ABA Regional & Neuraxial Anesthesia Flashcards

A post-dural puncture headache (PDPH) is BEST characterized by which feature?

Answer: Frontal/occipital pain worsened upright and relieved supine

PDPH is caused by CSF leak through the dural puncture site, causing traction on pain-sensitive intracranial structures when upright; lying flat relieves the traction.

The epidural blood patch is considered the DEFINITIVE treatment for PDPH. Its mechanism of action is:

Answer: Sealing the dural leak with a clot and transiently increasing epidural pressure

15–20 mL of autologous blood is injected epidurally; it clots over the dural tear and transiently increases epidural pressure, restoring normal CSF dynamics.

During spinal anesthesia, a 'total spinal' occurs. The MOST immediate life-threatening consequence is:

Answer: Apnea and cardiovascular collapse from high cervical blockade

High spinal block paralyzes intercostal and phrenic nerves and blocks cardiac accelerator fibers (T1-T4), causing apnea, bradycardia, and profound hypotension.

Which factor INCREASES the spread of spinal anesthesia?

Answer: Using hyperbaric solution in Trendelenburg position

Hyperbaric solutions are denser than CSF and flow with gravity; in Trendelenburg (head-down), hyperbaric local anesthetic migrates cephalad, increasing spread.

The recommended interspace for spinal anesthesia in adults to avoid spinal cord injury is:

Answer: L3-L4 or L4-L5

The spinal cord ends at L1-L2 in adults (conus medullaris); L3-L4 or L4-L5 interspaces are below the cord terminus, eliminating direct cord injury risk.

Local anesthetic systemic toxicity (LAST) involving the CNS typically presents in which ORDER?

Answer: Tinnitus/circumoral numbness → seizures → cardiovascular collapse

CNS excitation (tinnitus, perioral numbness, visual disturbance) precedes seizures, which precede CNS depression and eventual cardiovascular collapse as plasma levels rise.