Exam 3- Cardiac, diuretics, anticoagulants, thrombolytics Flashcards

(111 cards)

1
Q

Flow of blood through the heart and

systemic v pulmonary circuit

A
inferior/sup vena cava
R atria
tricuspid valve
R ventricle
pulm semilunar valve
pulm trunk
pulm arteries
lungs
reoxygenated blood into heart via pulm veins
L atria
mitral valve
L ventricle
aortic semi-lunar valve
aorta
ascending aorta
body

pulmonary circuit- pulmonary arteries to veins (lungs)
systemic circuit- aorta-vena cava (body)

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2
Q

electrical stim pathway of heart

A

top to bottom

SA node, AV, apex, Purkinje fibers, ventricles (contraction starts at bottom)

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3
Q

primary pacemaker of heart- signal from atria to ventricles

A
stimulated by bradycardia (sympathetic ns)
function- depolarize
sinoatrial node (in uppr prt right atrium)

transfer signal via AV

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4
Q

beta 2 v beta 1 receptors

A

beta 1- stimulate AV node= inc heart contractility
can contribute to vent remodeling w/ pt that have heart failure

beta 2- stimulate sympth nervous system= bronchodilation

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5
Q

L v R sided heart failure

A

L- blood backs into pulm system, hypertrophy/ overstretched L ventricle= dec SV= dec CO
“congestive heart faliure” s/s hypoxia and trouble breathing

R- blood backs into venous system= inc p pulm arteries= pulm edema, jugular venous distention, ascites

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6
Q

alpha 1 receptors

A

cause vasoconstriction and sm musc contraction

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7
Q

s/s heart failure

A

dec cardiac output= fatigue, exercise intol
FVO- crackles (L HR), pulm edema, inc rr, SOB, distress dec o2
(R HR)- distended jugular veins, periph edema

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8
Q

systolic v diastolic HF (b/ left sided)

A

systolic- dec contractility- hF w/ reduced ejection fraction

diastolic- shortened filling/relaxation time- HF w/ preserved ejection fraction

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9
Q

classification of HF- AHA stage v NYHA functional

A

aha- structural- A-D *need to know ejection fraction to test structural changes
A= high fisk but no structural changes of s/s
B-=structural changes, no s/s
C= structural changes w/ prior or current s/s
D= changes and s/s at rest- need specialized interventions

functional- s/s I-IV (based on pt ability to function, and complete ADL)
I-asympt
II-symptom w/ mod exertion
III- sympt w/ minimal exertion
IV- symtom at rest
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10
Q

heart failure def + causes

A

dec tissue perfusion
abnormal heart function
cause- CAD, HTN

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11
Q

cardiac output

A
hr x stroke vol
min/mL
amnt blood pumped/min
normal 3-7 L/min
dec heart rate or sv= dec co
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12
Q

stroke vol

A

mL/contraction x # beats/min

dec sv=dec co

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13
Q

contractility

A

(inotropy) strength of muscular contraction of the heart
dec contractility = dec co
inc contractility= inc sv=inc co *till a certain point (if too stretch myosin fibers have no leverage)

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14
Q

preload- def and causes of inc/dec

A

amnt stretching of ventricular cardiac musc before a contraction begins
dependant on vol fluid in ven

heart failure= inc preload
inc vol= inc preload= inc contractility (until certain point)
dec vol= dec preload= dec stroke vol= dec contractility= dec co
ideal is btw 8-12

causes dec= hemorr shock, dehydration= dec contact btw actin and myosin fibers (too srunched)
inc= fluid overload= dec contact of fibers

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15
Q

ejection fraction

A

percent of blood in LV leaving w/ e/ contraction

dec contractility= dec EJ

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16
Q

afterload

A

resistance against which LV has to work to push blood into arteries
factors- SVR (p in arteries) can inc w/ vasoconstriction
inc svr= inc afterload (P)

inc svr + additional V fluid from heart failure (preload) w small valve opening = inc p/workload= L ventricular remodeling

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17
Q

purpose of measuring bp

A

tells us lvl resistance
diastolic- resting state
systolic= CO
MAP= afterload

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18
Q

pathway of hf

A

dec EF- dec contractility- dec CO- inc sympathetic activation- stimulation of beta 1 recep. (vasoconstriction, fluid retention)- inc hr and contractility- alpha 1 recep activation (inc pvr and inc afterload P)- inc myocardial workload- dec co- dec renal perfusion- inc renin secretion- inc angiotensin 1- angiotensin 2 (vasoconstriction, fluid retention and inc bp) *also cardiotoxic at high lvls can cause v remodeling
fluid retention bc- inc aldosterone (na and h2o retention- further inc preload- L HF-pulm edema and R HF- peripheral edema)

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19
Q

natrietic peptides

A

stimulated by hypertrophy LV

anp/bnp- natural diuretic/vasodil

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20
Q

goals of pharmacologic therapy in hf

A

improve QOL and dec mortality/morbidity

by inc contractility
dec afterload, elevations in preload, ventricular remodeling, peripheral (R) and pulm edema (L)

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21
Q

classes meds to trt hf

A
ace inhib
angiotensin recep neprilisyn inhib (ARNI)
cardiac glycosides
diuretics
beta blockers
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22
Q

ace inhib- types, action and indications

A

lisinopril, enalapril, captopril, benazepril
action- dec conversion from ang 1 to ang2= dec preload and afterload
indications- hf, htn, dec mortality and morbidity after MI, prevn diab nephropathy (dec p and therefore damage of glomerular basement mem)
need to take if EF < 50% or s/s HF bc can dec prel, afterload and vent remodeling while improving EF

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23
Q

ace inhib- containdications, pharmacokin

A

coindiated- preg/lactation, hypersen (angioedema), renal impairment
pharmacokin- Po, duration 24h, 100% renal elimination

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24
Q

ace inhib- ae

A

hypotension (dec ang2= dec ability vasoconstrict)
watch after 1st dose! and espec if FVD (dehydration)
persistant dry cough- if block converting enzyme= inc bradykinin= inc dry cough
angioedema- inc risk as inc bradykinin (swelling of throat, feeling fullness, something stuck in throat)
hyperkalemia- flip btw na and K, dec ang 2= dec aldosterone= dec fluid retention= inc K 3.5-5 can result in vent tachy- cardiac dysrhyth

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25
angiotensin II receptor blockers (ARBs)- types-action and indication
Valsartan, Losartan, Candesartan block effects ang 2 so same effect as ace just different chemical process (not acutally inhibit converting enzyme so no inc bradykinin) therefore no inc problems w/ dry cough and angioedema
26
angiotensin II receptor blockers (ARBs)- pharmacokin v ace i
valsartan- liver metab, majority excreted via feces losartan- extensive liver metab, excreted by kid as active metab candesartan- prodrug- excreted in urine and majority in feces ** more liver metab, less kidney excretion worry
27
relationship btw vasodil and afterload | and aldosterone and preload
inc vasodil= dec SVR= dec constriction= dec afterload (P) | dec aldosterone= dec fluid retention= dec preload
28
Angiotensin recept- Neprylisin inhib (ANRI)- type, action, indication
ARB (valsartan) combo w/ neprylisin inhib (sacubitril) Entresto neprylisin enzyme inactivates natrietic peptides (respon diuretic/vasodil) inhibiting enzyme will inc anp/bnp= inc diuresis= dec preload and vasodil= dec afterload preferred med if not taking anything to control HF if switching to this frm acei need to stop taking acei or arb for 36h or high risk for angioedema trial- improved HR s/s, dec hospitalizations and reduced mortality
29
nursing considerations for acei, ARB and ANRI
monitor bp (hypotension), incl orthostatic changes monitor angioedema (esp w/ acei or switching) monitor bun, cr, K+ renal bc acei fully excreted via kidneys, risk for hyperkal in acei pt education- change position slowly, avoid salt sub w/ acei (already high ris k for inc K due to dec aldosterone)
30
cardiac glycosides (Digoxin)- action, indication
trt a-fib and control hr action- inc contractility by inc Ca into musc cells= stronger contraction and enhance parasympath ns (vagal influences)= dec onduction via AV node frm artrial to ven= dec hr aka "rate ventricular contracting"
31
cardiac glycosides (Digoxin)- containd, route, pharmacokin
contraind- av heart block (rhythm abnormality delays conduction thru AV) so adding digoxin can exacerbate block WPW- abnorm conduction pathway otherthan AV, so if shut off main pathway can overstim alt pathways hypokalemia renal impairment, acute MI (inc contractility= inc o2 demand= ae of MI) trt MI before admin route- Po or IV pharmacokin- unchanged by kid
32
cardiac glycosides (Digoxin)-ae and inc risk
ae- bradycardia** n/v, anorexia, abdom discomfort earliest s/s blurred vision, green/yellow aura (halo arnd lights) inc risk w/- hypokalemia (K and med compete for same cardiac cell recep so if K is depelted med has more room to be activated and therefore cause toxicity) extremes in age (inc sensitivity) use loading doses give inc dose so drug reaches theraputic range faster but can overshoot this and cause toxicity) hypoxia (inc contract= inc o2 demand) impaired renal function
33
cardiac glycosides (Digoxin)- nursing considerations
monitor apical pulse 1 min- hold if <60 continuous EKG for IV admin assess therapeutic effect (should hold hr and stop afib) geriatric consdier (ink risk falls if bradycardia bc dec sv=dec co= dec perfusion= syncope) monitor labs (cr, bun, gfr, K+) pt ed- how assess own pulse hold med if <60 s/s dig toxicity (GI, visual changes, bradycardia)
34
test for pt w/ possible digoxin toxicity
K, bun, cr, gfr labs akg continuous heart monitor if comes back positive- dig lab lvl hold med k supplement temporary pacemaker (external transcut or transvenous)
35
types diuretics
loop thiazide aldosterone antagonists
36
loop diuretics- types, moa, indication
bumetanide (Bumex) po oriv furosemide (lasix) po/iv *can dev resistance torsemide (Demadex) iv only moa- act on ascending loop to dec na and h20 resorption= inc excretion indications- edema, s/s HF (dec vol= dec P on vessles= dec afterload), renal dis, hepatic cirrhosis, HTN
37
loop diuretics- pharmacokin, ae
absorbed in GI tract onset po- 1h, IV 5-10 min ae- electrolyte depletion (K) s/s- weakness, dizziness, leg crmps, vomiting, confusion, dysrthmias need K replacement -always check! Gi disturb- diarrh, anorexia, stomach pain/cramping hypotension- hold if <100 ototoxicity w/ IV admin if push too fast! impaired glucose tol (might need inc insulin) FVD or s/s overdiuresis- dry muc mem, dec urine output reflected in labs- dec blood vol= dec LV supply= dec preload= dec sv= dec co= dec kidney function =inc Cr, BUN, gfr (rapid)
38
loop diuretics- interactions
digoxin- toxicity/ hypokalcemia corticosteroids- hyperglycemia and hypokalemia warfarin- inc anticoag effect inc hypotension w/ o/ antihtn meds aminoglycoside antib "gentamicin"- ototoxicity
39
thiazide diuretic- type, moa, indication
hydrochlorthiazide (HCTZ) moa- block na and cl reabsorption in distal tubule indications- htn, edema-HF, renal dis, cirrhosis, corticosteroids, estrogen therapy
40
thiazide diuretic- pharmacokin and contraindications
pharm- po, excreted unchanged by kidneys | contraind- allergy to sulfonamides. impaired renal function, lactation, pregnancy (jaundice/thrombocytopenia)
41
thiazide diuretic- ae and interactions
ae- hypokalemia, hypotension, inc uric acid (gout), hyperglycemia, gi (n/v, constipation), hepatitis (liver inflamm), pancreatitis interactions- inc hypotension w/ o/ anti htn corticosteroids- hyperglycemia, inc excretion k (hypokalemia) digoxin- toxicity and hypokalemia *similar to loop diuretics
42
aldosterone antagonist- type, action, indication
K+ sparing (dec aldosterone = inc K) "Spironolactone" (Aldactone) action- inhib aldosterone dec h2o and na resorption, inc K indication- excess fluid assoc w/ HF and hepatic cirrohsis can inc survival in pt w/ mod-severe HF
43
aldosterone antagonist- ae and interactions/ contraindicated
ae- hyperkalemia, skin rash, gi disturb, dizziness, sex hormone abnormalities (menstrual and gynecomastia) interactions- caution w/ acei (inc risk hyperkalemia) anticoag inc risk bleeding digoxin- med can inc dig accum= inc risk toxicity
44
general diuretic considerations and pt ed
``` admin in am and early evening- prevent falls admin iV slowly 20mg/mL po diur w/ food dec gi monitor bp, hold if <100 weigh daily, I&Os labs- cr, bun, gfr, K bg's fluid imbalance (excess or deficiet) pt ed- older women don't take cause can cause incontin K+ supplements and s/s hypokalemia low sodium diet (no salt sub w/aci bc risk hyperkalemia) postural hyptension ```
45
structural effects hf meds- all types
``` acei / ARBs- dec afterl and prel, dec vent remodeling ANRI (neprilisyn inhib)- dec afterl and prel, dec vent remodeling cardiac glycosides (digoxin)- inc contactility diuretics- dec prel, afterl, and edema (pulm and peripheral) beta blockers- dec afterl, dec SNS stim of heart, dec vent remodeling ```
46
Virchow's triad- purpose
factors involved in increased clotting risk
47
Virchow's triad- genetic/ aquired
genetic- prothrombin deficiency, alteration in clotting cascade ``` aquired- inflamm response (inc platelet or rbc) Chronic hypoxemia (COPD), stimulation of erythropoietin (Polycythemia) Can vary w/ geographic areas (elevation changes) ```
48
Virchow's triad- 3 causes
Damage to endothelium IVs, fractures, dislocations, CVD (atherosclerotic changes) Blood stasis Surgery, decreased mobility, atrial fibrillation Venous (DVT/PE) Hypercoagulability Dehydration (inc viscosity), hematological disorders Drugs- ex. Oral contraceptive
49
anticoag action
prevent clot formation and extension | Taken after surgery
50
antiplatlet action- venous v arterial
``` interfere with platelet activity Venous v arterial clots V- DVT d/t venostasis Composed of clumped RBC A- caused by platelet aggregation (atherosclerotic changes) CAD Dec ratio of RBC ```
51
thrombolytic agent action
dissolve existing thrombi | clot lysis
52
anticaog- types
heparin (UFH) low molecular weight heparin enoxaparin (lovenox)- parental oral- zarelto and warfarin (coumadin)
53
intrinsic pathway
contact activation monitors heparin labs- PTT thrombin
54
extrinsic pathway
act. w/ tissue damage warfarin monitor PT/INR prothrombin
55
role thrombin
converts fibrinogen to fibrin (end stage clot dev) heparin inhib thrombin warfarin inhib prothrombin (step before)
56
PTT lab
intrinsic (heparin) | range- 1.5-2.5 times baseline
57
heparin assay
same as PTT but more expensive | range- 0.3-0.7
58
PT/INR
extrinsic (warfarin) range- 2-3 sec commonly 2.5-3.5 for mitral mechanical valves
59
PT/INR, heparin assay/ PTT needed in?
anticoag | not applicable if admin anti-thrombotics!!
60
short-acting parenteral anticoag- types
heparin and LMWH (Lovenox/ enoxaparin)
61
heparin- action and indications
``` Actions Potentiates the action of antithrombin Inhibits factor Xa Prevents formation of thrombin Blocks thrombin activity (converting fibrinogen to fibrin) Inhib intrinsic or common pathway ``` Indications Prevention and management of thromboembolic disorders Ex: DVT, PE, Atrial fibrillation, MI, CVA Maintain patency of IV catheters
62
heparin- route
IV drip- for therapeutic trtment (PE) SubQ- prophylactic (given q8/ 12 depending on risk) Not Po (cannot cross GI mem., lrg molecular size)
63
heparin- pharmacokin
metab- liver, elim- some renal, most endothelial cells * no predictable action after subq subq peak- 2h, duration8-12h IV peak- 5-10 min, duration 2-6h
64
heparin-- IV admin
used as therapeutic trtmnt | dosed as bolus w/ continuous IV (weight based)
65
heparin IV considerations
Monitor PTT (partial thromboplastin time) Therapeutic range 1.5-2.5 Xs baseline or level determined by specific lab (varies w/ facility) Normal PTT 25-35 Ex. Normal therapeutic range- 1.5*25 and 2.5*35= (37.5- 87.5) Alternative: Monitor heparin assay (Anti-Factor Xa Level)—goal 0.3-0.7 Benefit- less variable btw individ.
66
heparin subq admin and considerations
abdomen only, dec risk bleeding, less mvmnt): SubQ route effective for prophylaxis only Dosed 5000 units SubQ every 8-12 hours Never given IM (inc risk bleeding bc high vascularity)
67
most severe bleeding site v most common
common- GI | severe-cranial
68
protamine- def, indication
heparin antagonist | indication- GI, cranial bleed or neuro compromise
69
protamine- route, goal, considerations
loading dose + infusion (drip) (roughly 1mg of Protamine neutralizes 100 units of heparin activity) goal- return clotting factor levels to baseline keep in mind heparin activity w/in last hr 800u/hr- give 8mg/ hr of protamine PTT should be used to monitor the effect of protamine in neutralizing heparin
70
protamine- ae
flushing, nausea, vomiting, dyspnea
71
lovenox (LMWH)- action, indication, and route
Action: inhibits factor Xa Indications: Prevention and treatment of VTE (DVT, PE) MI Unlabelled use: systemic anticoagulation for other diagnoses Route: SubQ (abdomen only)
72
Lovenox- pharmacokin
metab- liver elim- kidneys (clearance dec by 30% w/ renal impairment) ei- do not give w/ severe renal fun no need for IV drip duration 12h
73
lovenox- dosing- prophylaxis v therapeutic
prophylaxis- for VTE (30-40mg every 12h) therapeutic- MI, Afib, VTE (1 mg/kg every 12h)
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heparin v enoxaparin- contraindications
``` Hypersensitivity Active, major bleeding GI ulcerations Intracranial bleeding Dissecting aortic aneurysm Recent eye/brain/spinal cord surgery Severe thrombocytopenia (low platelet count) Hemorrhagic CVA ```
75
heparin v enoxaparin- caution in
Uncontrolled HTN (inc p cerebral arteries, risk hemorr) Severe liver or kidney dysfunction (drug accum wl LMWH) Last trimester of pregnancy or immediate post-partum period (inc risk bleeding) Spinal/epidural anesthesia or lumbar puncture (have bleeding at site= blood accum in epidural space, inc p on spinal c= permeant paralysis) Hold anticoag 24h after dc anticoag
76
heparin v enoxaparin- ae
BLEEDING Hematoma, bruising Differentiate by palpation Hematoma= hard Bruise= soft Thrombocytopenia Heparin induced (HIT) – allergic rxn Heparin causes inapprop act platelets (too much clotting) Inc clotting- dec platelets (use platelets faster than can produce) Presents w/ drop 50% platelets after admin heparin Mre common in heparin (UFH)
77
enoxaparin- nursing considerations
Double check doses Assess for bleeding Petechiae, excessive bruises, drop in bp, inc hr, pale, cool skin color, dec urine output (dec renal perfusion), weak pulses, I+O’s, LOC, severe headache (hemorr stroke) Assess for hypersensitivity (fever, chills, urticaria, hives) Monitor H/H, platelets SubQ route: rotate sites, assess for hematomas
78
IV heparin- considerations
Monitor aPTT or heparin assay to regulate therapy, double check compatibility with other IV solutions For significant bleeding: Hold heparin—short half-life when given IV Consider Protamine or FFP (fresh, frozen plasma- replacing clotting factors) administration, if necessary
79
heparin v enoxaparin- disadvantages
hep- Short duration of action Need for continuous IV gtt for full anticoagulation Frequent lab draws (PTT, HA) Inc risk HIT enox- Longer duration of action More accumulation with renal dysfunction
80
heparin v enox- advantages
hep- Effective anti-coagulation with IV gtt Short duration of action- better for pre-procedure Stop 1-2h before enox- Does not require monitoring of blood *******coagulation tests SubQ route can be used for full-dose therapy Can be used for outpatient anticoagulant therapy Less thrombocytopenia Longer duration of action (12h)
81
direct acting oral anticoagulants- pros v cons
pros- predictable response (not need regular lab testing) low incidence brain bleeds cons- more expensive, inc risk bleeding GI tract
82
DOAC's- zarelto or eliquis-action and indication
oral version enoxaparin inhib factor Xa indication- preve/trtmnt VTE, prev. embolic CVA in afib
83
DOAC's- Pradaxa- action and indication
action- inhib thrombin (converting factor for prothrom to fibrin) use- Prevention of embolic CVA in nonvalvular afib Prevention/treatment of DVT/PE
84
long acting anticoag
warfarin (coumadin)
85
warfarin- action and indication
Action: Acts in the liver to prevent synthesis of vitamin K-dependent clotting factors (II, VII, IX, and X) **Not inhib existing factors- instead inhibits synthesis of factors in the liver Vitamin K antagonist Indications Prophylaxis and treatment of: Oral meds for full anticoag therapeutic trtment (not a prophylaxis) VTE (DVT/PE) Afib with embolization Management of MI Prevention of thrombus formation and embolization after prosthetic valve
86
warfarin- route, pharmacokin
``` Route: Oral Pharmacokinetics: Well-absorbed from GI tract Metabolized by liver, excreted by kidneys Half-life 42 hrs DD and food interactions ```
87
warfarin- dosing
start w/ 5mg *overlap w/ heparin (or LMWH) by 4-5 days till drug kicks in monitor w/ INR (PT) daily until therap goal achieved, then 1-4 weeks
88
warfarin- therap INR goal
VTE, afib, MI, aortic mech valve- 2.0-3.0 | mitral mech valve- 2.5-3.5
89
INR therap window- low v high
low- thromboemoblic = progression of clot high- INR of 4, hemorrh complications (brain bleed, GI, hemorr shock)
90
warfarin- ae and considerations
ae- bleeding ``` Monitor for/prevent bleeding Monitor INR Patient education Consistent dietary intake of vitamin K No alcohol Bleeding precautions Follow-up lab work Drug/food interactions Foods high K- leafy green veg, in moderation, consistent w/ intake certain foods Drugs- high risk interactions, notify provider if add new vitamin or OTC ```
91
relationship btw vitamin K and INR in warfarin
Inc vitamin K= dec INR= inc risk overclotting Dec K= inc INR= inc risk bleeding
92
Warfarin drug/food interactions
Drugs- inhibit (dec effect) anti-infectives (nafcillin), cardiovasc (cholestyramine), CNS (barbiturates) Drugs- potentiation (inc effect, cause excess anticoag) Anti-infectives (ciprofloxacin, erythromyacin) cardiovasc (fenofibrate, propranolol), CNS (alcohol, sertraline) *no indivi vitamin supplements supplements- ginseng, ginko, garlic suppl Liquids- cranberry juice, alcohol Foods- green leafy vegetables Kale, spinach, greens, collards, parsley, broccoli (all can be bad if cooked too)
93
warfarin- antagonist- vitamin K and FFP
``` Vitamin K Used in less severe bleeding Takes around 24 hours to reverse INR Subq or IM Clotting factors have v different half lifes- prolonged time to see change ``` Fresh frozen plasma (FFP) Immediately replaces clotting factors (warfarin not inactive. Existing Clotting factors, only synthesis in liver)
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platelet lifecycle
sub endoth. Exposure, act. Platelet adhesion and later aggregation- forms platelet plug
95
risk for endothelial damage- atherosclerosis and PCI
HTN, Diabetes, Hyperlipidemia, smoking CAD-MI Cerebrovascular dis, carotid artery plaque- cva (ischemic) S/P PCI (percutaneous coronary intervention) cath goes into artery and balloon expands w/ metal splice
96
antiplatelet- aspirin patho
inhib cyclooxygenase, dec production A2- dec expression GP receptor
97
antiplatelet- plavix patho
Plavix- blocks ADP recep, prevent stimuli of GP receptor
98
role of GP receptor
causes platelet aggregation | inhib by aspirin and plavix
99
aspirin- action, indication and dosing
``` Action MI prophylaxis Prevents thrombus formation by preventing the production of thromboxane A (TXA2), a prostaglandin that causes platelets to aggregate. Aspirin irreversibly inhibits cyclooxygenase, which synthesizes TXA2, in the platelet. Indications MI prophylaxis Ischemia CVA/TIA prophylaxis Dosing 81-325 mg po daily ```
100
aspirin- ae and interactions
``` ae-Nausea, vomiting GI upset Heartburn (take with food) Bleeding (easy bruising, gum bleeding) Tinnitus Thrombocytopenia ``` interactions- Oral anticoagulants, heparins Steroids, alcohol, NSAIDS
101
clopidogrel (plavix)- action and indication
Mechanism of Action: Irreversibly inhibits platelet aggregation by blocking ADP receptors on platelets, preventing platelet aggregation Indications: Prophylaxis against thrombotic events in patients with recent MI, recent stroke Prophylaxis against thrombotic events s/p stent (super aspirin, stronger action) Use w/ coronary stents (PCI)
102
clopidogrel- dosing, ae, interactions
Dosing Recent MI or stroke: 75mg daily Acute coronary syndrome/stent: 600mg po x 1 then 75mg daily with aspirin Adverse effects Minor bleeding, headache, dizziness Rash, abdominal pain, hypertension, edema Thrombocytopenia Dec platelets= exacerbate clotting factors Interactions Increased risk of bleeding with NSAID, warfarin PPIs may decrease effectiveness
103
thrombolytics- first gen
streptokinase, urokinase
104
thrombolytics- second gen
tPA
105
thrombolytics- third gen
reteplase, TNKase
106
thrombolytics- action, dosing and indications
``` Action—breaks down fibrin clot lysis Dosing IV Based on patient’s weight or fixed dosing (depending on drug and indication); not to exceed maximum doses for particular agents Immediate onset Indications Myocardial infarction CVA (ischemic ONLY) Pulmonary embolism (not systemic, only at specific site) Deep vein thrombosis Arterial thrombosis Occluded intravenous catheter temporary treatment ```
107
thrombolytics- ae
Cardiac arrhythmias (good sign, indicates perfusion) with coronary reperfusion; hypotension BLEEDING, especially watch for: INTRACRANIAL HEMORRHAGE, GI/GU BLEEDING. Most common sites of bleeding—venipunctures Urticaria, nausea, vomiting, fever Anaphylaxis, especially with Streptokinase (first gen)
108
thrombolytics- absolute contraindications
Intracranial hemorrhage (ICH) on CT or history of ICH Suspected subarachnoid hemorrhage Uncontrolled HTN (SBP> 185, DBP>110) (inc risk intracranial hemorrhage) Neurologic surgery, serious head trauma or previous stroke in previous 3 months. (area brain damaged frm prev stoke has inc risk for bleeding) Seizure at stroke onset Arteriovenous malformation (AVM), neoplasm, or aneurysm Suspected/confirmed endocarditis (risk bleeding brain) Known bleeding risk (thrombocytopenia, receiving anticoagulants, prolonged bleeding times) BG <50 or >400 (need to be able to determine what change in mentation is from)
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thrombolytics- considerations (labs)
Only administered in critical care settings: ED, ICU, cath lab Assess bleeding times prior to administration (PTT, INR, platelet count, fibrinogen). Fibrinogen is assessed 2-3 hrs after start of therapy to check for fibrinolysis.
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thrombolytics- considerations (time constraints)
Begin therapy ASAP after onset of symptoms Time windows (time after which the risk outweighs benefit): STEMI—within 12 hours (MI w/ ST elevation) Permanent damage heart occurs after 12 h Ischemic CVA—within 4.5 hours (previously 3)
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thrombolytics- considerations (assessment)
Assessment: VS—continuously Assess pt carefully for bleeding every 15 min during 1st hr of therapy Neuro changes (H/A, decreased LOC) GI bleeding- Abdominal pain with coffee-ground emesis or black, tarry stools GU bleeding- Hematuria Avoid invasive procedures (IM injections, arterial punctures). If punctures necessary, hold pressure for at least 30 min after. Start 2 IVs prior to initiating infusion