-
Antidysrythmics
- •ANTIDYSRYTHMIC AGENTS:
- •Dysrythmia- any disturbance or abnormality in the normal cardiac rhythm
- •Can be fast, slow, irregularly regular or regularly irregular
- •Frequent after MI, hypoxia- feels as a skipped beat
- •Most are very serious and require an anti-dysrhythmic agent
-
Medications
- •AGENTS:
- •CLASS I- membrane- stabilizers (Fast sodium channel blockers)
- •CLASS II- Beta-blockers
- •CLASS III- prolong repolarization
- •CLASS IV- Calcium channel blockers (Verapamil)
-
Definitions
- •Membrane Stabilizers- interferes with the sodium channels and stabilizes the hearts excitability
- •Beta blockers- blocks epi and norepi at the best
- adrenergic receptor sites (beta 1,2 and 3)
- •Prolonging repolarization- used for difficult to treat dysrythmias and conversion
- •Calcium channel blockers- decreases intracellular calcium = reduction of muscle contration
-
Class I’s
- •PROCANAMIDE- useful in atrial and ventricular tachy-dysrhythmias
- •Most effective in suppressing premature Vent contractions and preventing the recurrence of V tach.
- •Can cause lupus-like syndrome
- •Can cause n/v/d- anorexia
- •Can cause fever, leucopenia, maculopapular rash, itching, flushing
- •NOT used in clients with Lupus, complete heart block, 2nd
- and 3rd degree heart block
-
Class I
- •PROCANAMIDE- useful in atrial and ventricular tachy-dysrhythmias
- •Most effective in suppressing premature Vent contractions and preventing the recurrence of V tach.
- •Can cause lupus-like syndrome
- •Can cause n/v/d- anorexia
- •Can cause fever, leucopenia, maculopapular rash, itching, flushing
- •NOT used in clients with Lupus, complete heart block, 2nd
- and 3rd degree heart block
-
Quinidine
- •ACCELERATES RATE OF ELECTRICAL
- IMPULSES
- •Can cause loss of hearing, blurred vision, GI upset, tinitus, diarrhea, n/v and vertigo
- •Can cause thrombocytopenic pupura (TTP)
- -blood disorder that causes blood clots to form in small blood vessels around the body, and leads to a low platelet count.
- •Can cause decreased blood flow to the brain and death so TEST DOSES are given!!
- •Check potassium levels very closely- befroe, during and after…
- •Increased potassium = increased effects of the medication
- •And vice versa!
-
Norpace
- used primarily for treatment of Vent dysrythmias
- •Can cause anti-cholinergic side effects
- •Vent dysrythmias
- •Not used in clients with poor left vent function
- •Can cause hypotension and widened QRS intervals on EKG
- •Incidence of lupus is less than that of Procanamide
-
Class II
- Betablockers: selective (1) and nonselective (1&2)
- •Blocks (or slows) the SNS stimulation to the heart-
- • REDUCES THE HEART RATE and force contraction
- •Especially beneficial after an MI because many catecholamines are released at that time and can make the heart hyperirritable
- •25% reduction rate of cardiac death after an MI if on Class II’s
-
More on beta blockers
- •Blocking the beta cells (1, 2 & 3)
- •Beta adrenergic receptors- part of the SNS (fight or flight)
- •β1-adrenergic receptors are located mainly in the heart and in the kidneys
- •β2-adrenergic receptors are located mainly in the lungs, gastrointestinal tract, liver, uterus, vascular smooth muscle, and skeletal muscles
- •β3-adrenergic receptors are located in fat cells
- •MOST end in “lol”
- •There is a little hint to help…
- •Labetalol
- •Propanalol
- •Atenalol
- •Metoprolol
-
Propanalol
- •Used commonly for acute sinus tachy
- •So it will cause a decrease in heart rate which can = Bradycardia! Assess closely
- •Can also cause rash and itch
- •Erratic blood sugars up and down
- •Chest pain
- •Joint pain
-
Tenormin (Atenolol)
- Blocks beta-1’s on the heart
- •(Also used for angina and hypertension)
- •Contraindicated in clients with severe bradycardia, CHF and cardiogenic shock
-
Breviblock
- •shorter acting beta-blocker, Blocks beta 1’s
- •Used for SVT
- •And used for dysrythmias that originate above the ventricals and are fast
- •Can be used for tachyarrythmias that occur after an
- acute MI
- •Can be used to control hypertension
- •Not used for bradycardia or in clients with asthma
- •not used for those with 2nd or 3rd degree heart block or CHF
-
Lopressor (Metoprolol)
- •commonly given after an MI to reduce risk of cardiac death
- •Can be used for treatment of hypertension and angina
- •LOPRESSOR HCT- contains a hydrochlorathiazide diuretic
- •To diurese the patient, thus decreasing Bp – so assess what?
- •Selective- beta 1’s
- •Metoprolol is used for a number of conditions including: hypertension, angina, acute myocardial infarction, supraventricular tachycardia, ventricular tachycardia, congestive heart failure and prevention of migraine headaches
- •Causes hypotension, dizziness, blurred vision, etc.. Safety will be an issue at first
-
Inderal
- •is nonspecific (beta 1 and 2- works on receptors in the heart and lungs!)
- •Reduces heart rate
- •Reduces myocardial contractility
- •Oldest of this class of drug- many uses
- •Used for hypertension, angina
- •Used for VTach, supervent dysrhythmias, pheocromocytoma*
- •Used post MI, and for migraines
-
What is pheocromocytoma?
- •Adrenal gland tissue tumor
- •Results in the release of too much epinephrine and norepinephrine- controling heart rate, metabolism, and blood pressure
- •Common in early middle-adulthood
- •Rarely cancerous
- •Tremors, hypertension, tachy, weight loss, irritability and palpitations occur
-
Betapace
- •Used for the treatment of DOCUMENTED life-threatening
- vent dysrythmias such as sustained V tach!
- •Can cause new dysrhythmias
- •Not used for bronchial asthma clients, sinus brady or cardiogenic shock
-
Class III
- •Most commonly used to treat dysrhythmias that are difficult
- to treat
- •Used for the conversion of A-fib and flutter to a NSR
- •Still somewhat investigational
-
Amiodarone (pacerone)
- •used for life-threatening vtack or V-fib that is resistant to other drugs (Drug of last resort!)
- •Used also for the treatment of sustained V-tack
- •Recently studied- shown to effect atrial dysrhythmias that are resistant
- •Has a lot of unwanted s/e-
- •Containes IODINE in it’s structure (watch for allergies) therefore can cause hyper or hypo- thyroidism
- •Doses exceeding 400mg/D are more likely to see unwanted s/e’s
- •MOST common s/e- corneal microdeposits- causes halo’s, dry eyes and photophobia
- •Occurs in almost all adults on the med for 6 months or more
- •Is lipophilic- loves to migrate to adipose tissue
- •MOST serious s/e = PULMONARY TOXICITY- dyspnea and cough causing damage to the alveoli- can result in pulmonary fibrosis!
- •May also provoke new dysrhythmias
- •Has a long half-life- approaching DAYS!
- •May take several months after DC of the drug for s/e to discontinue
-
Bretylium
- •adrenergic blocking (slows release of norepi)
- •Slows conduction of ventricular portion of muscle
- •Only available IV
- •Used to treat life-threatening V-tach or fib
- •Used primarily in a code situation
- •Causes postural hypotension in 50% of patients
- •Can cause N/V
- •Given slow IV to reduce s/e
-
Covert
- •Indicated for ATRIAL dysrhythmias (A-fib and flutter)
- •ONLY drug therapy available for rapid conversion into NSR fro a-fib/flutter
- •Other way?- Electrocardioversion
- •Only IV and weight based
- •Other classes of antidysrhythmics should not be given if Corvert is being used, if so… give 4 hours apart
-
Class IV
- •Used as anti-dysrhythmics and for the treatment of hypertension and angina
- •(Calcium channel blockers)
- •Slows or blocks the calcium channels of the cell into the myocardium
-
Cardizem and Verapamil
- •CARDIZEM- Not used for MI, pulmonary congestion, severe hypotension, cardiogenic shock, sick-sinus syndrome, or 2nd/3rd degree heart block
- •VAREPAMIL (Calan)- Used to prevent and convert recurrent PSVT( paroxysmal SVT) and to control vent response in a-fib or flutter
- •Same contraindications as Cardizem
- •Precipitates with Nafcillin and Sodium Bicarb
- •Nitrates*- these are often taken WITH CCB’s
- •Be careful with the elderly- increased side effects- weakness and dizziness (safety)
- •Nicotene can decrease effectiveness
- •ETOH increases hypotensive episodes
- •Do not stop abruptly- can have a rebound effect!
-
Process: Assessment
- •Not used in: Hypersensitivity
- •CHF- can worsen effects of CHF
- •Complete heart block*
- •Hypotension
- •MG
- •Urinary retention
- •Hepatic/renal insufficiency
- •EKG/TELEMETRY
-
Drugs that interact with these meds:
- •NMBA’s
- •Anticholinergic’s- causes increased anti-cholinergic effects
- •Anticoags- with quinidine
- •Dig. and quinidine- increases serum dig levels
- •Cimetadine/Nefedipine
- •Anticonvulsants
-
Implementation
- •Initial EKG and VS- and monitor closely during
- •IV on a pump
- •If on Propanalol (Inderal)- report SOB or skin rash
- •VARAPAMIL (Calan) and beta blockers cannot be given together IV
- •Look for all other side effects as mentioned
- •SAFETY EDUCATION…
- •Any increased cough, SOB, weight gain- report..
- •ALSO: Lets talk about IV Lidocaine commonly used for
- ventricular dysrythmias
- •It increase the electricalimpulses and weak impulses are weeded out
- •SO it slows the heart rate overall
- •Assess tinitus, blurred vision, HA/dizziness, seizures, hallucinations…
- •Adenosine-
- •Given for cardioversion
- •Causes several seconds of asyystole when cardioverting tach to NSR
- •Causes anxiety!
- •Educate and be supportive
-
Anti-anginal medications
- •The ACHING of the heart muscle due to insufficient oxygen in the blood
- •Why?
- •Often idiopathic…
-
Types of angina
- •Chronic Stable Angina- caused by atherosclerosis
- •Can be triggered by exertion or stress (cold, fear,emotions)
- •Smoking, drugs, etoh, caffeine, coffee can exacerbate it
- •Intense pain that subsides in about 15 minutes
- •Unstable Angina (USA)- early stage of progressive CAD
- •May end in MI in sunsequent years
- •Pain increases in severity with each attack and attacks become more frequent
- •Can happen at rest when condition progresses
- •Vasospastic Angina- spasms of the smooth muscle layers that surround the atherosclerotic coronary arteries
- •Happens at rest usually
- •Seems to follow a regular pattern- occurring around the same time of day
- •Know the difference between the 3 types!
-
The drugs:
- NITRATES/NITRITES-most effective drug for CAD
- - Act on vascular smooth muscle- relaxes arterial and venous circulation
- BETA-BLOCKERS- as discussed earlier (review)
- CALCIUM CHANNEL BLOCKERS -also discussed earlier- (review)
-
1- Nitrates/Nitrites
- •NITROGLYCERIN: (Rapid acting)
- •Not used for those with ICP, inadequate cerebral perfusion, pericarditis, pericardial tamponade (fluid accumulation in the heart causing increased pressure), severe hypotension, and severe anemia
- •Orally- metabolized in the liver- a lot is removed from circulation (LARGE first-pass effect) therefore…
- •Usually given SL or Buccal so bypasses the first pass effect! Can be administered transdermally
- •Also given IV- for acute MI,CHF, and Pulmonary edema
- •Can be given topically- bypasses first pass effect- allows for slow delivery of the drug
- •Dilates all blood vessels, but mainly effect those in the venous circulation
- •Slight arterial dilation in low doses
- •Transdermal patches- usually OFF for 8 hours at night, new patch in the AM (review)
-
1-Nitrates/Nitrites
- •HA
- is most common- can be very severe
- •Tachycardia
- •Postural Hypotension- assess laying, sitting and standing and educate safety!
- •ETOH, phenothiazines, CCB’s- cause increased anti-hypertensive effects- again safety is an issue
- •½ life = 1-4 minutes- readily absorbed!
- •S/S of postural hypotension?- flushing, dizziness, sweating, syncope
- •Patients with acute MI? safety still being investigated, but…
- •A recent MI? transdermal patch is showing good performance
- •If nitrates taken with ETOH- severe hypotension
- •Same with beta blockers, narcotics, antihypertensives, and vasodilators
- •Tobacco reduces effects
- •Nitroglycerin increases VMA (vanillylmandelic acid) levels (end stage metabolite of epi and norepi)
-
SL Nitroglycerin
- •SL- under the tongue
- •Used for CP- ASAP
- •Educate to keep on their person at all times
- •CP? Lay down- take a dose…
- •If no relief in 3-5 minutes- redose (#2)
- •If no relief in 3 minutes- redose (#3)
- •Call 911!! (if at home)
-
ISOSORBIDE DINITRATE & ISOSORBIDE MONONITRATE
- •Isosorbide Dinitrate (Isordil)- Long acting
- •Metabolized in the liver
- •Used for acute angina and for the prophylaxis of…
- •Only PO
- •Iso Mononitrate- (Imdur, Ismo, Monoket)- Long acting
- •Provides a more steady, therapeutic response
- •Ismo and Monoket given 2X daily with 7 hours in between doses so as not to build a nitrate tolerance*
- •All available PO
-
2- Beta-blockers (again)
- •Beta-blockers- slows the heart rate and decreases contractility
- •1st line drug for stable angina and “effort induced angina”*
- •Decreases O2 demand, therefore increases O2 availability to the myocardium
- •Slows the contractility- decreasing energy needs
- •Fatigue and lethargy are common s/e’s r/t decreased Bp
- •PS- BB’s can increase Blood glucose in the DM pt.
-
2- Beta-blockers (again) Side effects
- •Hypotension- due to vasodilation- assess pulses can
- decrease peripheral blood flow!
- •Can also cause vasoconstriction- NOT recommended for COPD or asthma clients
- •Can cause bradycardia
- •Dizziness, fatigue, lethargy
- •Can cause impotence, wheezing, dyspnea
- •NOT USED if on anticholinergics, or on cimetadine, or on diuretics or phenothiazines
-
Tenormin and Lopressor
- ATENALOL (Tenormin)- often used after an MI to decrease death rate
- •Available IV and PO
- •IV = Good immediately after an MI because blood flow to GI tract is poor and most are intubated
- •LOPRESSOR (Metoprolol)- Used to treat angina and used after MI
- •Available IV and PO
-
CCB’s
- •Decreases myocardial O2 demand by causing peripheral arterial vasodilation, reduces myocardial contractility
- (decreases pain) decreases Bp
- •High risk for causing peripheral edema
- •Safe with few contraindications
- •Usually a first line agent in the treatment of angina
- •CARDIZEM, TIAZAC- effective oral
- treatment of angina
- •Available IV also
- •NIFEDIPINE (Adalat/Procardia)
- •Once we had to puncture the liquid filled capsule and squeeze under the tongue!
- •Now they have decided that this increases the mortality rate
- •Only available IV*
- •VERAPAMIL (Calan)- We discussed that already!
-
CCB Side effects
- •Hypotension
- •Brady
- •heart failure
- •Constipation, nausea
- •Rash
- •Peripheral edema
- •Wheezing
-
CCB’s should not be used with:
- •Digoxin- can increase dig levels
- •H2 blockers- increases CCB level
- •Beta blockers- additive effects
- •Theophyline
- •Lithium
- •ETOH
- •Trycyclic antidepressants
- •Tobacco
-
Any peripheral vasodilator medications
- •Can be used for occlusive arterial disease (limited success)
- •Relaxes smooth muscle of peripheral arterial vessels increasing circulation to the extremities
- •What will you see?- swelling to the lower legs and feet and often ulcerations below the knees
- •Can be used to treat Raynaud’s disease (vasospasms and thrombophlebitis)
- •Viagra is also a vasodilator
- •Vasodilators cause hypotension, dizziness, post. Hypotension, HA, dysrythmias, sweating, tingling, but disappear after a few weeks of txt.
- * Some will contain “tartrazine”- can cause an allergic reaction with s/s like bronchial asthma
- •If allergic to ASA? Increased risk of allergy to tartrazine
-
Process for all of these meds:
- •O Assess and list all other drugs
- •Allergies?
- •Medical and surgical Hx
- •Caution with head injuries and pregnant/lactating women
- •VS, EKG, RESP status
- •Not used with liver/kidney disease if possible
-
Implementations
- •IV Nitro in a glass bottle only*
- •NO filters
- •Nitro- new Rx. Every 3 months- loses strength
- •Keep in a brown bottle- sunlight and light can decrease the effects of medication
- •No cotton in the bottle- decreases effectiveness
- •Take on an empty stomach po
- •Causes a throbbing headache- it is a potent medication!
- •Can take an analgesic for HA
- •Only stable for 96 hours
- •ALWAYS on a pump
- •Covered in aluminum foil or in a dark bottle and dark tubing
- •Not mixed IV with any other drugs
- •IV nitro- ICU monitoring
- •Report if blurred vision or dry mouth
- •Elderly- increased risk of hypotension
- •Watch for nitrate abuse- can cause sexual stimulation
- •Angina without relief- call 911
- •Taper these meds!
- •Take Bp before giving meds, check lytes
- •Decrease caffeine containing foods/drinks, cardiac diet and decrease sodium
-
Hypertension
- •Blood vessels decrease in elasticity secondary for hypertension
- •The heart has to work much harder
- •This causes stress on the heart muscle and vessels, veins and arteries
- •Hypertension needs to be identified and treated early in the game!
-
Bp review: slide 64
- •Blood Pressure:
- •NORMAL = <130S <85 D
- •Stage 1 = 140-159 90-99
- •Stage 2 = 160-179 100-109
- •Stage 3 =180-209 110-119
- •Stage 4 = > or = to 210 > or = to 120
- •Diastolic below 90 to decrease damage risks to kidneys, heart and brain!
-
Antihypertensives 1. Adrenergics What is an adrenergic?
- •Adrenergic receptors are the target of catacholamines like epi and norepi
- •There are receptor subtypes- Alph 1&2,Beta 1&2
- •They inhibit or block stimulation of epi/norepi
- •Decreases BP and heart rate
- •Can cause postural and post-exercise hypotension
- •Can be used to treat Migraines
- •Can be used for severe dysmennhorea and menopausal
- flushing
-
Side effects & Interactions
- •SIDE EFFECTS:
- •Dry mouth
- •Constipation
- •drowsiness, constipation
- •HA
- •Nausea
- Rash
- •Ortho hypotension
- •INTERACTIONS:
- •CNS depressants- ETOH, barbituarates, opioids
- •Epi and beta-blockers can increase effect, decreasing BP too much!
-
Alpha 1 -adrenergic blockers
- •Newest adrenergic blockers
- •Best safety profiles
- •Block alpha 1 receptors in the arteries
- •Only available po
-
Minipress
- •Dilates arterial and venous blood vessels
- •This decreases blood pressure
- •Can also relieve urinary symptoms with BPH
- •Can be used with cardiac glycocides and diuretics fro
- CHF
- •Can cause severe orthohypotension, but most will
- develop a tolerance after the first dose
- •Other meds: Cardura, flomax and hytrin
-
Regitine
- •Used for the treatment of estravasated epi, norepi and dopamine infusion sites
- •Also used to diagnose pheocromocytoma
- •How?
- - If pheocromocytoma is suspected: pt has HTN and an IV dose of Regitine is given- this will cause a decrease in Bp and diagnosis can be made
-
Alpha 2- adreneric receptor stimulators
- •Not typically a first line antihypertensive
- •HIGH incidence of severe orthostatic hypotension, fatigue and dizziness
- •This class will be used if all other classes fail
-
The drugs
- Clonidine- (Catapres) – decreases Bp and can also be used for opioid withdrawal
- •Clonidine- po, (topical and epidural)*- used for severe pain in cancer patients
- •Do not stop abruptly- causes “rebound hypertension” Methyldopa- antihypertensive drug of choice for pregnant
- pt. Why? Beta blockers decrease the SNS stimulation in the heart and decrease heart rate and Bp more so than this drug- so think fetus effects
-
ACE Inhibitors
- •ACE- Angiotensin-Converting Enzymes
- •They mediate extracellular volume and arterial vasoconstriction component of the Bp regulating system
- •They prevent Na+ and H2O reabsorption
- •So this in turn causes diuresis
- •They are the largest group of antihypertensives
- •Safefirst line agent to treat CHF and hypertension
- •So with the prevention of sodium and H2o reabsorption- there is a decrease in the blood volume and return to the heart which decrease the Bp.
- •Hyperkalemia is a risk though!
- •Monitor k+ levels, and educate about
- K+ in the diet!
-
Side effects
- •Fatigue, HA, mood changes, dizziness
- •Dry non-productive cough* that reverses if med stopped
- •Loss of taste
- •Anemia
- •Proteinuria
- •Rash and itching
- •Hyperkalemia
- •Not used in renal disease- can cause acute failure
-
OD and toxicity management (ACEI’s)
- •s/s = Severe hypotension
- •Give IVF’s to expand the volume and blood volume
- •HD may be required for OD of captopril and lisinopril
- •Do not give with ASA, NSAIDS, K+ sparing diuretics or K+ supplements
- •No lithium b/c it increases lithium levels
-
Captopril (Capoten)
- •Used commonly after an MI to reduce risk of heart failure
- •Has the shortest half-life of all ACEI’s
- •Good for patients in fragile state
- •Only available PO
-
Lisinopril (Zestril, Prinivil)
- •NOT used in pregnancy
- •Lisinopril is used alone or in combination for hypertension
- •Lisinopril is also used to improve survival after a heart attack.
- •Used to treat CHF
- •Low Na+ and low K+ diet suggested
-
Vasotec
- •Oral an IV preps
- •To be converted into an “active metabolite”- must have proper liver function
- •Improves survival rates of those post MI
-
Angiotensin II Receptor Blockers
- -A natural substance
- in the body that narrows blood vessels thus increasing Bp
- -So if there is an increase in the narrowing effort- Bp increases more so
- -The blockers relax the blood vessels to decrease Bp by decreasing the narrowing effect
- •These are fairly well tolerated and do not cause the cough!
- •Improves survival rates s/p MI
- •Used to treat CHF
- •Can be used cautiously with DM, and renal dysfunction in those that have shown a tolerance for the medication without
- side effects**
- •Can cause birth defects- not a great idea with pregnancy
-
Side effects
- •URI symptoms
- •Nasal congestion
- •Dizziness
- •Dyspnea
- •Diarrhea, heart burn
- •Back pain
- •HA and fatigue
- •OD/Toxicity- expand circulatory volume and support systems
- •Hyperkalemia
-
Interactions
- •Lithium- increases levels
- •Cimetadine, Rifampin, and Phenobarbitol reduce the effectiveness of Cozaar
- •Diflucan decreases the conversion of Cozaar into its active form
- •Report any side effects to physician
-
The drugs:
- •Cozaar/Hyzaar (Cozaar with HCT)- used for txt. Of hypertension and CHF
- •May have slightler lower mortality rates than seen with ACE inhibitors in CHF
- •No breast feeding- crosses into the milk
- •Diovan (Diovan HCT (with diuretic)
- •Can be used along with other anytihypertensives
-
Other good info about antihypertensives:
- •Many as you see- come with a diuretic in on preparation
- •These decrease extracellular fluid volumes so there is a decrease in preload which decreases the effort of the heart
- •Those that vasodilate- relax the smooth muscle of the heart and long-term constriction will cause major damage to
- heart, brain and kidneys!
- •Ever heard of Minoxidil or Rogaine?
- •PO- this decreases Bp
- •Topically it is used for hair growth, but can it cause hypotension? YES
- •Educate!
-
Nursing Process:
- •Assess liver and kidney function
- •Assess stress
- •Any PVD?
- •Any history or suspect of pheocromocytoma?
- •Use all cautiously with kiddos and elderly- they are more sensitive and the diuretics can cause an increased lyte imbalance
- •Watch K+
- •Can take some meds with OJ unless contraindicated
- •Eat K+ rich foods unless contraindicated
- •Avoid increased Na+ intake
- •Garlic can be taken to decrease Bp, but not with coumadin, NSAIDS, anti-platelets or ASA!
-
Implementation and education
- •Baseline vs and weight and then along the way
- •QD weights
- •I/O
- •Baseline EKG, telemetry
- •Wacth for syncope
- •Swelling in the feet, ankles, eyes
- •Assess CP and palpitations
- •Loose weight, avoid stress, exersice safely
- •Leg cramps? May be hypokalemia
- •Be wary of the OTC’s
- •Change positions slowly
- •No smoking or ETOH
- •Stay hydrated
- •Oral formulas with meals to decrease GI upset
- •Watch sodium intake
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