SVT Flashcards
1
Q
Adenosine indications
A
SVT
2
Q
Adenosine MOA
A
- Agonist of adenosine receptors - in heart activating these = reduced frequency of spontaneous depolarisations (automaticity) and increase resistance to repolarisations (refractoriness). = slow sinus rate and conduction velocity and increase AVN refractoriness.
- increasing refractoriness breaks re-entry circuit and allows cardioversion.
- if circuit doesnt involve AVN e.g atrial flutter = no cardioversion
3
Q
half life of adenosine
A
10s in plasma
4
Q
SE Adenosine
A
- bradycardia
- asystole
- skinking feeling
- SOB
- Sense of impending doom
5
Q
CI to adenosine
A
hypotentsion coronary ischaemia decompensated HF - asthma (bronchospasm risk) relative CI - COPD - Heart transplant
6
Q
interactions of adenosine
A
- dipyridamole = antiplt agent. blocks cellular uptake of adenosine and prolongs it seffects. so must half dose of adenosine.
- theophyllyine and aminophylline = competitive antagonists of adenosine receptor and reduces its effects. = may need higher dose
7
Q
where should you write an adenosine prescription on the chart
A
- once only . 6mg IV
- if ineffective give 12mg IV
- If using central line = 3mg initially
8
Q
how should you administer adenosine
A
- large bore cannula (18G green) or bigger. site as proximally as possible e.g. antecubital fossa
- give as rapid injection and then flush e.g. 20ml of 0.9% Na cl
9
Q
how must you monitor a patient on adenosine
A
- continuous cardiac rhythm strip
