Cardiovascular and Renal Flashcards
(40 cards)
A patient has been prescribed lidocaine (Xylocaine). What does the nurse understand as the reason for this medication order?
Ventricular arrhythmias:
Lidocaine is a sodium channel–blocking drug used specifically to treat ventricular arrhythmias.
The nurse is reviewing emergency protocols and administration of adenosine (Adenocard). What is a vitally important task to remember when administering adenosine?
Give it as a rapid intravenous push.
Adenosine must be given as rapidly as possible, followed by a 50-mL normal saline flush in order to get all of the medication into the circulation quickly since the half-life of adenosine is less than 10 seconds.
To prevent the occurrence of cinchonism in a patient prescribed quinidine, what does the nurse emphasize as important?
Avoid drinking grapefruit juice.
Grapefruit juice can also inhibit the metabolism of quinidine, which increases the risk of cinchonism.
Adenosine is used to treat which condition?
Paroxysmal supraventricular tachycardia (PSVT):
The only therapeutic indication of use for adenosine is the treatment of PSVT.
Sodium channel blockers are considered which class of antidyshythmic drugs?
Class I
The patient has been prescribed ibutilide (Corvert), a class III antiarrhythmic drug. The nurse is aware that this drug has been prescribed for which reason?
Conversion of recent-onset atrial fibrillation and flutter:
Ibutilide is specifically indicated only for treatment of recent-onset atrial fibrillation and flutter.
Before administering a dose of an antidysrhythmic drug to an assigned patient, which assessments would be of highest priority?
Apical pulse and blood pressure:
Antiarrhythmic drugs can cause both hypotension and bradycardia; therefore it is important to assess blood pressure and apical pulse before administration. Peripheral pulses are not as reliable as the apical pulse assessment.
Which class of drugs is used to treat both hypertension and dysrhythmias?
Calcium channel blockers:
Calcium channel blockers are effective in treating both hypertension and dysrhythmias secondary to their negative inotropic and chronotropic effects.
Calcium channel blockers have which pharmacodynamic effect?
Coronary vasodilation: Calcium channel blockers cause coronary vasodilation, a negative inotropic effect, a negative chronotropic effect, and a negative dromotropic effect.
The most severe adverse effects of amiodarone are evidenced in which body system?
Pulmonary:
Patients taking amiodarone must have baseline and serial pulmonary function tests in order to monitor for potential pulmonary toxicity.
For which potential adverse effects would the nurse monitor patients prescribed amiodarone? (Select all that apply.)
Bluish skin discoloration
Hypothyroidism
Photosensitivity
any deviation from the normal rhythm of the heart
dysrhythmia
“no rhythm” implies asystole or no heartbeat at al
arrhythmia
when antidysrhythmic drugs cause dysrhythmias
prodysrhythmic
SA node
the natural pacemaker of the heart because it spontaneously depolarizes the most frequently; have a slower upstroke velocity
resting membrane potential (RMP)
an important determinant of the rate of its impulse conduction to other cells
Common Dysrhythmias
Supraventricular dysrhythmias;
Ventricular dysrhythmias;
Dysrhythmias
Supraventricular dysrhythmias
originate above the ventricles in the SA or AV node or atrial myocardium.
Ventricular dysrhythmias
originate below the AV node in the His-Purkinje system or ventricular myocardium
Dysrhythmias
originate outside the conduction system (i.e., in atrial or ventricular cells) are called ectopic and their points of origin are called ectopic foci
Conduction blocks
dysrhythmias that involve disruption of impulse conduction between the atria and ventricles through the AV node, directly affecting ventricular function
may originate in the His-Purkinje system
Class I
Membrane-stabilizing drugs (e.g., class Ia, quinidine; class Ib, lidocaine; class Ic, flecainide); these drugs exert their actions on the sodium (fast) channels
Class II
Beta-adrenergic blockers that depress phase 4 depolarization (e.g., atenolol);
commonly used as antihypertensives, working by blocking sympathetic nervous system stimulation to the heart and, as a result, the transmission of impulses in the heart’s conduction system. These drugs mostly affect slower-conducting cardiac tissues
Class III
Drugs that prolong repolarization in phase 3 (e.g., amiodarone and dofetilide); these drugs affect fast tissue and are most commonly used to manage dysrhythmias that are difficult to treat
