Cardiovascular Flashcards
atrioventricular valves control blood flow from the _________ and they are the __________
atria to ventricle; mitral (left) (bicuspid) and tricuspid (right)
semilunar valves control flow from ________ and are the ________
ventricles to pulmonary artery or to the aorta; pulmonic semilunar valve and septic semilunar valve
blood flow through the heart/body
vena cava -> right atria -> tricuspid valve -> right ventricle -> pulmonary valve -> through pulmonary artery and to lungs -> returns from lungs as oxygenated blood and comes back into the left atria through the pulmonary veins -> mitral valve -> left ventricle -> out aorta and to the rest of the body
systole is the
ventricle contracting and sending blood out to the body
diastole is the
ventricles relaxing and filling up with blood from the atria
action potential is
the explosion of electrical activity created by depolarize event which is how the heart knows when to contract and relax. Depolarization = contraction (systole) Repolarization = relaxation (diastole)
order of electrical conduction system
SA node -> AV node -> bundle of His -> bundle branches R and L -> purkinje fibers
primary pacemaker of heart is the
SA node
secondary pacemaker of the heart
AV node
preload
amount of blood returning to R side of heart
after load
pressure against which the L ventricle must pump to eject blood
compliance
how easily the heart muscle expands when filled with blood
contractility
strength of contraction of heart muscle
stroke volume
volume of blood pumped out of the ventricles with each contraction
cardiac output
amount of blood heart pumps through circulatory system in a minute
autonomic nervous system control of the heart
sympathetic - increase electrical conductivity and myocardial contraction (epi and norepi)
parasympathetic - slow conduction of action potentials through the heart, reduce strength or contraction (acetylcholine)
Beta adrenergic receptors
B1 - in heart: increase HR and contractility (chronotropy and intropy)
B2 - in lungs: causes bronchodilation
ejection fraction
amount of blood ejected per heartbeat - should be 55% or higher; indicated ventricular function
stroke volume is determined by
preload, after load, contractility
cardiac output equation
CO = SV x HR
why is CO important?
tissue perfusion
end organ function
delivery of oxygen and nutrients
S&S or poor CO
decreased LOC
chest pain, weak peripheral pulses
SOB, crackles, rales
cool, clammy, mottled extremities
decreased urine output
causes of decreased CO
bradycardia, arrhythmias, hypotension, MI, cardiac muscle disease
causes of increase CO
sometimes increased blood volume and tachycardia, medications including ACE inhibitors, ARBS, nitrates, inotropes
normal CO
4-8 L/min
Central venous pressure
2-6 mmHg
MAP define
average arterial pressure throughout one cardiac cycle - systole and diastole
MAP normal
70-100 mmHg
MAP must be at least ____ for adequate perfusion of vital organs
60 mmHg
systemic vascular resistance define and normal
resistance exerted on circulating
blood by the vascular of the body
800-1200
antihypertensives
ACE inhibitors, ARBs, Calcium channel blockers, beta blockers, arterial and venous dilators
ACE inhibitors
reduce after load by acting on RAAS - blocks conversion of angiotensin (less volume = less pressure), increases renin levels, decreased aldosterone leading to vasodilation
Nursing considerations ACE inhibitors
dry cough (discontinue), monitor BP, angioedema, contraindicated during pregnancy
ACE inhibitors end in
-pril
ARBs end in
-sartan
ARBs
inhibits vasoconstrictive properties of angiotensin
ARBs nursing considerations
monitor BP, monitor fluid levels, monitor renal and liver status, contraindicated during pregnancy
Calcium channel blockers end in
-ipine or -pril
Calcium channel blockers
block transport of calcium into muscle cells inhibiting excitation and contraction (cause Ca acts as a sedative so by blocking it we are doing the opposite) inhibits excitation and contraction, causes peripheral vasodilation
nursing considerations for calcium channel blockers
avoid grapefruit, monitor bp (orthotic hypotension), can cause gingival hyperplasia
arterial dilators
cause decreased BP, arterial vasodilation, reduction in after load, increased CO
Hydralazine and minoxidil
venodilators
reduce preload, reduce venous returns to the heart, dilates arteries at higher doses
nitrates
betablockers end in
-lol
betablockers
antiarrhythmic; blocks beta 1 and 2 adrenergjc receptors which slow the heart rate
can also help with htn
beta blocker nursing considerations
do not discontinue abruptly, can mask signs of hypoglycemia, can potentially cause bronchospasm (caution with asthma and COPD)
by influencing the electrolytes going in and out of the heart we can control the __________________
electrical activity
amiodarone
potassium channel blocker, antiarrhythmic, stops potassium from leaving cells and prolongs rest period
amiodarone nursing considerations
dizziness, tremors, ataxia, pulmonary fibrosis, bradycardia, heart block, blue gray skin discolouration, has iodine and can disturb thyroid, not given in pregnancy
Adenosine is used for
SVT
adenosine is the medication version of _______________
cardioversion
Nursing considerations for adenosine
there will be a period of asystole
needs to be a rapid push or it will not work
client will feel “like they have been kicked in the chest”
adenosine needs to be used with caution in pts with _____________
asthma
Atropine is use for
excessive scretions (anticholinergic), sinus bradycardia, heart block
atropine needs to be avoided in pts with
glaucoma
atropine increases the _________ and causes _____________ which _________ secretions
heart rate; bronchodilation; decreasing
pts on atropine need to monitored for
urinary retention and constipation
the drug that is a cardiac glycoside is
digoxin
digoxin is given for
HF, afib, aflutter, CHF, cardiogenic shock
digoxin increases ________ and decreases ____________
contractility; rate
increase in heart contractility is also called a
positive inotrope
decrease in heart rate is also called a
negative chronotropy
early S&S of digoxin toxicity
n/v, anorexia, vision changes - yellow/green halos
late S&S of digoxin toxicity
bradycardia
arrhythmias
risk factors for digoxin toxicity
hypokalemia
loop diuretic
licorice extract (acts like aldosterone)
hypomagnesemia
hypercalcemia
elderly; decreased renal and liver function
should hold a digoxin dose when
the heart rate is less 60
antidote for digoxin is
digoxin immune fab
inotropes ___________ and examples
increase contractility of heart; dopamine, dobutamine, milrinone
vasopressors ________ and examples
cause constriction of blood vessles helping to increase bp; norepi, epi, vasopressin, phenylephrine
vasopressors are commonly given when
pt is hypotensive and we need to increase the preload to increase the cardiac output
Peripheral vascular disease (PVD)
inadequate venous return over a long period causing pathologic ishcemia; blood flow back to heart is affected
PVD S&S and Tx
brown disocoloration, uneven wound edges around ankle, swelling, pedal pulse will still be present
Tx: elevate legs, proper wound care
DVT
clot that remains attached to the vascular wall; caused by venous stasis, vein wall damage, hypercoaguable states
DVT tx
anticoagulants
prevent by promoting venous return
Superior Vena Cava Syndrome
tumor compressing SVC - blood cannot drain from upper body; will most commonly be seen in oncologic pts
Superior vena cava syndrome S&S
headache, blurry vision, non-pulsatile distended neck veins, distention of thoracic veins, facial plethora, glossitis, dyspnea, upper extremity edema
Atherosclerosis
inflammatory disease; plaque builds up an causes decrease blood flow to the areas they are located
atherosclerosis is the most common cause of
coronary artery disease and CVA
Hypertensive crisis is a bp over
> 180 / >120
htn S&S
often asymptomatic until severe - dizziness, headaches, vision chnages, angina, nose bleeds, SOB
htn medications
ACE inhibitors
beta bockers
Calcium channel blockers
diuretics (get rid of fluid to take pressure off of heart)
orthostatic hypotension
BP drops when client changes from lying to sitting to standing; client may faint; falls can cause serious injury
Aneurysm
localized dilation of a vessel wall - most common is aorta
causes of aneurysm
atherosclerosis, htn, smoking, hx
AAA S&S
gnawing, sharp pain
abdominal and back pain
thoracic aortic aneurysm S&S
back pain, hoarseness, struggling to swallow, SOB
rupture of an aneurysm causes a
hemorrhage
embolism
clot that dislodges and is mobile and can occlude the vasculature
at riks clients for an embolism
pregnancy (hypercoaguable, amniotic fluid can be forced into blood stream), a fib, long bone fracture (pelvis and femur)
substance an embolism can be
fat, air, bacteria, blood clot, amniotic fluid
high risk for air embolism are pts with
CVC or arterial catheter
position pt with air embolism or to prevent one when removing CVL in ______________ and why?
durant’s maneuver - left lateral trendelenburg; prevents air embolism from lodging into lungs
fat embolism S&S
hypoxia, dyspnea, tachypnea, confusion, altered LOC, petechial rash (sometimes) - symptoms dependent on where it is lodged and treatment depends on symptoms and location
fat embolisms are most likely to occur from
long bone and pelvic fractures
Peripheral artery disease (PAD)
atherosclerosis of arteries that perfuse the limbs (especially lower); causes decrease perfusion to area
S&S PAD
pallor, pulselessness, hairlessness, intermittent claudication - pain occurs in legs while walking and gets better with rest
treatment for PAD
dangle legs
antiplatelet therapy
PAD vs PVD
PAD blood flow back to lower extremities is affected (cannot get to tissues); PVD blood flow back the heart is affected
coronary artery disease
occlusion of coronary arteries; most often resulting from atherosclerotic plaques
CAD can cause
MI, chronic stable angina (reversible)
chronic stable angina
caused by narrowing of arteries and plaque build up; periods of decrease blood flow to heart
decreased blood flow and O2 to heart leads to
ischemia
________ causes the chest pain in angina
ischemia
chronic stable angina the pain is
predictable and goes away with rest or nitro
treatment for chronic stable angina
nitro - open veins and arteries (dilation) -> decrease afterload -> increased CO
nitro doses
1 Q5 min x 3doses; no more than this unless bp being closely monitored because it can tank the bp
expected side effect of nitro and why
headache; b/c of massive dilation
unstable angina
does not go away with rest or nitro; reversible myocardial ischemia
if unstable angina is not treated quickly it will progress to
MI
MI
prolonged decrease blood flow to heart resulting in irreversible damage to the heart muscle; STEMI (more severe) or non-STEMI
MI S&S
crushing chest pain radiating to L arm or jaw or between shoulder blades, epigastric discomfort, fatigue, SOB, vomiting, elevated trops
women and elderly more likely to have GI symptoms
MI tx
cath lab within 90min; in the mean time oxygen, nitro, thrombolytic (if appropriate), antiplatelets (aspirin), monitoring, EKG to assess heart activity
MONA correct order
oxygen (only if sats low)
nitro
morphine (pain and decrease workload of heart limiting ischemic damage), aspirin (decrease chance of forming clots)
Pericarditis
inflammation of pericardium; caused by infection, tumor, drugs
pericarditis S&S and Tx
sharp chest pain, tachypnea, fever, chill, weakness
tx: NSAIDs
pericardial effusion
collection of fluid in pericardial sac; impairs cardiac function if severe and can lead to obstructive cardiogenic shock
pericardial effusion S&S and tx
chest pain, MUFFLED HEART SOUNDS
tx: pericariocentesis
cardiac tamponade
blood, fluid, or exudate has leaked into pericardial sac
cardiac tamponade S&S and tx
chest pain, SOB, decreased CO, muffle/distant heart sounds, JVD, narrowed pulse pressure (<40)
tx: pericardiocentesis and sx
cardiomyopathies
disease of myocardial tissue
types of cardiomyopathies
dilate - makes it harder for heart to pump blood to rest of body, wall of heart is too big and stretchy = poor contractility
restrictive - too stiff, cannot relax and fill with blood; decreased preload and CO
hypertrophic - wall too thick, poor contractility
S&S and tx of cardiomyopathies
both dependent on type and cause
stenosis of heart valves is the
narrowing
regurgitation of the heart valves is
them not closing properly causing backflow
endocarditis
infection and inflammation of endocardium; affects the valves
endocarditis can lead to and Tx
valve stenosis and regurgitation, poor CO, bacteremia , bacteria emboli
tx: abx
dysrhythmias are caused by
SA node generating abnormal rate and impulses not be conducted properly
Heart failure
the inability of the heart muscle to pump enough blood to meet the body’s needs for blood and oxygen
number one cause of HF is
htn
Left sided HF
cannot move blood forward to the body and is backing up in the lungs
Left sided HF S&S
dyspnea, cough, orthopnea, S3, pulmonary congestion, wet lung sounds, blood-tinged sputum, weakness, cyanosis, confusion
right sided HF
right side of heart cannot move blood forward to the lungs and backs up in the body
right sided HF S&S
ascites, weight gain, fatigue, anorexia, JVD, dependent edema, hepatomegaly, splenomegaly
HF treatment
decrease workload of the heart
ACE inhibitors, ARBs, digoxin, diuretics
