Overview

The ABCDE acronym

An ABCDE assessment is vital for critically ill or severely unwell people, such as people with sepsis, to stabilise them to buy time before confirming a diagnosis. Cardiac arrests are often preceded by signs that can be picked up during this assessment. The ABCDE acronym prioritises the order of assessment and treatment based on what problems are most likely to lead to death the quickest:

  • Airways: airway obstruction can lead to cardiac arrest
  • Breathing: impaired gas exchange can lead to hypoxia
  • Circulation: poor circulation can cause organ ischaemia
  • Disability: altered consciousness levels can suggest clues
  • Exposure: rashes, wounds, and other clues may be found

In cases of cardiac arrest, life support algorithms take precedence over the ABCDE approach and should be done instead.

Key points

  • Get help early: you do not have to manage this alone and should have help from others.
  • Treat life-threatening problems first: before moving onto the next part of the assessment. 
  • Delegate tasks: use all team members for efficient assessment and treatment.
  • Allow time to reassess: each intervention may take a few minutes to work. Keep this in mind when reassessing or moving on but avoid spending too long before seeking help.
  • Continue repeating the ABCDE assessment: until senior help arrives.
  • Document but do not delay: document assessments and interventions promptly without delaying treatment.

Airways, breathing, and circulation

Hypoxia can lead to permanent damage of crucial organs, including the heart, brain, and kidneys, leading to cardiac arrest. Therefore, problems impairing oxygenation are crucial:

  • Airway obstruction: prevents oxygen entry into the lungs.
  • Breathing problems: hinders gas exchange (e.g. asthma, pulmonary oedema, pneumothorax)
  • Circulatory problems: impairs oxygen delivery around the body (e.g. arrhythmia, shock, haemorrhage)

Disability and exposure

Disability assesses consciousness and neurological problems, which could suggest serious illness and may find underlying causes (e.g. hypoglycaemia, intracranial bleeds, drug causes etc.). Exposure assesses the patient entirely, looking for signs of underlying causes, such as bruising, wounds, rashes, and abdominal tenderness.

Moving through the ABCDE acronym

Problems are tackled as they arise, with continuous reassessment after each intervention. This involves, examining them, arranging tests, and giving treatment. Only move on to the next letter once the current one has been dealt with. For example, do not move onto circulation unless you have assessed and managed breathing first. If this is not possible, seek help immediately.

After completing a full ABCDE cycle, it is repeated until the patient stabilises. 

During each letter, the ‘VETO-R’ acronym can help with remembering what to do:

  • Vital signs: oxygen saturation, respiratory rate, pulse, blood pressure, temperature, consciousness level
  • Examination: airway patency, cardiorespiratory signs (e.g. murmurs, crackles), neurological deficits, rashes, wounds, abdominal tenderness etc.
  • Tests: blood tests, urine/sputum samples, X-rays, ECGs, urine output etc.
  • Optimisation: intervening to solve the problem, such as giving high-flow oxygen
  • Reassess: has this improved? If so, move on to the next letter and if not, get help.

Another acronym that follows the same format is ‘OATS-R’: observations, assessment, tests, sort it out, and reassess.

In reality, the assessment and treatment of the patient occur simultaneously.

OSCE Tips and Scenarios

OSCE Scenarios

Some ABCDE assessment stations involve candidates performing their steps on a mannequin, commenting on their findings (or what they would expect to find) and requesting tests and treatment when problems arise. Due to time constraints, examiners may prompt candidates to move on to the next step instead of reassessing and holding on to test results until the end. 

These stations assess the ability to:

  • Conduct a systematic, focused examination with confidence, ensuring patient comfort and dignity.
  • Identify and comment on findings/what would be found as they proceed.
  • Interpret any provided data accurately within the clinical context.
  • Propose likely diagnoses based on findings accurately.
  • Respond confidently and accurately to questions about further management steps.

First Steps

Patient handover

You may receive a patient handover from another healthcare professional. Introduce yourself fully with your name and role and take note of key details, including their name, age, background, and reason for handover.

Danger

  • Check for immediate dangers (e.g. spills, blood, medical equipment etc.) before approaching the patient.

Response

Check if the patient is responsive by asking if they are okay:

  • Responds normally: the airway is patent. To be able to speak, air must move through the vocal cords. Being short of breath does not mean the airway is definitely non-patent (e.g. wheezing, which occurs due to lower airway constriction). 
  • Responds with difficulty: the airway may be at risk, such as stridor (suggesting upper airway compromise). 
  • No response: critical illness is likely, initiate CPR and call the arrest team.

Airway

Vital signs (observations) 

n/a

Examination (assessment)

Check if the airway is patent – use look, listen, and feel:

  • Look for chest/abdomen movements and around and inside the mouth:
    • Signs of causes: such as foreign bodies, secretions, oedema in anaphylaxis
    • Signs of potential/actual obstruction: such as accessory muscle use paradoxical chest and abdomen movements (see-saw breathing, where the abdomen is drawn in as the chest attempts to expand if a person’s airway is obstructed), foreign bodies, secretions, blood, and vomit, 
  • Listen to the patient’s breathing overall:
    • Patent: the patient can talk normally and has no noisy breathing
    • Partial airway obstruction: noisy breathing such as snoring, stridor, wheezing, or gurgling.
    • Completely obstructed: no breath noises (indicates complete obstruction), Glasgow coma score (GCS) ≤8, the patient has aspirated.
  • Feel for airflow at the mouth and nose on your cheek.

Tests

n/a

Optimisation (sort it out)

Give oxygen immediately and consider initial ventilatory support:

  • High-flow oxygen via a non-rebreathe mask: this can buy some time before the patient desaturates.
  • No/poor respiratory effort: requires two people. One person holds the face mask while performing a jaw thrust while the other squeezes the bag 10 times per minute. This can be continued if airway adjuncts are used.

Perform basic airway manoeuvres and repeat look, listen, and feel: check if airway obstruction has resolved after performing these:

  • Head-tilt and chin-lift: place one hand on the patient’s forehead and tilt the head back and place the fingertips of the other under the patient’s chin and lift. Avoid this in suspected/confirmed cervical spine injury. 
  • Jaw-thrust: place your fingertips behind the angle of the mandible on both sides and the thumb on the front side of the jaw under the mouth and lift upwards, keeping the mouth slightly open. This is safer in cervical spine injuries.

Consider treating obvious obstruction:

  • Magill forceps – to remove obvious obstructions (e.g. dentures, debris etc.)
  • Suction – in parts that can be seen directly (for blood, vomit, secretions etc.)
  • Intramuscular adrenaline – for anaphylaxis

Maintain the airway: consider airway adjuncts and/or intubation:

  • Oropharyngeal airway (Guedel): these work by fitting between the tongue and hard palate. Insert this upside down (to avoid pushing the tongue back), then turn this around once inside. Semi-conscious patients may gag, and this could provoke vomiting or laryngospasm. If a patient cannot tolerate these, do not insert them. 
  • Nasopharyngeal airway: avoid in significant head injury. Generally tolerated better in semi-/fully conscious people and useful for seizures.
  • Intubation: especially if GCS ≤8 (‘GCS 8, intubate’). Put out a crash call or contact the anaesthetist.

Reassess

Reassess before moving on – has this improved?

  • If yes: move on
  • If not: get help.

Breathing

Vital signs (observations)

Check relevant vital signs:

  • Respiratory effort: if no respiratory effort, call the arrest team.
  • Oxygen saturations: 94-98% in healthy people, only 88-92% in people with COPD who are known to be CO2 retainers. Not everyone with COPD has targets of 88-92%.
  • Respiratory rate: normally 12-20 /min

Examination (assessment)

Inspect the patient overall:

  • Cyanosis: suggesting poor circulation (e.g. shock) or poor oxygenation (e.g. lung disease)
  • Dyspnoea: pursed lips, accessory muscle use, ‘tripod position’, cannot finish sentences
  • Stridor: this suggests upper airway narrowing (e.g. anaphylaxis, inhaled foreign body)
  • Abnormal breathing: such as Kussmaul respiration seen in metabolic acidosis (e.g. diabetic ketoacidosis, Addisonian crisis)

Inspect the neck:

  • Tracheal deviation: deviates away from the affected side in tension pneumothorax and large effusions. Deviates towards the affected side in lobar collapse and pneumonectomy. 
  • Jugular venous pressure: normally <4 cm vertically above the sternal angle

Inspect the chest:

  • Chest movements: is expansion equal on both sides? Are accessory muscles being used? 
  • Chest deformities: they can increase the risk of deteriorating breathing.

Palpation and percuss the chest:

  • Apex beat displacement: may suggest heart failure, pneumothorax, effusions etc.
  • Chest expansion: is this equal on both sides?
  • Percussion: is this equal on both sides? Hyper-resonance can suggest pneumothorax, dullness can suggest consolidation, effusions, tumours etc.

Auscultate the chest from the front and back:

  • Presence on both sides: are breath sounds equal on both sides?
  • Quiet/absent sounds: could suggest pneumonia, pneumothorax, collapse, effusions, tumours etc.
  • Abnormal breath sounds: bronchial breathing (pneumonia), wheezing (COPD, asthma, bronchiectasis, foreign body), crackles (pneumonia, bronchiectasis, pulmonary oedema).

Check the calves for deep vein thrombosis:

  • Calf swelling/tenderness: their presence may suggest a pulmonary embolism if breathing is impaired.

Tests

Arrange appropriate tests – think through them with the BOXES acronym:

  • Blood tests:
    • Arterial blood gas (ABG): if oxygen saturation is low, GCS is low, or dyspnoeic.
  • X-rays and imaging:
    • Chest X-ray: for suspected lung problems (e.g. pneumonia, pulmonary oedema)

Optimisation (sort it out)

Sit the patient upright and give oxygen:

  • All critically unwell people: 15 L/min O2 via a non-rebreathe mask including people with COPD:
    • Hypoxia kills and the risk of harm from hypoxia significantly outweighs the risk of reduced respiratory drive.
    • Once the patient’s oxygen saturation has improved and ABG results are obtained, the oxygen can be adjusted accordingly if needed.
  • Poor respiratory effort: use a bag valve mask to support breathing and force air into the airways.
  • Consider non-invasive/invasive ventilation: such as CPAP in acute pulmonary oedema or BiPAP in acute COPD.

Treat underlying causes if possible:

  • Such as nebulised salbutamol and ipratropium for asthma and COPD, naloxone for opiate overdose, IM adrenaline for anaphylaxis, needle decompression for pneumothorax etc. 

Reassess

Reassess before moving on – has this improved?

  • If yes: move on
  • If not: get help.

Circulation

Vital signs (observations)

Check relevant vital signs:

  • Pulse rate, rhythm, and volume:
    • No palpable pulse: call the arrest team.
    • Irregular pulse: may suggest arrhythmia (e.g. atrial fibrillation)
    • Thready/weak pulse: may suggest hypovolaemia (e.g. shock)
  • Blood pressure and trends: is it decreasing?
  • Central capillary refill time: normally <2 seconds
  • Temperature: normally 36°C – 37.5°C

Examination (assessment)

Inspect the patient overall:

  • Colour: such as pallor (anaemia, haemorrhage, poor perfusion), cyanosis (poor perfusion, poor oxygenation), mottled skin (shock). 
  • Fluid overload: such as sacral and ankle oedema, ascites etc.
  • Dehydration: such as cool peripheries, dry mucous membranes, reduced jugular venous pressure etc.

Listen to their heart sounds:

  • Added heart sounds: such as muffled/quiet heart sounds (cardiac tamponade), murmurs, S3 (suggesting fluid overload such as heart failure), pericardial rub (pericarditis)

Check their fluid balance and urine output:

  • In vs out: compare intake (fluids, food etc.) and output (urine, catheters, drains, vomit etc.)
  • Reduced urine output (oliguria): <0.5 mL/kg/hour in an adult

Tests

Get early venous access:

  • Insert two wide-bore (16 G) cannulae: this allows increased fluid delivery if needed.

Arrange appropriate tests – think through them with the BOXES acronym:

  • Blood tests:
    • ABG or venous blood gas (VBG): for respiratory/metabolic acidosis/alkalosis
    • Full blood count (FBC): for anaemia, leukocytosis, or thrombocytopenia
    • Blood cultures: if febrile/infection is suspected.
    • C-reactive protein (CRP): for inflammation, may be elevated in infection (e.g. sepsis)
    • Urea and electrolytes (U&Es), calcium, magnesium, and phosphate: for renal disease and electrolyte imbalances
    • Liver function tests (LFTs): for liver disease
    • Thyroid function tests (TFTs): for thyroid dysfunction
  • Blood tests depending on likely cause:
    • Coagulation studies, cross-matching, group and screen for haemorrhage:
      • Cross-matching: ABO and Rhesus matching can take around 30 minutes, but looking for antibodies in the recipient takes up to 1 hour.
      • Group and screen: done where there is a possibility of requiring transfusion and takes around 1 hour.
    • Troponin: for acute coronary syndrome
    • D-dimer: for pulmonary embolism/deep vein thrombosis
    • Toxicology: such as for paracetamol levels
  • Orifice samples to test:
    • Urinary pregnancy test: all people of childbearing potential with abdominal and/or pelvic pain or gynaecological symptoms
    • Samples for culture (e.g. sputum, urine, faeces etc.)
  • ECGs:
    • 12-lead ECG: for causes such as acute coronary syndrome or arrhythmia
    • Continuous cardiac monitoring: for patients that are critically unwell or require correction of severe electrolyte abnormalities.
  • Monitor fluid balance and consider catheterisation.

Optimisation (sort it out)

If hypotensive, give a fluid challenge – a bolus of 0.9% normal saline or Hartmann’s solution:

  • 500 mL if there is no significant risk of fluid overload.
  • 250 mL if there is a risk of fluid overload (e.g. heart failure or frail patients)

Assess fluid challenge response using pulse, blood pressure, and urine output. Aim for a systolic blood pressure of 100 mmHg:

  • Full response: consider maintenance fluids.
  • Responds but blood pressure falls again: consider repeating up to 4 times – maximum of 2L or 1L in people at risk of fluid overload.
  • No response: escalate and seek senior help:
    • Hypotensive and fluid-overloaded/cardiogenic shock: avoid extra fluid, they may need inotropes.
    • Hypotensive despite being given fluids: they may be very dehydrated (requiring more fluids) or may need vasopressors.

Manage and treat underlying causes such as:

  • Haemorrhage:
    • Use O-negative blood or arrange urgent typing (this takes around 15 minutes)
    • Massive haemorrhage – call 2222 and activate the major haemorrhage protocol – this gives packed red cells, fresh frozen plasma, platelets etc.
  • Sepsis six, use BUFALO: blood cultures, urine output monitoring, fluids, antibiotics, lactate, oxygen. 

Reassess

Reassess before moving on – has this improved?

  • If yes: move on
  • If not: get help.

Disability

Vital signs (observations)

Check relevant vital signs:

  • GCS/ACVPU score: if GCS ≤8, ≤P, or U, call an anaesthetist for intubation, use airway adjuncts, and put them in the recovery position
  • ACVPU: alert, confused, verbal effort (e.g. words/grunting), only responds to pain, unresponsive (no eye, verbal, or movement response to pain).

Examination (assessment)

Examine the pupils – are the Pupils Equal and Reactive to Light (PERL)?

  • Pupil size: pinpoint pupils could suggest opiate overdose, and dilated pupils can suggest antidepressant overdose (e.g. selective serotonin reuptake inhibitors, tricyclic antidepressants).
  • Asymmetric pupils: stroke or elevated intracranial pressure (e.g. intracranial haemorrhage)

Check tone in all four limbs and plantar reflexes.

Check drug charts and prescriptions for possible causes (e.g. opioids, sedatives etc.)

Tests

Arrange appropriate tests – think through them with the BOXES acronym:

  • Blood tests:
    • Blood glucose (DEFG – don’t ever forget glucose): usually 4 mmol/L or more)
    • Ketones: for diabetic ketoacidosis (DKA)
  • X-rays/imaging:
    • CT brain: for identifying intracranial pathology (e.g. stroke, haemorrhage etc.)

Optimisation (sort it out)

Check if they need airway adjuncts/intubation:

  • GCS ≤8, or P/U, seek urgent help from anaesthetics for intubation. Consider this even if GCS is >8.

Check if the patient is in pain and give analgesia:

  • Often morphine 10 mg in 10 mL slowly titrated for pain.

Correct glucose and/or other causes:

  • Hypoglycaemia: 50 mL of 50% glucose or 100 mL of 20% IV
  • Diabetic ketoacidosis: aggressive fluid resuscitation with 1 L 0.9% saline over the first hour and 0.1 unit/kg/hr insulin +/- added dextrose and potassium
  • Opiate overdose: IV naloxone, fast-acting (around 2 minutes), but temporary
  • Seizures: maintain airway and give benzodiazepine (e.g. IV lorazepam)

Reassess

Reassess before moving on – has this improved?

  • If yes: move on
  • If not: get help.

Exposure

Vital signs (observations)

If not already done, check the temperature.

Examination (assessment)

Fully expose the patient, cover them with a blanket, and examine from head to toe all over:

  • Rashes: may suggest meningococcal septicaemia, sepsis, allergic reactions etc.
  • Bruises, wounds, and bleeding: may suggest coagulopathy, trauma etc.
  • Infection: such as erythema, pus, swelling, crusting, warmth
  • Medical equipment: such as insulin pumps/glucose monitors, lines, catheters, drains etc.

Examine the abdomen:

  • Inspection: bruising, distention, rashes etc.
  • Palpation: for distention, swelling, organomegaly, abdominal aortic aneurysm, or peritonism
  • Auscultation: for bowel sounds
  • Consider a digital rectal examination: such as gastrointestinal bleeds, incontinence, changes in bowel habits etc.

Palpate the calves for DVT (if not done in breathing)– for swelling, erythema, or tenderness for deep vein thrombosis.

Perform a focused examination of relevant systems.

Tests

Arrange appropriate tests: such as taking samples of potential infection sources for culture.

Optimisation (sort it out)

Manage potential problems:

  • Active haemorrhage: control bleeding (e.g. applying pressure), estimate blood loss, reassess circulation, activate major haemorrhage protocol if necessary.
  • Infection: give antibiotics/sepsis six etc.
  • Hypothermia: give blankets and warm (if therapeutic cooling is not indicated) 

Reassess

Reassess before moving on – has this improved?

  • If yes: move on
  • If not: get help.

Next Steps

Short history (AMPLE)

Gather a brief history but do not delay the ABCDE assessment. This could be from the patient (if they can) or another team if needed. Use the AMPLE acronym:

  • Allergies: do they have any?
  • Medications: what do they take?
  • Past medical history: any key conditions such as heart, lung, or kidney problems?
  • Last oral intake: relevant for acute abdominal pain
  • Events leading up to now: what has happened up till now?

Overview

The ABCDE assessment is repeated until the patient is stable. If at any point there is no improvement, seek help. If appropriate, explain the working diagnosis to the patient and what will happen next.

An examiner may ask what the likely diagnosis and the next steps are. Make sure to consider and mention:

  • Working diagnosis and differentials: include justifications for these choices.
  • Getting further information: such as a history, physical examinations, vital signs trends, investigations, and their results, and review their medications.
  • Management: including next treatment steps, senior involvement, and handover using an SBAR technique.
  • Do not leave the patient: stay with them and continue reassessing.
  • Document the assessment: this can be done using the ABCDE structure.

Who to involve

Relevant contacts may include:

  • Arrest team: for cardiac arrest (e.g. no respiratory effort, no pulse)
  • Anaesthetics: for airway problems, if GCS ≤8, or P/U 
  • Major haemorrhage protocol (call 2222): for uncontrolled haemorrhage, call 2222, and activate the major haemorrhage protocol.
  • Medical registrars: in general for medical problems
  • Surgical registrars: for surgical complications and bleeding 
  • Cardiologists: for acute coronary syndrome, arrhythmia etc.
  • Gastroenterologists: for gastrointestinal bleeding, acute pancreatitis etc.
  • Endocrinologists: for endocrine problems (e.g. adrenal crisis, DKA)
  • Nephrologists: for kidney disease (e.g. acute kidney injury, nephritic/nephrotic syndrome)
  • Neurosurgeons – for intracranial haemorrhage, elevated intracranial pressure etc.
  • Neurologists: for stroke, seizures etc.
  • Gynaecologists: for pelvic pathology such as ectopic pregnancy
  • Intensive care: if higher levels of care are needed (e.g. vasopressors, inotropes etc.)
  • Dermatologists: for advice regarding skin rashes

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