Comp Exam Review

Question 1

What are the risks associated with AVM embolization? (3)

Answer 1

cerebral edema
hemorrhage
hyperperfusion

Question 2

What is the time for cerebral ischemia from irreversible neuronal injury?

Answer 2

3-8 minutes

Question 3

What is the average blood flow in an adult per 100 g of tissue?

Answer 3

50 ml/100g/min

Question 4

What is the dose of mannitol to decrease brain size?

Answer 4

0.5 - 1 g/kg

Question 5

Where do intracranial aneurysms generally occur?

Answer 5

bifurcations

anterior portion of circle of willis

Question 6

What are the most common complications of subarachnoid hemorrhage? When?

Answer 6

rerupture (1-2 days)

vasospasm (4-14 days)

Question 7

What is the surgical approach for pituitary tumor?

Answer 7

transsphenoidal route if < 10 mm

bifrontal craniotomy > 20 mm

Question 8

What nerve is monitored during mastoid dissection?

Answer 8

facial nerve because it runs across the mastoid bone

Question 9

Why is the facial nerve monitored during mastoid dissection?

Answer 9

can provide surgeon with mechanical feedback during drilling and microdissection in the vicinity of the facial nerve

Question 10

Describe the methodology of transcranial cerebral oximetry.

Answer 10

Monitors regional oxygen saturation of Hb in the brain. A sensor is placed on the forehead and emits light of specific wavelengths and measures he light reflected back to the sensory

Question 11

What drugs are contraindicated when SSEP is employed? (3)

Answer 11

ketamine
etomidate (increases amplitude)
volatile anesthetics (use 1/2 MAC)

Question 12

What drugs are contraindicated in MEP monitoring?

Answer 12

NMB
volatile anesthetics (use 1/2 MAC)

Question 13

What is the most sensitive monitor for venous air embolism?

Answer 13

TEE

Question 14

What is the reference point for CPP monitoring?

Answer 14

external meatus

Question 15

What is the most common artifact with BIS monitoring?

Answer 15

EMG

Question 16

What are drugs that produce burst suppression?

Answer 16

volatile anesthetics
thiopental
propofol
etomidate

Question 17

Hypothermia decreases CMRO2 by how much?

Answer 17

1 degree Celsius = 6% change in CMRO2

Question 18

What are neuro-protective strategies? (4)

Answer 18

hypothermia
using neuro-protective anesthetics
Ca channel blockers
maintain optimal CPP

Question 19

What are ways to assess cardiopulmonary oxygenating ability? (3)

Answer 19

A-a gradient
a/A ratio > 0.75
cardiopulmonary shunt fraction

Question 20

What is the cardiopulmonary shunt fraction equation?

Answer 20

Qs/Qt = (CcO2-CaO2)/(CcO2-CvO2)

Question 21

When is an aintree catheter used?

Answer 21

FFOB via LMA or ETT

Question 22

What factors effect the half life of zofran?

Answer 22

hepatic impairment

Question 23

How do you calculate thoracic compliance?

Answer 23

change V/ change P

Question 24

What is the protocol for SBE prophylaxis for bronchoscopies and bronchoscopies that involve incision of the respiratory tract mucosa?

Answer 24

No SBE prophylaxis unless there is an incision of the respiratory tract mucosa.

Question 25

When is GI or GU tract SBE prophylaxis recommended?

Answer 25

infected with enterococcus or procedures on infected skin