CPR: cardiopulmonary resuscitation

Cardiopulmonary resuscitation (CPR) is the single most life-saving skill available to any bystander. When a person's heart stops, every minute without compressions reduces survival by 7–10% per the American Heart Association (AHA) 2025 Emergency Cardiovascular Care (ECC) guidelines. Any CPR — even imperfect CPR — is dramatically better than no CPR. This page teaches complete step-by-step procedures for adults, children, and infants, including what to do when an Automated External Defibrillator (AED) arrives, how to use hands-only CPR when mouth-to-mouth is not possible, and how to make ethically sound decisions about terminating resuscitation when Advanced Life Support (ALS) will not arrive.

Action block

Do this first: Check responsiveness — tap the victim's shoulders firmly and shout "Are you okay?" Time required: Active: continuous until ALS arrives, ROSC, or 30 min without signs of life in austere conditions; rescuer rotation every 2 minutes (5 cycles) Cost range: CPR training is inexpensive to free (Stop The Bleed / Red Cross); a CPR pocket mask is inexpensive; an AED is a moderate to significant investment for home use Skill level: Beginner (basic compressions + AED); intermediate (rescue breaths + full 30:2 cycle); expert for integration with MARCH (Massive hemorrhage, Airway, Respiration, Circulation, Hypothermia) / ABCDE (Airway, Breathing, Circulation, Disability, Exposure) assessment. All levels save lives — begin at your current level. Tools and supplies: Nitrile gloves (barrier protection); CPR pocket mask or face shield (rescue breaths); AED if available; firm flat surface (floor preferred over mattress) Safety warnings: See Stop immediately for these conditions below — DNR orders, scene safety, signs of biological death

Quick reference

Field	What to know
Outcome target	Restore circulation and breathing (ROSC — Return Of Spontaneous Circulation); maintain brain perfusion until ALS arrives
First-line action	30 chest compressions at 100–120/min to at least 2 in (5 cm) depth (adult), then 2 rescue breaths — OR continuous compressions if untrained
Escalate if	AED arrives (apply immediately); trained EMS (Emergency Medical Services) arrives (transfer care); patient shows ROSC (stop CPR, place in recovery position)
Stop if	Scene becomes unsafe; patient has visible DNR order; signs of irreversible biological death (rigor mortis, dependent lividity, decapitation, injuries incompatible with life)

Educational use only

This page provides general educational information for emergency preparedness scenarios. CPR technique degrades without hands-on practice. Take a certified CPR course through the AHA, American Red Cross, or National Safety Council — and recertify every two years. This content does not replace professional medical training. Call Emergency Medical Services (911 in the US) whenever possible. These procedures are for situations where professional care is delayed or unavailable.

When to use this

Use this when:

The person is unresponsive — does not react to a firm tap on the shoulders and a loud shout
Breathing is absent or abnormal — no chest rise, no breath sounds, or only gasping (agonal respirations)
You observe cardiac arrest — confirmed by unresponsiveness plus absent normal breathing (lay rescuers do not need to check for a carotid pulse; AHA 2025 guidelines note that lay rescuers cannot reliably detect a pulse and should begin CPR without a pulse check. Medical responders may check for ≤10 seconds.)

Do not use this when:

The patient is responsive, talking, or breathing normally
A valid Do Not Resuscitate (DNR) order is visible or presented by family or healthcare proxy
Injuries are incompatible with life (decapitation, complete transection of the torso)
Signs of irreversible biological death are present: rigor mortis (stiff muscles), dependent lividity (fixed purple-red skin pooling on the underside of the body), or decomposition
The scene is unsafe and you cannot make it safe — an unprotected rescuer becomes a second victim

Stop and escalate if:

The patient regains a pulse and resumes normal breathing (ROSC) — place in recovery position and monitor
An AED arrives — apply pads and follow voice prompts immediately without interrupting compressions for more than 10 seconds
Trained EMS assumes care — brief them on elapsed time, cycles performed, and any medications or defibrillation given
You are physically unable to continue and no second rescuer is available
The scene becomes unsafe

Choosing a method

All methods use the same rate: 100–120 compressions per minute.

Method	When to use	Compression technique (depth + hand position)	Ratio and AED
Adult CPR	Victim has signs of puberty or is ≥8 years and puberty-sized	Both hands, lower half of sternum; ≥2 in (5 cm), max 2.4 in (6 cm)	30:2 solo or dual rescuer; adult pads upper right chest + lower left side
Child CPR	1 year through onset of puberty	One or two hands (size-appropriate), lower half of sternum; ~2 in (5 cm) / ≥1/3 anterior-posterior (AP) chest depth	30:2 solo; 15:2 two rescuers; pediatric pads preferred — adult pads if unavailable, no overlap
Infant CPR	Under 1 year (excluding newborns)	One-hand lone-rescuer technique or 2-thumb encircling-hands (two rescuers, preferred), lower half of sternum; ~1.5 in (4 cm) / ≥1/3 AP depth	30:2 solo; 15:2 two rescuers; pediatric pads with attenuator; adult pads as last resort
Hands-only CPR	Untrained lay rescuers, all adult arrests, unwillingness to provide rescue breaths	Same as adult — both hands, lower half of sternum; ≥2 in (5 cm)	Continuous compressions, no breaths; apply AED as soon as available

Adult CPR (age ≥ puberty)

This procedure follows the AHA 2025 ECC Guidelines for Adult Basic Life Support (BLS).

Before you start - Gloves: Put on nitrile gloves before contact. If unavailable, use any barrier or proceed without — imperfect barrier is better than no CPR. - Surface: A firm, flat surface is required. Soft surfaces (mattresses, deep carpet, grass) absorb compression force and reduce effective depth. Move the victim to the floor if possible. - Scene: Confirm no ongoing hazards. If indoors, confirm adequate space to kneel at the victim's side.

Confirm scene safety. Look for traffic, downed power lines, fire, active violence, toxic fumes. Do not approach an unsafe scene until hazards are controlled.
Check responsiveness. Kneel at the victim's side. Tap the shoulders firmly with both hands and shout loudly: "Are you okay? Are you okay?" A verbal response or purposeful movement means CPR is not needed — assess them further.
Call for help and send for an AED. If you are alone, call 911 first (in witnessed adult cardiac arrest, most causes are cardiac — an AED matters immediately). If others are present, shout specific assignments: "You — call 911 now. You — get the AED from [location]." Put the phone on speaker and begin CPR.
Check breathing — no more than 10 seconds. Look at the chest for rise and fall. Listen for breath sounds. Feel for air against your cheek. Agonal breathing — occasional gasping, labored or gurgling — counts as NOT breathing. If you observe it, begin CPR immediately.
Position your hands. Place the heel of your dominant hand on the center of the chest — the lower half of the sternum, between the nipple line. Place your other hand on top, fingers interlaced. Straighten your arms and lock your elbows. Position your shoulders directly over your hands so body weight drives compressions.
Deliver 30 compressions. Press down at least 2 inches (5 cm) but no more than 2.4 inches (6 cm). Allow the chest to fully spring back (recoil) to its natural position after each compression — do not lean on the chest between compressions. Maintain a rate of 100–120 compressions per minute. If counting helps: "one-and-two-and-three-and..." One complete set of 30 compressions should take 15–18 seconds. The Bee Gees' "Stayin' Alive" is approximately 103 beats per minute (BPM) — use its rhythm to anchor your rate.
Open the airway. Place one hand on the victim's forehead. Place two fingers of your other hand under the bony prominence of the chin — not the soft tissue. Tilt the head back and lift the chin until the face is parallel to the ceiling. (If spinal injury is suspected from the mechanism, use a jaw-thrust maneuver instead: place both hands alongside the jaw, push the jaw forward without moving the neck.)
Deliver 2 rescue breaths. Pinch the nose closed with your thumb and index finger. Seal your mouth over the victim's mouth (use a CPR pocket mask if available). Deliver each breath over 1 second — just enough to see the chest rise. Pause 1 second between breaths to allow passive exhalation. Two complete breaths should take 4–5 seconds. If the first breath does not produce chest rise, reposition the head and try again before the second breath.
Return immediately to compressions. The pause for rescue breaths must be under 10 seconds. Resume 30 compressions. This 30:2 cycle repeats continuously.
Switch rescuers every 2 minutes (5 cycles). Compression quality degrades measurably after 90 seconds. If a second rescuer is available, alternate on a verbal count: "Switch on three — one, two, three." The switch itself should take no more than 5 seconds.
Apply the AED as soon as it arrives. Do not delay AED use to complete another compression cycle. Power it on, apply pads as shown in the diagrams (upper right chest + lower left side below the armpit), stand clear during rhythm analysis, and deliver a shock if prompted. Resume compressions immediately after the shock — do not pause to check for a pulse first.
Continue until EMS assumes care, the victim shows ROSC (moves, breathes normally, opens eyes), the AED prompts you that resuscitation is no longer indicated, or you reach austere-environment decision thresholds (see Austere and prolonged CPR).

Field note

Any CPR is better than no CPR. The most common reason bystanders do nothing is fear of doing it wrong. Imperfect compressions — shallower than ideal, slightly off-rate — still move oxygenated blood to the brain. A brain without perfusion suffers irreversible damage within 4–6 minutes. Imperfect action beats perfect hesitation every time.

Child CPR (1 year through puberty)

Child CPR follows the same fundamental sequence as adult CPR. The critical differences are compression depth, hand position, call-first vs. CPR-first decision, and two-rescuer ratio.

Before you start - Use the adult procedure above as your framework. Apply the child-specific modifications listed in steps below. - If you are alone and the arrest was unwitnessed (you did not see the child collapse), give 2 minutes of CPR before calling 911. Pediatric arrest is most often caused by respiratory failure — rescue breaths matter early, and 2 minutes of CPR before pausing to call delivers that oxygen. - If you witnessed the collapse, call 911 first (witnessed pediatric arrest more likely represents a primary cardiac event requiring AED).

Child-specific modifications:

Check responsiveness. Same as adult — tap shoulders firmly and shout.
Compression depth. Compress at least one-third the anterior-posterior (AP) depth of the chest — approximately 2 inches (5 cm) in most children. "At least one-third" matters because children vary widely in size. A small 4-year-old and a large 11-year-old are both "children" by age, but the depth of the chest differs. Target one-third depth on every compression.
Hand position. Use one hand or two hands, depending on the child's size — whichever technique delivers adequate depth. For a small child (under approximately 6 years), one hand placed on the lower half of the sternum may be sufficient. For a larger child approaching adult size, use the two-hand adult technique.
Rate and ratio. Rate is identical to adults: 100–120 compressions per minute. Single-rescuer ratio: 30:2. Two-rescuer ratio: 15:2 (pediatric two-rescuer ratio differs from adult — more frequent rescue breaths reflect the respiratory origin of most pediatric arrests).
AED pads. Use pediatric-sized pads or a pediatric attenuator key if available — these reduce the energy delivered to the smaller heart. If only adult pads are available and they can be placed without overlapping, use them. One pad on the center of the chest and one on the back (anterior-posterior placement) is an alternative for small children to prevent pad contact.
Do not skip rescue breaths in children. Hands-only CPR is appropriate for lay rescuers in witnessed adult cardiac arrest because most adult arrests have a cardiac cause. In children, the primary mechanism is usually respiratory — oxygen deprivation leads to cardiac arrest. Rescue breaths replenish depleted oxygen more effectively in children than in adults.

Field note

Pediatric arrest is almost always respiratory in origin — children's hearts are rarely the primary failure point. A child drowns, chokes, suffocates, or has a severe asthma attack, and cardiac arrest follows seconds to minutes later. Rescue breaths matter more in children than in adults. Do not omit them because you are uncomfortable, even if you skip them in adults.

Infant CPR (under 1 year)

Infants require a different hand technique and compression depth. The principles remain identical — depth, rate, recoil, and ratio — but the anatomy is different enough that adult technique applied to an infant causes harm.

Before you start - Infant CPR applies to babies from birth (excluding newborns in the first minutes after delivery, who follow neonatal resuscitation protocols) to one year of age. - Never shake an infant to check responsiveness — shaking causes traumatic brain injury. - Infant rescue breaths cover BOTH the mouth and nose simultaneously, not mouth-to-mouth alone, because the infant face is too small to seal separately.

Check responsiveness. Tap the sole of the foot firmly. Shout the infant's name or "Hello!" Do not tap the shoulders or shake the head.
Call for help. Follow the same witnessed vs. unwitnessed rule as child CPR. Alone + unwitnessed: give 2 minutes of CPR first. Witnessed: call 911 first (or send a bystander), then immediately begin CPR.
Check breathing ≤10 seconds. Watch chest for rise, listen for breath sounds, feel for air. Agonal gasping = not breathing.
Position the infant. Place the infant supine on a firm, flat surface — a table or the floor. If outdoors or on a soft surface, carry the infant on your forearm while providing compressions (one-arm carry technique for very small infants). Ensure the head is in a neutral position, not hyperextended or flexed — both obstruct the airway.
Choose your compression technique:
One-hand technique (lone rescuer): Place the heel of one hand on the lower half of the sternum, just below the nipple line. The 2025 AHA guidelines moved away from the prior two-finger method because systematic reviews showed two fingers consistently fail to achieve the required one-third AP chest depth. The one-hand technique delivers more reliable depth for a single rescuer.
Two-thumb encircling-hands technique (two rescuers — preferred): Place both thumbs side by side on the lower half of the sternum. Wrap both hands around the infant's torso so your fingers support the back. This technique delivers superior compression depth and rate with less rescuer fatigue. Research consistently shows higher compression quality with this technique; it is the preferred method when two rescuers are available.
Compress approximately 1.5 inches (4 cm) — at least one-third of the infant's AP chest depth. The infant chest is small. You will need less force than you expect, but the target depth is non-negotiable. Inadequate compression depth means inadequate perfusion.
Rate: 100–120 compressions per minute. Identical to adult and child.
Ratio: 30:2 for one rescuer; 15:2 for two rescuers. The 15:2 two-rescuer pediatric ratio applies to both infants and children.
Rescue breaths for infants — cover both mouth and nose. Seal your mouth over the infant's mouth and nose simultaneously (the infant face is small enough to cover both). Deliver a gentle puff — a baby's tidal volume is approximately 7 mL per kg (0.11 fl oz per lb) body weight, far less than an adult. Over-ventilation distends the stomach and risks barotrauma. Use only enough volume to see the chest rise visibly. One second per breath.
AED. Use an AED with a pediatric attenuator (dose-reduction key) when available. Anterior-posterior pad placement (one on the chest, one on the back) is recommended for infants. If only adult pads without an attenuator are available and the pads can be placed without touching each other, use them — some defibrillation is better than none.
Continue the 30:2 (solo) or 15:2 (two-rescuer) cycle until EMS arrives, ROSC occurs, or austere-condition termination criteria are met.

Hands-only CPR (lay rescuers, all ages)

Hands-only CPR — continuous chest compressions at 100–120 per minute without rescue breaths — is the AHA-endorsed option for untrained lay rescuers and for trained rescuers unwilling to provide mouth-to-mouth contact.

The AHA updated lay-rescuer guidance specifically to overcome the documented hesitation around mouth-to-mouth contact. The conclusion: continuous chest compressions with no rescue breaths substantially outperform no intervention at all.

When hands-only CPR is appropriate:

Untrained lay rescuer in any adult cardiac arrest
Trained rescuer who is unable or unwilling to provide rescue breaths due to barrier concerns
Any witnessed sudden collapse in an adult in a public setting

When hands-only CPR is NOT preferred (rescue breaths matter more):

Drowning victims — hypoxia (oxygen deprivation) is the primary problem; rescue breaths are critical
Opioid overdose — respiratory depression causes the cardiac arrest; ventilation is the definitive treatment
Pediatric arrest (children and infants) — respiratory origin; rescue breaths matter significantly
Unwitnessed adult arrest where time since collapse is unknown and hypoxia may be established

Hands-only technique:

Call 911 immediately.
Place the heel of one hand on the center of the chest (lower half of the sternum).
Place the other hand on top.
Push hard and fast — at least 2 inches (5 cm) deep for adults — at 100–120 compressions per minute.
Do not stop for breaths. Do not stop to check for a pulse. Continue until EMS arrives or takes over.

Field note

The AHA changed lay-rescuer guidance to hands-only specifically because witnessed-arrest bystander CPR rates were poor. They concluded that confident, imperfect compressions delivered without hesitation produce better outcomes than perfect 30:2 cycles delivered 30 seconds late because the rescuer was uncertain. Confidence is itself a clinical variable. If you can only do compressions, do them — now, hard, and fast.

Austere and prolonged CPR decisions

When ALS cannot reach the patient — remote wilderness, active disaster, collapsed infrastructure — standard CPR guidance assumes an ALS endpoint that does not exist. These situations require different decision-making.

Continue high-quality CPR as long as you can maintain quality. Switching rescuers every 2 minutes is not optional when multiple rescuers are available — compression quality degrades after 90 seconds, and degraded compressions are dramatically less effective than switching.

Factors that support continued CPR beyond 20 minutes:

Hypothermia ("not dead until warm and dead"): The Wilderness Medical Society (WMS) and International Liaison Committee on Resuscitation (ILCOR) recognize that cold-water drowning victims and severely hypothermic patients have survived neurologically intact after more than 60 minutes of CPR. Do not terminate CPR on a hypothermic patient until core temperature reaches approximately 95°F (35°C). Rewarming must accompany CPR.
Pediatric patients: Children tolerate prolonged ischemia better than adults. Continue CPR in children longer than you would in adults.
Drowning: Especially cold-water drowning. Same principle as hypothermia — continue well past 20 minutes if the patient is cold.
Lightning strike: Lightning-strike cardiac arrest survivors have been documented after prolonged CPR. This is one of the highest-priority resuscitation scenarios in austere conditions. Prioritize these patients.

Factors that support termination of CPR after 30 minutes (austere/wilderness context, per WMS guidance):

The cardiac arrest was not witnessed — time to CPR is unknown, and significant anoxic brain injury may have occurred before compressions began
No shockable rhythm identified (if AED available)
Patient is non-hypothermic (core temperature at or near normal)
Not a drowning, lightning strike, or drug overdose
After 30 minutes of high-quality CPR, no signs of life have returned (no spontaneous movement, no pupil response, no respiratory effort)
Transport to definitive care is hours or days away

Termination of CPR after 30 minutes of high-quality effort in a non-hypothermic adult without a shockable rhythm is ethically appropriate in an austere setting where ALS is unavailable.

After stopping CPR: Document the time resuscitation was initiated, the duration, the interventions performed, and the criteria used to make the termination decision. This matters for incident reporting and for any subsequent family notification.

For Return Of Spontaneous Circulation (ROSC) — what to do after the heart restarts — see shock management, which covers the post-ROSC care priorities including positioning, temperature management, and monitoring for re-arrest.

Tools and substitutes

Ideal tool	Specs	Field-expedient substitute	Notes / limits
AED (Automated External Defibrillator)	Any listed model; pediatric attenuator for children	No substitute for defibrillation	AED + CPR triples survival vs. CPR alone in shockable-rhythm arrest; locate AEDs in public buildings in advance
CPR pocket mask	One-way valve; universal fit; inexpensive	Plastic wrap with a hole cut in center, OR a shirt draped over the face	Improvised barriers are far less protective; hands-only CPR is a better choice than a compromised improvised barrier
Nitrile gloves	Non-latex, disposable	Any gloves; plastic bags over the hands	Protects rescuer from bloodborne pathogen exposure; proceed without gloves if not available
Firm flat surface	Floor, hard ground	Backboard, door, table, or any hard rigid object slid under the torso	Soft surfaces (mattresses, grass, sand) absorb compression force and reduce effective depth by 30–50%
Watch or phone timer	Seconds display	Verbal counting in cadence (one-and-two-and...)	Cadence counting drifts under stress; use "Stayin' Alive" rhythm as a backup anchor
Bag-valve mask (BVM)	Adult and pediatric sizes; PEEP (positive end-expiratory pressure) valve	CPR pocket mask	BVM requires training to seal effectively; unskilled use delivers worse tidal volumes than a pocket mask

Failure modes

1. Inadequate compression depth

Operator cause: Fear of hurting the victim; using arm strength rather than body weight; kneeling too far to the side
Outcome: Insufficient ventricular filling and output; brain perfusion below the survival threshold
Recognition: Chest barely deflects; less than the width of two stacked adult fingers; feedback from a second observer
Recovery: Shift body weight directly over hands, straighten arms fully, lean into compressions. Rib fractures in CPR are common and survivable. Inadequate perfusion is not. Switch rescuers — depth degrades faster than any other quality metric under fatigue.

2. Incomplete chest recoil between compressions

Operator cause: Leaving body weight on the chest between compressions ("leaning"); exhaustion
Outcome: Impaired venous return to the right heart; reduced cardiac output on subsequent compressions
Recognition: Chest does not spring back fully to neutral between compressions; sternum visibly compressed throughout the cycle
Recovery: After each downstroke, fully lift body weight. Maintain hand contact for accurate placement but bear no weight during the recoil phase. This is the failure mode most closely tied to rescuer fatigue — switch every 2 minutes.

3. Compression rate outside 100–120 per minute

Operator cause: Anxiety-driven too-fast rate (>120/min); fatigue-driven too-slow rate (<100/min)
Outcome: Too fast — compressions become shallow and ventricles underfill; too slow — fewer perfusion cycles per minute and reduced coronary artery filling
Recognition: If 30 compressions complete in less than 15 seconds, rate is above 120. If 30 compressions take more than 18 seconds, rate is below 100.
Recovery: Anchor to the "Stayin' Alive" rhythm (~103 BPM). Count compressions aloud in sets of five: "one-two-three-four-five, one-two-three-four-ten..." Verbal counting slows rate drift under exhaustion.

4. Compression pauses exceeding 10 seconds

Operator cause: Extended pulse checks; lengthy transitions between compressions and rescue breaths; waiting to confirm AED shock delivered before resuming
Outcome: Coronary perfusion pressure drops to near zero within seconds of stopping compressions; each interruption requires multiple cycles to rebuild
Recognition: AED arrives and pads are applied while compressions are stopped; transition from breaths to compressions takes more than 10 seconds
Recovery: Resume compressions within 10 seconds of any pause. After AED shock: begin compressions immediately — do not wait to check for a pulse. The AED will analyze again at the next interval.

5. Failure to apply AED promptly

Operator cause: Unfamiliarity with device; continuing compressions when pads should be applied; deferring to a second rescuer who also hesitates
Outcome: Every minute without defibrillation in a shockable-rhythm arrest reduces survival by 7–10%
Recovery: AED is applied during CPR — one rescuer continues compressions while the other applies pads. Stop compressions only when the AED begins rhythm analysis. Know where AEDs are in your home, workplace, and frequented public spaces before you need them.
Prevention: Treat AED familiarization as a non-negotiable part of CPR training. Most AEDs provide audible, step-by-step voice prompts — they are designed for use by people who have never seen the device.

6. Rescuer fatigue degrading compression quality

Operator cause: Continuing past 90–120 seconds without a switch; no pre-planned rotation
Outcome: Gradual decline in rate, depth, and recoil quality — all three degrade simultaneously; the rescuer is often unaware
Recognition: Second observer notices shallowing depth; rescuer's verbal count slows; rate drops below 100
Recovery: If a second rescuer is available, switch every 2 minutes regardless of perceived fatigue. If alone, pace yourself — deep, deliberate compressions maintain more quality for longer than shallow fast ones. A brief 10-second pause to reposition and reset is better than continuing with severely degraded compressions.

7. Wrong hand placement for age

Operator cause: Using adult two-hand technique on an infant; placing hands over the xiphoid process (bony tip at the sternum's end); compressing the upper sternum
Outcome: Liver laceration; reduced ventricular compression; lower cardiac output
Recognition: Hands positioned below the nipple line, or above the lower half of the sternum
Recovery: For adults: two hands, lower half of sternum, fingers interlaced. For children: one or two hands, lower half of sternum. For infants: one-hand technique (lone rescuer) or two encircling thumbs (two rescuers — preferred), lower half of sternum just below nipple line. Never compress the xiphoid process.

CPR readiness checklist

Take a certified CPR and AED course (American Heart Association, American Red Cross, or National Safety Council) — recertify every 2 years
Practice rescue breathing technique with a pocket mask or face shield quarterly
Locate AEDs at home, workplace, gym, and other frequently visited locations
Confirm every household member 12 years and older knows hands-only CPR — 3 minutes to teach the basics
Stock a CPR pocket mask in your home medical kit and personal emergency bag
Know the distinction: adult = puberty-age or older; child = 1 year to puberty; infant = under 1 year
Memorize rate (100–120/min) and depth (adult ≥2 in / 5 cm; child ~2 in / 5 cm; infant ~1.5 in / 4 cm)
Review hands-only vs. full CPR criteria — children and drowning victims need rescue breaths

Stop immediately for these conditions

Do not begin or immediately stop CPR if: a valid DNR order is visible or presented; the scene is unsafe; rigor mortis is present (stiff, resistant muscles throughout the body — not the same as muscle tightening at death); fixed lividity is present (dark purple-red mottling fixed to the underside of the body, visible even when position is changed — indicates blood has pooled and solidified); injuries are incompatible with life. These signs indicate irreversible biological death — CPR cannot reverse them and consumes rescuer resources needed elsewhere.

With cardiac arrest managed and Return Of Spontaneous Circulation established, the priority shifts immediately to post-ROSC shock management — the heart can re-arrest within minutes, and positioning, temperature control, and circulation monitoring are critical. For the full patient assessment framework that CPR fits within, see emergency medical assessment. For building the training foundation that makes these procedures automatic under stress, see medical training.

If your household includes anyone with a cardiac history, high-risk chronic condition, or who takes medications that affect heart rhythm, coordinate the CPR and AED plan with chronic conditions management — medication-specific resuscitation considerations may apply.

Sources and next steps

Source hierarchy

AHA 2025 Emergency Cardiovascular Care (ECC) Guidelines — Parts 6 (Pediatric BLS) and 7 (Adult BLS): ahajournals.org
Wilderness Medical Society (WMS) CPR in the Wilderness guidelines: wms.org

Next 3 links

Post-ROSC shock management — what to do immediately after the heart restarts; re-arrest risk, positioning, and circulation monitoring
Emergency medical assessment — the ABCDE framework that CPR fits within during a full patient assessment
Medical training — how to build the hands-on repetition that makes these procedures automatic under stress

Legal / regional caveats

Good Samaritan laws protecting bystander CPR vary by jurisdiction. In the United States, all 50 states have Good Samaritan statutes covering lay-rescuer CPR; check local laws when outside the US. DNR orders and advance directives are legally binding — honor them when clearly presented.

Last reviewed: 2026-05-24 Safety stakes: Life-safety