Dysrhythmias 2

Question 1

What is dysrhythmia

Answer 1

Abnormality of cardiac rhythm

Problem with impulse generation or conduction

Why is it significant?

Question 2

Abnormal HR =

Answer 2

Abnormal CO

Question 3

What causes dysrhythmias?

Answer 3

1. Inappropriate Automaticity
2. Triggered activity
3. Re-entry

Question 4

Dysrhythmias: Inappropriate Automaticity

Answer 4

A cell initiates action potential when it isn’t supposed to.
(Myocardial ischemia, K+)

Question 5

Dysrhythmias: Triggered activity

Answer 5

An extra impulse is generated during or just after repolarization
(meds, SNS stimulation)

Question 6

Dysrhythmias: Re-entry

Answer 6

Cardiac impulse in one part of the heart continues to depolarize after the main impulse has finished
(Myocardial ischemia, K+)

Question 7

Sinus means…

Answer 7

Triggered by SA Node

Question 8

Sinus Bradycardia

Answer 8

Regular, rate < 60bpm

Rhythm: Normal

Normal PR interval + QRS

Just slower!

Question 9

Sinus Bradycardia: Causes

Answer 9

• Hyperkalemia (slows depolarization)
• Vagal response
• Digoxin toxicity
• Late hypoxia
• Medications
• Myocardial Infarction (ischemia around SA node)

Question 10

Sinus Bradycardia: Clinical Manifestations

Answer 10

• Lightheadedness or Dizzy
  (esp. on exertion)
• Easy Fatigability
• Syncope
• Dyspnea
• Chest pain or discomfort
• Confusion

*All has to do with lack of OXYGEN to cells

Question 11

Sinus Bradycardia: Treatment

Answer 11

Could be normal (athletes)

Atropine: anticholinergic

If drugs don’t work: Pacemaker

Question 12

Sinus Tachycardia

Answer 12

Rate: 100-150 bpm

Rhythm: Normal

Normal PR interval + QRS

P waves similar (may be partially hidden)

Question 13

Sinus Tachycardia: Causes

Answer 13

• Catecholamines: exercise, pain, strong emotions
• Fever
• Fluid volume Deficit (dehydration)
• Medications
• Substances
• Hypoxia (early)

Question 14

Sinus Tachycardia: Treatment

Answer 14

Based on Cause:

• Hypovolemia: Fluids
• Fever: Antipyretics
• Pain: Analgesics

Beta blockers to reduce HR and myocardial oxygen consumption

Question 15

Paroxysmal Supraventricular Tachycardia (PSVT)

Answer 15

Tachycardia originating above the ventricles

HR 150-250

Originates: AV node

Usually NO “P” wave
-if present they look abnormal

QRS normal

Question 16

Paroxysmal Supraventricular Tachycardia (PSVT): Characteristics

Answer 16

Usually caused by a Re-entry phenomenon

Typically begins and ends suddenly

Often described as “feeling like my heart is racing”

Question 17

PSVT: Causes

Answer 17

Over exertion
Emotional stress
Stimulants
Digitalis Toxicity
Rheumatic heart disease
CAD
WPW (Wolff-Parkinson-White)
Right-sided HF

Question 18

PSVT: Symptoms

Answer 18

Palpitations
Chest pain
Fatigue
Lightheadedness or dizzy
Dyspnea

Question 19

Premature Atrial Contractions (PAC’s)

Answer 19

Early P waves that usually look a little different

Normal PR interval

QRS does follow the PAC

Usually has no consequences, but if frequent indicates that patient at high risk for other dysrhythmias (usually AFIB)