BCA Neuroanesthesia & Neurosurgical Procedures Flashcards

Which anesthetic agent is MOST commonly used for neurosurgical procedures due to its ability to decrease cerebral metabolic rate?

Answer: Propofol

Propofol reduces cerebral metabolic rate of oxygen (CMRO2) and decreases intracranial pressure, making it a preferred agent for neurosurgical procedures.

During craniotomy, a sudden bradycardia with hypertension (Cushing's triad) most likely indicates:

Answer: Raised intracranial pressure

Cushing's triad (hypertension, bradycardia, irregular respirations) is a classic sign of critically elevated intracranial pressure threatening brainstem herniation.

Which position is MOST associated with venous air embolism risk during neurosurgery?

Answer: Sitting (beach chair)

The sitting position places surgical sites above the heart level, creating negative venous pressure that dramatically increases the risk of venous air embolism.

The BEST method to detect venous air embolism intraoperatively is:

Answer: Precordial Doppler ultrasound

Precordial Doppler ultrasound is the most sensitive noninvasive monitor for detecting venous air embolism, able to detect as little as 0.05 mL of air.

Hyperventilation is used in neurosurgery primarily to:

Answer: Decrease PaCO2 to cause cerebral vasoconstriction

Hyperventilation lowers PaCO2, inducing cerebral vasoconstriction that reduces cerebral blood volume and intracranial pressure, creating better surgical conditions.

During spinal cord surgery, which electrophysiological monitoring modality assesses dorsal column (sensory) pathway integrity?

Answer: Somatosensory evoked potentials (SSEPs)

SSEPs monitor the dorsal column–medial lemniscal pathway (sensory), while MEPs assess the anterior corticospinal (motor) tracts.