arize from big cells in red bone marrow called megakaryocyes that break apart releasing small amounts of cytoplasm into the circulation
which hormone controls the platelets?
T/F: platelets lack nuclei and are 1/2 the size of RBC's.
what are the three main functions of plasma?
transport nutrients, gases, and vitamins
regulate fluid and electrolyte balance
maintain favorable pH
what are the 3 proteins found in plasma?
albumins: maintain osmotic pressure (water and BP)
globulins: alpha and beta; transport lipids and fat soluble vitamins
gama; type of antibody
fibrinogen: blood coagulation
Waht are the 3 gases found in plasma?
what are the nutrients found in plasma?
what are the nonprotein nitrogenous substances found in plasma?
what are absorbed from the intestines or released as by-products from metabolism?
what is hemostasis?
stoppage of bleeding
what are the three ways in which hemostasis is accomplished? Which is the best line of defense?
blood vessel spasm (vasoconstriction/vasospasm)
platelet plug formation
blood coagulation (best line of defense)
what is a vasospasm?
cutting or breaking the vessel causes the smooth muscle to contract. Can completely close the ends of vessels
what is platelet plug formation?
platelets adhere to any rough surface of collagen in the connective tissue. They also adhere to each other forming a plug.
Whether or not a clot forms is dependent upon the balance of what two groups of factors?
clot formation: formation of fibrin; prothrombin and fibrinogen combine together to form fibrin which creates a mesh-like structure to collect blood cells and platelets
clinical reference: PTT (prothrombin time) OR INR: 2-3
What are the two types of blood clots?
thrombus: clot abnormally forming in the tissue
embolus: clot that forms and dislodges that is now being carried in the blood stream
what are the three main blood vessels?
What are the three tunics of the blood vessels?
tunica intima: inner lining of single layer of epithlial cells (capillaries)
tunica media: middle layer consisting mostly of smooth muscle
tunica adventitia: outer connective tissue layer or sheath
What are the three types of arteries?
elastic (large): many elastic layers in their walls; aorta
muscular (medium): walls made up of circularly smooth muscle; femoral
small arteries and arterioles: narrow lumina and thick muscular walls
What are the purpose of small veins?
drain the capillary beds and join other smaller vessels to unite and form venous plexuses.
what are the purpose of medium veins? What kind of valves do they have?
drain venous plexuses and accompany medium arteries.
venous valves; one way valves
what are large veins characterized by and what is one example?
wide bundles of longitudinal muscle and well developed tunica adventitia
superior vena cava
simple endothelial tubes arranged in beds that connect the arterial and venous system that allows for the exchange of materials with the interstitial fluid.
what is muscle contraction in the limbs that function with the valves to move blood flow to the heart?
what are the three phases of cardiac rehab?
phase I: inpatient (acute)
phase II: outpatient (exercise training)
phase III: outpatient (maintenance)
what are the goals of phase I cardiac rehab?
general mobility, ADL's
when might you see a swan ganz on a patient?
first 1-3 days after heart surgery
what are the lead placements for a heart monitor?
WHITE clouds over GREEN grass on the right
BLACK smoke over RED fire on the left
BROWN in the middle
what is a typical treatment session with a patient in phase I CCU?
dangle: 12-24 hrs post extubation
bed -> chair transfer after 12-24 hrs
in room mobility typically 48 hrs after
what would a typical treatment include for a patient in phase I step down unit?
continued general mobility, ADL's
light ther-ex; bed and sitting exercises
progressive gait training
progressing toward 3 MET goal for DC
is there evidence to support sternal precautions?
what are the sternal precautions?
no lifting, pushing or pulling > 10#
- heavy doors, pick up or transfer laundry, vacuum, sweep, weight bearing through UE for ambulation (RW)
no shoulder flexion past 90* or scapular adduction
-anything that would open up the chest; combing back of hair, arm of chair for sit -> stand's
what are the contraindications to mobility? (8)
symptomatic heart failure
moderate-severe aortic stenosis
acute symptomatic illness or fever
resting BP of >200/110 (either systolic or diastolic)
What do you look for to know when to stop a session with a cardiac patient? (10)
dizziness or confusion
pallor, cold sweat
failure of systolic BP to rise as exercise continues (unless on beta blockers)
hypertensive BP response
progressive fall in BP of 10-15 mm Hg
significant change in cardiac rhythm
what is phase II of cardiac rehab?
medically monitored exercise program initiated 1-4 weeks post DC from hospital for 3X week up to 3 months.
what is the formal exercise test given initally for phase II of cardiac rehab or given to deconditioned "normals"?
low-level discharge GXT (LL-GXT)
what do phase II cardiac rehab session include?
warm up on treadmill or bike
aerobic exercise on machines
what is phase III cardiac rehab designed to do?
maintain and/or reintergrate the patient to community and home exercise
what are the 5 great vessels that attach to the heart at the base?
superior vena cava: large vein that returns deoxygenated blood to the right atrium from above the heart and UE's.
inferior vena cava: large vein that return deoxygenated blood right atrium from the lower chest and below.
pulmonary artery: carries deoxygenated blood from the right ventricle to the lungs.
pulmonary veins: carry oxygenated blood from the left ventricle to the body through th aorta.
ascending aorta: sends head, neck, and UE's via the subclavian and carotid arteries.
descending aorta: carries blood to the lower body and visceral tissue
where is the sternocoastal side of the heart?
right atrium and ventricle
where is the diaphragmatic side of the heart?
left ventricle and small part of the right ventricle
where is the pulmonary surface of the heart?
mostly the left ventricle and cardiac notch area of the left lung
where is the apex of the heart?
tip of the left ventricle
where is the base of the heart?
posterior aspect of the heart form mostly by the left atrium and some by the right atrium.
what are the three layers of the heart and what is it surrounded by?
epicardium: outermost layer; location of coronary arteries
myocardium: thickest layer of muscle wall that is responsible for heart contraction that is damaged during a MI.
endocardium: inner most layer that lines the cardiac chambers and valves
The heart is surround by a double walled connective tissue sac called the pericardium that protects the heart from trauma and infection.
what are the chambers of the heart?
Atrium and ventricles
What do the atria do?
right: receives deoxygenated blood from the body through the vena cava and the coronaries. Pumps blood forward through the tricuspbid valve.
left: receives oxygenated blood from the valveless pulmonary veins. pumps blood forward through the mitral valve.
what do the ventricles do?
right: receives deoxygenated blood from the right atrium via tricuspid valve. pumps blood forward through the pulmonic valves to the lungs.
left: receives blood from the left atrium via the mitral valve that pumps blood forward through the aortic valve to the aorta to the systemic circulation.
what creates the sounds heard during a heart exam with the steth?
the closing of the valves
what are the two types of atrioventricular valves and where are they located?
tricuspid: 3 cusps; btw right atria and ventricle
mitral (bicuspid): 2 cusps; btw left atria and ventricle
what are the 2 types of semilunar valves and where are they located?
pulmonic: 3 cusps; btw the right ventricle and pulmonary artery
aortic: 3 cusps; btw the left ventricle and the aorta
what is the coronary circulation?
provided by the coronary arteries that originate from the aorta that are returned to the right atrium via the coronary veins.
what is the left main artery?
comes off the aorta and runs along the surface of the left atrium where it splits to become the left anterior descending artery and the left circumflex artery.
which artery is known to be the widow maker?
left anterior descending (LAD)
what does the LAD supply?
left ventricle, interventricular septum, right bundle branch, portion of the left bundle branch, and the area around the apex.
what does the circumflex artery supply?
left ventricle, posterior fascicle of the left bundle branch, and the left atrium.
what comes off the aorta and goes around the heart in the opposite direction of the circumflex artery, going across the right ventricle and underneath the heart to feed the inferior muscle of the left ventricle?
right coronary artery (RCA)
what cardiac reflex is produced by a group of mechanreceptors that are found within the walls of the heart, intrathoracic vessels and large arteries that is activated with pressure exceeds 60mmHg and causes vasodilation secondary to inhibition of the vasomotor centers?
what cardiac reflex responds to the need for increased depth and rate of ventilation that has receptors located on the carotid and aortic vessles that detect decreased O2 levels and respond to an increase of arterial CO2?
what are specialized cardiac muscle cells and fibers that that initiate elctrochemical impulses and conduct them rapidly through the heart?
cardiac conduction system
what does the cardiac conduction system do?
coordinates the cardiac cycle so that the atria contract together then ventricles contract together
what is the "lub-dub" sound heard?
lub: diastole (bottom #) ventricles resting while atria fill
dub: systole (top #) ventricles are contracting
sounds heard from closing of one way valves to prevent back flow.
what is the SA node?
located in the upper right corner of the right atrium
pacemaker of the heart
what is the AV node?
responsible for delaying the impulses that reach it, allowing the ventricles to fill completly as the atria contracts.
does not have a pacemaker, but the tissue around it does. (junctional tissue)
what is the bundle of his?
resumes the rapid conduction of the impulses throughout the ventricles that divide into the right and left branches
what are the purkenjie fibers?
network of nervous tissue that extends through the ventricles
what is elevated arterial blood pressure both for systole and diastole?
what is a type of arterioscleriosis that is caused by accumlation of fatty deposits in the inner layer of arteries?
what results from impaired left ventricular functioning and/or malfunction of the heart to pump enough blood to meet the bodys needs that is usually a type of CAD?
congestive heart failure (CHF)
what is CAD and what may it produce?
coronary artery disease
narrowing or blockage of coronary arteries
may produce ischemia and necrosis of myocardium. Difficulty with vasodilation and arteries cannot meet metabolic demands
what is irreversible damage of heart segment due to ischemia that can be caused by narrowing of the artery or atherosclerosis?
myocardial infarction MI
what is arrhythmia and what are the 3 types?
impaired electrical impulse formation or conduction
benign atrial fibrilation (a-fib)
malignant ventricular tachycardia and ventricular fibrillation (v-tach or v-fib)
what can a-fib cause?
HTN, CHF, CAD, pericarditis, cor pulmonale, rheumatic heart disease, drug use
what is claudication?
pain that is caused by lack of oxygen
what are the s/s of MI? (7)
severe chest pain
radiating chest pain in the jaw or down one or both arms
what are the s/s of a cardiac pathology? (10)
cyanosis of lips or nail beds
jugular vein distension
what is cardiac output?
amount of blood measured in liters (4-6 is normal) that is pumped out of the heart through the aorta each minute that should increase as exercise load increases
CO= HR x SV (stroke volume)
what is venous return?
amount of blood that comes from the veins to the right atrium each minute
what is the cardiac index?
amount of blood pumped out of the heart per minute per square meter of body mass
range of 2.5 to 4.2 liters/min/meter
what is the normal blood volume for adults?
7-8% of body weight
what is the stroke volume?
amount of blood ejected from the ventricles with each myocardial contraction that is influenced by preload, afterload, and contractility.
what is preload? What can it be affected by?
force required to stretch muscle to its pre contraction length
blood volume, posture, venous return, filling time, pressure elasticity of heart muscles.
what is afterload and what is it affected by?
force muscle contracts during ejection.
affected by BP in aorta, aortic stenosis, stiffness of myocardium, viscosity of blood
what is contractility?
changes in muscle performance not ascribed to length or load
what is the normal heart rate for children and adults?
what is brady and tachy cardia?
brady: slow HR below 60 consistantly
tachy: fast HR above 100 consistantly
what does a strong, regular heart beat mean?
adequate force and consistent beats
what does a weak heart beat mean?
poor force with contraction
what does an irregular heart beat mean?
inconsistency with regard to strength and beat of heart.
where can you take pulses? (7)
brachial (upper arm and cubital fossa)
dorsal pedal (1st and 2nd metatarsals)
posterior tibial (medial malleolus)
what is drop of systolic BP >20mmHg with positional changes with s/s of lightheadness, dizziness, and LOB
what is absence of pink, rosy color and may mean a decrease in O2?
with is excessive cool, clammy skin?
what is hematocrit? what does it identify? what are the s/s of high/low? what are the adult norms?
percentage of RBC in total blood volume
hydration, polycythemia, anemia
low- weak, chills, dyspnea
high- increase risk of thrombus
what is hemaglobin? what does it identify? What are the adult norms?
function to carry oxygen from lungs to the tissues
low- anemia, hemorrhage
high- polycthemia, dehydration
what does a high and low platelet count indicate? what is norm?
high: increased risk for thrombus
low: increased risk brsing and bleeding
what does a WBC tell you and what does an increased WBC typically secondary to? What are the norms?
identify: infection allergens, bone marrow integrity or degree of immunosupression