Cardiac Drugs

Question 1

ADENOSINE in SVT

Answer 1

AV (and SA) blocker

Onset 10secs
Duration 10secs

ADVERSE:
- Flushing
- Doom
- Chest pain
- Bronchospasm

CONTRAINDICATIONS
- X Severe asthma/COPD
- X 2nd and 3rd degree block
- Cardiac transplant

Dose:
100microg/kg –> 200 –> 200
(ie. 6mg –> 12 –> 12)

Question 2

VERAPAMIL in SVT

Answer 2

Non-dihydro CCB
AV blocker
Negative inotropy
Vasodilation (some)

Equally as effective as adenosine for SVT.

Onset: 5-10mins

Dose: 2.5 - 5mg IV, repeat 30 minutely to max 30mg

ADVERSE
- Hypotension
- Bradycardia
- AV block
- Flushing
- Nausea

CONTRAINDICATIONS
- Hypotension
- CCF
- 2nd or 3rd degree block
- 1st trimester

Question 3

ATROPINE in bradycardia

Answer 3

Anticholinergic, vagal-blocker and positive chromotrope

Most effective ABOVE the node- ie. vagal reflexes, cholinergics

Likely to fail BELOW the node- ie. AV block, ventricular bradycardias.
….isoprenaline/pacing better here.

Dose: 20microg/kg, repeated 5-10min
IV, IM, ETT (5x dose)

ADVERSE
- Anticholinergic *(blind, red, mad etc.)

CONTRAINDICATIONS
- Glaucoma
- Ileus/ GI obstruction

Question 4

ISOPRENALINE in bradycardia

Answer 4

Inodilator
B1 and B2
+ inotropy, chromotropy
Vasodilation

Useful in bradycardias
(adrenaline still preferred in ischaemia: coronary perfusion)

Dose:
10-20microg bolus
2-10 mic/min infusion
Safe to run peripherally

ADVERSE
- Tachycardia
- Hypotensio (vasodilation)
- Arrhythmia

CONTRAINDICATIONS
- Digoxin toxicity (arrrhythmia ++)
- Active ischaemia (adrenaline better)

Question 5

Main antiplatelets:

Answer 5

COX inhibitor (activation)
ASPIRIN

ADP inhibitor (aggregation)
CLOPIDOGREL
TICAGRELOR
PRASUGEL

IIbIIIa Inhibitor
TIROFIBAN
ABCIXIMAB

Phosphodiesterase inhibitor
DIPYRIDAMOLE