Miscellaneous Monitors & Radiology Flashcards
What percentage of receptors may still be blocked with a ToF of 0.9?
75%
At what percent blockade is T1of a ToF lost?
90-95% blockade
At what point is T2-T3 lost?
85-90%
At what point is T4 lost?
80-85%
Does cerebral oximetry measure regional or global oxygenation?
Regional
What degree of change is concerning in cerebral oxygenation?
> 25%
Cerebral oximetry uses ______ to measure oxygenation
Near infrared spectrometry (NIRS)
What percentage of blood in the brain is venous?
Almost 75%!
NIRS primarily measures:
venous oxygenation and oxygen consumption. Not arterial. It can’t detect pulsatile flow.
During anesthesia, EEG waves change in two ways:
They become slower (lower frequency)
The become taller (higher amplitude)
Which anesthetic increases EEG beta waves?
ONLY Nitrous
Is etomidate associated with epileptiform activity?
NO
Unilateral burst suppression is suggestive of:
Cerebral ischemia
Isoelectricity occurs at:
1.5-2 MAC
Light anesthesia is associated with ________ wave activity
beta
______ and _____ waves predominate during general anesthesia
theta and delta
The development of _______ during anesthesia may indicate cerebral ischemia
new delta
Which circumstances mimic ischemia on an EEG?
Deep anesthesia
HYPOcarbia
HYPOthermia
The accuracy of BIS monitoring is effected by:
Increased muscle tone
Encephalopathy
Ketamine
What is the target range for anesthesia with the Patient State Index (PSI)?
25-50
The LIM alarms if:
the sum of all leak currents exceeds 2-5 mA
The isolation transformer sits between:
the power company and the OR
