Actual Complete Exam |Already Graded A+
If you have high frequency noise in a BAEP:
A100/100 pts
Change HFF from 3000 to 1500 Hz
Change HFF to 200 Hz
Change LFF to 150 Hz
Change LFF to 30 Hz ✔Correct Answer-Change HFF from 3000 to 1500 Hz
To dissect a vestibular schwannoma, which surgical approach usually sacrifices hearing?
suboccipital
retrosigmoid
middle cranial fossa
translabyrinthine ✔Correct Answer-translabyrinthine
According to current OSHA standards, needle electrodes should
be reused whenever possible
not be soaked in a sodium hypochlorite solution
be recapped before discarding
not be handled with tongs or forceps while cleaning ✔Correct Answer-not be soaked in a
sodium hypochlorite solution
PTN (above) and MN SSEPs (below) are shown. Which of the following is the most likely cause of
the changes relative to baseline (blue traces)?
Anesthesia is too deep
Insufficient blood flow to the left leg
Left spinal cord injury
Brachial plexus compression ✔Correct Answer-Left spinal cord injury
Movement artifact on the EEG is most likely to produce
slow EEG wave activity
fast EEG wave activity
asymmetrical activity at 60 Hz
burst-suppression ✔Correct Answer-slow EEG wave activity
The main advantage of asynchronous bilateral stimulation is?
,Faster data acquisition
Differentiation of local vs. systemic effects
Reduction of stimulus artifact
Less patient movement ✔Correct Answer-Differentiation of local vs. systemic effects
Increases in latency of both right and left ABR wave V of 0.9 msec. in a 10 minute period would
most likely indicate
auditory nerve damage
ambient noise
temperature effects
a kink in the sound delivery tubing ✔Correct Answer-temperature effects
Which of the following can increase SEP amplitudes?
etomidate
fentanyl
isoflurane
1/2 MAC of halothane ✔Correct Answer-etomidate
Which of the following neurotransmitters always causes excitation of postsynaptic neurons?
gamma amino butyric acid
glycine
dopamine
glutamate ✔Correct Answer-glutamate
The motor cervical spine C5 nerve root produces:
Arm abduction
Elbow extension
wrist extension
wrist flexion ✔Correct Answer-Arm abduction
During a spinal instrumentation for scoliosis the surgeon reports that derotation is now being
performed. Which of the following is the most appropriate statement?
The event should be documented immediately
Documentation of this event is not important
Documentation of the event should be performed at the end of the surgery after monitoring
has been completed
This is a good time to take a break from monitoring since there is very little risk to the spinal
cord at this time ✔Correct Answer-The event should be documented immediately
,During BAEP for posterior fossa craniotomy, if reversible loss of all ipsi BAEP responses occurs:
probable neuronal deficit postop
complete recovery of neuronal function
hypothermia
drug effect ✔Correct Answer-complete recovery of neuronal function
For patients showing clamp-related EEG changes during carotid endarterectomy, 80% of the
changes appear within the
first 10 seconds
first 60 seconds
frontal leads only
alpha frequency range ✔Correct Answer-first 60 seconds
An advantage of referential, as opposed to bipolar recording of spinal cord somatosensory
evoked potentials, is
the ease of electrode placement
less invasion of the surgical field
the elimination of electromyographic artifact from the paraspinous muscles
avoiding cancellation of the potentials as a result of recording from adjacent levels ✔Correct
Answer-avoiding cancellation of the potentials as a result of recording from adjacent levels
An electrode measured 20% lateral to Cz on the right using 10-20 system is
C4
A2
T3
C3 ✔Correct Answer-C4
Waves III to V on the ABR are probably generated
at the cortex
at the cerebellum
at the medulla
at the pons-midbrain area ✔Correct Answer-at the pons-midbrain area
An agent that should be avoided immediately before EMG for facial nerve monitoring is
N20
vecuronium
phenytoin
isoflurane ✔Correct Answer-vecuronium
, A unit of resistance is symbolized by
A
μ
Ω
E ✔Correct Answer-Ω
The effects of halogenated agents on the cortical somatosensory evoked potential are
an increase in latencies and an increase in amplitudes
minimal compared with the effects on BAEPs
negligible
an increase in latencies and a decrease in amplitudes ✔Correct Answer-an increase in
latencies and a decrease in amplitudes
When recording BAEPs in the OR, some auditory stimulators utilize several inches of tubing to
connect the transducer and ear inserts which
do not affect the latencies of the waveforms
are comparable to acoustically shielded headphones
delay the signal to the transducer and can cause 60 Hz artifact
delays the arrival of the sound to the ear and separates stimulus artifact ✔Correct Answer-
delays the arrival of the sound to the ear and separates stimulus artifact
The biomed safety analyzer is used to:
Measure the oxygen content of the patient's blood
Calibrate the stimulus output of the evoked potential equipment
Test the equipment for signs of biological contamination
Measure chassis leakage of equipment ✔Correct Answer-Measure chassis leakage of
equipment
All of the following are benefits of EEG monitoring during carotid endarterectomy except
detection of occlusion-associated ischemia
detection of hypotension
detection of heparin dosage
detection of hypoxia ✔Correct Answer-detection of heparin dosage
When using monopolar stimulation for direct nerve stimulation
the cathode electrode is connected to the negative terminal of the stimulator output
the cathode electrode is connected to the positive terminal of the stimulator output