ACLS — Advanced Cardiovascular Life Support — All Questions
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What is the correct dose and interval of epinephrine during adult cardiac arrest?
- a.0.5 mg IV/IO every 10 minutes
- b.1 mg IV/IO every 3 to 5 minutes✓
- c.3 mg IV/IO given once
- d.1 mg IV/IO every minute
Epinephrine in cardiac arrest is 1 mg IV/IO every 3 to 5 minutes. Its alpha-adrenergic vasoconstriction raises aortic diastolic pressure and thereby coronary perfusion pressure. In non-shockable rhythms (asystole/PEA), give epinephrine as soon as feasible; in shockable rhythms (VF/pVT), give it after the first shock or two fail to convert the rhythm.
For refractory ventricular fibrillation or pulseless VT, what is the first dose of amiodarone?
- a.150 mg IV/IO bolus
- b.300 mg IV/IO bolus✓
- c.1 mg IV/IO bolus
- d.6 mg IV/IO bolus
The first amiodarone dose for shock-refractory VF/pVT is 300 mg IV/IO push, followed by a second dose of 150 mg if needed. Amiodarone is an antiarrhythmic given after epinephrine and continued defibrillation attempts have not converted the rhythm. Lidocaine (1-1.5 mg/kg first dose) is an acceptable alternative.
A stable patient has a regular narrow-complex SVT and vagal maneuvers have failed. What is the first dose of adenosine?
- a.6 mg rapid IV push, followed by a 12 mg dose if needed✓
- b.1 mg slow IV push
- c.0.5 mg IV push
- d.300 mg IV bolus
Adenosine is given 6 mg by rapid IV push (followed immediately by a saline flush), and if the rhythm does not convert, a 12 mg dose may follow. Its very short half-life briefly blocks AV nodal conduction, which can terminate a re-entrant SVT. It is used only for stable, regular, narrow-complex tachycardia after vagal maneuvers fail.
What is the atropine regimen for symptomatic bradycardia in adults?
- a.0.5 mg IV once, maximum 1 mg
- b.1 mg IV every 3 to 5 minutes, maximum total 3 mg✓
- c.3 mg IV given once
- d.6 mg rapid IV push
For symptomatic bradycardia, atropine is 1 mg IV every 3 to 5 minutes up to a maximum total dose of 3 mg. Atropine blocks vagal tone to increase heart rate. If it is ineffective, move to transcutaneous pacing or a dopamine or epinephrine infusion. (Note the atropine dose was updated to 1 mg in current guidelines, replacing the older 0.5 mg.)