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72 Cards in this Set
- Front
- Back
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Briefly discuss the sympathetic nervous system in relation to drug therapy—specifically, the effects of adrenergic stimulation or sympathomimetic effects.
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Ch 17
Catecholamines are substances that produce a sympathomi-metic response (stimulate the SNS). The naturally occurring or endogenous catecholamines include epinephrine, norepineph-rine, and dopamine. An example of an exogenous catecholamine is dobutamine. These are referred to as adrenergic receptors, and these are the sites at which adrenergic drugs bind and produce their effects. Dopaminergic re-ceptor-when stimulated by dopamine, these receptors cause the vessels of the renal, mesenteric, coronary, and cerebral arteries to dilate, which increases blood flow to these tissue. |
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List the various drugs classified as adrenergic agonists or sympathomimetics.
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Ch 17
Adrenergics Drugs that stimulate the sympathetic nervous system. They are also referred to as adrenergic agonists or sympathomimetics because they mimic the effects of the sym-pathetic neurotransmitters norepinephrine and epinephrine. Catecholamine drugs A direct-acting sympathomimetic binds directly to the receptor and causes a physiologic response. Epinephrine is an example of such a drug. An indirect-acting sympathomimetic is an adrenergic drug that, when given, causes the release of the cate-cholamine from the storage sites (vesicles) in the nerve endings, which then binds to the receptors and causes a physiologic re-sponse. Amphetamine and other related anorexiants are examples of such drugs. A mixed-acting sympathomimetic both directly stimulates the receptor by binding to it and indirectly stimulates the receptor by causing the release of the neurotransmit-ter stored in vesicles at the nerve endings. Ephedrine is an example of a mixed-acting adrenergic drug. |
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What is terbutaline*?
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B-adrenergic agonist
(Brethine, Brethaire, Bricanyl) used to stop labor Activation of B2-adrenergic receptors produces relaxation of he bronchi (bronchodialation) and uterus, also causes increased glycogenolysis in the liver and increases in renin secretion in the kidneys. |
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What are adrenergic blockers?
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they have the opposite effect of adrenergic drugs
also know as Adrenergic antagonists Sympatholytics - lyse or breakdown Sympetholytics inhibit - or LYSE - sympathetic stimulation Classified by the type of adrenergic receptor they block |
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List the drugs that are cholinergic blockers
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Anticholinergic:
Atropine Increased HR, (3D effects) Drying, decreased motility GI & GU, Dilated pupils |
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Discuss the mechanisms of action, drug effectsand indications of cholinergic-blocking drugs.
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Ch 17
Mechanism of Action: Competitive antagonists, compete with ACh, Block ACh at the muscarinic receptors in the PSNS, As a result, ACh is unable to bind to the receptor site and cause a cholinergic effect, Once thes drugs bid to receptors, they inhibit nerve transmission at these receptors Drug effects: Cardivascular: small doses; decrease heart rate, large doses increase heart rate CNS: small doses; decrease muscle rigidity and tremors, Large doses: drowsiness, disorientation, hallucinations Eye: dilated pupils(mydriasis), decreased accommodation due to paralysis of ciliary muscles GI: relax smooth muscle tone of GI track, decrease intestinal and gastric secretions, decrease motility and peristalsis Genitourinary:*relaxed detrusor muscle, Increased constriction of internal sphincter, *Result: urinary retention Indications: CNS- parkinson's disease, drug-induced extrapyramidal reactions, decreased muscle rigidity and muscle tremors |
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Differentiate between the following terms: inotropic, chronotropic, and dromotropic
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Chronotropic drugs Drugs that infl uence the rate of the heartbeat. Positive chronotropic drugs increase the heart rate, whereas negative chronotropic drugs decrease it.
Inotropic drugs Drugs that infl uence the force or energy of muscular contractions, particularly contraction of the heart muscle. Positive inotropic drugs increase myocardial contrac-tility. Dromotropic drugs Drugs that infl uence the conduction of electrical impulses. Positive dromotropic drugs enhance the conduction of electrical impulses in the heart. |
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State the mechanisms of action, indications,drug effects, adverse effects of cardiac glycosides.
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Mechanisms of action: Increased myocardial contracitility; decrease rate of electrical conduction; prolong the refractory period; area between SA node and AVnode; Result: reduced heart rate and improved cardiac efficiency.
Indications: Heart failure, Supraventricular dysrhythmias, Atrial fibrillation and atrial flutter Drug effects:Postivibe inotropic effect-increase contraction-Negative chronotropic effect-reduced heart rate-negative dromotropic effect-decreases automaticity of SA node-Heart failure Adverse effects- Very narrow therapeutic window, drug levels must be monitored, low potassium levels increase its toxicity, electrolyte levels must be monitored |
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Identify significant drug, laboratory test, and food interactions associated with cardiac glycosides and other positive inotropic drugs.
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Significant drug: Digoxin
Lab tests: potassium, sodium, magnesium, calcium, renal and liver function studies. food interactions: avoid giving digoxin with high-fiber foods (fiber binds with digitalis) |
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Define the term dysrhythmia and explain its causes and consequences for the patient.
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any deviation from the normal rhythm of the heart.
a dysfunctional heart rhythm the therm arrhythmia literally means no thythm or absence of heartbeat yet it is still used |
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Identify the most commonly encountered dysrhythmias.
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Ventricular dysrhythmias
Supraventricular dysrhythmias |
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Compare the various dysrhythmias with regard to their basic characteristics, the impact on the structures of the heart, and related symptoms.
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Ventricular dysrhythmias- most serious, where most of the heart action occurs, a greater number of electrical impulses than usual may arrive in the ventricle before the refractory period is over.
Supraventricular dysrhythmias- the top aspects of the heart (the atria) may be contracting several hundred times a minute. |
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Define hypertension, with comparison of primary and secondary hypertension and their related manifestations
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hypertension is defined as high blood pressure. Range is considered normal at 120/80. 121 - 139/81 - 89 is considered prehypertensive. Stage 1 begins at 140 - 159/80-89, Stage 2 begins at 160/100.
Hypertension can also be defined by its cause. When the specific cause of hypertension is unknown, it may be called essential, idiopathic, or primary hypertension. About 90% of the cases of hypertension are of this type. Secondary hypertension makes up the other 10%. Secondary hypertension is most commonly the result of another disease such as pheochromocytoma (adrenal tumor), preeclampsia of pregnancy (a pregnancy complication involving acute hypertension, among other symptoms), or renal artery disease. It may also result from the use of certain medications. If the cause of secondary hypertension can be eliminated, blood pressure usually returns to normal. |
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Discuss the normal anatomy, physiology, and related functions of the kidneys.
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The kidney plays a very important role in the day-to-day functioning of the body. It filters out toxic waste products from the blood while simultaneously conserving essential substances. This delicate balance between elimination of toxins and retention of essential chemicals is maintained by the nephron. The nephron is the main structural unit of the kidney, and each kidney contains approximately 1 million of them. It is in the nephron where diuretic drugs exert their effect. The initial filtering of the blood takes place in the glomerulus, a cluster of capillaries surrounded by the glomerular capsule. The rate at which this filtering occurs is referred to as the glomerular filtration rate (GFR), and it is used as a gauge of how well the kidneys are functioning as fi lters. Normally about 180 L of blood are fi ltered through the nephrons every day.
The proximal convoluted (twisted) tubule or, more simply, proximal tubule, anatomically follows the glomerulus and resorbs 60% to 70% of the sodium and water from the filtered fluid (ultrafiltrate, resulting from the process of ultrafiltration) back into the bloodstream. Blood vessels surround the nephrons and allow substances to be directly resorbed from or secreted into the bloodstream. This process is one of active transport that requires energy in the form of adenosine triphosphate molecules. The active transport of sodium and potassium ions back into the blood causes the passive resorption of chloride and water. The chloride ions (Cl–) and water passively follows the so-dium ions (Na+) and, to a lesser extent, potassium ions (K+) by osmosis. Another 20% to 25% of sodium is resorbed back into the bloodstream in the ascending loop of Henle. Here it is the chloride that is actively resorbed, and the sodium passively follows it. The remaining 5% to 10% of sodium resorption takes place in the distal convoluted tubule, often called simply the distal tu-bule, which anatomically follows the ascending loop of Henle. In the distal tubule, sodium is actively fi ltered in exchange for po-tassium or hydrogen ions, a process regulated by the hormone aldosterone. The collecting duct is the fi nal common pathway for the fi ltrate that started in the glomerulus. It is here that antidi-uretic hormone acts to increase the absorption of water back into the bloodstream, thereby preventing it from being lost in the urine. . |
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Adregenic Receptor Responses to Stimulation:
Alpha 1 Pupillary muscle |
Receptor:
Alpha 1 Location: Pupilary muscle of iris Response to receptor activation: mydriasis (increased pupil size) |
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Adregenic Receptor Responses to Stimulation:
Alpha 1 Blood vessels |
Receptor:
Alpha 1 Location: blood vessels of skin, viscera Response to receptor activation: constriction |
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Adregenic Receptor Responses to Stimulation:
Alpha 1 GI |
Receptor:
Alpha 1 Location: GI Sphincters Response to receptor activation: constriction |
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Adregenic Receptor Responses to Stimulation:
Alpha 1 Bladder |
Receptor:
Alpha 1 Location: Bladder Sphincter Response to receptor activation: Constriction |
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Adregenic Receptor Responses to Stimulation:
Alpha 2 |
Receptor:
Alpha 2 Location: Presynaptic nerve terminals Response to receptor activation: Inhibit neurotransmitter release |
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Adregenic Receptor Responses to Stimulation:
Beta 1 Heart |
Receptor:
Beta 1 Location: Heart Response to receptor activation: 1) Increased HR 2) Increased force of contraction 3) Increased AV conduction |
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Adregenic Receptor Responses to Stimulation:
Beta 1 Pancreas |
Receptor:
Beta 1 Location: Pancreas Response to receptor activation: Decreased Insulin Release |
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Adregenic Receptor Responses to Stimulation:
Beta 2 Blood Vessels |
Receptor:
Beta 2 Location: Blood vessels of heart, lung, skeletal muscle Response to receptor activation: Dilation |
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Adregenic Receptor Responses to Stimulation:
Beta 2 Liver |
Receptor:
Beta 2 Location: Liver Response to receptor activation: Glycogenolysis |
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Adregenic Receptor Responses to Stimulation:
Beta 2 Kidney |
Receptor:
Beta 2 Location: Kidney Response to receptor activation: Increased renin secretion |
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Adregenic Receptor Responses to Stimulation:
Beta 2 GI Muscle |
Receptor:
Beta 2 Location: GI Muscle Response to receptor activation: decreased motility |
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Adregenic Receptor Responses to Stimulation:
Beta 2 Uterus |
Receptor:
Beta 2 Location: Uterus Response to receptor activation: relaxation |
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Adregenic Receptor Responses to Stimulation:
Beta 2 Bronchial Muscles |
Receptor:
Beta 2 Location: Bronchial Muscles Response to receptor activation: Dilation |
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Adregenic Receptor Responses to Stimulation:
Dopamine |
Receptor:
Beta 2 Location: Liver Response to receptor activation: Dilation of kidney vasculature |
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Cholinergic Receptor Agonists:
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Nicotinic stimulate parasympathethic and sympathetic postganglionic nerve
Muscarinic All parasympathetic target organs eye pupil miosis (constriction), decreased accomidation heart decreased HR, BP decreased Blood vessels vasodialation lungs constriction of bronch, promote secretion Bladder increased bladder pressure, relax sphincter (assists voiding) GI salivation, increased secretions, intestinal tone and motility and aids defication Sweat glands increased secretion |
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What is Epinephrine*?
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also known as ADRENALIN.
an endogenous vasoactive catecholamine. It is drug of choice for asthma attacks and anaphylactic shock. Mimic the effects of the SNS neurotransmitters |
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What is Albuterol*?
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used for respiratory spasms
a selective B2-adrenergic bronchodialator. Bronchodialators- are very effective as antiasthmatic drugs and are used in the treatment of acute attacks because of their rapid onset of action and efficacy. |
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What is Dopamine*?
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shock syndrome, cardiopulmonary arrest
(Intropin)- a naturally occuring catecholamine neurotransmitter in the SNS. It has potent dopaminergic and B1- and A1-adrenergic receptor activity, depending on the dosage. in low doses can dilate blood vessels in the brain, heart, kidneys, and mesentary, whick increases blood flow to these areas. in higher infusion rades can improve cardiac contractility and output. *Dopaminergic receptors: respond only to dopamine |
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What is the Adrenergic action?
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fright, fight, flight
Increases Blood pressure, pulse, and respirations FAST peripheral blood vessels constrict Adrenergic Drugs: epinephrine (adrenalin), isoproterenol (Isuprel), morepinephrine (Levophed), side effects: trachcardia, palpitations, hypertension, nervousness, hyperglycemia. Sympathetic |
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What are the B-adrenergic Blockers?
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SLOW
decrese blood pressure and pulse Beta blockers include: propranolol (Inderal), side effects: hypotension, bradycardia, fatigue, depression, hypoglycemia. Sympathetic |
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What is the Cholinergic action?
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SLOW
Increases secretion (fluids flow) Increases peristalsis and bladder contractions and increases muscle strength Decreases respirations, decrease intraocular pressure, decrease pupils constrict Cholinergic Drugs: bethenechol (Urecholine), neostigmine (Prostigmine), pilocarpine ophth, gtts Side effects: nausea, vomiting, diarrhea, sweating, bradycardia, respirations decrease. Parasympathetic |
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What are cholinergic Blockers?
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(3D effects)
Drying Decrease motilitly GI and GU Dilated Pupils FAST Increase heart rate Anticholinergic drugs: atropine Side effects: dry mouth, urinary retention, constipation, blurred vision, confusion, tachycardia. Parasympathetic |
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What is minipress*?
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Prazosin
an alpha 1 - adrenergic blocking drug primarily used to treat hypertension and to reduce urinary obstruction in men with BHP. In men with BPH, it relieves impaired urinary flow and urinary frequency by relaxing and dilating the vasculature and smooth muscle in the area surrounding the prostates. It also rather dramatically lowers blood pressure. When pt first start taking this drug they need to beware of Orthostatic Hypotension. |
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What is metoprolol*?
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Lopressor, Toprol XL
Beta1-blocker has become a favorite of cardiologist for use in the post-MI patient. |
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Define Cholinergic Drugs.
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Drugs that stimulate the parasympathetic nervous system
The PSNS is the opposing system to the SNS Also known as cholinergic agonists or parasympathomimetics Mimic he effects of the PSNS neurotransmitter: acetylcholine* rest and digest Cholinergic receptors include the nicotinic receptors and muscarinic receptors |
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What is Atropine?
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is a anticholinergics antidote for cholinergics
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What is Bethanechol?
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Urecholine
is a direct acting cholinergic agonist that stimulates the cholinergic receptors located on the smooth muscle of the bladder This stimulation results in increased bladder tone, increased motility, and relaxation of the sphincter of the bladder. It is used in the treatment of acute postoperative and postpartum nonobstructive urinary retention for the management of urinary retention and for the management of urinary retention associated with neurogenti atonoy of the bladder. |
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What is donepezil*?
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Aricept
is an indirect-acting anticholinesterase drug that works centrally in the brain to increase levels of ACh by blocking its breakdown. It is used in the treatment of mild to moderate Alzheimers disease. |
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What is physostigmine*?
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Antilirium
It is an indirect-acting cholinergic drug that works to increase ACh by inhibiting the enzyme that breaks it down. it has been shown to improve muscle strength and is therefore used in the symptomatic treatment of myasthenia gravis. |
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What is digoxin*?
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Positive inotropic drug: cardiac glycosides
Digoxin is the most frequently prescribed cardiac glycoside and the only one currently available in the United States. Prescribed for heart failure and ventricular dysrrhythmias Originally obtained from either the Digitalis purpurea or Digitalis lanata plant, both commonly referred to as foxglove. |
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Adverse affects and Implications for Digoxin
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AA:
(Eyes) Colored Vision, halo, flickering lights (GI) Anorexia, N/V/D For digoxin toxicity: Digibind (digoxin immune Fab therapy) Implications: Assess Hx, drug allergies, contraindications, clinical parameters including blood pressure (Via Apical Pulse for 1 FULL minute), heart and breath sounds IF pulse is <60 or >120 then hold and contact prescriber |
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What is rivastigmine*?
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Exelon
is an indirect-acting cholinergic drug Its mechanism of action is inhibition of the enzyme AChE. It is indicated for the treatment of patients with mild to moderate dementia associated with Alzheimer's disease. |
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What is atropine*?
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Preop control of secretions, therapeutic anticholinergic effect
Naturally occuring antimuscarininc. Used preoperatively to reduce salivation and GI secretions. Effect dosent last to long Indications: used primaryly for cardiovascular disorders Diagnosis of sinus node dysfunction Symptomatic second-degree heart block Sever sinus bradycardia with hemodynamic compromise (advanced life support) Contraindicated in patients with angle-closure glaucoma, adhesions between the iris and lens, certain types of asthma, renal dysfunction etc. |
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What is tolterodine*?
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Detrol
a relatively new muscarinic receptor blocker being widely promoted for treatment of urinary frequency, urgency, and urge incontinence caused by bladder overacting. Should not be used in pt with narrow-angle glaucoma |
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What is digoxin*?
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Lanoxin, Lanoxicaps
Indications: Heart failure, supraventricular dyshythmias is effective for the treatment of both heart failure and atrial fibrillation and flutter. It may also be used clinically to improve myocardial contractility and thus reverse cardiogenic shock or other low cardiac output states. Normal therapeutic drug levels should be between 0.5 and 2 ng/ml. Levels higher than 2ng/ml are typically desirable for the treatment of atrial fibrillation. Digoxin should not be used in pt with Hyperkalemia (serum potassium level over 5mEq/L) |
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What is digoxin immune Fab (Digibind)*?
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given for toxicity of digoxin
Indicated for use in: Hyperkalemia in a patient with digitoxicity Life-threatening cardiac dysrhythemias Life-threatening digoxin overdose You are predisposed for digoxin toxicity if you have Hkypolalemia |
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What is lidocaine*?
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antidisrhytmic
used for ventricular dysrhythmias only stops iritability of ventricles |
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What is adenosin (Adenocard)*?
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Half live is only 10 sec
Slows conduction through the AV node Used to convert paroxysmal supraventricular tachycardia to sinus rhythm Only administered as fast IV push May cause asystole for a few seconds |
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Inotropic drugs
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drugs affect the force of myocardial contraction; positive inotropics (e.g., digoxin) increase the force of contractions and negative inotropics (e.g., beta-blockers, calcium channel blockers) decrease myocardial contractility.
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Chronotropic drugs
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drugs affect the rate at which the heart beats (beats/min); positive chronotropic drugs (e.g., epinephrine, atropine) increase the heart rate and negative chronotropic drugs decrease the heart rate.
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Dromotropic drugs
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drugs affect the conduction of electrical impulses through the heart; positive dromotropic drugs increase the speed of electrical impulses through the heart, whereas negative drugs have the opposite effect.
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What are diuretics?
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a drug or any other subtance that tends to promote the formation and excretion of urine.
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What are loop diuretics?
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drugs bumetanide, ethacrynic acid, furosemide (Lasix), torsemide
Are considered the most effective diuretic; very potent that act along the thick ascending limb of the loop of Henle blocking chloride and secondarily, sodium reabsorption They are particularly useful when rapid diuresis is needed, b/c of their rapid onset of action. Even when kidney function diminishes, they often can still work. Has the following CV effects: reduced bp reduced pulm vas resistance reduced systemic vas resistance reduced CVP reduced left vent end diastolic press Common adverse affects: dizziness, H/A, tinnitus, blurred vision, N/V/D, agranulocytosis, thrombocytopenia, neutropenia, hypokalemia, hyperglycemia, hyperuricemia |
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Vaughn Williams Classification of Antidysrhythmics
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Class 1a: quinidine, procainamide, disopyramide
*quinidine is given in Rx of atrial dysfunction Class 1b: mexiletine, phenytoin, lidocaine *lidocaine can be given for ventricular dysrhythmia (via IV) |
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Define Ischemia
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Poor blood supply to an organ; when the organ involved is the heart, the condition is called ischemic heart disease.
Ischemic heart disease is the number one killer in the United States today, and the primary cause is a disease of the coronary arteries known as atherosclerosis (fatty plaque deposits in the arterial walls). |
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What is Nitroglycerin?
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Prototypical nitrate given for ischemia heart conditions such as angina. It is most often given sublingually or bucally due to the large first pass effect but can also be given orally, IV, transdermal patch, transdermal spray or as an ointment.
The most common adverse affects are H/A (huge!); diminished intensity and frequency of H/A with continued use Tachycardia, postural hypotension, decreased BP Tolerance which can be prevented or minimized by allowing a regular nitrate free pd to allow enzyme pathways to replenish |
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What are drugs used to treat angina pectoris?
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Nitrates, nitrites, beta blockers, and Calcium channel blockers
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Describe the therapeutic affect of Nitrates / nitrites
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Therapeutic Action:
Cause vasodilation due to relaxation of smooth muscle potent dilating effect on coronoary arteries vasodilation results in reduced myocardial oxygen demand cause dilation of small and large coronary arteries which results in more oxygen to ischemic myocardial tissue |
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Describe mechanism of action for Beta Blockers in relation to the heart in treatment for angina.
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Beta 1 receptors are blocked. decreases HR resulting in decreased myocardial oxygen demand and increased oxygen delivery to the heart.
NOTE: Side affects include constipation, H/A, lightheadedness, hypotension, dizziness, After an MI, a high level of circulating catecholamines are irritating the heart causing an imbalance in supply and demand ration and even leading to life threatening dysrhythmias. Beta blockers block harmful effect of catecholamines improving survival after MI |
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What is Lopressor? (metoprolol)
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a cardioselective Beta 1 adrenergic receptor blocker used for prophylactive treatment of angina and is often shown efficiency in treating pts after an MI
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Special considerations for Nitroglycerin
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Medications should be stored in airtight dark glass bottle with a metal cap and no cotton filler to preserve potency.
Advise pts to keep a fresh supply as after 3 months the drug loses potency. If pt takes sublinqually and does NOT feel burning sensation potency has been lost If after 3 tablets/15 min of treatment no relief is found call 911 immediately |
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What group of drigs is considered the "drug of choice" for hypertension and HF?
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ACE Inhibitors or ACEI's
Can be combined with thiazide diuretic or CCB |
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What is sodium nitroprusside (Nitropress)?
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Drug normally used in the intensive care setting for severe hypertensive emergencies and is titrated to effect by IV infusion.
B/c of high risk for cyanide toxicity at max doses (up to 10mcg/kg/min) use is limited to 10 min. |
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What are osmotic diuretics?
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Diuretics used special situations such as acute renal failure. Known for getting kidneys going again. Drug most commonly used is mannitol (Osmitrol). Also used in cerebral edema and for use in decreasing ICP
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What are potassium sparing diuretics?
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A typical side effect of diuretic use is loss of potassium. PSD's such as spironolactone (Aldactone) is a synthetic steroid. It is often prescribed for children who suffer from heart failure. It is considered the least effective but is also potassium sparing.
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What are anticoagulants?
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drugs that inhibit the formation of clotting factors and therefore prevent clots. Are considered prophylactive as they have no affect on clots that are already formed.
Adverse affect: bleeding is the most common Common drugs are enoxaparin (Lovenox), warfarin (Coumadin) Antidote for OD, Toxicity is protamine sulfate. |
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What are antiplatelets?
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drugs that prevent platelet plugs from forming by inhibiting platelet aggregation, which can be beneficial in preventing heart attacks and strokes. Most common antiplatelet is Aspirin
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What are thrombolytics?
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A very expensive coagulation modifier produced or found in beta-hemolytic streptococci (streptokinase (SK))
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