Cardiac Arrest: Recognition, Immediate Action & Chain of Survival
Cardiac arrest is the abrupt loss of heart function, breathing, and consciousness. It is not a heart attack (myocardial infarction = blocked blood flow to heart muscle). Cardiac arrest is an electrical malfunction causing the heart to stop pumping effectively. Immediate action saves lives.
Recognize Cardiac Arrest — The "No-No-No" Signs
- No Response: Tap shoulders, shout "Are you OK?" — no movement, no verbal response.
- No Normal Breathing: Not breathing or only gasping (agonal respirations — snorting, gurgling, irregular). Gasping is not breathing.
- No Pulse (Lay Rescuer): Do not waste time checking pulse. Assume arrest if unresponsive + not breathing normally.
Immediate Action: The Chain of Survival
- Call 911 / Activate Emergency Response (or send someone). Put phone on speaker.
- Start High-Quality CPR Immediately:
- Push Hard & Fast: Center of chest (lower half of sternum), 2–2.4 in (5–6 cm) deep, 100–120/min. Allow full recoil.
- Minimize Interruptions: <10 seconds for breaths/analysis.
- Hands-Only CPR (untrained/unwilling): Continuous compressions until AED/EMS arrives.
- Trained: 30 compressions : 2 breaths (barrier device if available).
- Use AED As Soon As Available:
- Turn on → follow voice prompts.
- Apply pads (adult/pediatric) to bare chest.
- Stand clear for analysis/shock.
- Resume CPR immediately after shock (or "no shock advised").
- Advanced Life Support (EMS/Hospital): Airway, IV/IO meds, post-cardiac arrest care (targeted temperature management, coronary angiography, ICU).
- Recovery & Rehabilitation: Physical, cognitive, emotional support for survivor & family.
Potential Warning Symptoms (Hours/Days Before)
Some victims experience prodromal symptoms (more common in women):
- Chest pain/discomfort (pressure, squeezing, fullness)
- Shortness of breath
- Unexplained fatigue, weakness
- Palpitations, lightheadedness, syncope
- Nausea, indigestion, cold sweat
These warrant urgent medical evaluation — they may precede sudden cardiac arrest.
Special Considerations
- Children/Infants: Asphyxial arrest more common. 2-finger (infant) / 1-2 hand (child) compressions. 15:2 ratio (2 rescuers).
- Drowning: 5 initial rescue breaths, then CPR.
- Opioid Overdose: Naloxone + CPR.
- Pregnancy: Manual left uterine displacement during CPR; perimortem C-section if >20 wks & no ROSC in 4 min.
Key Metrics for Quality CPR
| Metric | Target |
|---|---|
| Compression Rate | 100–120/min |
| Compression Depth (Adult) | 2–2.4 in (5–6 cm) |
| Chest Compression Fraction | >80% |
| Pre/Post-Shock Pause | <10 sec / <5 sec |
| Ventilation Rate (with advanced airway) | 10 breaths/min (1 every 6 sec) |