MONITORING: CNS sidenotes

Question 1

Ideal cerebral function monitor measuring the

Answer 1

electrical pattern of electrical activity from the depolarization of cortical neurons.

Question 2

Motor evoked potentials monitor

Answer 2

electrical activity produced by skeletal muscles when directly stimulated.

Question 3

SSEP monitor the _____Column

Answer 3

Dorsal column (sensory)

Question 4

SSEP are stimulated ________and recorded _____

Answer 4

peripherally ; centrally

Question 5

MEP assess the integrity of the

Answer 5

descending motor pathway in the ventral spinal cord

Question 6

MEP monitor the _____Column

Answer 6

Ventral column (motor)

Question 7

With MEP what is stimulated

Answer 7

Peripheral muscles are stimulated.

Question 8

The MEP is usually detected at what two muscles?

Answer 8

THENAR EMINENCE and ABDUCTOR HALLUCIS MUSCLE

Question 9

EP Least affected by VA

Answer 9

BAEPs

Question 10

EP most Affected by VA

Answer 10

VEP

Question 11

Correct order from MOST TO LEAST SENSITIVE TO VA

Answer 11

VEP>SSEP>BAEP

Question 12

Nerves that be stimulated to elicit SSEPs are

Answer 12

Posterial tibial
Medial
Peroneal
Ulnar

Question 13

SSEPs evaluated the integrity of the brain or spinal cord during certain types of surgery by monitoring

Answer 13

Gracilis and cuneatis tracts of the posterior spinal cord.

Question 14

Burst suppression is a

Answer 14

reversible decrease in cortical neuronal metabolic function (CMRO2)

Question 15

Characteristic signal often recognized with deepening of anesthesia levels

Answer 15

Burst suppression

Question 16

Burst suppression is caused by

Answer 16

Barbiturates and propofol

Question 17

Complete EEG suppression occurs at what temperature

Answer 17

15-18C

Question 18

BURST SUPPRESSION occurs at what MAC of VA?

Answer 18

~1.5 Iso, DES, sevo

Question 19

Burst of those agents can turn into epileptic seizures

Answer 19

Sevo and enflurane

Question 20

Barbiturates on EEG

Answer 20

Reduces EEG electrical activity as much as 50%, dose dependent

Question 21

In normothermic patient, CBF volume of 20-50 ml/100g/min been associated with

Answer 21

Slowing on the EEG

Question 22

Normal CBF is

Answer 22

50ml/100g/min

Question 23

CBF associated with significant neurologic impairment

Answer 23

<18 ml/100g/min

Question 24

CBF where EEG waveforms are completely abolished

Answer 24

<12 ml/100g/min

Question 25

CBF is irreversible at

Answer 25

< 6 ml/100g/min

Question 26

List 4 EEG waveforms from LOW to HIGH frequencies

DTAB

Answer 26

Dela < Theta < Alpha < Beta

Question 27

Delta frequency

Answer 27

1-4 Hz

Question 28

Theta Frequency

Answer 28

4-8 Hz

Question 29

Alpha Frequency

Answer 29

9-14 Hz

Question 30

Beta Frequency

Answer 30

15-40 Hz

Question 31

Most feared complications of spinal surgery

Answer 31

Paraplegia

Question 32

2 methods to detect intraoperative spinal cord function compromise?

Answer 32

Wake-up test

SSEPs

Question 33

SSEP and wake up monitor the ______column pathways

Answer 33

Dorsal

Question 34

If acute alterations in SSEP amplitude or latency occur what does it signify?

Answer 34

spinal cord compromise, ischemia, compression or hematoma

Question 35

If acute alterations in SSEP amplitude or latency occur and there is possible spinal cord compromise what should be done?

Answer 35

Surgery be discontinued, and BP return to normal or 20% above normal.

Question 36

What is EMG

Answer 36

It is a technique for evaluating and recording the electrical activity produced by skeletal muscles.

Question 37

What is the GOLD STANDARD for monitoring patients undergoing CAROTID ENDARTERECTOMY under GA?

Answer 37

12-lead EEG

Question 38

Beside the GOLD STANDARD Of 12-lead EEG for patients undergoing CEA what other pressures can be used?

Answer 38

TCD

Stump pressures.

Question 39

Shivering cause O2 consumption to increase by

Answer 39

200%

Question 40

An opioid agonist commonly used to stop shivering is

Answer 40

Meperidine

Question 41

Best sensors when comparing accuracy, safety and cost

Answer 41

ESOPHAGEAL (should be placed in the lower half or third of the esophagus behind the heart )

Question 42

What prevents phase I hypothermia and How?

Answer 42

Prewarming a surgical patient in the preoperative area for at least 30 minutes effectively prevents phase I hypothermia by eliminating the CENTRAL-PERIPHERAL temperature gradient.