5 (Correct answer)
- Proceed with epidural if INR < 3.0
- Reverse with vitamin K and proceed immediately
- Perform spinal anesthesia only, not epidural
Correct answer: Postpone neuraxial block until INR is ≤1.5
ASRA guidelines recommend an INR ≤1.4 before neuraxial procedures to minimize epidural hematoma risk in anticoagulated patients.
Question 7: During a popliteal sciatic nerve block, which two nerves are targeted?
- Common peroneal and tibial nerves (Correct answer)
- Femoral and obturator nerves
- Sural and saphenous nerves
- Lateral femoral cutaneous and femoral nerves
Correct answer: Common peroneal and tibial nerves
The sciatic nerve divides into the common peroneal and tibial nerves at the popliteal fossa, and both are targeted in a popliteal sciatic block.
BCA Regional Anesthesia Techniques 2
Which landmark is used to identify the correct interspace for a lumbar epidural in an obese patient when ultrasound is unavailable?