# Cardiac Arrest: Pediatric and Adult Resuscitation

## Introduction

Cardiac arrest management is a core competency for all physicians. While the fundamental principle of **high-quality CPR** is universal, the etiologies, algorithms, and post-resuscitation care differ substantially between children and adults. Pediatric cardiac arrest is most commonly due to **respiratory failure or shock** progressing to asystole, whereas adult cardiac arrest is predominantly **cardiac in origin** with ventricular fibrillation or pulseless ventricular tachycardia. Med-peds physicians must be proficient in both PALS and ACLS frameworks.

## Epidemiology and Etiology

### Pediatric Cardiac Arrest

In-hospital cardiac arrest (IHCA) incidence: 1-6 per 1,000 pediatric admissions. Out-of-hospital cardiac arrest (OHCA) survival to discharge: approximately 10-12%. Most common initial rhythms: **asystole and PEA** (non-shockable) in >80% of cases. Primary causes: respiratory failure (airway obstruction, pneumonia, drowning), septic shock, trauma, SIDS. **Shockable rhythms** (VF/pVT) are more common in adolescents and those with underlying cardiac disease.

### Adult Cardiac Arrest

OHCA incidence: ~350,000 annually in the United States. Survival to discharge for witnessed VF arrest with bystander CPR: 25-40%. Most common initial rhythms: VF/pVT in ~25% of OHCA cases (higher in witnessed arrests) Primary causes: coronary artery disease, cardiomyopathy, primary arrhythmias, pulmonary embolism. **Hs and Ts** mnemonic helps identify reversible causes.

## BLS Fundamentals: Pediatric vs. Adult

| Parameter | Infants | Children (1-puberty) | Adults |
|-----------|---------|---------------------|--------|
| Compression:ventilation (2 rescuers) | 15:2 | 15:2 | 30:2 |
| Compression:ventilation (1 rescuer) | 30:2 | 30:2 | 30:2 |
| Compression depth | 4 cm (1.5 in) | 5 cm (2 in) | 5-6 cm (2-2.4 in) |
| Compression rate | 100-120/min | 100-120/min | 100-120/min |
| Defibrillation (1st shock) | 2 J/kg | 2 J/kg | 120-200 J biphasic |
| Defibrillation (subsequent) | 4 J/kg | 4 J/kg | Escalating energy |
| Epinephrine dose | 0.01 mg/kg (max 1 mg) | 0.01 mg/kg (max 1 mg) | 1 mg IV q3-5 min |

**Compression-to-ventilation ratio**: 30:2 for single rescuer (all ages); 15:2 for two-rescuer pediatric CPR. **Compression depth**: At least one-third AP chest diameter in infants and children (4 cm infants, 5 cm children); at least 5 cm (2 inches) in adults, no more than 6 cm. **Compression rate**: 100-120/minute for all ages. **Ventilation emphasis**: Critical in pediatric arrest given respiratory etiology; compression-only CPR may be appropriate for witnessed adult arrest with presumed cardiac cause. **AED use**: Standard adult pads/dose for age >=8 years; pediatric dose-attenuator pads for ages 1-8; manual defibrillator preferred for infants.

![BLS algorithm comparison between pediatric and adult resuscitation](illustration-bls-pediatric-vs-adult.jpg)

## ACLS and PALS Algorithms

### Shockable Rhythms (VF/pVT)

**Defibrillation**: First shock 2 J/kg (pediatric), 120-200 J biphasic (adult); subsequent shocks 4 J/kg (pediatric), escalating energy (adult) Resume CPR immediately after shock for 2 minutes before rhythm check. **Epinephrine**: 0.01 mg/kg IV/IO (pediatric, max 1 mg) or 1 mg IV (adult) every 3-5 minutes. **Amiodarone**: 5 mg/kg IV/IO (pediatric, max 300 mg) or 300 mg IV bolus (adult) for refractory VF/pVT. **Lidocaine**: Alternative antiarrhythmic; 1 mg/kg IV in both populations.

### Non-Shockable Rhythms (Asystole/PEA)

High-quality CPR with epinephrine every 3-5 minutes. Identify and treat reversible causes (Hs and Ts) **Hs**: Hypovolemia, Hypoxia, Hydrogen ion (acidosis), Hypo/hyperkalemia, Hypothermia, Hypoglycemia (especially pediatric) **Ts**: Tension pneumothorax, Tamponade, Toxins, Thrombosis (pulmonary/coronary)

### Special Pediatric Considerations

**Neonatal resuscitation**: Follows NRP algorithm; initial steps include warmth, drying, stimulation, airway clearance. Neonatal epinephrine dose: 0.01-0.03 mg/kg IV; 0.05-0.1 mg/kg via endotracheal route. **Umbilical venous catheter** is the preferred emergency vascular access in neonates. **Intraosseous (IO) access**: First-line alternative to IV access in pediatric resuscitation when IV cannot be established rapidly.

## Post-Cardiac Arrest Care

### Targeted Temperature Management (TTM)

**Adults**: TTM at 32-36 degrees C for at least 24 hours for comatose survivors of cardiac arrest (per TTM2, targeting normothermia and fever prevention is an acceptable alternative) **Pediatrics**: TTM at 32-34 degrees C for comatose children post-IHCA; considered for OHCA though evidence is less robust. **Neonates**: Therapeutic hypothermia (33.5 degrees C for 72 hours) is standard for moderate-severe hypoxic-ischemic encephalopathy.

### Hemodynamic Optimization

Target MAP to ensure adequate cerebral perfusion; avoid hypotension. Coronary angiography for adults with suspected cardiac etiology (STEMI or high suspicion for ACS) Echocardiography to assess myocardial function and guide inotropic support. Avoid hyperoxia; target SpO2 94-98% and PaO2 in normal range.

### Neurologic Prognostication

Defer prognostication for at least **72 hours** after return to normothermia. Use multimodal assessment: clinical examination (pupillary reflexes, motor response), EEG, somatosensory evoked potentials, neuroimaging, and serum biomarkers (NSE) No single test should be used in isolation to predict poor outcome. In children, recovery potential may be greater; cautious and extended observation is warranted.

![Post-cardiac arrest care bundle for pediatric and adult patients](illustration-post-cardiac-arrest-care.jpg)

## Quality of CPR and Team Dynamics

**Minimize interruptions** in chest compressions; aim for chest compression fraction >80%. Rotate compressors every 2 minutes to prevent fatigue-related decline in quality. Use real-time CPR feedback devices when available. Structured debriefing after resuscitation events improves team performance. **Family presence** during resuscitation is recommended when feasible with a designated support person.

![High-quality CPR metrics and feedback systems](illustration-cpr-quality-metrics.jpg)

## Clinical Pearls

Pediatric cardiac arrest is primarily respiratory in etiology, making early airway management and ventilation essential; adult arrest is primarily cardiac, making early defibrillation the priority. High-quality CPR with minimal interruptions is the single most important determinant of survival in all age groups. The two-rescuer compression-to-ventilation ratio in children is 15:2, reflecting the importance of ventilation in pediatric resuscitation. Post-arrest targeted temperature management and avoidance of hyperthermia improve neurologic outcomes. Neurologic prognostication should be deferred at least 72 hours and use multimodal assessment to avoid premature withdrawal of care.

## References

1. Topjian AA, Raymond TT, Atkins D, et al. Part 4: Pediatric basic and advanced life support: 2020 AHA guidelines. *Circulation*. 2020;142(16 Suppl 2):S469-S523.
2. Panchal AR, Bartos JA, Cabanas JG, et al. Part 3: Adult basic and advanced life support: 2020 AHA guidelines. *Circulation*. 2020;142(16 Suppl 2):S366-S468.
3. Dankiewicz J, Cronberg T, Lilja G, et al. Hypothermia versus normothermia after out-of-hospital cardiac arrest (TTM2). *N Engl J Med*. 2021;384(24):2283-2294.
4. Wyckoff MH, Wyllie J, Aziz K, et al. Neonatal life support: 2020 International Consensus on Cardiopulmonary Resuscitation. *Circulation*. 2020;142(16 Suppl 1):S185-S221.