ABCDE approach

Last updated: March 16, 2022

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The ABCDE approach is an almost universally applicable strategy for the initial assessment and resuscitation of critically ill patients. Systems are evaluated and managed simultaneously in the order of their potential threat to the patient's survival: airway, breathing, circulation, disability, and exposure. As a first priority, airway patency is assessed and secured as needed (e.g., using basic airway maneuvers or intubation). Breathing is often evaluated concurrently and treated with respiratory support (e.g., oxygen therapy, bag-mask ventilation, mechanical ventilation) as well as specific time-sensitive therapy (e.g., bronchodilators, chest tubes). The next priority is circulatory assessment and initiation of immediate hemodynamic support (e.g., IV fluid therapy, vasopressors) as needed. A rapid neurological assessment should be prioritized next to identify reversible or time-sensitive causes of altered mental status (e.g., hypoglycemia, intracranial bleed), seizures, weakness, or other focal neurological deficits. The final priority is rapid exposure of the patient's body to identify potentially hidden clues to the underlying cause (e.g., rashes, transdermal medication patches) and remove any inciting or aggravating factors (e.g., allergens, contaminated or wet clothing). For each priority, lifesaving treatment should be initiated without delay, even if a definitive diagnosis has not been established. To ensure optimal outcomes, a team of appropriately trained staff should be assembled as early as possible, and team management should ideally follow the principles of crisis resource management (CRM). Following initial stabilization, a secondary survey including a thorough history and examination is initiated and, if necessary, the patient is prepared for transport or handed off to the appropriate specialty service.

This approach is also applicable to trauma patients with slight modifications.

Clinical applications [1][2]

  • The ABCDE approach can be applied to any situation where a quick assessment and initiation of lifesaving treatment may be necessary, e.g., in emergency departments, critical care units, wards, and prehospital environments.
  • Any potentially critically ill or unstable patient can initially be managed with this approach until they are stable enough for further diagnostics and treatment.
  • The ABCDE approach should not be used for patients in cardiac arrest.
    • If a patient is unresponsive, assess for cardiac arrest, call for help, and initiate resuscitation.
    • For further information, see “Advanced Cardiac Life Support.”

The ABCDE approach can be used for the initial assessment and management of all potentially unstable patients.

In patients with cardiac arrest, initiate CPR immediately.

Core concepts

The ABCDE approach consists of a rapid (< 10 minute) framework to assess and manage critically ill patients by prioritizing conditions with the greatest risk to their survival. [3]

ABCDE approach concepts
Goals of management Rationale for priority
  • Assess for, manage, and anticipate potential airway complications.
  • Complete airway obstruction: typically fatal within seconds to minutes
  • Ensure adequate ventilation and oxygenation.
  • Assess for and treat cardiovascular compromise, and optimize volume status.
  • Severe shock or cardiovascular collapse (excluding cardiac arrest): typically fatal within minutes to hours
  • Requires airway patency and adequate oxygenation (e.g., for tissue perfusion)
  • Variable time frames; threat to life typically slower than that of airway obstruction, respiratory failure, and shock
  • Requires patent airway and cardiorespiratory stability (e.g., for neuroprotection)
  • Fully undress the patient, screening for clues to underlying etiology.
  • Check temperature.
  • Remove inciting or aggravating items.
  • In clinical practice, assessments and interventions for each component are often undertaken simultaneously by multidisciplinary teams.
  • A definitive diagnosis or detailed history is not essential for the initiation of lifesaving treatment if there is a sufficiently high level of suspicion.
  • The ABCDE assessment is regularly repeated in order to:

Assess and treat conditions in order of the greatest potential threat to patient survival, and always anticipate potential deterioration.

Significant information on the ABCDE assessment can be gained by simply asking the patient to state their name and reason for seeking care. A coherent answer affirms momentary airway patency, the minimum ventilatory and circulatory reserves required for brain perfusion, and an adequate neurological status.

Crisis resource management (CRM) [4][5]

  • The concept of CRM outlines several strategies to improve teamwork and patient outcomes in emergency situations.
  • CRM emphasizes effective leadership, communication, and situational awareness in multidisciplinary team settings.
Principles of crisis resource management [4]
Principle Action points
Knowledge of environment and resources
  • Ensure familiarity with emergency protocols.
  • Know who and how to call for help and where to find equipment.
Thinking ahead
  • Anticipate potential problems and how to manage them.
  • Continually involve and update all team members.
Clarity of roles and leadership
  • One person coordinates the other team members.
  • If time permits, make decisions in a participative manner.
Effective communication [6]
  • Expectations and tasks should be clearly defined and assigned.
  • Practice closed-loop communication.
  • Discuss or hand off patients by summarizing SBAR.
Early activation of additional resources
  • Request urgent specialist consults as appropriate.
  • Consider the need to transfer the patient to a higher level of care.
Situational awareness
  • Avoid fixation on one particular issue.
  • Routinely announce findings, observations, and concerns. [6]
  • Consider an occasional pause to review findings and adjust the treatment plan.
Adequate distribution of tasks
  • Ensure tasks are evenly distributed amongst team members, using closed-loop communication to ensure the team leader is aware when tasks are completed.
  • Procedures may be more challenging than usual in the emergency setting and should be performed by experienced team members.

Closed-loop communication: Repeat received messages and announce the completion of tasks.

For a quick handoff, summarize SBAR: Situation, Background, Assessment, Recommendation.

Adjuncts in the assessment of critically ill patients [2][7]

Typical interventions Additional interventions to consider
  • Early specialist consults
Initial therapeutic measures
  • Two large-bore (at least 18-gauge) IV lines
  • Initial high-flow supplemental O2 for all patients
  • Nasogastric tube for decompression and assessment of gastric contents
  • Supportive treatments, such as:
Diagnostics [8]

Most critically ill patients require cardiorespiratory monitoring, IV access, and supplemental O2 as minimum initial measures during the ABCDE survey.

  • Airway and breathing are typically assessed simultaneously to identify concurrent problems and predict deterioration.
  • Airway obstruction can be partial or complete and may be caused by processes in the upper airways or a reduced level of consciousness.
  • For further information, see “Airway management.”
Airway assessment and management [2][7][8]
Component of evaluation Assessment Interim management
Inspection and auscultation
  • Patient is talking normally: Airway is (currently) patent.
  • Proceed with the survey.
  • See “Anticipation of deterioration.”
Rapid/ bedside testing and monitoring
Anticipation of deterioration

Breathing assessment and management [7][8]
Component of evaluation Assessment Interim management
Inspection General appearance
Vital signs
Specific signs

Auscultation and percussion [8]

Rapid/bedside testing and monitoring
Anticipation of deterioration

Circulation assessment and management [2][7][8]
Component of evaluation Assessment Interim management
Inspection General appearance
Vital signs
Specific signs
Auscultation and
  • Extremities: Record capillary refill and skin temperature.
  • Pulses: Assess rate, symmetry, and quality.
  • Check for abdominal tenderness.