Cardiac Rhythm Disturbances (General Approach to Bradycardia)

Question 1

What are the instability indicators in a patient with cardiac dysrhythmias? (3)

Answer 1

1. Hypotension: SBP <90mmHg (<12kPa)
2. Systemic hypoperfusion (Altered Mental Status, Chest pain [coronary ischemia], Dyspnea [rales, edema, desat])
3. Extreme tachycardia (220-240 in adult)

Table 18-1

instability in dysrhythmia indicates impaired perfusion leading to vital organ dysfunction and high potential for cardiac arrest

Question 2

Categorize Bradydysrhythmias (2)

Answer 2

1. Bradycardia (Atrium and ventricle at the same rate)
2. AV block (ventricles slower than atrium)

Question 3

What are the most common bradycardia rhythms in descending order? (3)

Answer 3

1. Sinus
2. Junctional
3. Idioventricular

Question 4

In which cases can Afib in Slow ventricular rate or flutter be seen? (2)

Answer 4

1. Sinus sick syndrome
2. AV blocking medications

Question 5

Most common bradycardia rhythm in unstable patients (2)

Answer 5

1. 3rd deg AV block
2. 2nd deg AV block

Question 6

Most common AV block in descending order in stable patients (3)

Answer 6

1. 2nd Degree Type I
2. 3rd Degree
3. 2nd Degree Type II

Question 7

When is emergent bradyarrythmia treatment indicated? (2)

Answer 7

1. HR <50-60 + hypotension
2. Infranodal conduction system structural disease

Question 8

Drugs for bradycardia (4)

Answer 8

1. Atropine
2. Dopamine
3. Epinephrine
4. Glucagon

Question 9

Atropine MOA

Answer 9

Enhances SA node automaticity

Question 10

In which cases is atropine effective? (2)

Answer 10

1. Sinus bradycardia
2. Junctional rhythms

Question 11

In which cases is atropine ineffective, but not harmful? (3)

Answer 11

1. Idioventricular rhythms
2. 2nd Degree AV block
3. 3rd Degree AV block

Question 12

Glucagon MOA and indication

Answer 12

Stimulates chronotropic and inotropic cardiac activity independent of B adrenergic receptors

brady secondary to cardiotoxicity from B blockers or CCB

Question 13

Most appropriate pacing method in an acutely symptomatic patient

Answer 13

Transcutaneous pacing

Question 14

Steps in cardiac pacing (4)

Answer 14

1. Establish electrical capture
2. Determine mechanical capture (palpable pulse with paced beat + sustained improvement in perfusion)
3. Adjust paced rate
4. Establish energy required to achieve sustained electrical pacing

Question 15

Atropine dose

Answer 15

0.5-1mg TIV ever 3-5 mins
max dose: 3mg

Question 16

Atropine is MOST effective for?

Answer 16

Bradydysrhythmias secondary to sinus and higher AV nodal disease

Question 17

Dopamine dose

Answer 17

IV infusion rate of 2-20 micrograms/kg/min

Question 18

Epinephrine dose

Answer 18

IV infusion rate of 2-10 micrograms/min

Question 19

Glucagon dose

Answer 19

3-10mg over 1-2 min bolus

IV infusion rate 1-5mg/h continuous

Question 20

Limiting Side effects of glucagon

Answer 20

1. Nausea and vomiting
2. Tachyphylaxis