3.2 Cardiac Arrest & CPR

Cardiac arrest is the highest-acuity scenario in the Cardiology and Resuscitation domain. The exam tests whether you can deliver and lead high-quality cardiopulmonary resuscitation (CPR), integrate the automated external defibrillator (AED), and function within a resuscitation team using AEMT-level skills.

The Chain of Survival

Survival from sudden cardiac arrest depends on a series of time-critical actions. Each link is interdependent — a weak link reduces the whole chain's effectiveness.

• Early recognition and activation of emergency response.
• Early high-quality CPR with an emphasis on chest compressions.
• Early defibrillation for shockable rhythms.
• Advanced resuscitation interventions delivered by the responding team.
• Post-arrest care and transport to definitive care.

High-Quality CPR

The single biggest factor an AEMT controls is compression quality. The exam consistently rewards answers that protect compression quality.

For pediatric and infant patients, the principles are the same but depth and hand technique differ by patient size; depth is roughly one-third the anterior-posterior chest diameter. Always follow current resuscitation guidelines and local protocol for exact ratios and techniques.

The AED

The AED analyzes the rhythm and advises a shock for shockable rhythms — ventricular fibrillation (V-fib) and pulseless ventricular tachycardia (V-tach). Asystole and pulseless electrical activity (PEA) are not shockable; for those, the priority is high-quality CPR and treating reversible causes within scope.

Key AED principles tested on the exam:

• Apply the AED as soon as it is available, minimizing CPR interruption.
• Ensure no one is touching the patient during analysis and shock ("clear").
• Resume compressions immediately after a shock or a "no shock advised" message — do not pause to check a pulse if compressions can continue per current guidelines.
• Remove medication patches, dry a wet chest, and avoid placing pads over an implanted device or directly over jewelry.

Team-Based Resuscitation and the AEMT Role

Real resuscitations are choreographed teamwork. The Clinical Judgment domain overlaps here: the exam rewards clear communication, closed-loop orders, defined roles, and minimal chaos. As an AEMT on a resuscitation team, your contributions extend beyond compressions.

AEMT-Scope Contributions During Arrest

• Airway and ventilation — maintain an open airway, use airway adjuncts, provide bag-valve-mask (BVM) ventilation, and place a supraglottic airway where trained and authorized. Avoid hyperventilation; deliver controlled ventilations.
• Vascular access — establish intravenous (IV) access, and intraosseous (IO) access where trained and protocol authorizes, so resuscitation medications and fluids can be given by the team.
• CPR and AED integration — maintain the compression-rhythm-shock cycle, coordinate clean handoffs, and call out timing.
• Documentation and communication — track interventions, times, and rhythm changes; communicate clearly with the team and medical direction.

Keep roles explicit: who compresses, who manages the airway, who runs the AED/monitor, and who documents and communicates. Closed-loop communication ("IV established" / "copy, IV established") prevents missed steps.

Return of Spontaneous Circulation (ROSC) Care

When a pulse returns, the patient is critically unstable and needs structured post-arrest care. The exam expects these priorities:

Hyperventilation after ROSC is a classic distractor — it reduces venous return and worsens outcomes. Be ready to restart CPR immediately if the patient re-arrests.

Termination and Non-Initiation Concepts

Whether to start or stop resuscitation is governed by protocol, valid legal documents, and medical direction — never personal preference. Concepts the exam may test:

• Valid Do Not Resuscitate (DNR) order or advance directive — resuscitation may be withheld when a valid, applicable document or POLST/MOLST is present and protocol allows.
• Obvious signs of death — situations such as injuries incompatible with life or dependent lividity/rigor may justify non-initiation per protocol.
• Field termination of resuscitation — some systems allow termination after a defined resuscitation effort, contact with medical direction, and meeting protocol criteria.

When in doubt and no valid directive is confirmed, begin resuscitation and contact medical direction. Document the rationale, the document reviewed, and any orders received.