EMT · Scene Size-Up and Safety · 6 min read
Patient Count, Resource Requests and Multiple-Casualty Incidents
- Identify scene indicators to accurately determine patient counts and recognize when patient-care needs exceed available resources.
- Explain when and how to request specialized resources, advanced life support, and law enforcement while maintaining scene safety.
- Describe the structure of the Incident Command System and apply the START triage system during a multiple-casualty incident.
Determining Patient Count During Scene Size-Up
Determining the total number of patients begins during the scene size-up before making patient contact. Getting an accurate count early shapes the entire emergency response. When it is safe to do so, performing a 360-degree survey of a vehicle crash scene helps identify additional patients and potential hazards that might otherwise remain hidden from view.
Specific clues on scene can alert you to missing or unspotted occupants. The presence of child safety seats in a vehicle indicates the potential for infant or pediatric patients who may have been thrown or removed. Multiple used seatbelts or other signs of occupancy may suggest additional occupants were inside. However, deployed airbags alone do not establish how many people were in the vehicle, as multiple bags can deploy for a single occupant. An ejected occupant strongly suggests a high-energy mechanism; when safe, look for additional victims beyond the immediate crash site.
Never overlook the information available from people already at the scene. Alert and responsive patients should be asked directly how many people were traveling or present with them. Verifying this number early prevents crews from leaving a scene before every patient has been discovered and cared for.
Common mistakes
- Assuming that an incident is defined as an MCI solely because a unit is low on supplies, forgetting that patient-care needs must exceed available response capacity.
- Abandoning Incident Command responsibilities to provide direct clinical care to a severely injured patient.
- Conducting a comprehensive, detailed physical exam on the first patient encountered rather than START primary triage, which generally takes 30 seconds or less per patient.
- Entering hazardous environments like unprotected trenches, confined spaces, or moving water without specialized rescue training and equipment.
Key points
- Patient counting begins during scene size-up; use a 360-degree survey, occupancy clues like child seats, and patient statements to find all victims.
- Request additional transport units, ALS, fire, or law enforcement immediately once the need is recognized so care does not delay resource arrival.
- EMTs without appropriate training and protective equipment must stay out of technical-rescue hazard zones and hazardous-materials hot or warm zones, and remain safely clear of downed power lines; they may provide BLS care in a designated safe area.
- An MCI occurs when patient-care needs exceed available response capacity; if command has not been established, the first arriving EMT may establish it and must maintain or formally transfer command before taking on patient care.
- Incident Command uses plain language, limits span of control, and designates staging and transport officers to control vehicle flow and hospital distribution.
- START triage evaluates walking capability, respirations, perfusion, and mental status, limiting immediate care to airway opening and severe bleeding control.
- Adult START assigns Red (Immediate), Yellow (Delayed), Green (Minimal), or Black (Deceased, for a patient who remains apneic after airway opening); reassess patients as conditions change.
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Sample lesson: Scene Safety, Standard Precautions and PPE Selection25 practice questions on this exam
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