trial Flashcards
What are some signs of venous engorgement when bypass begins?
pale and purple face, high CVP, facial edema
What does a high CVP immediately after bypass initiation signify?
If Bicaval: cannula could be incorrectly placed, or sinched.
If not Bicaval: cannula against wall or zygus vein.
What should CVP initially be after bypass initiation?
around 5
Who controls the inhalation gas during bypass?
perfusion. Make sure its on.
How much volume is the pump prime?
800-1200mL
What happens to O2 delivery if your patient is anemic before bypass and then the pump prime is infused?
DO2 decreases
What is the goal Hgb/Hct during bypass?
8
>20%
What is the goal urine output during bypass?
1mL/kg
What does hypothermia do to metabolic demands?
decreases
How fast should the patients core temperature be raised after bypass?
0.3 C/minute
What are complications of coming off of bypass cold?
V-fib, bleeding issues
What is the blood glucose goal during bypass?
<180
Which type of bypass pump moves blood by sequential compression of tubing by a roller.
Roller Pump
How is CO on a roller pump determined?
SV of each revolution
What are advantages of roller pump?
simple and effective, low priming volume.
Is CO on roller pump afterload independent or dependent?
independent
What does a clamped arterial line on a roller pump lead to?
high pressure and rupture
What does an obstructed inflow cannula on roller pump cause?
microbubbles
Which type of bypass pump leads to damage to blood components and potential for massive air embolus?
roller pump
Is CO on centrifugal pump afterload independent or dependent?
dependent
If your patients SVR is high with a centrifugal pump how is CO affected?
CO is decreased
What happens to blood flow if a centrifugal pump is off and not clamped?
flows backward through the pump
If line becomes occluded, on centrifugal the pumps will/will not generate excessive pressure?
will not generate excessive pressure
Does inflow obstruction on a centrifugal pump cause cavitation or microbubbles?
No, not enough negative pressure is generated
What is the most commonly used cardioplegia solution?
buckberg
What is a disadvantage of buckberg cardioplegia solution?
poor myocardial recovery
Poor myocardial recovery with buckberg cardioplegia is due to accumulation of these ions?
sodum and calcium
Cardioplegia delays which phase of the myocardial action potential?
phase 3
What is the blood:crystalloid mixture of buckberg cardioplegia?
4:1
What is the final Hct of buckberg cardioplegia?
16-20%
How much potassium does high and low buckberg solution contain?
high 100 mM KCl
low 50 mM KCl
Does Del Nido cardioplegia increase or reduce energy consumption?
reduce
One disadvantage of Del Nido cardioplegia is that is results in what?
hemodilution
What is the blood:crystalloid mixture of Del Nido cardioplegia?
1:4
Besides blood and crystalloid, what does Del Nido cardioplegia contain?
mannitol, potassium, lidocaine, magnesium
How often are buckberg and Del Nido cardioplegia delivered?
buckberg 20-25 minutes
Del Nido 40-80 minutes
Antegrade cardioplegia is delivered to the myocardium through the coronary arteries via the ____?
ostia
What is the perfusion pressure for integrade cardioplegia?
70-100mmHg
Which delivery of cardioplegia is contraindicated with AV regurg?
antegrade
In the absence of collateral vessels, uneven distribution of cardioplegia may occur due to what?
severe CAD
Retrograde cardioplegia is delivered through the coronary veins via the ____?
coronary sinus
What pressure is retrograde cardioplegia delivered at?
40mmHg
Which route of cardioplegia may be not adequately protect the RV due to catheter placement?
retrograde
What is the potassium concentration of cardioplegia?
8-10mEq/L
During cardioplegia b/c the concentration of potassium remains ____ in the ___ space, the membrane remains ____.
elevated
extracellular
depolarized
Do we want cardiac arrest to occur in diastole or systole?
diastole
What is the single best indicator of body temperature?
core
Accuracy of bladder temperature decreases with what?
low urine output
Gases are ___ soluble in a ___ solution.
more
colder
What does warming too quickly cause?
gaseous emboli
During weaning of CBP what are the C’s to remember?
cold, conduction, calcium, CO, cells, coagulation
During weaning of CBP what are the V’s to remember?
ventilation, vaporizer, volume expanders, visualization
During weaning of CBP what are the P’s to remember?
previous abnormality, protamine, pressure, pressors, pacer, potassium
Where can air collect during weaning of bypass?
pulmonary veins, LA and LV
Recall is common during sternal split and ____?
rewarming
What is a normal/goal calcium during weaning CBP?
4.6-5mg/dL
What is the goal Hgb/Hct during before terminating CBP?
Hgb >8g/dL
Hct 22-25%
How do you perform recruitment when reinflating the lungs?
30cm pressure for 15-20 seconds
When is protamine administered?
not until venous cannula and root vent is clamped
When first refilling the heart after CBP, where will pulsatilla be noticed first?
PAC
What is goal SBP for terminating bypass?
> 90
What is the goal CI following bypass termination?
> 2-2.2
What is the order of cannula removal?
venous, root vent, give protamine, aortic
How fast should protamine be given?
over 10-15 minutes
What does protamine cause that you should be aware of?
hypotension
Patients that separate from CBP easily with little/no support usually have what?
good pre-op LV function and few comorbidities
How do you treat a patient with significant LVH and diastolic dysfunction after coming off pump?
Crystaolloid to maintain adequate LVEDV
Low does vasoconstrictor
May need vasodilator to keep SBP within appropriate ranges
Patients with persistent hypotension in the post-CBP period may have what?
vasoplegic syndrome
Patients with persistent hypotension in the post-CBP period should be treated with what?
vaso, epi, methylene blue
phenylephrine/levo on pump
How are patients that come off of pump with LV failure treated?
inotropes and afterload reduction
How are patients that come off of pump with RV failure treated?
nitric oxide, milrinone, epinephrine
How are patients that come off of pump with biventricular failure treated?
mechanical support like ECMO
Does hypothermia have a direct or indirect relationship with metabolism rates?
direct
What should venous saturations be for circulatory arrest?
> 95%
nasopharyngeal temperature should be around what temperature during cooling for circulatory arrest?
18 Celcius
Describe blood flow during retrograde cerebral perfusion?
arterial blood through SVC
blood empties into the aortic arch
What are the normal flow rates and pressure in retrograde cerebral perfusion?
300-500mL/min
pressure of 20-25
How do you reinitiate brain perfusion prior to rewarming after circulatory arrest?
low flow cold blood
To prevent formation of gas emboli what should the temperature gradient be during rewarming after circulatory arrest?
<10 celsius
During rewarming after circulatory arrest temperature should not exceed what?
36 celsius
transgastric mid papillary short axis view gives you great visualization of …?
global ventricular systolic function. Function post bypass.
IABP reduces ___ and increases ____
reduces afterload
increases diastolic coronary perfusion
What are the five indications for IABP?
Cardiogenic shock MI Intractable angina Arrhythmias Help wean CPB/ECMO
What are the four contraindications for IABP?
Sepsis
Descending aortic disease
Severe PVD
Severe aortic regurgitation
What two gases fill a IABP?
helium or CO2
Where should the tip of the IABP be on x-ray?
2cm distal to left subclavian artery. 2nd intercostal space.
IABP inflates when the aortic valve opens or closes?
closes
What signifies aortic valve closure on A-line?
dicrotic notch
IABP inflation:
____ coronary artery perfusion
____ myocardial O2 delivery
increases both
IABP deflates at what wave of the EKG?
R wave
What lab value should be monitored during IABP use?
platelets
What is the air used to remove CO2 from the blood on ECMO?
sweep
Which lab specifically looks at heparin?
Anti 10a
What anesthetic is best for ECMO?
TIVA
What standard monitor is helpless in VADs?
BP cuff
What is the #1 limiting step in LVAD?
driveline infection
LVADs are very ___ and ____ dependent?
preload and HR
LVADs have a fixed ____?
CO
Which fluid should you infuse to a VAD patient?
NS
What console parameters give you an indication for volume status?
power and speed
If your patient has an AICD what function should be turned off for surgery?
defibrilator
If your patient is dependent on their pacemaker which mode should be programmed for surgery?
asynchronous
Lithotrpsy, TUR and uterine hysteroscopy, MRI, ECT, Nerve stimulator testing/therapy all cause pacemaker ___?
interference
What three pacemaker letters indicate asynchronous mode?
DOO or VOO
The pacing chamber is which of the three pacemaker setting letters?
1st
The sensing chamber is which of the three pacemaker setting letters?
2nd
The response to sensing is which of the three pacemaker setting letters?
3rd
If the pacemaker is set to DDD @60. Will you see pacemaker spikes if their HR is 70?
no
If your patient has a pacemaker what is the preferred method of cautery?
bipolar for short bursts
Where are pacemaker leads placed if its a biventricular pacemaker?
coronary sinus
If you increase the sensitivity on the pacemaker, it is ___ likely to fire?
less
On pacemakers, are you adjusting sensitivity to their intrinsic rate or the pacemaker settings?
intrinsic
“increasing sensitivity to their intrinsic rate?
If you decrease the sensitivity on the pacemaker, it is ___ likely to fire?
more
A pacemaker spike without a corresponding beat is called?
failure to capture
Cautery interference in a patient that is pacemaker dependent, not set to asynchronous mode will lead to what?
over-sensing and under pacing
When your pacemaker is firing when it shouldn’t be is called?
under sensing, over pacing
How do you treat under sensing, over pacing?
increase the sensitivity
If your pacemaker is set to AV pace but you are only seeing some of the V beats come through, what is going on?
failure to capture
How do you treat failure to capture?
increase the mV.
What does TEG measure?
ability to form a hemostatic plug
Your patient is a little oozy (EBL 3L), and your R time on TEG is prolonged, what is the treatment?
give more protamine
What does the R time on TEG represent?
time to begin forming a clot
What does the K time on TEG represent?
time until clot has achieved fixed strength
What does the alpha angle on TEG represent?
speed of fibrin accumulation
What does the MA on TEG represent?
highest vertical amplitude, clot strength
What does the A60 on TEG represent?
height of the vertical amplitude 60 minutes after max amplitude
What TEG values alert to a problem with coagulation factors?
R time
What TEG values alert to a problem with fibrinogen?
K time, alpha angle
What TEG values alert to a problem with platelets?
MA
What TEG values alert to a problem with excess fibrinolysis?
A60
How do you treat a TEG with an Increased R time?
FFP
How do you treat a TEG with a decreased alpha angle?
cryo
How do you treat a TEG with a decreased MA?
platelets (DDAVP)
How do you treat a TEG with an increased A60 (fibrinolysis)?
Txa
Which layers of blood vessels made of collagen?
tunica externa or tunica adventitia
Which blood vessel layer is made of smooth muscle cells and elastin?
tunica media
Which blood vessel layer is made of endothelial cells?
tunica intima
Which type of HTN has an identifiable cause?
2ndary
How is HTN diagnosed?
2 reading taken 5 minutes apart, sitting
The risk of CVD ______ with each increment of 20/10mmHg above 115/75mmHg.
doubles
What is normal, preHTN, stage 1 and stage 2 HTN?
normal 120/80
pre up to 140/90
stage 1 up to 160/100
stage 2 over 160/100
What does the juxtaglomerular apparatus secrete to maintain normal intravascular volume?
renin
What causes vascular stiffness in the intima?
collagen and metalloproteinases
intraoperative cardiac morbidity increase when DBP is greater than what?
110
HTN shifts the auto regulatory curve to the ____
right
HTNive patients are ___volemic and ___dynamic
hypovolemic and hyperdynamic
Atherosclerosis can be caused by which other disease?
diabetes
Atherosclerosis is an ____ disorder.
inflammatory
What are the three phases of atherosclerosis?
- fatty streak
- plaque progression
- plaque disruption
What are the biggest risk factors for atherosclerosis?
DM and cigarettes
What is the most effective medical therapy for atherosclerosis?
smoking cessation
What is the gold standard for diagnosing atherosclerosis and PAD?
angiography
What is the single best initial screening for suspected PAD?
ankle-brachial index
What ankle brachial index indicates a normal index?
> 1
An ankle brachial index of ____ indicated limb threatening ischemia?
< 0.4
Patients who develop ___ have 4-5x increase in post-op mortality
kidney injury
What is the most predictive factor of post-op renal function?
preop function. GFR, BUN, creat
What is the most effective way to prevent post-op lung complications?
post-op lung expansion
AA surgery is an independent risk factor for what?
delirium
Does intraoperative MI or stroke lead to worse outcomes?
MI
monocular blindness caused by emboli traveling into the internal carotid artery and eventually limiting flow through the ophthalmic artery.
amaurosis fugax
Common comorbidities for pt undergoing Carotid Endarterectomy ?
CVA, CAD, Diabetes, Renal disease
CBF is constant between a MAP of
60-160
What is the rate of CBF?
50ml/100g/min
what is the most sensitive and specific measure of adequate CBF?
awake patient
what is the gold standard for identifying neurological deficits?
EEG
What are the anesthetic goals during CEA?
maintain cerebral blood flow and decrease cerebral ischemia
what should be avoided during CEA? 4
Hyperglycemia
Hemodilution
Hypercarbia
Large swings in blood pressure
Which anesthetic agent does not impair cerebral auto regulation?
propofol
