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