Miscellaneous monitors & equipment Flashcards
Choose the statements that MOST accurately describe the Bispectral Index monitor. Select 2
a. ketamine falsely elevates the BIS value
b. the BIS value is calculated in real time
c. The BIS value and Patient Safety index value are interpreted in the same way
d. Burst suppression begins at a BIS value of 20
a. ketamine falsely elevates the BIS value
d. burst suppression begins at a BIS value of 20
The bispectral index monitor uses a computer algorithm that translates raw EEG data into
a number between 0-100
A BIS value of 100 indicates
fully awake
A BIS value of 80 indicates
moderate sedation
A BIS value of 40-60 indicates
general anesthesia
A BIS value of 40 indicates
a deep hypnotic state
A BIS value of 20 indicates
burst suppression
A BIS value of 0 indicates
absence of electrical activity
The accuracy of the BIS is affected by
hypothermia
EMG interference (increased muscle tone)
encephalopathy
ketamine
The patient state index is similar to the BIS, however the target range for general anesthesia is
25-50
As the level of anesthesia becomes deeper, the EEG waveforms exhibit a
lower frequency
higher amplitude
The BIS is less accurate in
children
Select the statement that MOST accurately describes the function of the line isolation monitor.
a. if a piece of equipment becomes grounded, it cuts off the power supply to that piece of equipment
b. it protects the patient from microshock
c. The alarm sounds when the OR power supply becomes grounded
d. It isolates electrical equipment from the ground
c. the alarm sounds when the OR power supply becomes grounded
An electrical current that enters the body will exit the body along
the path of least resistance
Consequences of electrical injury include
cardiac arrhythmias
nerve injury–> muscle contractions & diaphragmatic paralysis
thermal injury
_________ is a comparatively larger amount of current that is applied to the external surface of the body.
Macroshock
One-hundred millamperes can cause
ventricular fibrillation
_________ is a comparatively smaller amount of current that is applied directly to the myocardium
Microshock
The electrical systems in the OR are designed to reduce
the risk of electric shock
The risk of electrical shock in the OR is minimized because the OR power supply is _____________ and the equipment is _____________
NOT grounded; grounded
For a shock in the OR to occur, there must be two faults in the system:
first fault- the OR power supply becomes grounded
second fault- the circuit is complete & electric shock occurs
The line isolation monitor assess the integrity of
the ungrounded power system in the OR
The line isolation monitor will alarm if
the sum of all currents exceeds 2-5 mA
If the line isolation monitor alarm sounds,
the last piece of equipment that was plugged in should be unplugged
Electricity obeys _________ law
Ohm’s
Voltage is equal to
current x impedance (resistance)
To receive a shock, a person must
become part of and complete an electrical circuit
_______________ increases the patient’s susceptibility to microshock.
A central line, PA catheter or pacing wires b/c they provide a direct conductive pathway to the heart
An _______________ is required to supply the ungrounded power to the OR.
isolation transformer
Choose the statements that BEST describe the surgical electrocautery unit. (select 2)
a. the return pad grounds the patient
b. electrocautery can suppress pacemaker function
c. bipolar electrocautery requires a return pad
d. a return pad that is too small increases the risk of thermal injury
b. electrocautery can suppress pacemaker function
d. a return pad that is too small increases the risk of thermal injury
The surgical electrocautery device delivers a
high-frequency current that is used to cut, coagulate, dissect, or destroy tissue
When a monopolar device is used, a
grounding pad is applied to the patient
If the return pad fails, the patient is
at risk for burns
The electrical energy from the electrocautery unit exits the body via
the return pad
The current return must not pass across
a pacemaker
A bipolar device does
not need a return pad b/c the forceps contains the active as well as the return electrode
Is vfib a risk with electrocautery?
No b/c it doesn’t affect excitable cells
To prevent burns at the return pad site, the entire surface of the return
electrode should be in direct contact with the patient’s skin and it should not be placed over bony prominences or metal implants
If ______________ is used, then all metal jewelry should be removed because any metal on the patient can form capacitive coupling & increased burn risk
a capacitative-coupled return electrode
