Cardiac Anesthesia Part 1 continued and Part 2 Flashcards
what are the beneficial effects of mannitol as part of the pump prime solution
acts as an O2 free radical scavenger and a diuretic
what does hemodilution mean in relation to catecholamines
it also means a decrease in catecholamines
define the blood salvage strategy
mix the patients autologous blood with the prime solution
what does the LV vent do
drains thesbian veins
where does anterograde cardioplegia catheter go?
in the aortic root and sits proximal to cross clamp
where does retrograde cardioplegia catheter go?
coronary sinus
which comes first, cardiac arrest or cross clamp?
heart is arrested in diastole then cross clamp is applied. this is to ensure cardioplegia goes to the heart
what is long pump time associated with (neuro)
postoperative cognitive disorder
what are risks associated with postoperative renal dysfunction after bypass (6)
age, preexisting CKD, long pump time (>1h), DM1, nephrotoxic agents, vascular pathology
there is an activation of what and an increase in these two things on bypass
activation of extrinsic and intrinsic pathways
increase in angiotensin and free O2 radicals
when do you start re warming the patient
after seeing the last distal graft in. turn on warming blanket at this time
how long does it take to re warm a patient safely
30-40 minutes or about 1 degree celsius q3-5 minutes
where do you want to keep the BG to prevent infection
<200
how many joules for defibrillation after removal of cross clamp?
10-30 joules ( you may dial this in)
when do you start to turn on fluids and pressors while coming off of bypass
after lung reinflation (and de airing maneuvers), before cross clamp removal
what is an acceptable HCT while coming off pump
25-28
what do you give to decrease K
500mg CaCl
what do you give to prevent arrhythmias and decrease risk of afib
2-4g magnesium
special considerations if they did an internal mammary artery (/thoracic artery) to LAD while coming off bypass?
when inflating lungs, you can overstretch anastomosis easily. be aware
complications to aortic cross clamp (3)
hemorrhage (at cannulation site)
dislodgement of atheromas (clots)
aortic dissection
what do ST changes tell you as you are unclamping the aortic cross clamp?
tells the surgeon to look at the TEE for infarct versus air
when is the patient at the most risk for recall during CPB surgery
graft harvest, sternotomy, rewarming
dont give protamine until
all catheters are out. you want to make sure you do NOT have to go back on bypass
if the cardiac output is decreased but the blood pressure is ok, what would you consider
after load reduction or inotrope
how slowly do you give protamine
over 20-30 minutes
which ACT number would alert you that they need protamine
> 150
type 1 reaction from protamine
histamine release. slow the protamine, give volume, give neo/ephedrine PRN
type 2 reaction from protamine
IgE mediated, more like anaphylaxis but “not too problematic”. bronchoconstriction can occur
type 3 reaction from protamine
heparin protamine complex that lodges in pulmonary circulation. bad. not good.
do you give protamine via CVC or PIV
always PIV, never CVC
if you see a drop in BP during chest closure, what should you consider administering
an inotrope
typical heart transplant recipient picture
NYHA functional class IV with a predicted life expectancy <12 months EF <20%
most common indication for a heart transplant
idiopathic cardiomyopathy
contraindications to receiving a heart transplant
> 70 years old, chronic renal dysfunction, obesity
how is the anesthetic management timed for a transplant recipient
timed so CPB initiated when heart is available
what to look for pre op with heart transplant recipients
VAD, IABP, ICD, inotropic drug infusions
what type of induction, standard versus RSI for the transplant recipient?
RSI, considered full stomach since you “never know when youre receiving a heart”.
you want smooth rapid control of airway but do slow administration of medications
goal before heart arrives
get patient on CPB as fast as possible
when do you place lines on a heart recipient
before induction
maintain these three things to maintain CO for a heart recipient
HR and intravascular volume maintenance.
avoid a decrease in SVR
what do these patients take for an immunosuppressant protocol
high dose steroid and immunosuppressant drug
most common reason for inability to wean from CPB
right hear failure
medications you need to anticipate requiring for heart transplant
isoproterenol, epinephrine, phosphodiesterase inhibitors (milrinone), nitric oxide, inhaled prostaglandins
vasopressin in relation to SVR and PVR
preserves SVR without effect of PVR
post heart transplant HR
faster due to loss of parasympathetic tone
which receptors do you need to target for a post heart transplant patient to see an effect
need direct action on myocardial adrenergic receptors. basically make sure all of your drugs are direct acting
what are post heart transplant patients dependent on
volume (preload)
does the frank starling mechanism still apply post heart transplant to a denervated heart
yes
what are these heart transplant patients at risk for and how do they present
accelerated atherosclerotic disease. they dont have angina but will get arrhythmias
will you see bradycardia from fentanyl and anticholinergics in a denervated heart
no
are all reflexes post transplant gone?
no, some reflexes will be maintained
describe an off pump CABG (OPCAB)
immobilization of the heart by compression and/or suction of vessels theyre looking to treat
how to prevent hypotension and reduced coronary perfusion during an OPCAB
volume load
head down
pressors
-theres alot of hemodynamic changes with this approach so youre doing alot of utilization of these three mechanisms during this approach
what to consider as a negative effect of suction during OPCAB
can compromise native coronary artery flow
monitors and equipment to have during OPCAB
still use TEE
have bypass on standby
do you do heparin during OPCAB
may use low dose heparin
do you still do a sternotomy for an OPCAB
yes
describe a minimally invasive direct coronary bypass (MIDCAB)
grafting of single vessel ex) LIMA to LAD
what is the surgical approach to a MIDCAB
you can do this alot of ways including left anterior thoracotomy incision requiring one lung ventilation or even a Da Vinci approach
ventilation strategy for a MIDCAB?
lung isolation with double lumen ETT
is a MIDCAB an on pump case?
no, off pump for this case
MIDCAB HR, preload, Vt considerations
decrease HR to decrease VO2
increase preload
decrease Vt if not OLV
what medication should you have available for a MDICAB?
heparin
what should you have on the patient during a MIDCAB
defibrillation pads (and bypass on standby)
describe the surgical approach to a minimally invasive aortic and mitral valve replacement
can either do parasternal, thoracoscopy, partial hemisternotomy
where does the bypass insert on a patient receiving a minimally invasive aortic/ mitral valve replacement
femoral artery/femoral vein. there is apparently decreased bleeding related to this approach
access for a mini AVR and MVR procedure?
CVC
ventilation for a mini AVR and MVR procedure?
OLV/ DLT for lung isolation
two things to have on patient during mini AVR and MVR
transvenous pacers placed and tested
defibrillator pads
where else can a TAVR/TAVI be done
EP
approach to a TAVR/TAVI?
femoral artery or transapical (apex of LV)
anesthesia technique for TAVR/TAVI
can do IV sedation but usually GETA
access for a TAVR/TAVI?
large bore PIV, aline, CVC
may need fluoro to put in lines
TTE or TEE for TAVR/TAVI?
TEE if GETA, TTE if IV sedation
what should you have on the patient getting TAVR/TAVI
defibrillator pads
medications to have on standby during TAVR/TAVI
pressors
blood consideration strategies in cardiac surgery include (6)
antifibrinolytic drugs minimizing hemodilution cell saver retrograde priming of pump normovolemic hemodilution use of POC testing to support transfusion
platelet function is altered by these three things during cardiac bypass surgery
hemodilution
hypothermia
contact with CPB circuit
right ventricular dysfunction or failure may occur after CPB because of
inadequate myocardial protection or
inadequate revascularization with resultant RV ischemia
approaches to reduce inflammatory response during cardiac surgery
modification of surgical and perfusion techniques
circuit components
pharmacological strategies
even after uncomplicated cardiac surgery, a midline sternotomy (or thoracotomy) causes a significant reduction in these 3 pulmonary components
TLC, VC and FEV
