Lecture 9/10: Medical and Surgical Management Flashcards
lifestyle modifications for lowered HTN
1kg weight loss = 1mmHg BP reduction
low sodium diet <1500mg
pharmacology to decrease fluid volume and increase vasodilation (combo of diuretics, ACE or ARB, and Ca channel blockers
function of diuretics
stops sodium reabsorption by kidneys = more urine
decrease fluid levels = decrease blood volume in circulation = decreases preload (less blood returning to heart so less needs to be ejected)w
what is a loop diuretic
most effective/most utilized
inhibits movement of K and Cl across membrane
not 1st line of defense; may want to first try something that doesn’t affect electrolytes so much; can be dangerous/need to replace
function of ACE inhibitors
acts on RAAS to reduce intravascular fluid to reduce preload
prevent normal increase in circulating blood volume
prevents normal vasoconstriction and increased SVR that LV has to push against
can’t be used with pts with lung disease due to side effects of smooth mm contraction of all-sized airways
inhibits conversion of And I to II (occurs in lungs)
function of Angiotensin receptor blockers (ARBs)
acts on RAAS to prevent normal vasoconstriction used to raise BP
Ang I gets converted to Ang II in lungs but And II is blocked from distal receptors
much safer for pts with lung disease
function of Ca channel blockers
stops Ca entrance into myocardium = coronary vasodilation
decreased myocardial contraction strength and O2 demand (LV doesn’t have to work as hard to meet body O2 demand)
acts on peripheral vasculature smooth mm to vasodilate
pharm goals for management of CAD
decreased myocardial O2 demand
increase myocardial O2 supply
strengthen LV contractility
sx management goals of CAD
reduce/remove atherosclerotic plaque
bypass blocked coronary arteries before progression to MI
Drugs that decrease O2 demand for those with CAD
BBs
CCBs
nitrates
Drugs that increase O2 supply for those with CAD
thrombolytics
anti-platelets
anticoagulants
drugs that increase LV strength
ionotropes
function of beta blockers
stops epi and norepi from binding to B1 and B2 receptors
nonselective BBs block both B1 and B2
cardioselective BBs only block B1 receptors to prevent unwanted respiratory involvement
methods of administration of nitrates
sublingual tablet
sublingual spray
sublingual powder
paste to spread on skin
transdermal patch
continuous IV drip (abbreviated gtt)
thrombolytics function
accelerate clot breakdown
normal clot lysis happens naturally over period of days to weeks
antiplatelets function
stops platelet adherence
doesn’t stop RBCs from sticking to one another, just prevents platelets from adding to clot formation
anticoagulant function
prevent clot formation
stops normal clothing cascade from occurring
types of inotropic meds
cardiac glycosides
sympathomimetics
phosphodiesterase inhibitors
arteriodilators (indirect ionotrope)
how do cardiac glycosides work
decrease active transport of Na and K to increase intracellular Na
how do sympathomimetics work
mimics action of epi/norepi to increase sympathetic NS drive
how do phosphodiesterase inhibitors work
increase myocardial contractility without altering the Na-K pump
how do arteriodilators (indirect ionotrope) work
decrease after load by decreasing arterial resistance (decreases SVR)
what is a PCI
percutaneous coronary intervention
can be performed electively or emergently
ACS - door to balloon time <90 min
typically used for 1-2 vessel blockage
catheter inserted bia distal artery to access coronary arteries with goal of restoring blood flow to cardiac mm
pts generally on 2 anti-platelets post sx to prevent thrombus (aspirin + plavix)
balloon angioplasty vs angioplasty with stent
balloon = Cath used to inflate balloon to open a blocked artery
stent = stent placed in place of inflated balloon to keep artery open; drug eluding stent is most common
indications for a coronary artery bypass graft (CABG)
lesions threatening major portions of myocardium
multi-vessel disease, especially L sided blockages
ongoing ischemia following MI
how does a CABG work
graft comes from internal mammary artery from internal chest wall or saphenous vein from leg
veins are cauterized, flushed with heparin, and inverted for normal blood flow
what is a sternotomy
most commonly used approach to access heart
suprasternal notch to xiphoid process
sternum is wired closed
soft tissue is sutured and glued
what is cardiopulmonary bypass (CPB)
heart cannot move during sx but body/brain still need perfusion
CPB initiated via cannulation at aorta and IVC/SVC
blood removed to oxygenator and returned straight to aorta for distribution
once CPB is complete, ice slush is poured into mediastinum to stop heart
what is an off pump CABG
heart is accessed from L sided thoracotomy
can only operate on L sided coronary aa
no CPB
less expensive, no sternal precautions, faster recovery
isolated portions of myocardium stopped via electrical “starfish”
describe what typically happens post op with CABG pts
straight from OR to CVICU (no normal sx post op)
RT and RN work to wean down ventilator support and wean off drops/sedation over the 1st 6 hours
goal = be extubated within 6 hours
monitoring of urine output, chest tube output, all sx sites, and external pacemaker
goal = pt in chair within 8 hours of arrival and standing within 12 hours (depends on unit and pt stability)
common CABG complications
pain
respiratory distress (15-20%)
impaired cognition/delirium (CPG “pump head”)
acute blood loss/cardiac tamponade (bleeding in pericardium/pressure)
increased risk clot burden; difficult to balance risk of CVA with risk of hemorrhage if anti-coagulated too soon post sx
dysthymia/ectopy
when is valve repair/replacement indicated
for symptomatic valve dysfunction
what is a valvuloplasty
minimally invasive repair (widening) using balloon Cath technology
risk of replacement outweighs repair
how does valve replacement work
mechanical or tissue (allograft or xenograft); mechanical required lifelong INR goal adjustment
can replace multiple valves in 1 sx
frequently done in conjunction with CABG
open repair requires sternotomy
what is transcatheter aortic valve replacement (TAVR)
minimally invasive prodecure to replace aortic valve
utilizes similar process as cardiac cath via femoral or radial artery access in Cath lab
valve replacement will always be mechanical
sometimes used if pt has high risk of open sx replacement
long term outcomes may not be as strong as open AVR
what is an external placemaker
set up as backup
typically 60 bpm
procedure of weaning away
what are chest tubes/JP drains used for
need to ensure no post op hematoma formation
what is a pulmonary artery catheter (PAC) for invasive monitoring of heart function
measures R atrial pressures, pulmonary aa pressure, CO, cardiac index, and temperature
inserted in RIJ or R subclavian, “floated down” the SVC, through RA, RV, and into pulmonary aa
held in place my sutures and adhesive dressing at neck
if dislodged, indwelling components can cause potentially fatal ectopy
what is an arterial line
invasive and instant BP measurement
usually in radial aa but can be femoral or brachial
if pressure in the line is lost, pt can bleed out
what is a central venous catheter
large IV placed in IJ, subclavian, or femoral vein
allows for meds/fluids to be given directly
line considerations
no mobility 2-4 hours post extubation to reduce risk of airway edema/stridor
no mobility 2 hours post central line removal to reduce risk of developing hematoma (especially in neck/groin)
femoral lines should not limit mobility but some facilities have restrictions
first approach to dysrhythmias
pharm management; want to stabilize cell membranes during action potential by controlling movement of electrolytes
other approaches to help dysrhythmias if pharm management doesn’t work
pacemaker
internal cardiac defibrillator (ICD)
variety of other electrophysiologic procedures or sx that can be dine if less invasive measures are unsuccessful
class I dysrhythmia meds
Na channel blockers
limits myocardial excitation and contraction
class II dysrhythmia meds
beta blockers
inhibits sympathetic NS
Class III dysrhythmia meds
K channel blockers
prolongs refractory period and makes it more difficult for myocytes to respond to stimulation from one another
class IV dysrhythmia meds
Ca Channel blockers
slows conduction through AV nodes
what is a permanent pacemaker (PPM) and how does it work
creates action potential in necessary areas
in L chest with leads inserted via cephalic vein through the SVC into R atrium, R ventricle, or L ventricle
can be single chamber, dual chamber, or biventricular
subcutaneous generator functions at a fixed rate, mode, with variety of settings and backup settings
indications for pacemaker
bradycardia
type II-III heart blocks
other uncontrolled arrhythmias
things to keep in mind about placement of permanent pacemaker
generator may need to be replaced if batteries run out
can interrogate PPM via external device to change settings, charge battery, turn off, etc
PPM post op precautions
complications of PPM
infection
lead movement/migration
bleeding, clots
no MRI, TENS, NMES
caution near magnets
what is a leadless pacemaker
new
does not require leads or L upper chest generator
inserted via femoral vein and IVC into RV
can influence RV or LV electrical activity based on location
what is an internal cardiac defibrillator
similar to PPM and fires in event of arrhythmia
leads inserted into AV node and ventricles
pts with EF <35% have higher chance of fatal ventricular fibrillation so sometimes ICD placed prophylactically
combination PPM-ICD devices if pt meets indications for both
indications for internal cardiac defibrillator
VFib
VTach
cardiac arrest
HF/CM with EF <35%
hypertrophic CM
combo heart block with ventricular arrhythmia
what is cardiac ablation
minimally invasive procedure that controls arrhythmia by creating scar tissue in myocardium
targets ectopic foci
might not permanently fix problem
what is a maze procedure
type of cryo ablation specifically used for persistent AFib
creates maze of scar tissue to block abnormal signals but allows normal impulse conduction
requires partially open or laparoscopic approach and frequently done in conjunction with other CTS
what is an atrial appendage and the clinical indication
both atria have extra tissue that can expand if needed
L atrial appendage is larger and can be more problematic
higher pressures on the L can case the LAA to expand and be a reservoir for blood
> 90% of clots that cause CVA originate in LAA
what is watchman’s procedure
presence of R or L atrial appendage increases risk of clot development in AFib
minimally invasive procedure via femoral or radial artery that “plugs” appendage to prevent clot formation
higher pressures in L side of heart create enlarged LAA
what is LAA or RAA surgical closure/when is it indicated
if watchman’s wasn’t successful or contraindicated, the atrial bulge can be surgically closed
can be done laparoscopically but also in conjunction with other open heart sx
what is cardioversion
electrophysiological procedure that restores normal rhythm
needs to be done in a highly monitored environment
can be done electively or emergently if pt is in fatal rhythm during MI or cardiac arrest situation
conscious sedation used for procedure
used frequently for AFib with RVR if meds aren’t controlling adequately
goals of pharm management for heart failure
maintain CO
fluid reduction to reduce preload
augment LV contractility and decrease after load
limit sympathetic nervous system action
HF medication types
diuretics
ACE/ARB
BBs
antiarrhythmics
Ionotropes
what is mechanical circulatory support
if LV isn’t functioning well enough to perfuse tissues, MCS can be used to supplement CO
various devices can be surgically inserted to improve heart function
what is an intra-aortic balloon pump
MCS device placed into proximal descending aorta via femoral, axillary, or subclavian artery
balloon attached to helium tank that inflates during diastole and deflates before systole
inflation = pushes blood into coronary aa while aortic valve is closed to provide optimal coronary cardiac output
deflation = suction of deflation assists with dropping after load and reducing work load on failing LV
what is an impella
MCS device placed into LV via femoral, axillary, or subclavian aa
mechanically pimps blood from LV into the aorta at a set rate
unloads the LV work and decreases myocardial O2 demand
what is a left ventricular assist device (LVAD)
implanted MCS device that replaces the workload of the LV and has a motor that controls blood flow at a set rate to maintain cardiac output
can be used as a bridge to transplant, temporary ventricular rest, or as destination therapy
longest living pt with LVAD = died after 15 years
components of LVAD
pump
drive line
controller
external power
batteries
machine weighs between 4-6 lbs
must have power source
no pulse
LVAD medications (in addition to typical meds for HF)
lifelong anti-coagulant (Life of the LVAD)
aspirin or plavix or both
pulmonary HTN meds to reduce R heart workload
supplements
LVAD complications
bleeding; LVAD cant function correctly if pt isn’t anticoagulated
bloot clots; device mechanism can case clots; prevalence is decreasing
R sided heart failure; device placement on L side can alter normal RV movement/function
drive line infections; soft tissues infections can migrate to heart
describe a heart transplant/important statistics
more pts on waitlist than will ever receive a heart
extensive medical, physiological, educational, and financial screening process
estimated 1st 5 year expense = $1.6 million
80-90% have 1 year survival rate
60% have 5 year survival rate
average survival is 12 years
what does it mean that pts who are candidates for heart transplants are on max medical management protocols
severe functional deficits
limited life expectancy
some must remain hospitalized until transplant becomes available
indications for OHT
end stage heart failure
congenital heart disorder
cardiomyopathy
Contraindications for OHT
age >75
severe mental/psychological instability
drug, tabacco, ETOH use w/I 6 mo
BMI >35
malnourishment
uncontrolled DM
PVD
severe lung disease
autoimmune disease with multi system involvement
AIDS
current/recent malignant cancer
other systemic illness with shortened life expectancy
J
process of heart transplant
- pt placed on waitlist after being deemed candidate
- geographic waitlist maintained by United Network of Organ Sharing (UNOS)
- when an organ becomes available, is matched to a pt based on various characteristics (age, blood type, size, etc)
- oran is preserved and transported to recipient
OHT medications
immunosuppressants: prevent organ rejection
corticosteroids: reduce inflammation/risk of rejection
antibiotics/antivirals: prevent illness in setting of immunosuppression
insulin: counteracts side effects of OHT meds that cause hyperglycemia
statins: improve long term outcomes, reduce risk of CAD in donor heart
Anticoagulants/anti-platelets: reduce risk of CAD in donor heart
OHT complications
infection
- highest risk 12 months post op
- opportunistic infections in setting of immunosuppression
rejection
- 50-80% in first 12 months
- symptoms of rejection = fever, fatigue, myalgias
very challenging to balance risk of rejection with infection
what is carotid endarterectomy
sx procedure to remove plaque build up frequently at CCA-ICA bifurcation
reduces CVA risk drastically
what is carotid stenting
implanted stent to open artery in area of atherosclerotic block
indications for AAA surgical repair/replacement
> 5cm or high rate of growth
rupture or + S&S
risk of dissection
describe the open sx approach for aortic repair/replacement
aorta repaired/replaced via open laparotomy incision
higher blood loss and open complications with open repair
describe endovascular aortic repair (EVAR)
can be done it pt is too high risk for open repair
vasculature accessed via B femoral aa
faster recovery and lower mortality/morbidity in short term
worse long term outcomes, higher rates of needing re-do sx
what is embolectomy/thrombectomy/atherectomy
removal of blood clot or atherosclerotic plaque
can be achieved in a variety of ways
what is balloon angioplasty and stenting
peripheral revascularization
very similar to cardiac PCI
