ABCDE assessment and stabilisation of the acutely ill child

Overview & Definition

The ABCDE approach is a structured primary survey that finds and fixes life threats in the order they will kill the child: a blocked airway kills before failing breathing, failing breathing kills before shock, shock kills before a falling conscious level. You do not need a diagnosis to start. The moment you find a threat at any step, you treat it, then you return to A and reassess the whole child. This treat-as-found, reassess-from-A discipline is what turns a checklist into resuscitation. [9] [10]

ABCDE is a stabilisation method, not a diagnostic method. It tells you which organ system is failing now and keeps the child alive while you work out why. The cause-specific pathway (sepsis, asthma, anaphylaxis, diabetic ketoacidosis, poisoning, trauma) takes over once the immediate threats are controlled, and reassessment never stops. A child can be perfectly stable on the primary survey and still need urgent work-up because the missed diagnosis is dangerous; equally, an unstable child needs treatment before the diagnosis is certain. [3] [9]

[9] [10]

It sits between two other tools. The paediatric assessment triangle is the hands-off first impression from the doorway that tells you to start ABCDE. The focused secondary assessment (full history and head-to-toe examination) comes after the primary survey has made the child safe. ABCDE is the hands-on middle layer where most lives are saved or lost. [9]

[3] [9]

Classification

Each step of the survey answers one question and has one first action. Read the table as the contract for what you do at each letter. [9]

[9] [10] [9]

A useful companion is the staged description of how sick the child is. Respiratory distress means effort is increased but breathing still moves air. Respiratory failure means oxygenation or ventilation is ineffective and appearance is often abnormal. Compensated shock means perfusion is poor but blood pressure is maintained. Decompensated shock adds hypotension and falling consciousness. Cardiorespiratory arrest means unresponsive, no breathing, no pulse. Each stage changes the urgency and the first action, and the boundary is clinical, not a single number. [3] [9]

[9] [10]

Epidemiology & Risk Factors

Children deteriorate fast because their physiology is built for compensation, and the settings where deterioration is missed share the same features: a young infant, a delayed or repeated presentation, a barrier to communication, and a service with limited monitoring or rescue. The practical point is that risk context changes the tempo of your survey and the threshold for escalation, not the order of the letters. [3] [9]

Young infants deserve particular caution. A neonate or infant under three months can have serious bacterial infection, metabolic disease or a duct-dependent cardiac lesion and present without fever, with only poor feeding, reduced tone or a change in behaviour. Treat these as high-risk presentations: lower your threshold to start ABCDE, check bedside glucose, and seek senior review early. [3] [9]

[3] [9]

The limits of individual signs are evidence-based, and examiners test them. Capillary refill time is useful but its sensitivity and specificity for serious illness are modest, and the result depends on technique, site, ambient temperature and the operator. Blood pressure is maintained until late in paediatric shock, so a normal pressure never excludes it. Early-warning scores depend on the chart, complete observations and the response system around them. None of these, used alone, should end your survey. [2] [3]

Pathophysiology

Children compensate well and then collapse. To understand ABCDE you need to know why. A child in early shock or respiratory failure does not look as bad as an adult at the same stage, because heart rate, breathing effort and vascular tone rise to protect blood pressure and cerebral perfusion. This buys time, but it hides the problem and it costs reserve. When reserve runs out, the fall is steep. [3] [9]

Cardiac output in children is heart-rate dependent. Neonates and young infants have a relatively fixed stroke volume, so they maintain output mainly by raising heart rate. Tachycardia and vasoconstriction can preserve blood pressure and wakefulness for a while, but they also raise oxygen demand. In a child who is hypoxic or deteriorating, a falling or abnormally low heart rate is an ominous sign of decompensation, not a sign that the child is calming down. Waiting for hypotension to diagnose circulatory failure is a classic and dangerous error. [1] [3]

[1] [3]

The respiratory system has the same shape. Smaller airways, a compliant chest wall and a higher metabolic rate mean a young child runs out of respiratory reserve quickly. Increasing effort at first moves air and maintains oxygenation; as the muscles fatigue, air entry falls while visible effort may actually lessen. This is the tiring child, and it is one of the most dangerous moments in the survey: a quieter chest after marked effort is failure until you prove otherwise. [1] [9]

Oxygen delivery depends on effective ventilation, arterial oxygen content, cardiac output, tissue perfusion and cellular use. A failure at any of these can make the child acutely ill, which is why the survey moves airway to breathing to circulation to brain in that order: each step protects the next. A child who is blue, mottled and limp is not showing three separate problems but one failing system seen through several signs. [3]

Disability fails because the brain is sensitive to hypoxia, hypercapnia, hypoperfusion, hypoglycaemia, seizures and toxins. A change in appearance or interaction is therefore a late-but-urgent signal that something upstream in A, B or C is failing, or that a metabolic or toxic threat is present. Reading disability as a stand-alone neurological problem, rather than as a window onto the whole child, is a common error. [7] [9]

Clinical Presentation

Begin before you touch. From the doorway, note interaction and arousability, tone and posture, cry or speech, visible and audible breathing effort, colour, and the caregiver's manner. Any of these can trigger ABCDE. The goal is to describe what you see, not to label it. "This child is pale, floppy, grunting and barely responsive" tells the team more than "this child looks septic". [9]

What each step shows when it is failing

At A, a threatened airway may show abnormal sound (stridor, snoring, gurgling, silence), tripoding or a preferred posture, inability to phonise, or obstruction by secretions or blood. A child fighting to keep an airway upright must not be laid flat or agitated; summon airway expertise before the airway is lost. [9]

At B, look for a rate outside the range for age and condition, increased work (recession, nasal flaring, grunting, accessory muscle use), reduced or unequal air entry, and a credible oxygen-saturation trend. Respiratory distress becomes respiratory failure when effort is high but air entry is poor, or when effort falls while the child looks worse. Oxygen saturation is a single input: confirm the signal is reliable and matches the child, because oximetry does not measure ventilation and may overestimate oxygenation in darker skin. [1] [9]

At C, integrate pulse rate and quality, skin colour and temperature, capillary refill measured with the technique stated, blood pressure, mental state and urine output. Warm skin with a bounding pulse does not exclude shock; cold skin with weak pulses does not confirm one type. Hypotension is a late sign. Weigh the whole picture, and treat the direction of change. [2] [3]

At D, use AVPU for speed (Alert, responds to Voice, responds to Pain, Unresponsive) and convert any V, P or U, or a persistently concerning Alert child, to a formal age-adapted Glasgow Coma Scale. Check pupils, posture, tone and movement, time any seizure, and check bedside glucose whenever consciousness is altered, a seizure is present, or shock, poor intake or a toxic or metabolic cause is possible. [7] [9]

At E, look for rash, injury, bruising, bleeding, a device problem or abnormal temperature while keeping the child warm and covered. The skin often holds the diagnosis (purpura, a burn, an injection site, a blocked tracheostomy), and it may hold safeguarding evidence. [9]

[1] [9]

Differential Diagnosis

Build the primary-survey differential in a fixed order: what can kill the child now, what is most likely, what is reversible, and what is most harmful to miss. ABCDE does not name the disease; it names the failing system and the immediately reversible threats. Keep the dangerous causes open until focused history, examination, targeted tests and response narrow them. [3] [9]

[3] [9]

A more compact and widely taught frame is the reversible causes to actively seek during the survey: hypoxia, hypovolaemia, hypoglycaemia and hypothermia (the low Hs), and tension pneumothorax, tamponade, toxins and thrombosis (the mechanical and toxic Ts). These are the threats that a single correct action can reverse, so they belong in the front of your mind at every pass. [9] [10]

[3] [9]

A defensible synthesis sounds like this: "This child has ineffective breathing with falling air entry and reduced interaction, so I am treating respiratory failure with oxygen and ventilation support. My leading threats are severe lower-airway or parenchymal disease with fatigue, but I am keeping sepsis, a cardiac cause, a metabolic problem and a toxin open. I will reassess after ventilation improves, and I will not fix on one diagnosis until the trend supports it." [9]

Clinical & Bedside Assessment

The survey is hands-on but not rough. Keep the child with the caregiver when safe, observe before handling, and examine the least distressing parts first. Distress raises the respiratory rate and heart rate, worsens behaviour, and can destabilise a threatened airway, so a calm sequence is part of the treatment. None of this delays treatment of an unstable child. [9]

A - Airway

Assess whether the airway open and protected. Listen for abnormal sound or an ominous silence. Look for obstruction, secretions, blood or vomit, and assess whether the child can maintain the airway and protect it (can they phonise, swallow, clear secretions?). First actions are airway positioning (head-tilt chin-lift, or jaw thrust if trauma is possible), suction of removable obstruction, and an airway adjunct only if tolerated. Summon definitive airway expertise before the airway fails, not after. [9]

B - Breathing

Count the respiratory rate under stated conditions and compare with the age-appropriate range. Assess effort, effectiveness, symmetry, air entry and fatigue. Attach a credible pulse oximeter and, in serious illness, consider capnography. The first action in respiratory, circulatory or neurological failure is to give high-flow oxygen. If breathing is ineffective, support it with bag-mask ventilation: an open airway, a good seal, an appropriate size, gentle chest rise, and a rate for age. Effective ventilation is judged by chest movement, air entry, improving colour and interaction, not by the monitor alone. [1] [9]

C - Circulation

Assess pulse rate and quality at central and peripheral sites, skin colour and temperature, capillary refill with site, compression time and ambient temperature stated, blood pressure, mental state and urine output. Look for bleeding and check device function. First actions are to control obvious loss, gain vascular access without allowing repeated failed attempts to delay care, and treat shock with fluid aliquots. Diagnose shock from the whole picture, never from blood pressure or capillary refill alone. [2] [3]

D - Disability

Use AVPU for speed. The Royal Children's Hospital Melbourne altered-conscious-state guideline directs any V, P or U response to a formal Glasgow Coma Scale; record AVPU and reassess after immediate care. Perform an age-adapted GCS when concern persists despite an apparently Alert child, and never convert an AVPU letter into an assumed GCS number. Check pupils, posture, tone and movement, time any seizure, and check bedside glucose. Protect the airway and breathing while the local pathway is activated. [7] [9]

E - Exposure

Expose only what you must, look for rash, injury, bruising, bleeding, swelling or a device problem, then cover and warm the child again. Record objective findings and the child's spontaneous words accurately, because exposure often reveals both the diagnosis and safeguarding evidence. [9]

[9]

Focused history in parallel

While stabilisation proceeds, take a focused history using a SAMPLE frame: Symptoms, Allergies, Medications, Past history (including baseline and devices), Last meal, Events leading up. Begin with the caregiver: "What is different from usual, and what worries you most?" Add onset, pace, breathing, feeding, urine output, fever, rash, collapse, seizure, exposure, ingestion and trauma. Ask adolescents privately about substances, self-harm and pregnancy when safe. Use a professional interpreter whenever needed. [9]

Synthesis after every pass

After each pass, say and document one sentence: what is failing now, what direction the child is moving, what you expected from the last action and what actually happened, and what you will do next. This spoken synthesis is what examiners listen for, and it is what keeps a team coordinated during rapid change. [8] [9]

Investigations

Stabilise first, then order a test for a named question. A useful test finds an immediately reversible cause, quantifies failing physiology, separates urgent pathways, or changes the destination. A normal panel cannot overrule a child who is worsening. [9]

[9]

Interpret urgent tests as physiology and trend, not binary reassurance. A blood gas shows whether ventilation and acid-base state are failing and whether the pattern points to respiratory, circulatory, metabolic or toxic causes; one gas never replaces the child. Lactate reflects perfusion or metabolic stress and should fall with effective resuscitation; a normal lactate does not exclude shock. Blood count and inflammatory markers cannot rule out serious infection in a high-risk child. Confirm an unexpected point-of-care glucose when feasible, but never let confirmation delay treatment of a dangerous low. [7] [9]

[9]

Management — Resuscitation

A worrying first impression starts ABCDE immediately. State that you are concerned, call the appropriate team, name a leader, allocate roles, use closed-loop communication, prepare age- and weight-appropriate equipment, and monitor continuously. Treat each problem when found, then reassess from A. History, sampling and cause-specific treatment proceed in parallel only when they do not delay resuscitation. [9]

[9] [9]

Oxygen: phase and population matter

The American Heart Association 2020 Paediatric Life Support guideline states that a child in respiratory, circulatory or neurological failure should receive high-flow oxygen initially, followed by titration. For a previously healthy child, target an oxygen saturation of 94 to 98%, using the lowest inspired fraction that achieves at least 94%. These are acute-rescue facts. They are not universal targets for cyanotic congenital heart disease, chronic respiratory support or post-resuscitation care. Confirm a credible oximeter signal before trusting the number. [9]

Circulatory support: a ceiling, not a target

First decide whether the child has shock using the whole circulation assessment. Then consider the likely shock type, whether hypotension is present, and whether ventilation, critical care and vasoactive rescue are available. Decide what improvement you expect before giving fluid, reassess after each aliquot, and stop for overload or no benefit. The Surviving Sepsis Campaign 2026 children's guideline supports up-front fluid boluses in septic shock with careful reassessment, while cautioning against fluid accumulation. The first-hour fluid total is a ceiling, never a target. [3] [11]

The FEAST trial is the cautionary anchor. In African children with severe febrile illness, saline or albumin bolus increased early mortality compared with no bolus. It does not prove that every bolus is harmful everywhere; it proves that a fluid algorithm cannot be transplanted across populations and rescue resources. Apply fluid strategy to the child in front of you, and call for critical-care or retrieval help early if vasoactive support may be needed. [4]

Disability: glucose and seizure

Check bedside glucose whenever altered consciousness, seizure, shock, poor intake or a toxic or metabolic cause is possible. If the point-of-care result is dangerous-low, correct it now through the active age- and context-specific pathway, then recheck and investigate the cause; confirm an unexpected result when feasible, but never delay treatment. Under the AHA 2020 guideline and local pathways, an ongoing convulsive seizure is status epilepticus and activates first-line treatment at five minutes; do not wait for two doses to fail. [6] [7] [9]

Working weight when immediate weighing is unsafe

Use a measured weight if it can be obtained immediately without delaying care. Otherwise announce and document one temporary working weight in kilograms, including its source, method and time. Follow the local protocol: a recent reliable measured weight, a credible caregiver estimate, or the service's trained length-and-habitus method. Published methods vary in accuracy and are not interchangeable, and total body weight is not correct for every drug or device, so always confirm with the local paediatric cognitive aid and re-weigh at the first safe opportunity. [5]

When ABCDE becomes advanced life support

If the child is unresponsive with absent or agonal breathing and no central pulse, move straight into the paediatric arrest algorithm rather than completing the survey. The AHA 2020 and ILCOR 2020 paediatric life support sources anchor the key arrest doses: intravenous or intraosseous adrenaline 10 micrograms per kilogram (0.1 mL/kg of 1:10,000 adrenaline) every three to five minutes, and defibrillation at 4 joules per kilogram for a shockable rhythm. These are anchors for the escalation point, not a full arrest algorithm; the complete pathway lives in the paediatric basic and advanced life support topic. [9] [10]

[9]

Management — Definitive & Stepwise

After immediate resuscitation, move into the pathway for the likely cause without stopping reassessment. This hub does not reproduce the full shock, ventilation, status, antimicrobial, toxicology or glucose algorithms; treat the most reversible dangerous problem first while keeping other serious causes open. [3] [9]

[8] [9]

Improvement must make sense across several findings. An open airway must also remain open. Less work of breathing is reassuring only when air entry and interaction improve. Better blood pressure does not prove adequate perfusion. A corrected glucose needs a documented recheck and a plan for the cause. Reassess after each action and meaningful change rather than waiting for a fixed interval. [2] [9]

Early PICU and retrieval consultation

Call PICU or retrieval when the child may need support your service cannot reliably provide, not after every local option has failed. Discuss the likely support, present monitoring and access, equipment and staff limits, transport time and weather, the safest destination, the escort, expected deterioration and what to do if transfer is delayed. Exact referral thresholds, escort arrangements, transport mode and accepting service remain local or regional. [9]

[8] [9]

A structured handoff program reduced medical errors and preventable adverse events in a multicentre study of resident physicians; the principle generalises to acute handover, where the loss of trend, timed actions and contingency is a recurrent source of harm. Keep the caregiver informed, speak to the child at their developmental level, use a professional interpreter when needed, and check understanding. [8]

Specific Subtypes & Scenarios

The survey stays the same, but age, presentation, baseline and setting change what you look for and how early you escalate. In each scenario: stabilise first, identify what is failing, activate the correct pathway, and state which facts are specific to that source or setting. [9]

[3] [9] [9]

Complications & Pitfalls

Most harm begins when assessment stops too early. A normal number, a convenient explanation or a brief response is accepted as the answer, so the child is not reassessed. Prevent this by recording the current problem, the serious alternatives, the expected result, the actual response and the next escalation action. [2] [9]

[2] [4] [8] [9]

Watch for anchoring on the referral diagnosis, ordering tests only to confirm it, and carrying forward a label that silences bedside concern. After stabilisation, look actively for harm from treatment: airway or access complications, fluid overload, heat loss, repeated sampling, medication or device error, and pressure or restraint injury. The fact that the child did not arrest does not prove an intervention was harmless. [4] [9]

[3] [9]

Prognosis & Disposition

Disposition follows the trend and response, not one reassuring observation. Consider the child's age and reserve, the duration and severity of organ dysfunction, reversibility, treatment harm, local support, transport risk, and whether the family can carry out the plan. [3] [9]

[9]

A useful safety net states what change to watch for, how urgently to act, and exactly where or how to get help. It also states when review will occur, who owns pending results, and what to do if access is difficult. "Return if worried" alone is not enough. Check understanding with teach-back, document it, and connect the family to the medical home, primary care or community team. After a critical event, explain what happened and what remains uncertain, invite questions, and consider debriefing for the child, family and team. [9]

Special Populations

Adapt how you observe, communicate and examine, but never lower the standard for recognising deterioration. Evidence is sparse for recognition tools in disability, neurodiversity, technology dependence and many low-resource settings; present these adaptations as safer practice, not as proven improvements in diagnostic accuracy. [9]

[9]

Safeguarding runs in parallel with medical care, but immediate stabilisation and safety come first. Ask only necessary open, non-leading questions. Explain confidentiality and information sharing, document objective findings and spontaneous words, preserve evidence when safe, and use the local safeguarding pathway. Reporting thresholds, consent rules and agencies differ by Australian state or territory, UK nation, US state and Canadian province or territory. [9]

Evidence, Guidelines & Regional Differences

What the evidence can and cannot support

The ABCDE structure itself is consensus: the AHA 2020 Paediatric Basic and Advanced Life Support guideline and the ILCOR 2020 Paediatric Life Support consensus both teach a primary survey that finds and treats life threats in the airway-breathing-circulation order and returns to reassess. The order of the letters is not in dispute; the doses, targets and thresholds attached to each step are source- and population-specific. [9] [10]

[4]

The Surviving Sepsis Campaign 2026 children's guideline supports early recognition and first-hour fluid resuscitation with vasoactive support for septic shock, with explicit attention to fluid balance. It is a global specialist guideline whose details (crystalloid choice, aliquot size, vasoactive first agent) are read alongside local resources and the child's shock type. [11]

Capillary refill has modest diagnostic value and is highly technique-dependent, early-warning scores depend on the whole response system, and pulse oximetry can overestimate oxygenation in darker skin. There is no universal vital-sign range, oxygen target, fluid volume, glucose threshold or weight-estimation formula that fits every child. Attach each rule to its population, purpose, conditions and jurisdiction. [1] [2]

Jurisdictional implementation

[9] [9] [9] [9] [4]

Exam Pearls

[9] [10]

Viva: the tachypnoeic child becomes quiet

Do not say "improved" until you reassess effectiveness. Recheck air entry, work, respiratory rate, a credible saturation, interaction, perfusion and glucose. Less effort with poorer air entry or reduced interaction means fatigue and impending failure. Support breathing, state the improvement you expect, call airway or critical-care help, and reassess from A.

[1] [9]

Viva: when does ABCDE become a cardiac arrest algorithm?

When the child is unresponsive with absent or agonal breathing and no central pulse. Move directly into the paediatric arrest algorithm: high-quality chest compressions, ventilation with oxygen, and the arrest-dose anchors of intravenous or intraosseous adrenaline 10 micrograms per kilogram every three to five minutes and defibrillation at 4 joules per kilogram for a shockable rhythm. Do not finish a survey of an arrested child.

[9] [10]

Structured oral: rural retrieval of a deteriorating child

State the current ABCDE problem and the treatment under way. Ask what monitoring, airway, vascular-access, staff and transport resources are available. Call retrieval early, agree the destination, the treatment to continue, the expected response, the deterioration plan and the handover, and explain uncertainty and transport delay to the family. Do not wait until all local options have failed.

[9] [3] [9] [1] [2] [3] [4] [7] [8] [9]

References

1. [1]Fleming, Susannah Normal ranges of heart rate and respiratory rate in children from birth to 18 years of age: a systematic review of observational studies Lancet (London, England), 2011.PMID 21411136
2. [2]Fleming, Susannah The Diagnostic Value of Capillary Refill Time for Detecting Serious Illness in Children: A Systematic Review and Meta-Analysis PloS one, 2015.PMID 26375953
3. [3]Bjorklund, Ashley Pediatric Shock Review Pediatrics in review, 2023.PMID 37777656
4. [4]Maitland, Kathryn Mortality after fluid bolus in African children with severe infection The New England journal of medicine, 2011.PMID 21615299
5. [5]Young, Kelly D Weight Estimation Methods in Children: A Systematic Review Annals of emergency medicine, 2016.PMID 27105839
6. [6]McIntyre, John Safety and efficacy of buccal midazolam versus rectal diazepam for emergency treatment of seizures in children: a randomised controlled trial Lancet (London, England), 2005.PMID 16023510
7. [7]Faustino, E Vincent S Hypoglycemia in critically ill children Journal of diabetes science and technology, 2012.PMID 22401322
8. [8]Starmer, Amy J Changes in medical errors after implementation of a handoff program The New England journal of medicine, 2014.PMID 25372088
9. [9]Topjian, Alexa A Part 4: Pediatric Basic and Advanced Life Support 2020 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Pediatrics, 2021.PMID 33087552
10. [10]Maconochie, Ian K Pediatric Life Support: 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations Circulation, 2020.PMID 33084393
11. [11]Weiss, Scott L Surviving Sepsis Campaign International Guidelines for the Management of Sepsis and Septic Shock in Children 2026 Pediatric critical care medicine : a journal of the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies, 2026.PMID 41869844