Chapter 36 Nursing Management: Dysrhythmia Flashcards
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asystole, p. 795
represents the total absence of ventricular electrical activity
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atrial fibrillation, p. 796
a cardiac dysrhythmia characterized by a total disorganization of atrial electrical activity without effective atrial contraction.
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atrial flutter, p. 795
an atrial tachydysrhythmia identified by recurring, regular, sawtooth-shaped flutter waves.
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automatic external defibrillator (AED), p. 802
XX
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cardiac pacemaker, p. 803
an electronic device used to increase the heart rate in severe bradycardia by electrically stimulating the heart muscle.
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complete heart block, p. 798
third-degree atrioventricular heart block in which no impulses from the atria are conducted to the ventricles.
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dysrhythmias, p. 787
XX
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premature atrial contraction (PAC), p. 794
contraction originating from an ectopic focus in the atrium in a location other than the sinus node.
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premature ventricular contraction (PVC), p. 799
a contraction originating in an ectopic focus in the ventricles.
Key Terms:
telemetry monitoring, p. 790
XX
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ventricular fibrillation (VF), p. 800
a severe derangement of the heart rhythm characterized on electrocardiogram (ECG) by irregular undulations of varying contour and amplitude.
Key Terms:
ventricular tachycardia (VT), p. 799
a condition that occurs when an ectopic focus or foci fire repetitively and the ventricle takes control as the pacemaker.
Automaticity
Ability to initiate an impulse spontaneously and continuously
Excitability
Ability to be electrically stimulated
Conductivity
Ability to transmit an impulse along a membrane in an orderly manner
Contractility
Ability to respond mechanically to an impulse
P Wave
0.06-0.12 seconds
Represents time for the passage of the electrical impulse through the atrium causing atrial depolarization (contraction). Should be upright.
PR Interval
0.12-0.20 seconds
Measured from beginning of P wave to beginning of QRS complex. Represents time taken for impulse to spread through the atria, AV node and bundle of His, bundle branches, and Purkinje fibers, to a point immediately preceding ventricular contraction.
QRS Complex
Q wave
<0.03 seconds
First negative (downward) deflection after the P wave, short and narrow, not present in several leads.
QRS Complex
R wave
First positive (upward) deflection in the QRS complex.
QRS Complex
S wave
First negative (downward) deflection after the R wave.
QRS Interval
<0.12 seconds
Measured from beginning to end of QRS complex. Represents time taken for depolarization (contraction) of both ventricles (systole).
ST Segment
0.12 seconds
Measured from the S wave of the QRS complex to the beginning of the T wave. Represents the time between ventricular depolarization and repolarization (diastole). Should be isoelectric (flat).
T Wave
0.16 seconds
Represents time for ventricular repolarization. Should be upright.
QT Interval
0.34-0.43 seconds
Measured from beginning of QRS complex to end of T wave. Represents time taken for entire electrical depolarization and repolarization of the ventricles.
Sinus bradycardia
The conduction pathway is the same as that in sinus rhythm but the SA node fires at a rate less than 60 beats/minute
Symptomatic bradycardia
Refers to an HR that is less than 60 beats/minute and is inadequate for the patient’s condition, causing the patient to experience symptoms (e.g., chest pain, syncope).
