MICA Pharmacology Flashcards
Adenosine
Pharmacology
6mg in 2ml
A naturally occurring purine nucleoside found in all body cells
Actions
- slows conduction velocity though the AV node, resulting in termination of re-entry circuit activity within or including the AV nodal pathway
Adenosine
Indications
- AVRNT with adequate or inadequate perfusion but not deteriorating rapidly
- AVRT and assoc WPW syndrome or other accessory tract SVT with adequate or inadequate perfusion but not deteriorating rapidly
Adenosine
Contraindications
- Second degree or third degree AV block (may produce prolonged sinus arrest/AV blockage)
- AF
- Atrial flutter
- Ventricular tachyarrhythmias
- Known hypersensitivity.
Adenosine
Precautions
- Adenosine may provoke bronchospasm in the asthmatic patient
- Adenosine is antagonist by methlyanthines (caffeine, theophyllines drug used of COPD and asthma). The drug may not be effective in patients with large caffeine intake or those on high doses of theophylline medications
Adenosine
Side effects
Usually brief and transitory
- Transient arrhythmia (including asystole, bradycardia, or ventricular ectopy) may be experienced following reversion
- Chest pain
- Dyspnoea
- Headache or dizziness
- Nausea
- Skin flushing
Adenosine
Doses
If BP <90
6mg IV
Repeat @ 2/60 12mg IV. One further dose given at 2/60
Amiodarone
Pharmacology
150mg in 3ml
Class III anti-arrhythmic agent
Amiodarone
Indications
- VF/ pulseless VT refractory to cardioversion
2. Sustained or recurrent VT
Amiodarone
Contrainidcations
- VF/pulseless VT refractory to cardioversion - nil significance in this setting
- VT contra if pregnant
- TCA OD
- Do not administer if VT follows ondansetron administration
Amiodarone
Precautions
Nil of significance
Amiodarone
Side effects
- Hypotension
2. Bradycardia
Amiodarone
Special notes
Onset: 2min
Peak: 20min
Duration: 2hours
Incompatible with normal saline. Must be diluted with glucose 5%
Amiodarone
Dose
Cardiac arrest
After 3 DCCS 300mg IV/IO
After 5 DCCS 150mg IV/IO
Conscious VT stable
- 5mg/kg IV max 300mg over 20/60
Atropine
Pharmacology
600mcg in 1ml
1200mcg in 1ml
An anticholinergic agent
Actions
- inhibits the actions of acetylcholine on post ganglionic cholinergic nerves at the neuro-effector site e.g. as a vagal blocker and allows sympathetic effect to;
- increase HR to increasing SA node firing rate
- increase the conduction velocity through AV node
- antidote to reverse the effects of cholinesterase inhibitors (organophosphate insecticides) at the post ganglionic neuro-effector sites of cholinergic nerves to:
- reduce the excessive salivary, sweat, GIT and bronchial secretions and
- relax smooth muscles
Atropine
Indications
- Unstable bradycardia
- Organophosphate OD with excessive cholinergic effects
- Hypersalivation as a side effect of ketamine
Atropine
Contraindications
Previous heart transplant
Atropine
Precautions
- Atrial flutter
- AF
- Myocardial infarction
- Do no increase HR above 100 except children under 6years
- Glaucoma
Atropine
Side effects
- Tachycardia
- Palpitations
- Dry mouth
- Dilated pupils
- Visual blurring
- Retention of urine
- Confusion, restlessness (in large doses)
- Hot, dry skin (in large doses)
Atropine
Special notes
Onset <2min
Peak <5min
Duration 2-6hours
10ml flush of saline MUST be administered after atropine if adrenaline is also going to be administered