Comp Exam Review Flashcards
What are the risks associated with AVM embolization? (3)
cerebral edema
hemorrhage
hyperperfusion
What is the time for cerebral ischemia from irreversible neuronal injury?
3-8 minutes
What is the average blood flow in an adult per 100 g of tissue?
50 ml/100g/min
What is the dose of mannitol to decrease brain size?
0.5 - 1 g/kg
Where do intracranial aneurysms generally occur?
bifurcations
anterior portion of circle of willis
What are the most common complications of subarachnoid hemorrhage? When?
rerupture (1-2 days)
vasospasm (4-14 days)
What is the surgical approach for pituitary tumor?
transsphenoidal route if < 10 mm
bifrontal craniotomy > 20 mm
What nerve is monitored during mastoid dissection?
facial nerve because it runs across the mastoid bone
Why is the facial nerve monitored during mastoid dissection?
can provide surgeon with mechanical feedback during drilling and microdissection in the vicinity of the facial nerve
Describe the methodology of transcranial cerebral oximetry.
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
What drugs are contraindicated when SSEP is employed? (3)
ketamine
etomidate (increases amplitude)
volatile anesthetics (use 1/2 MAC)
What drugs are contraindicated in MEP monitoring?
NMB volatile anesthetics (use 1/2 MAC)
What is the most sensitive monitor for venous air embolism?
TEE
What is the reference point for CPP monitoring?
external meatus
What is the most common artifact with BIS monitoring?
EMG
What are drugs that produce burst suppression?
volatile anesthetics
thiopental
propofol
etomidate
Hypothermia decreases CMRO2 by how much?
1 degree Celsius = 6% change in CMRO2
What are neuro-protective strategies? (4)
hypothermia
using neuro-protective anesthetics
Ca channel blockers
maintain optimal CPP
What are ways to assess cardiopulmonary oxygenating ability? (3)
A-a gradient
a/A ratio > 0.75
cardiopulmonary shunt fraction
What is the cardiopulmonary shunt fraction equation?
Qs/Qt = (CcO2-CaO2)/(CcO2-CvO2)
When is an aintree catheter used?
FFOB via LMA or ETT
What factors effect the half life of zofran?
hepatic impairment
How do you calculate thoracic compliance?
change V/ change P
What is the protocol for SBE prophylaxis for bronchoscopies and bronchoscopies that involve incision of the respiratory tract mucosa?
No SBE prophylaxis unless there is an incision of the respiratory tract mucosa.
When is GI or GU tract SBE prophylaxis recommended?
infected with enterococcus or procedures on infected skin
