The initial moments of any emergency response involve a structured protocol designed to maximize the chance of a positive outcome while minimizing risk to the rescuer. A systematic assessment of the environment and the patient must take place before aid is rendered. This process is founded on the principle that the rescuer’s well-being is the first priority, as an injured rescuer becomes another victim and complicates the situation.
Establishing Environmental Security
Establishing a safe environment begins the moment a rescuer approaches the scene, utilizing the principle of “Look, Listen, and Smell.” This systematic approach allows for the rapid detection of hazards that may not be immediately visible. The rescuer must actively scan the entire area for potential dangers before stepping into harm’s way.
The initial visual assessment involves looking for obvious dangers such as moving traffic, which requires securing the area, or unstable structures that could collapse unexpectedly. Downed electrical power lines present a threat, as approaching them or any object they contact can result in electrocution. A rescuer must maintain a safe distance and report these hazards immediately to professional authorities.
The sense of hearing is utilized to listen for unusual sounds, which can include hissing gas leaks, the roar of an uncontrolled fire, or shouting that may indicate violence. Simultaneously, the sense of smell can detect hazardous materials like leaking fuel, suggesting a fire or explosion risk, or strong, unfamiliar chemical odors. If a chemical or gas leak is suspected, the rescuer should move away immediately, preferably upwind, to avoid inhalation.
Personal Protective Equipment (PPE) provides defense against potential biological hazards, which is a constant consideration in patient care. Wearing gloves is a fundamental action to prevent exposure to blood and other body substances that can transmit disease. If the scene involves splashing fluids or respiratory risks, eye protection and a mask may also be necessary to protect the rescuer from infectious agents.
The assessment of safety is a dynamic process, as conditions can change rapidly even after the initial check. A safe scene can quickly become unsafe due to shifting debris, the escalation of violence, or changes in traffic flow. Rescuers must remain vigilant and continuously monitor for new threats, always maintaining an awareness of an escape route. If the scene cannot be secured, the appropriate action is to retreat and wait for specialized resources, such as law enforcement or fire services, to neutralize the threat.
Conducting the Scene Size-Up
Once environmental security is established, the Scene Size-Up commences, serving as a rapid logistical and diagnostic checkpoint before patient contact. This step involves making immediate observations that inform resource needs and guide the subsequent patient assessment. The size-up requires categorizing the incident as either a Mechanism of Injury (MOI) or a Nature of Illness (NOI).
The MOI refers to the external force or event that caused a traumatic injury, such as a motor vehicle collision, a fall from height, or a penetrating wound. Observing the MOI helps create an index of suspicion for potential internal injuries that may not be visible, like head or spinal trauma. Conversely, the NOI applies to medical emergencies where symptoms are caused by an internal condition, such as a stroke, heart attack, or diabetic episode.
Another immediate component of the size-up is estimating the total number of patients involved. This count indicates whether the available resources are adequate to manage the situation. If multiple patients are present, the rescuer must immediately consider activating additional emergency medical services (EMS) or specialized teams.
A finding of multiple people experiencing similar symptoms, such as headache, dizziness, or collapse, can signal an environmental problem like a gas leak or carbon monoxide poisoning. This observation prompts the rescuer to re-evaluate scene safety before proceeding further. Determining the need for additional resources, including fire suppression, extrication tools, or hazardous materials teams, is the final phase of the scene size-up.
Primary Survey of the Patient
The Primary Survey is the rapid, systematic examination of the patient to identify and correct immediate life-threatening conditions. This assessment begins with determining the patient’s level of responsiveness using the AVPU scale. The rescuer checks if the patient is Alert, responsive to Verbal stimuli, responsive only to Painful stimuli, or Unresponsive.
If the patient is not fully alert, the focus shifts to the Airway. An open airway is confirmed by checking if the patient is speaking clearly, as the ability to talk indicates air is moving past the vocal cords. If the patient is unresponsive, techniques such as the head-tilt/chin-lift maneuver are used to open the airway, and the mouth is inspected for foreign objects or fluid that could cause an obstruction.
Following airway management, the rescuer assesses Breathing by looking for the rise and fall of the chest, listening for air movement, and feeling for breath near the mouth and nose. This assessment should be conducted for up to 10 seconds to confirm if breathing is present and adequate. If breathing is absent or ineffective, immediate intervention, such as rescue breaths or cardiopulmonary resuscitation (CPR), must be initiated.
The final two steps involve checking Circulation and looking for external bleeding. Hemorrhage must be identified and controlled immediately, often by applying direct pressure or a tourniquet if the bleeding cannot be stopped by other means. The rescuer also quickly checks for a pulse, often at the wrist (radial) or neck (carotid), to assess the presence and quality of blood flow. The goal of this primary assessment is to find and fix any life-threatening issues before moving to a more detailed evaluation.