ALS Drugs Flashcards
Name two shockable rhythms
VF
pulseless VT
name two non-shockable rhythms
PEA
Asystole
in the ALS algorithm, once a shock is delivered (if required), how long do you continue to do CPR for?
2 mins
When a pt has a shockable rhythm, after how many shocks have been delivered should you administer adrenaline and how much?
After the first dose of adrenaline has been administered, how often should you then give further adrenaline?
After 3 shocks give 1mg adrenaline IV.
Give further adrenaline 1mg IV after alternate shocks (every 3-5mins).
When should you give amiodarone in ALS and how much?
If it is a shockable rhythm - Initally give 300mg IV after 3 shocks.
After this, further amiodarone of 150mg IV can be given after 5 shocks.
In a non-shockable rhythm do not give amiodarone.
if a pt is in a non-shockable rhythm what drugs would be administered? When is it started and how much and how often?
Adrenaline 1mg IV given as soon as IV access is achieved.
Repeat every 3-5 mins.
what type of hormone is adrenaline?
catecholamine hormone
where is adrenaline normally synthesised in the body? What cells specifically?
normally synthesised from noradrenaline in the adrenal medulla, specifically the chromaffin cells.
what is the mechanism of action of adrenaline?
alpha and beta adrenoceptor agonist.
Name 5 side effects of adrenaline
headache, reduced appetite, hyperglycaemia, hypertension, peripheral coldness, urinary disorders
name three drugs/drug classes that interact with adrenaline and what the interaction is
amitriptyline (increased effects of adrenaline)
beta blockers - severe HTN
MAO inhibitors (hypertensive crisis). MAO is one of the routes of metabolising adrenaline, therefore, inhibiting their action leads to an increase in adrenaline.
1mg of a 1 in 10,000 solution of adrenaline is used in a cardiac arrest. How many mls would you give of this solution?
1:10,000 means there is 100 micrograms in a ml. so to get 1mg you need to multiply the volume by 10. you will then have 1mg in 10ml. hence, you give 10mls.
once adrenaline has been given in a cardiac arrest, what should it be followed with as a flush?
20ml of 0.9% sodium chloride.
why is there a risk of severe HTN when beta blockers and adrenaline interact?
in the absence of a beta-blocker, adrenaline does not have much effect on mean BP because it has both alpha-adrenergic effects (producing vasoconstriction) and beta-adrenergic effects (producing vasodilation). If a pt is taking a beta-blocker and the pt receives adrenaline, the beta blocker prevents beta-adrenergic vasodilation, leaving unopposed alpha vasoconstriction. cardio-selective beta-blockers are not believed to precipitate hypertensive reactions.
what class of drug does amiodarone belong to?
class III anti-arrhythmic
what is the mechanism of action of amiodarone?
prolongs cardiac AP and delays refractory period.
also inhibits K+ channels involved in repolarisation
name 3 challenges of amiodarone that make it difficult to prescribe
incomplete oral absorption.
large volume of distribution.
extremely long half-life
what do the challenges of amiodarone mean for how it is prescribed?
It means a prolonged loading dose regimen is needed before continuing onto the maintenance dose.
e.g. PO administration is prescribed as 200mg TDS for 1 wk, 200mg BD for 1 week, followed by 200mg OD.
name GI side effects of amiodarone
constipation, N&V, taste disturbance
what side effects can amiodarone have on the eyes?
corneal microdeposits. these are reversible on withdrawal of treatment, associated with night glare, if vision is impaired or optic neuritis/neuropathy develops, amiodarone must be stopped to prevent blindness.
what side effects can amiodarone have on the thyroid?
can cause hypothyroidism by preventing conversion of T4 to T3.
can cause hyperthyroidism as it has a high iodine content which can cause destuctive thyroiditis leading to the release of preformed thyroid hormones and refractory thyrotoxicosis.
what skin reactions can you get with amiodarone?
photosensitive skin rashes, blue-grey discolouration
what side effects does amiodarone have on the liver?
hepatotoxicity.
severely abnormal LFTs or clinical signs of hepatic disease means amiodarone needs to be stopped.
what should be suspected in a pt on amiodarone with a new onset SOB or cough?
progressive pneumonitis and lung fibrosis
what side effects can amiodarone have on the heart?
Proarrhythmic effects:
- bradycardia
- heart blocks
- dysrhythmias
- prolonged QT interval