Dysrhythmias: Interpretation and Nursing Actions Practice Questions
20 free Dysrhythmias: Interpretation and Nursing Actions practice questions for the NCLEX Exam. Tap an option to answer — you get instant feedback, the correct answer, and a detailed explanation for every question.
Which dysrhythmia is characterised by absent discrete P waves, an irregularly irregular ventricular rhythm, and often a rapid rate?
- A Sinus tachycardia
- B Atrial fibrillation
- C Atrial flutter
- D Ventricular tachycardia
Correct answer: Atrial fibrillation
Atrial fibrillation is characterised by absent discrete P waves, an irregularly irregular ventricular rhythm, and often a rapid rate.
What rhythm is described by a prolonged PR interval (>0.20 sec) with every P wave followed by a QRS complex?
- A First‐degree AV block
- B Second‐degree AV block type I (Wenckebach)
- C Third‐degree AV block
- D Ventricular escape rhythm
Correct answer: First‐degree AV block
First‐degree AV block is identified by a consistently prolonged PR interval with each atrial impulse conducted; it often requires monitoring rather than immediate intervention.
What is the immediate action for a patient presenting with rapid, wide QRS complex at 200/min without a palpable pulse?
- A Give a rapid adenosine IV push
- B Prepare for synchronized cardioversion
- C Begin unsynchronized defibrillation with CPR
- D Obtain a 12-lead ECG before any intervention
Correct answer: Begin unsynchronized defibrillation with CPR
A pulseless wide QRS tachycardia at ~200 suggests ventricular tachycardia without pulse; unsynchronized defibrillation and CPR are indicated emergently.
What nursing intervention takes highest priority in a stable patient newly diagnosed with atrial fibrillation and rapid ventricular response?
- A Perform immediate synchronized cardioversion
- B Assess perfusion status and initiate rate control per protocol
- C Discharge the patient home without any follow-up
- D Administer digoxin without additional monitoring
Correct answer: Assess perfusion status and initiate rate control per protocol
In stable A‐fib with rapid ventricular response, priority is assessing perfusion and initiating rate control rather than emergent cardioversion.
Which medication is the nurse likely to prepare for a symptomatic patient in sinus bradycardia (rate 40/min) with dizziness and hypotension?
- A Adenosine
- B Atropine
- C Amiodarone
- D Digoxin
Correct answer: Atropine
Atropine is the first‐line medication for symptomatic bradycardia to increase heart rate by blocking vagal tone.
Which rhythm is most consistent with a sawtooth pattern in the atria and a ventricular rate of 150/min?
- A Atrial fibrillation
- B Atrial flutter
- C Complete heart block
- D Junctional rhythm
Correct answer: Atrial flutter
Atrial flutter shows atrial rates ~250–350/min, often with sawtooth F waves on ECG, and the ventricular rate may be a multiple of the atrial.
What signs in a patient on digoxin indicate digitalis toxicity?
- A Isolated hypokalemia with no other findings
- B Nausea, visual disturbances, and new dysrhythmias
- C Signs of acute myocardial ischemia
- D Expected, benign therapeutic side effects
Correct answer: Nausea, visual disturbances, and new dysrhythmias
Classic signs of digitalis (digoxin) toxicity include GI upset (anorexia, nausea, vomiting), visual disturbances (yellow-green halos), and dysrhythmias such as PVCs or AV block. Hypokalemia predisposes to toxicity but is not itself a sign.
What is the hallmark ECG finding in a patient with third‐degree (complete) AV block?
- A PR interval progressively lengthening until a QRS is dropped
- B No relationship between P waves and QRS complexes
- C PR interval constant but >0.20 sec
- D Ventricular rate faster than atrial rate
Correct answer: No relationship between P waves and QRS complexes
In a third-degree AV block, there is complete dissociation between atrial and ventricular activity; P waves and QRS complexes occur independently.
Which statement regarding pacemaker post-implantation is correct for a patient being instructed by the nurse?
- A “Avoid all physical activity for a full six weeks.”
- B “Temporary hiccups can occur if the lead stimulates the diaphragm.”
- C “No further follow-up or device monitoring will be needed.”
- D “You may stop your anticoagulant medication right away.”
Correct answer: “Temporary hiccups can occur if the lead stimulates the diaphragm.”
Diaphragmatic stimulation (hiccups) may occur early after pacemaker lead placement; activity restrictions are less than 6 weeks and follow-up for device function is essential.
What is the priority nursing action immediately post-procedure when a patient’s rhythm converts from atrial fibrillation to normal sinus rhythm following cardioversion?
- A Remove the ECG leads and discontinue monitoring
- B Continue ECG monitoring and anticoagulation; watch for recurrence or emboli
- C Reassure the patient that no further care is required
- D Observe only the catheter insertion site for bleeding
Correct answer: Continue ECG monitoring and anticoagulation; watch for recurrence or emboli
After cardioversion of A‐fib, there is a risk of recurrent dysrhythmia, thromboembolism, and monitoring remains crucial; anticoagulation and rhythm monitoring continue.
What does a QRS complex duration longer than 0.12 seconds indicate when evaluating ECG strips?
- A Normal ventricular conduction velocity
- B Bundle branch block or ventricular rhythm origin
- C Pure atrial origin of the rhythm
- D Sinus arrhythmia with normal conduction
Correct answer: Bundle branch block or ventricular rhythm origin
A QRS wider than 0.12 sec suggests delayed ventricular conduction, e.g., bundle branch block, or a ventricular origin of the rhythm.
What is the best nursing action for a patient showing premature ventricular complexes (PVCs) but is asymptomatic with no pulse deficit?
- A Prepare for immediate defibrillation
- B Document and monitor for worsening frequency
- C Administer IV adenosine immediately
- D Discontinue cardiac monitoring entirely
Correct answer: Document and monitor for worsening frequency
Isolated PVCs in an asymptomatic patient may be benign; the nurse should monitor for increased frequency, coupling, multifocal or runs of VT, and assess the patient’s status.
What action should the nurse take for a patient with atrial fibrillation and rapid ventricular response along with hypotension if the patient is recognised as unstable?
- A Perform vagal maneuvers only
- B Synchronized cardioversion
- C Oral beta-blocker within 24 hours
- D Continued observation only
Correct answer: Synchronized cardioversion
Unstable A‐fib generally calls for synchronized cardioversion rather than delayed pharmacotherapy.
What is the immediate action for a telemetry patient whose rhythm suddenly flattens out and becomes asystole?
- A Check the lead wires for displacement
- B Start CPR and call a code blue team
- C Administer adenosine
- D Give the patient oxygen and wait
Correct answer: Start CPR and call a code blue team
Asystole (flatline) is a non‐shockable rhythm and requires immediate CPR and advanced life support rather than waiting or giving adenosine.
Which risk factor most predisposes to dysrhythmias according to the nurse?
- A Hypokalemia
- B Age under 20 years only
- C Vegetarian diet only
- D Chronic liver disease only
Correct answer: Hypokalemia
Electrolyte imbalances are major precipitating factors for dysrhythmias because they alter cardiac electrical conduction.
What do early P waves with narrow QRS complexes and pauses after the beat indicate on an ECG?
- A Atrial flutter with sawtooth waves
- B Premature atrial contractions (PACs)
- C Ventricular tachycardia with wide QRS
- D Junctional escape rhythm with absent P
Correct answer: Premature atrial contractions (PACs)
PACs appear as early P waves usually with a narrow QRS and a compensatory pause; often benign but should be monitored for frequency and patient symptoms.
For a patient on continuous IV amiodarone for ventricular tachycardia, what potential complication should the nurse monitor for?
- A Thyroid dysfunction (hypo- or hyperthyroidism)
- B Hypoglycemia from impaired gluconeogenesis
- C Generalized photosensitive skin rash
- D Acute kidney injury and renal failure
Correct answer: Thyroid dysfunction (hypo- or hyperthyroidism)
Amiodarone has many adverse effects including thyroid dysfunction, so monitoring for thyroid problems is essential.
What is the most appropriate instruction for a patient preparing for transcutaneous pacing?
- A “You will not feel anything once the pacing starts.”
- B “You may feel a tapping sensation or chest discomfort; tell us if it becomes intense.”
- C “The device will keep you fully asleep throughout.”
- D “We only use this when you are in a normal rhythm.”
Correct answer: “You may feel a tapping sensation or chest discomfort; tell us if it becomes intense.”
Transcutaneous pacing causes tingling/tapping on chest; the patient should be informed of discomfort and monitored closely.
What is the primary purpose of a direct oral anticoagulant (DOAC) prescribed for a patient with atrial fibrillation?
- A Lower the resting heart rate below 60
- B Prevent stroke from atrial thrombus formation
- C Convert the rhythm back to sinus
- D Improve the left ventricular ejection fraction
Correct answer: Prevent stroke from atrial thrombus formation
In A‐fib, rapid atrial impulses lead to blood stasis and risk of thrombus formation; anticoagulants aim to prevent embolic stroke.
What is the immediate treatment for Torsades de pointes (polymorphic ventricular tachycardia with twisting QRS around baseline)?
- A Intravenous magnesium sulfate
- B Oral digoxin loading dose
- C Continued observation alone
- D Intravenous beta-blocker therapy
Correct answer: Intravenous magnesium sulfate
Torsades is treated emergently with IV magnesium sulfate and sometimes cardioversion rather than waiting.