Bradycardia

Question 1

Why is atropine unlikely to be effective in Mobitz II and CHB?

Answer 1

Atropine increases SA node firing rate, and AV conduction speed. If the HB is below the site of the AVN, atropine will be ineffective.

Question 2

4 indicators of unstable bradycardia

Answer 2

1. Less than adequate perfusion
2. HR <40 with APO
3. Runs of VT/ ventricular escapes
4. HR <20

Question 3

Firstline treatment + repeats for symptomatic bradycardia

Answer 3

Atropine 600mcg IV.
Rpt 1200mcg at 3-5mins if inadequate response.
Then continue 600mcg at 3-5mins if adequate response, max 3000mcg.

Question 4

Second line treatment for symptomatic bradycardia

Answer 4

After 600+1200mcg Atropine, inadequate response then:
Adrenaline infusion starting 5mcg/min, increase to 10mcg/min if required

Question 5

When is transthoracic pacing indicated?

Answer 5

Extremely poor perfusion:
- Unconscious/altered conscious
- HR <50
- BP <60

Question 6

Transthoracic pacing medications, commencing mA

Answer 6

Midazolam 1-2mg IV, Fentanyl 50mcg IV.
Commence at 30mA, HR 70bpm

Question 7

Adrenaline infusion preparation

Answer 7

3mg Adrenaline, 47mL Normal Saline.
1mL/hr = 1mcg/min