Monitoring Depth of Anesthesia

Question 1

When monitoring anesthesia depth, both cortical and subcortical activities need to be assessed?

Answer 1

True

Question 2

___ times more anesthetic is needed to inhibit movement than to inhibit consciousness

Answer 2

Three

Question 3

T/F: immobility can be used to ensure unconsciousness

Answer 3

false

Question 4

First part of CNS inhibited by anesthesia?

Answer 4

cortex

Question 5

Stage 1 of Guedel’s system describes _____

Answer 5

from drug administration to loss of consciousness

Question 6

What is likely to occur during stage 1?

Answer 6

excitement and violent struggle (maybe)
epinephrine release, tachycardia, pupillary dilation
irregular breathing, breath hold, coughing
salivation, urination, defecation
ataxia, recumbency

Question 7

Stage 2 of Guedel’s system describes _________

Answer 7

from loss of consciousness until onset of regular breathing

Question 8

What is likely to occur during stage 2?

Answer 8

state of delirium
struggling and exaggerated reaction to stimuli
epinephrine release, tachycardia, pupillary dilation
strong palpebral and eyelash reflexes
irregular breathing, breath holding, laryngeal spasm
vomiting, regurgitation, salivation
strong jaw tone, intubation not possible or difficult

Question 9

Stage 3 of Guedel’s system describes ________

Answer 9

from onset of regular breathing until cessation of effective breathing

Question 10

At what stage do you expect no movement in response to noxious stimuli?

Answer 10

Stage 3

Question 11

Describe Stage 3 plane 1

Answer 11

light anesthesia
nystagmus, lacrimation
weakening palpebral and corneal reflexes
no swallowing reflexes
pupils constricted
no involuntary movement
simple procedures/exams may be possible

Question 12

Describe Stage 3 plane 2

Answer 12

medium plane of anesthesia
progressive intercostal paralysis
stable respiration and pulse
loss of laryngeal reflexes
weak palpebral strong corneal reflexes
adequate muscle relaxation for most surgical procedures

Question 13

Describe Stage 3 plane 3

Answer 13

deep anesthesia
diaphragmatic breathing
pupils dilate, eyes central
no palpebral/corneal reflexes
some patients may have to be maintained at this stage, should ideally decrease to plane 2

Question 14

Describe stage 4

Answer 14

overdose

resp failure, cardiac arrest, death

Question 15

T/F: cardiovascular adverse effects are only possible if isoflurane is overdosed

Answer 15

false

Question 16

T/F: a patient is only considered hypotensive if it is too deep

Answer 16

false, can even be hypotensive if anesthesia is light

Question 17

What stage are most surgeries and intubation performed in?

Answer 17

Stage 3 plane 2-3

Question 18

What drug can cause nystagmus, blinking, central eye position and dilated pupils even at moderate anesthetic depth?

Answer 18

Ketamine

Question 19

3 goals for practicality

Answer 19

1) acceptable cardiovascular function
2) fully relaxed and immobile patient
3) least necessary anesthetic depth

Question 20

rotated eyes likely indicate stage ______

Answer 20

stage 3 plane 2

is ideal but not mandatory

Question 21

central eye and dilated pupils indicate:

Answer 21

either too light or too deep anesthesia

Question 22

nystagmus likely indicates

Answer 22

too light anesthesia

Question 23

____ may have slow nystagmus at light but appropriate anesthetic depth

Answer 23

horses

Question 24

spontaneous blinking likely indicates

Answer 24

too light anesthesia

Question 25

slow blinking may be seen in ______ and may be acceptable if everything else is okay

Answer 25

horses

Question 26

lacrimation may be seen at

Answer 26

light but appropriate depth especially in horses

Question 27

Should you perform corneal reflex?

Answer 27

no - may cause injury

Question 28

_____ tone indicates overall muscle tone

Answer 28

jaw

Question 29

The tongue should be _____

Answer 29

relaxed

Question 30

If spontaneous respiratory rate is high (>20br/min), may indicate?

Answer 30

too light anesthesia or low lung volume

Question 31

What can a changing RR and pattern in response to surgical stimulus be a sign of?

Answer 31

anesthesia may be too light or analgesia may be insufficient

Question 32

Common causes of increased heart rate?

Answer 32

surgical stimulus (nociception)
life threatening stress (hypoxemia)
anemia, hypovolemia, shock, hyperthermia

Question 33

common causes of decreased heart rate?

Answer 33

drugs or hypothermia