ACLS — Advanced Cardiovascular Life Support — All Questions

A patient collapses in witnessed VF arrest and a defibrillator is immediately available. The highest priority is to:

• a.Establish IV access and give epinephrine
• b.Intubate the patient first
• c.Shock now, then resume CPR✓
• d.Give amiodarone before any shock

When VF is witnessed with a defibrillator immediately available, the 2025 Guidelines say defibrillation can be performed immediately; compressions resume at once after the shock. Drugs come after initial CPR and shocks fail.

The monitor shows an organized rhythm but the patient has no pulse (PEA). Management includes:

• a.Immediate defibrillation
• b.Synchronized cardioversion
• c.Adenosine 6 mg rapid IV push
• d.CPR, epinephrine and a cause search✓

PEA is nonshockable: high-quality CPR, early epinephrine and a search for reversible causes such as hypovolemia, hypoxia, tamponade, pulmonary embolism, electrolyte problems and toxins.

Immediately after delivering a defibrillation shock, the team should:

• a.Check a pulse for 30 seconds
• b.Resume compressions right away✓
• c.Reanalyze the rhythm at once
• d.Give two breaths before compressions

Immediate resumption of compressions after a shock shortens the perishock pause and improves the compression fraction; the rhythm is rechecked after about 2 minutes of CPR.

A patient on telemetry develops VF while pads are already on. What is the first treatment?

• a.Intubation
• b.Immediate defibrillation✓
• c.Two minutes of CPR first
• d.Epinephrine 1 mg IV

When VF is monitored or witnessed with a defibrillator already applied, defibrillation can be performed immediately; CPR first is for unmonitored arrest.

What biphasic energy should be used for adult VF when the manufacturer's setting is unknown?

• a.The device's lowest setting
• b.No shock until it is known
• c.50 J for every shock
• d.The device's maximum setting✓

The optimal biphasic energy is best deferred to the manufacturer; when that setting is unknown, another approach is to use the maximum setting for that device.

Why are single shocks followed by CPR preferred over stacked shocks in most arrests?

• a.Stacked shocks cause asystole
• b.Single shocks need no pads
• c.Stacked shocks are too weak
• d.Shorter pauses and better survival✓

A single-shock strategy shortens CPR interruptions and was associated with improved survival to admission and discharge compared with stacked shocks.

What term do the 2025 Guidelines use for VF that remains after three or more consecutive shocks?

• a.Stable VF
• b.Terminal VF
• c.Persisting VF/pVT✓
• d.Fine VF

The Guidelines propose "persisting VF/pVT" for VF/pVT remaining after three or more shocks when it is uncertain whether the shock failed or VF recurred.

What is the 2025 position on double sequential defibrillation for refractory VF?

• a.Not yet established✓
• b.Harmful and banned
• c.First-line after one shock
• d.Mandatory after three shocks

The top-ten list states the usefulness of vector change and double sequential defibrillation for shock-refractory VF has not been established and needs further investigation.

In asystole, when is epinephrine given?

• a.Never in asystole
• b.After 20 minutes of CPR
• c.As soon as possible✓
• d.After three shocks

Earlier epinephrine is associated with ROSC, and its benefit is greater in nonshockable rhythms, so it is given as soon as feasible in asystole or PEA.

A patient in PEA has a history of end-stage kidney disease and missed dialysis. Which cause should the team consider?

• a.Opioid overdose
• b.Hypothermia
• c.Hyperkalemia✓
• d.Tension pneumothorax

Impaired kidney function is a risk factor for hyperkalemia, which can cause life-threatening arrhythmias and arrest; treatment may begin on suspicion without lab confirmation.

Which is true about pacing in asystolic cardiac arrest?

• a.It is first-line therapy
• b.It replaces epinephrine
• c.It does not improve ROSC or survival✓
• d.It works if started within 10 minutes

Evidence shows pacing during cardiac arrest does not improve ROSC or survival and may interrupt CPR.

An EMS crew witnessed a patient's collapse and has been resuscitating for 20 minutes without ROSC. Does the universal termination rule apply?

• a.Only if an AED shocked the patient
• b.Yes; 20 minutes is enough on its own
• c.Yes, if the ETCO2 is below 20
• d.No; the arrest was EMS-witnessed✓

The UTOR rule requires that the arrest was not witnessed by EMS professionals, no shock was delivered and there was no ROSC; an EMS-witnessed arrest does not meet it, and ETCO2 is not used alone.

For which group are termination-of-resuscitation rules NOT validated?

• a.BLS-only EMS agencies
• b.Patients with trauma✓
• c.Tiered EMS systems
• d.Adults with cardiac arrest in the community

TOR rules are inappropriate for populations in which they have not been validated, such as patients with overdose, trauma or in-hospital arrest.

How should an ETCO2 below 10 mm Hg after 20 minutes of ALS resuscitation be used?

• a.As a reason to shock
• b.As one factor, never alone✓
• c.As an automatic stop signal
• d.As proof of ROSC

A low ETCO2 after 20 minutes is strongly but not perfectly predictive of futility, and the Guidelines say ETCO2 should not be used in isolation to end resuscitation.

Which intervention for a suspected massive pulmonary embolism arrest do the Guidelines discuss?

• a.Atropine
• b.Systemic fibrinolysis✓
• c.Synchronized cardioversion
• d.Adenosine

Treatments for arrest from PE include systemic and catheter-guided fibrinolysis, surgical and mechanical embolectomy, and ECMO.

Ultrasound during arrest shows a large pericardial effusion. How do the Guidelines frame this finding?

• a.An incidental finding to ignore
• b.Proof of VF
• c.A potentially reversible cause✓
• d.A reason to stop CPR at once

POCUS during arrest can help identify potentially reversible causes such as cardiac tamponade and effusion, provided it does not interrupt CPR.

A physician wants to give high-dose epinephrine every minute during an arrest. What does the evidence show?

• a.Better neurologic outcomes
• b.Required after 10 minutes
• c.Clear survival benefit
• d.No advantage; may harm✓

High-dose epinephrine studies gave mixed results, and a registry study found dosing more frequently than the standard interval may be harmful.

What proportion of VF seen after shocks reflects recurrence rather than shock failure?

• a.None
• b.About 20%
• c.About 5%
• d.About 80%✓

The Guidelines report that about 80% of VF seen at post-shock rhythm checks is recurrence after successful termination, not true shock failure.

A hypothermic patient in VF does not respond to a shock. What caution applies?

• a.Shocks should be given every 30 seconds
• b.Too many shocks may injure it✓
• c.Defibrillation never works when cold
• d.Stop CPR until warm

Defibrillation before rewarming can succeed, but the cold heart responds less and excessive attempts may lead to myocardial injury; rewarming continues with CPR.