CPR Basics: Adult, Child, and Infant Resuscitation

Introduction

Cardiopulmonary resuscitation (CPR) is an emergency lifesaving procedure performed when the heart stops beating. Immediate CPR can double or triple chances of survival after cardiac arrest. The American Heart Association (AHA) updates guidelines every 5 years, with the most recent update in 2020 emphasizing the C-A-B sequence (Compressions, Airway, Breathing) for all age groups.

The Chain of Survival

Link	Action	Description
1	Early Recognition and Activation	Recognize cardiac arrest, call 911
2	Early CPR	Immediate chest compressions to maintain blood flow
3	Rapid Defibrillation	Use AED as soon as available
4	Advanced Life Support	EMS arrival with medications and airway management
5	Post-Cardiac Arrest Care	Targeted temperature management, PCI, multidisciplinary care
6	Recovery	Rehabilitation, neurological assessment, support

Recognizing Cardiac Arrest

Sign	Description
Unresponsiveness	No response to tapping and shouting
No breathing or agonal breathing	Absent breathing or occasional gasping (agonal respirations)
No pulse	Absent carotid (adult/child) or brachial (infant) pulse
Cyanosis	Blue or gray discoloration of skin, especially lips and nail beds
Loss of consciousness	Sudden collapse

BLS Sequence: C-A-B (Compressions, Airway, Breathing)

Adult CPR (Puberty and older)

Step	Action	Details
1	Scene safety	Ensure environment is safe for rescuer and victim
2	Check responsiveness	Tap and shout “Are you OK?”
3	Activate EMS	Call 911 or send someone to call; get AED
4	Check pulse	Carotid artery, 5-10 seconds
5	Compressions	30 compressions at 2-inch (5 cm) depth, 100-120/min
6	Airway	Head-tilt chin-lift or jaw thrust (if suspected spinal injury)
7	Breathing	2 rescue breaths, each 1 second, see chest rise
8	Ratio	30:2 compressions to breaths
9	AED	Apply pads, follow prompts, resume CPR immediately after shock

Child CPR (1 year to puberty)

Step	Action	Details
Compression depth	Approximately 2 inches (5 cm)	Use one or two hands as needed
Compression rate	100-120 per minute	Same as adult
Compression-to-ventilation ratio	30:2 (single rescuer), 15:2 (two rescuers)	15:2 preferred with two rescuers
Pulse check	Carotid or femoral artery	5-10 seconds
Ventilation	1 second per breath	Visible chest rise
AED	Use pediatric pads if available	Standard pads acceptable if pediatric unavailable

Infant CPR (Under 1 year)

Step	Action	Details
Compression technique	Two-finger technique (single rescuer) or two-thumb encircling (two rescuers)	Place fingers on lower half of sternum
Compression depth	Approximately 1.5 inches (4 cm)	1/3 anterior-posterior chest depth
Compression rate	100-120 per minute	Same as adult
Compression-to-ventilation ratio	30:2 (single rescuer), 15:2 (two rescuers)	15:2 with two rescuers
Pulse check	Brachial artery	Inner upper arm
Ventilation	Gentle puffs, 1 second per breath	Do not overinflate
AED	Pediatric pads/attenuator	If unavailable, use adult pads (do not overlap)

Compression Technique Details

Proper Hand Placement

Aspect	Adult	Child	Infant
Hand position	Center of chest, lower half of sternum	Center of chest, lower half of sternum	Two fingers on lower half of sternum
Hand configuration	Heel of one hand, other hand on top	One or two hands	Two fingers (single rescuer)
Elbow position	Locked straight	Locked straight	Straight arm if using two-thumb

Compression Quality Metrics

Metric	Target	Consequences of Poor Technique
Rate	100-120/min	Too slow: inadequate perfusion; Too fast: inadequate filling
Depth (adult)	2.0-2.4 inches (5-6 cm)	Shallow: ineffective perfusion; Excessive: injury risk
Chest recoil	Complete after each compression	Incomplete: reduced cardiac output
Interruptions	Minimize, limit to <10 seconds	Reduces survival rates
Duty cycle	50:50 compression:relaxation	Affects blood flow

Rescue Breathing

Ventilation Techniques

Method	Indication	Technique
Mouth-to-mouth	No barrier device	Pinch nose, seal mouth, give 1-second breaths
Mouth-to-mask	Barrier device available	Use pocket mask with one-way valve
Bag-valve-mask (BVM)	Healthcare providers	Two-person technique preferred for seal
Advanced airway	Paramedics/physicians	Endotracheal tube, supraglottic airway

Rescue Breathing Without Compressions

Condition	Rate	Notes
Opioid overdose with pulse	1 breath every 5-6 seconds (10-12/min)	If no response, treat as cardiac arrest
Drowning with pulse	1 breath every 5-6 seconds	Begin with 2 rescue breaths
Respiratory arrest only	1 breath every 5-6 seconds	Recheck pulse every 2 minutes

AED (Automated External Defibrillator)

AED Operation

Step	Action
1	Turn on AED
2	Expose chest (remove clothing, dry if wet, shave excessive hair)
3	Apply pads: one on right upper chest, one on left lower side
4	Ensure no one touches victim during rhythm analysis
5	If shock advised: clear victim, press shock button
6	Immediately resume CPR starting with compressions
7	Continue for 2 minutes, then re-analyze

Special AED Situations

Situation	Modification
Child 1-8 years	Use pediatric pads/attenuator; if unavailable, use adult pads (anterior-posterior placement)
Infant	Pediatric pads preferred; if unavailable, adult pads (anterior-posterior)
Implantable cardioverter-defibrillator (ICD)	Place pad at least 1 inch away from device
Pacemaker	Same as ICD, place pads away from generator
Medication patch (nitro, fentanyl, etc.)	Remove patch, wipe skin clean
Wet victim	Dry chest thoroughly before pad placement
Excessive chest hair	Shave area where pads will be placed
Jewelry/piercings	Do not delay; place pads around jewelry

Recovery Position

Steps for Recovery Position (Unconscious, Breathing Normally)

Step	Instruction
1	Kneel beside the person
2	Place nearest arm at right angle to body, palm up
3	Bring far arm across chest, hand against cheek
4	Grasp far leg above knee, pull toward you
5	Roll person toward you, keeping hand against cheek
6	Adjust top leg so hip and knee are at 90 degrees
7	Tilt head back to maintain airway

Contraindications

Condition	Alternative Position
Suspected spinal injury	Log roll as a unit, maintain spine alignment
Pregnancy (3rd trimester)	Left lateral recumbent position
Severe trauma	Minimize movement, treat life threats in place

Foreign Body Airway Obstruction (FBAO)

Victim	Conscious Technique	Unconscious Technique
Adult	Abdominal thrusts (Heimlich)	Lower to ground, begin CPR, check mouth before breaths
Child >1 year	Abdominal thrusts	Same as adult
Infant <1 year	5 back blows, 5 chest thrusts	Lower to ground, begin CPR, check mouth before breaths

When to Stop CPR

Reason	Rationale
Victim shows signs of life	Spontaneous breathing, movement, pulse returns
AED arrives and prompts analysis	Follow AED instructions
EMS arrives and takes over	Trained personnel assume care
Rescuer is too exhausted to continue	Safety of rescuer is important
Scene becomes unsafe	Environmental hazards
Valid DNR order presented	Legal advance directive
Obvious signs of irreversible death	Rigor mortis, dependent lividity, decapitation

Compression-Only CPR (Hands-Only CPR)

Aspect	Details
Indications	Untrained bystanders, unwilling/unable to give breaths
Contraindications	Drowning, drug overdose, children, infants (all require breaths)
Technique	Continuous compressions at 100-120/min, 2-inch depth
Rationale	Maintains coronary perfusion pressure; breaths omitted until EMS arrives
Outcomes	Similar or better than standard CPR in out-of-hospital adult cardiac arrest

Agonal Breathing

Feature	Description
Definition	Irregular, gasping, noisy breathing after cardiac arrest
Mechanism	Brainstem reflex due to hypoxia
Appearance	Occasional, labored, slow rate (<10/min)
Mistaken for	Normal breathing (causing delayed CPR)
Key teaching	“If you’re not sure if breathing is normal, act as if it’s not”

Summary of Key Differences by Age

Parameter	Adult	Child (1yr-puberty)	Infant (<1yr)
Compression depth	2-2.4 inches (5-6 cm)	2 inches (5 cm)	1.5 inches (4 cm)
Compression method	Two hands	One or two hands	Two fingers or two-thumb
Compression:ventilation ratio	30:2	30:2 (single), 15:2 (two)	30:2 (single), 15:2 (two)
Pulse check site	Carotid	Carotid or femoral	Brachial
AED pads	Adult	Pediatric (1-8) or adult	Pediatric or adult A-P
Rescue breath volume	Full breath	Moderate breath	Gentle puff
Hands-only CPR	Appropriate	Not recommended	Not recommended
Compression rate	100-120/min	100-120/min	100-120/min