NSG210 Hinkle Chapter 22 Outline - Arrhythmias and Conduction Problems

Source context: Hinkle & Cheever / Brunner & Suddarth Medical-Surgical Nursing, 15th ed., Chapter 22: Management of Patients with Arrhythmias and Conduction Problems. Note: the course reading sheet may list arrhythmias as Ch. 23, so verify against the exact PDF/table of contents your instructor is using.

1. Big picture

Arrhythmias are disturbances in the heart’s electrical impulse formation, impulse conduction, or both. The nursing priority is not just naming the rhythm, but deciding whether the rhythm is reducing cardiac output or creating risk for deterioration.

Core question for every rhythm:

Is the patient stable or unstable?
Is cardiac output adequate?
Is perfusion adequate?
Does the patient need monitoring, medication, cardioversion, pacing, defibrillation, or advanced intervention?

2. Normal conduction review

Normal impulse pathway:

SA node
Atria
AV node
Bundle of His
Right and left bundle branches
Purkinje fibers
Ventricular myocardium

Key ECG pieces:

ECG part	Meaning
P wave	Atrial depolarization
PR interval	Time from atrial depolarization through AV-node conduction
QRS complex	Ventricular depolarization
ST segment	Early ventricular repolarization; should be near baseline
T wave	Ventricular repolarization
QT interval	Ventricular depolarization through repolarization

3. How to read a rhythm strip

Use a consistent method:

Check rate: atrial and ventricular if different.
Check rhythm regularity: regular or irregular.
Check P waves: present, absent, inverted, sawtooth, fibrillatory.
Check PR interval: normal, prolonged, variable, absent.
Check QRS width: narrow or wide.
Check QT interval if relevant.
Compare rhythm to the patient: blood pressure, mental status, chest pain, dyspnea, pulse quality, skin signs, urine output.

4. Causes and risk factors

Arrhythmias may result from:

myocardial ischemia or infarction;
heart failure or cardiomyopathy;
hypoxia;
electrolyte imbalance, especially potassium, magnesium, and calcium;
acid-base imbalance;
medication effects or toxicity, especially digoxin and antiarrhythmics;
sympathetic stimulation, pain, fever, anxiety, sepsis;
structural heart disease;
post-procedure or post-operative stress;
conduction-system disease in older adults.

5. Nursing assessment priorities

Assess for decreased cardiac output:

hypotension;
altered mental status;
dizziness or syncope;
chest pain;
dyspnea;
cool, clammy skin;
weak pulses;
decreased urine output;
new fatigue or activity intolerance.

Important point: a rhythm that looks dramatic on the monitor is less important than whether the patient is perfusing.

6. Sinus rhythms

Normal sinus rhythm

SA node controls rhythm.
Regular rhythm.
P wave before each QRS.
Normal PR interval.

Sinus bradycardia

Rate below normal.
May be normal in athletes or during sleep.
Concerning if symptomatic: hypotension, dizziness, syncope, chest pain, confusion.
Treatment may include atropine and pacing if unstable and unresponsive.

Sinus tachycardia

Rate above normal from SA node.
Often a response to another problem: pain, fever, hypoxia, anxiety, bleeding, dehydration, heart failure, sepsis.
Treat the underlying cause.

7. Atrial arrhythmias

Premature atrial contractions

Early atrial beat.
Often benign but can reflect atrial irritability.
Monitor frequency and triggers.

Supraventricular tachycardia

Rapid rhythm usually with narrow QRS.
May cause palpitations, dizziness, chest discomfort, hypotension.
Treatment may include vagal maneuvers, adenosine, rate-control medications, or cardioversion if unstable.

Atrial flutter

Organized atrial rhythm; classic sawtooth flutter waves.
Ventricular response depends on AV conduction ratio.
Risk: reduced cardiac output and thromboembolism.
Management: rate control, rhythm control/cardioversion, anticoagulation depending on stroke risk.

Atrial fibrillation

Chaotic atrial activity; no organized P waves.
Irregularly irregular ventricular rhythm.
Major risks: decreased cardiac output and embolic stroke.
Management goals:
- control ventricular rate;
- restore rhythm if appropriate;
- prevent stroke with anticoagulation when indicated;
- treat triggers such as hypoxia, electrolyte imbalance, ischemia, infection, or heart failure.

High-yield safety point: in atrial fibrillation with a very fast, irregular, wide-complex rhythm, suspect an accessory pathway such as WPW and escalate quickly.

8. Junctional rhythms

Junctional rhythms originate near the AV junction when the SA node fails or conduction is disrupted.

Possible features:

absent, inverted, or retrograde P waves;
P waves may appear before, during, or after QRS;
usually narrow QRS unless another conduction problem exists.

Clinical significance depends on rate and perfusion.

9. Ventricular arrhythmias

Premature ventricular contractions

Early ventricular beat with wide, bizarre QRS.
Can be occasional or frequent.
Concerning patterns include frequent PVCs, multifocal PVCs, couplets, runs, or PVCs in a patient with ischemia/electrolyte imbalance.

Ventricular tachycardia

Rapid ventricular rhythm, usually wide-complex.
Can occur with or without a pulse.
Sustained VT can quickly reduce cardiac output.
If pulseless: treat like ventricular fibrillation with immediate defibrillation/CPR.
If unstable with a pulse: synchronized cardioversion is usually needed.
Medications may include amiodarone or other antiarrhythmics depending on protocol.

Ventricular fibrillation

Chaotic ventricular activity.
No effective cardiac output.
Patient is pulseless and unresponsive.
Immediate CPR and defibrillation are required.

Asystole / pulseless electrical activity

Asystole: no organized electrical activity.
PEA: organized electrical activity without a pulse.
Defibrillation does not correct asystole or PEA; treatment focuses on CPR, epinephrine, and reversible causes.

10. Conduction blocks

First-degree AV block

PR interval prolonged but every P wave conducts to QRS.
Usually monitor unless symptomatic or medication-related.

Second-degree AV block type I / Wenckebach

PR interval progressively lengthens until a QRS is dropped.
Often transient but monitor symptoms and causes.

Second-degree AV block type II

Dropped QRS complexes without progressive PR lengthening.
More dangerous; can progress to complete heart block.
May require pacing.

Third-degree AV block / complete heart block

No atrial impulses conduct to ventricles.
P waves and QRS complexes occur independently.
Ventricular rate may be slow; cardiac output may drop.
Usually requires pacing if symptomatic or unstable.

11. Medication concepts

Know medication goals more than just names:

Rate control

Used especially for atrial fibrillation/flutter or some SVTs.

beta-blockers;
calcium channel blockers such as diltiazem/verapamil;
digoxin in selected patients.

Nursing concerns:

monitor blood pressure and heart rate;
watch for bradycardia and hypotension;
check apical pulse when relevant;
digoxin toxicity risk increases with hypokalemia and renal impairment.

Rhythm control / antiarrhythmics

May include medications such as amiodarone or other class-specific agents.

Nursing concerns:

monitor ECG and QT interval when relevant;
monitor electrolytes;
watch for proarrhythmia;
know drug-specific toxicities.

ACLS/emergency medications

atropine for symptomatic bradycardia;
adenosine for certain regular narrow-complex SVTs;
epinephrine during cardiac arrest;
amiodarone for shock-refractory ventricular fibrillation/pulseless VT depending on protocol.

Anticoagulation

Important in atrial fibrillation/flutter because stagnant atrial blood can form clots and cause stroke.

warfarin;
direct oral anticoagulants such as factor Xa inhibitors or direct thrombin inhibitors;
heparin/LMWH depending on setting.

Nursing concerns:

bleeding risk;
fall risk;
renal dosing for some agents;
patient teaching and adherence.

12. Electrical therapies

Cardioversion

Synchronized shock.
Used for unstable tachyarrhythmias with a pulse or planned conversion of some rhythms.
Shock is timed with the cardiac cycle to reduce risk of inducing VF.

Defibrillation

Unsynchronized shock.
Used for ventricular fibrillation or pulseless ventricular tachycardia.
Safety: ensure no one is touching the patient before shock.

Pacing

Used for symptomatic bradycardia or conduction block.

Types:

transcutaneous pacing for emergency temporary support;
transvenous temporary pacing;
permanent pacemaker.

Monitor for:

capture;
sensing;
heart rate/rhythm;
hemodynamic response;
insertion-site bleeding/infection for implanted devices.

13. Pacemakers

Purpose: maintain adequate heart rate when the intrinsic conduction system fails.

Nursing priorities after insertion:

monitor ECG continuously;
assess insertion site for bleeding, hematoma, infection;
assess for pacemaker malfunction;
limit arm movement on affected side as ordered after implantation;
teach patient about follow-up and electromagnetic precautions.

Possible problems:

failure to capture;
failure to sense;
infection;
bleeding/hematoma;
lead displacement;
battery failure over time.

14. Implantable cardioverter-defibrillator

Purpose: detect and terminate life-threatening ventricular tachycardia or ventricular fibrillation.

Key teaching:

ICD treats dangerous ventricular rhythms, not ordinary MI, atrial fibrillation, or bradycardia.
Shocks may be painful/frightening but can be lifesaving.
Report shocks according to provider instructions, especially multiple shocks or symptoms.
Avoid strong electromagnetic fields.

15. Ablation and procedural therapies

Electrophysiology study

Used to identify conduction pathways and provoke/map dysrhythmias.

Catheter ablation

Destroys small areas of cardiac tissue that generate or conduct abnormal rhythms.

Nursing care after ablation:

monitor rhythm for recurrence;
assess vascular access site;
monitor bleeding and distal pulses;
maintain ordered activity restrictions.

Maze procedure

Surgical procedure used for atrial fibrillation in selected patients, often with cardiac surgery.

Goal: create scar pathways that block abnormal conduction and restore organized atrial rhythm.

16. Patient education

Teach patients to:

report palpitations, dizziness, syncope, chest pain, dyspnea;
take medications exactly as prescribed;
avoid stopping beta-blockers or antiarrhythmics abruptly unless instructed;
monitor pulse if instructed;
understand anticoagulation bleeding precautions;
attend device follow-up appointments;
know when to seek emergency care.

17. NCLEX/classroom priorities

Highest-yield ideas:

Assess the patient first, not just the monitor.
Unstable tachycardia with a pulse usually needs synchronized cardioversion.
Pulseless VT/VF needs CPR and defibrillation.
Symptomatic bradycardia may need atropine and pacing.
Atrial fibrillation raises stroke risk and often requires anticoagulation.
Third-degree AV block means atria and ventricles are dissociated; pacing may be needed.
Pacemaker/ICD patients need rhythm monitoring and insertion-site checks.
Electrolytes, hypoxia, ischemia, and medication toxicity are common reversible causes.

18. One-line summary

Chapter 22 is about recognizing abnormal cardiac rhythms, judging whether they are harming perfusion, and knowing the nursing/medical responses: monitoring, correcting causes, rate/rhythm medications, anticoagulation, cardioversion, defibrillation, pacing, ICDs, and ablation.