Telemetry
The nurse is analyzing the client's rhythm when the nurse notes multiple premature ventricular contractions (PVCs). Each PVC occurs in no particular pattern and looks like all other PVCs. How will the nurse interpret this finding?
A single ectopic focus produces PVC waveforms that look alike, called unifocal PVCs. Waveforms of PVCs arising from multiple foci are not identical in shape and are called multifocal PVCs. PVCs may occur in a predictable pattern, such as every other beat (bigeminal) and every third beat (trigeminal). Two consecutive PVCs are called a couplet.
Regarding systole of the cardiac cycle, which of the following occurs immediately after electrical conduction reaches the AV node?
AV node conducts signal to Bundle of His, which runs down the path in between the 2 ventricles to the Perkinje Fibers
Which dysrhythmia would the nurse identify on this client's electrocardiogram (ECG) strip?
Beats 2 and 4 are premature ventricular complexes or beats. The impulse originates in the ventricles, and it occurs before the next expected ventricular beat. Asystole is characterized by an absence of electrical and mechanical cardiac activity, with no countable heartbeat. Atrial flutter is characterized by an atrial rate of 250 to 350 regular beats per minute, more than 100 irregular ventricular beats per minute, a sawtooth P wave, variable PR intervals, and normal QRS complexes. Ventricular fibrillation is characterized by lack of organization in electrical impulses, conduction of impulses, and ventricular contractions.
Regarding systole of the cardiac cycle, which action most likely occurs immediately after the conduction signal reaches the bundle of His?
Bundle of His signals Purkinje Fibers to contract ventricles, distributing electrical signals throughout the ventricles
The nurse notes that the client's cardiac rhythm strips show more P waves than QRS complexes. There is no relationship between the atria and the ventricles. How should the nurse interpret this rhythm strip? First degree atrioventricular (AV) block Second degree AV block Mobitz I (Wenckebach) Second degree AV block Mobitz II Third degree AV block (complete heart block)
D. Third degree AV block (complete heart block)
When a client's rhythm strip shows that the P and QRS waves are consistent, with a P wave preceding every QRS complex and a PR interval of 0.26 seconds, how would the nurse interpret the rhythm?
In first degree AV block, P and QRS waves are consistent in shape. A P wave precedes every QRS complex, and the PR interval is greater than 0.20 seconds. Normal sinus rhythm reflects normal conduction of the sinus impulse through the atria and ventricles; PR interval is 0.12 to 0.20 seconds, and every QRS is preceded by a P wave. In second degree AV block, 1 or more P waves are not conducted to the ventricles and therefore not followed by a QRS. In third degree AV block or complete heart bock, the QRS has no relationship with P waves.
Regarding systole of the cardiac cycle, what prevents backflow of blood into the left atrium?
Mitral Valve closes to prevent backflow during ventricular contraction.
Which of the following allows blood to travel from the left atrium to the left ventricle?
Mitral Valve opens
When the nurse is analyzing an electrocardiogram (ECG), which waveform illustrates atrial depolarization?
Option a reflects the P wave; it represents the electrical impulse starting at the sinus node and spreading throughout the atria (atrial depolarization). Waveform b reflects the QRS complex; it represents depolarization of the ventricles. Option c reflects the T wave; it represents repolarization of the ventricles. Waveform d reflects the U wave; it is believed to reflect late ventricular repolarization or repolarization of the Purkinje fibers; it is sometimes identified in clients with hypokalemia.
Where will the nurse place the V1 lead when obtaining a 12-lead electrocardiogram?
Positions for these 6 leads are as follows: V1: fourth intercostal space, right sternal border; V2: fourth intercostal space, left sternal border; V3: halfway between V2 and V4; V4: fifth intercostal space, left midclavicular line; V5: fifth intercostal space, left anterior axillary line; V6: fifth intercostal space, left midaxillary line.
Which event prevents backflow of blood into the right ventricle?
Pulmonary valve is closed during diastole. This allows blood to fill the ventricles properly, and also prevents backflow into ventricle from previous systolic cycle.
Regarding systole of the cardiac cycle, which most likely allows blood to enter the lungs?
Pulmonary valve opens to the lungs allowing blood to flow from right ventricle to lungs
What event initiates myocardial contraction?
SA Node fires At the end of DIASTOLE, the SA node initiates contraction of the atria
The nurse is assessing an electrocardiogram (ECG) rhythm strip. Which component of the tracing will the nurse observe to determine ventricular depolarization?
The QRS complex represents ventricular depolarization. The P wave represents atrial depolarization. Normally a P wave indicates that the sinoatrial node initiated the impulse that depolarized the atrium. The T wave represents ventricular repolarization. The interval from the beginning of the P wave to the next deflection from the baseline is called the PR interval and represents depolarization of the sinoatrial node, both atria, and the atrioventricular node.
When calculating a client's heart rate on an electrocardiogram (ECG) strip, which action would the nurse take?
The heart rate is calculated by counting QRS complexes, which represent ventricular depolarization. The P wave represents atrial depolarization and would be used if the atrial rate was being calculated. The T wave represents ventricular repolarization and is not used to calculate heart rate. The PR interval represents depolarization of the atria and atrioventricular node and is not used in heart rate calculation.
When admitting a client with syncope and this electrocardiogram (ECG) rhythm, which medication will the nurse anticipate administering for sinus bradycardia?
This rhythm strip reflects sinus bradycardia. Sinus bradycardia has PQRST complexes within acceptable limits, but the rate is less than 60 beats/minute. In this strip the PR interval is 0.16, the rhythm is regular, and the rate is 40 beats/minute. Atropine, an anticholinergic that increases the heart rate, is administered when the heart rate is so slow that it causes symptoms such as syncope. Digoxin is a cardiac glycoside that slows the heart rate. Enalapril is an angiotensin-converting enzyme (ACE) inhibitor that lowers blood pressure. Metoprolol is a beta blocker that slows the heart rate.
Regarding systole of the cardiac cycle, which action most likely prevents backflow of blood into the right atrium?
Tricuspid Valve closes
Which of the following allows blood to travel from the right atrium to the right ventricle?
Tricuspid Valve opens
What occurs during diastole after the tricuspid and mitral valve open?
Ventricles fill with blood due to atrial contraction
Which dysrhythmia is this client on the telemetry unit exhibiting?
Ventricular tachycardia has a rate of 140 beats/minute to 200 beats/minute or even 250 beats/minute; the rhythm is usually regular but may vary. P waves are unidentifiable. PR intervals are unmeasurable. QRS complexes are wide and bizarre. Atrial flutter is characterized by sawtooth flutter waves at a rate of 200 beats/minute to 350 beats/minute and a ventricular rate of usually 75 beats/minute to 150 beats/minute; flutter wave to QRS complex ratio is usually 2:1, 3:1, or 4:1. Atrial fibrillation is characterized by an atrial rate of 350 beats/minute to 600 beats/minute and a variable ventricular rate; the rhythm is grossly irregular. Ventricular fibrillation reflects a rapid, feeble twitching/quivering of the ventricles; it has an irregular sawtooth configuration with no identifiable PR intervals or QRS complexes.
Which of the following events prevents backflow of blood into the left ventricle?
aortic valve closes
Regarding systole of the cardiac cycle, which most likely allows blood to enter systemic circulation?
aortic valve opens allowing O2 blood to flow from left ventricle to systemic circulation
Regarding systole of the cardiac cycle, which structure sits at the junction of the atria and ventricles?
the SA node signals starts in diastole and reaches the AV node at the start of systole. AV node sits at the junction of the atria and ventricles
What are the atrioventricular valves?
tricuspid and mitral (bicuspid) valves
Which event isovolumetrically decreases ventricular pressure?
ventricles relax