Critical Care Nursing Cardiovascular Chapter 8
What is the normal rate for the SA node when the patient is at rest?
60 to 100 beats per minute
The nurse is calculating the rate for a regular rhythm. There are 20 small boxes between each P wave and 20 small boxes between each R wave. What is the ventricular rate?
75 beats/min
The patient's heart rate is 70 beats per minute with the P waves coming after the QRS complex. The nurse correctly determines that the patient is demonstrating what heart rhythm?
An accelerated junctional rhythm
The nurse working on the night shift when notices sinus bradycardia on the patient's cardiac monitor. What initial action should the nurse take?
Assess for hemodynamic instability.
The nurse is talking with the patient when the monitor alarms and shows a wavy baseline without a PQRST complex. The nurse should take what action immediately?
Assess the patient and the electrical leads.
The patient is admitted with sinus pauses causing periods of loss of consciousness. The patient is currently asymptomatic, awake and alert, but fatigued and answers questions appropriately. When admitting this patient, what should be the nurse's initial action?
Assess the patient's medication profile.
The nurse is reading the cardiac monitor and notes that the patient's heart rhythm is extremely irregular and there are no discernible P waves. The ventricular rate is 90 beats per minute, and the patient is hemodynamically stable. The nurse realizes that the patient is demonstrating what rhythm?
Atrial fibrillation
The patient is in chronic junctional escape rhythm with no atrial activity noted. Studies have demonstrated normal AV node function. This patient may be a candidate for which type of pacing?
Atrial pacing
The nurse notices ventricular tachycardia on the heart monitor. When the patient is assessed, the patient is found to be unresponsive with no pulse. The nurse should take what action immediately?
Begin cardiopulmonary resuscitation and advanced life support.
Sinus bradycardia is a symptom of which of the following? (Select all that apply.)
Calcium channel blocker medication Beta-blocker medication Athletic conditioning Hypothermia
The patient is admitted with a condition that requires cardiac rhythm monitoring. To apply the monitoring electrodes, the nurse must first take what action?
Clip chest hair if needed.
The patient's heart rate is 165 beats per minute and the cardiac monitor shows a rapid rate with narrow QRS complexes. The P waves cannot be seen, but the rhythm is regular. The patient's blood pressure has dropped from 124/62 to 78/30; skin is cold and diaphoretic and the patient is reporting nausea. The nurse prepares the patient for what intervention?
Emergent cardioversion
The rhythm on the cardiac monitor is showing numerous pacemaker spikes, but no P waves or QRS complexes following the spikes. The nurse realizes this as what?
Failure to capture
The patient has a permanent pacemaker in place with a demand rate set at 60 beats/min. The cardiac monitor is showing a heart rate of 44 beats/min with no pacemaker spikes. How does the nurse interpret this?
Failure to pace
Which of the following are common causes of sinus tachycardia? (Select all that apply.)
Hyperthyroidism Hypovolemia Heart Failure
The patient has an irregular heart rhythm. To determine an accurate heart rate, the nurse will take what action first?
Identify the markers on the ECG paper that indicate a 6-second strip.
The QT interval is the total time taken for ventricular depolarization and repolarization. Prolongation of the QT interval will result in what outcome?
Increase in the risk of lethal dysrhythmias.
Why is the sinus node identified as the pacemaker of the heart?
It contains the fastest pacemaker cell in the heart.
The patient's heart rhythm shows an inverted P wave with a PR interval of 0.06 seconds. The heart rate is 54 beats per minute. The nurse recognizes the rhythm as a junctional escape rhythm, and understands that the rhythm is due to what cause?
Loss of sinus node activity
The nurse notices that a patient is in first-degree AV block but everything else about the rhythm is normal. The nurse should be prepared to take what action?
Monitor the rhythm and patient's condition.
The nurse is examining the patient's cardiac rhythm strip in lead II and notices that all of the P waves are upright and look the same except one that has a different shape and is inverted. The nurse realizes that the P wave with the abnormal shape is probably a result of what?
Originating from some area in the atria other than the SA node.
What is one of the functions of the atrioventricular (AV) node?
Slowing the impulse arriving from the SA node
The nurse is caring for a patient diagnosed with atrial fibrillation. Sequelae that place the patient at greater risk for mortality/morbidity include which of the following? (Select all that apply.)
Stroke Pulmonary emboli Decreased cardiac output
Which statement is true about a patient diagnosed with sinus arrhythmia?
The heart rate varies, dependent on vagal tone and respiratory pattern.
The patient has a permanent pacemaker inserted. The provider has set the pacemaker to the demand mode at a rate of 60 beats per minute. How does the nurse interpret this?
The pacemaker will pace only if the patient's intrinsic heart rate is less than 60
The normal width of the QRS complex is which of the following? (Select all that apply.)
0.06 to 0.10 seconds. 1.5 to 2.5 small boxes.
Because of the location of the AV node, the possible P waveforms that are associated with junctional rhythms include which of the following? (Select all that apply.)
No P wave Inverted P wave Shortened PR interval P wave after the QRS complex
When assessing the 12-lead electrocardiogram (ECG) or a rhythm strip, it is helpful to understand that the electrical activity is viewed in relation to the positive electrode of that particular lead. What is the effect on the inflection when an electrical signal is aimed directly at the positive electrode?
Upright
The patient scheduled to have a permanent pacemaker implanted asks the nurse, "How long will the battery in this thing last?" What answer should the nurse provide?
"Battery life varies depending on usage, but it can last up to 10 years."
The nurse understands what to be true of a third-degree AV block?
None of the P waves are conducted to the ventricles
The patient is having premature ventricular contractions (PVCs). What is the nurse's greatest concern?
The proximity of the R wave of the PVC to the T wave of a normal beat.
The patient is in third-degree heart block (complete heart block) and is symptomatic. The treatment for this patient is which of the following? (Select all that apply.)
Transcutaneous pacemaker Temporary transvenous pacemaker Permanent pacemaker
Electrocardiogram (ECG) paper contains a standardized grid where the horizontal axis measures time and the vertical axis measures voltage or amplitude. The nurse must understand that each horizontal box indicates what?
40 milliseconds or 0.04 seconds duration
The patient is admitted with a fever and rapid heart rate and a temperature of 103° F (39.4°C).The nurse places the patient on a cardiac monitor and finds the patient's atrial and ventricular rates are above 105 beats per minute. P waves are clearly seen and appear normal in configuration. QRS complexes are normal in appearance and 0.08 seconds wide. The rhythm is regular, and blood pressure is normal. What should be the nurse's initial focus?
Treatment to lower temperature
