Bradycardia

Question 1

What is bradycardia?

Answer 1

A heart rate of less than 60 bpm in adults.

Question 2

What are the clinical features of symptomatic bradycardia?

Answer 2

slow heart rate < 60 bpm
hypotension
dizziness, mental status changes, N/V

Question 3

What is the differential diagnosis for bradycardia?

Answer 3

1. CNS: incr ICP, incr vagal stimulation, spinal shock
2. CV: MI, SSS, AV block
3. Pulm: hypoxemia
4. metabolic: acidosis, hypothermia
5. endocrine: hypothyroidism, adrenal insufficiency
6. drugs: beta-blockers, anesthetics, potassium, calcium, digoxin

Question 4

What are the CNS causes of bradycardia?

Answer 4

increased ICP
vagal stimulation
spinal shock

Question 5

What are cardiovascular causes of bradycardia?

Answer 5

myocardial ischemia/infarction
sick sinus syndrome
AV blocks

Question 6

What are pulmonary causes of bradycardia?

Answer 6

hypoxemia

Question 7

What are metabolic causes of bradycardia?

Answer 7

acidosis

hypothermia

Question 8

What are endocrine causes of bradycardia?

Answer 8

hypothyroidism

adrenal insufficiency

Question 9

What are common drugs that cause bradycardia?

Answer 9

beta-blocks
anesthetics
potassium
calcium
digoxin

Question 10

What is the management of bradycardia?

Answer 10

1. Verify the rate and rhythm
2. maintain airway
3. confirm rhythm on ECG
4. check BP
5. check with surgery team to see if surgical cause (visceral traction in pelvis/abdomen)
6. if signs of poor perfusion–>atropine 0.5mg, epinephrine 10 to 20 mcg boluses, epinephrine infusion, if refractory to meds–>transcutaneous pacing
7. if only mild symptoms–>atropine 0.4mg IV, ephedrine 5 - 10mg PRN, glycopyrrolate 0.2mg IV
8. if no symptoms–> observe and monitor
9. Identify and treat correctable cause