NUR 202 Module 5 Quiz B
To determine whether a client is experiencing acute coronary syndrome (ACS), which component of the electrocardiogram would the nurse analyze? 1. P wave 2. PR interval 3. QRS complex 4. ST segment
4 Elevation or depression of the ST segment is indicative of ACS because of changes in cardiac electrical activity that occur with ischemia and injury. P wave changes are not used to diagnose ACS. Changes in the QRS complex do not occur with ACS. Changes in the PR interval are not diagnostic of ACS.
After the nurse has presented a staff education session on the use of adenosine for supraventricular tachycardia, which statement by a staff member indicates that the teaching has been effective? 1. "We will need a crash cart available at the client's bedside." 2. "We will plan to schedule the anesthesiologist to be available." 3. "The medication should be injected over at least 1 to 2 minutes." 4. "Infusion of normal saline will be needed before medication injection."
1 Adenosine can cause significant bradycardia and short episodes of asystole along with hypotension, so emergency equipment from the crash cart should be at the bedside. Sedation or anesthesia is not needed with adenosine administration. Adenosine is injected over 1 to 3 seconds; slow administration prevents the medication from being effective. A bolus of normal saline is used after adenosine administration to rapidly infuse the medication, but saline is not needed before administration.
When a client's cardiac monitor shows ventricular tachycardia, which action would the nurse take first? 1. Check for a pulse. 2. Start cardiac compressions. 3. Prepare to defibrillate the client. 4. Administer oxygen via an Ambu bag.
1 The treatment of ventricular tachycardia depends on whether the client has a pulse and is symptomatic with the dysrhythmia. Cardiac compressions would not be initiated if there was a pulse. Administering oxygen via an Ambu bag would occur only if the client was not breathing. The client with pulseless ventricular tachycardia may be defibrillated, but the nurse first needs to check for a pulse.
When caring for a client with acute coronary syndrome who has frequent premature ventricular complexes (PVCs), the nurse will be most concerned about PVCs occurring in which phase of the cardiac cycle? 1. P wave 2. T wave 3. P-R interval 4. QRS complex
2 The T wave is the period of repolarization of the ventricles; stimulation of the ventricles during this vulnerable period often causes ventricular fibrillation. If a premature ventricular contraction strikes on the P wave, it will not cause ventricular fibrillation; the P wave represents atrial contraction. The P-R interval represents the time it takes the impulse to travel from the sinoatrial (SA) node to the ventricular musculature, and a PVC during the PR interval will not cause ventricular fibrillation. QRS complex is the term used to represent the entire phase of ventricular contraction.
When a client has supraventricular tachycardia that has persisted despite treatment with vagal maneuvers and medications, which collaborative intervention will the nurse anticipate to treat the dysrhythmia? 1. Defibrillation 2. Pacemaker placement 3. Synchronized cardioversion 4. Cardiac resynchronization therapy
3 Synchronized cardioversion is application of a shock that is timed to land on the R wave to depolarize the myocardium and allow the normal cardiac pacemaker in the sinoatrial node to take over normal cardiac stimulation. Defibrillation is not synchronized and might cause fatal dysrhythmias such as ventricular fibrillation if used on a client with supraventricular tachycardia. A pacemaker would be used for slow heart rates such as might occur with atrioventricular blocks. Cardiac resynchronization therapy is used for clients with severe left ventricular failure to synchronize the contraction of the right and left ventricles and improve cardiac output.
