Managing patients requires approaching their care systematically. During cardiac arrest, the responder’s goal is to ensure adequate circulation, ventilation, and oxygenation to cause a return of spontaneous circulation (ROSC). 

This management is based on findings from: 

• The Initial Impression of the scene and patient
• The BLS Assessment 
• The Primary Assessment (A, B, C, D, E)
• The Secondary Assessment (SAMPLE, Hs and Ts)

Box 1: Initial Impression

As the provider approaches the patient, it is important to assess the safety of the scene and visually inspect the person.

Box 2: Unconscious Patient

As the provider talks to the person and shakes their shoulder, do the patient’s eyes open? If not, this indicates a BLS assessment is required.

Box 3: BLS Assessment

If the person is unconscious, it is important to conduct the BLS assessment and provide the appropriate basic life support interventions. This assessment determines the need for CPR and defibrillation by assessing circulation, airway, and breathing (C-A-B). If the provider stimulates the patient and the patient awakens, they can proceed to Box 5.

Box 4: Conscious Patient

If the patient is conscious, the rescuer proceeds to Box 5.

Box 5: Primary Assessment

If the patient revives or is conscious, the provider conducts the primary assessment. This assessment uses the A-B-C-D-E mnemonic: airway, breathing, circulation, disability, and exposure. If the patient becomes unresponsive at any time, the rescuer goes to Box 3 and conducts a BLS assessment.

Box 6: Secondary Assessment

Upon completing the primary assessment, the provider conducts a secondary assessment, which involves obtaining a focused history. This can be aided by using the SAMPLE mnemonic: 

• Signs and symptoms
• Allergies
• Medications, including the last dose of each medication
• Past medical and family history
• Last meal consumed
• Events and circumstances

The first step is to determine the safety of the scene and the patient’s level of consciousness. 

• Unconscious patients are evaluated by BLS first, and then the primary and secondary assessments are done for a more thorough appraisal of the situation.
• Conscious patients are evaluated first by the primary assessment.

These three areas: BLS, primary, and secondary assessments, can be used to systematically evaluate and manage emergent situations. They can be modified to manage a patient with common or uncommon health conditions such as lightning injury, trauma, or drowning.