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OC Annex - MCI Leveling


The leveling of an MCI allows for the rapid deployment of resources and increased situational awareness of surrounding cities and departments.  All numbers in the leveling system are estimates and the complexity of an incident can drive an increase in the level (active shooter event with 20 gunshot victims may be designated a level 3 MCI due to the overload of our trauma system).


MCI Level (1) 3 - 9 patients (approximate) A suddenly occurring event that overwhelms the routine first response assignment. The number of patients is greater than can be handled by the usual initial response. Depending on the severity of the injuries the system may have adequate resources to respond and transport the patients. Duration of the incident is expected to be less than 1 hour. Examples: Motor vehicle accident, pepper spray event.


MCI Level (2) 10 - 29 patients (approximate) A suddenly occurring event that both overwhelms the first response assignment and, additional resources requested within the Operational Area or neighboring counties. The Regional medical mutual aid system is activated. An adequate number of additional ambulances are not likely to be immediately available, creating a delay in transporting patients. The duration of incident is expected to be greater than an hour. Examples: Bus crash, train accident, active shooter, improvised explosive device (IED).


MCI Level (3) 30 + patients (approximate) A suddenly occurring event that overwhelms the first response assignment, additional resources requested within the Operational Area, and mutual aid from neighboring counties. It is not possible to respond with an adequate number of ambulances to the incident and promptly respond to other requests for ambulance service. Regional medical mutual aid system is activated. Air and ground ambulance and other resources from outside the county are required and receiving hospitals will be overwhelmed. In an incident of this size and complexity, the operational area EOC and disaster plan may be activated. Examples: Commercial airline crash, building collapse, active shooter.  A Level (3) MCI could also deal with the complexity of the event, for example; an active shooter incident with 20 gunshot victims could be a Level (3) MCI due the complexity of the event and the overwhelming of the trauma system.


OC Annex - ICS Positions and Functions



Command of an MCI could be at different levels depending on the size and complexity of the incident.  The Incident Commander could directly command the MCI on a smaller isolated event or that function could be the responsibility of the Medical Branch Director or Medical Group Supervisor for larger more complex incidents.  Below are the basic functions of Command on an MCI:


1. Establish Command and identify the incident as a Multi-Casualty Incident (MCI).


2. Assign triage as soon as possible using the START Method of triage.


3. Estimate the number of patients, declare the Level of MCI, and report to dispatch.


  • Exact numbers or patient triage category are not required at this point.

  • Estimates like: 3-5, 4-8, 10-15, 30-50, 100 plus are adequate in the early stages. A more accurate count can be communicated when available.

  • The level of the MCI can be derived from the number of the patients and/or a combination of the number of patients and the complexity of the event.

    • An active shooter event of 10 gun-shot victims will overwhelm the nearest trauma centers, require extra resources on scene, and cooperation from multiple agencies, this could be designated a level 3 MCI.


4. Request additional resources


  • Order resources based on initial estimates. Special consideration must be given to ordering an adequate number of ALS units and ambulances.

  • Paramedic/EMT and Ambulance Resources

    • (1) Paramedic, (1) EMT, and (1) ambulance should be assigned to each Immediate patient.

    • (1) Paramedic, (1) EMT, and (1) ambulance should be assigned to each Delayed patient.

    • A minimum of (1) EMT should be assigned to each small group of Minor patients.


Note:  When paramedic resources are depleted, patients can be evaluated and transported by EMT’s and on large incidents, multiple patients can be transported in one ambulance.  

Note: Paramedics that respond on ambulance transport units should be considered treatment teams. Additional private transports should be requested if necessary.

5. Assign ICS positions


  • The IC / Medical Branch / Medical Group will assign the positions in an MCI based on the size and complexity of the incident.

  • Basic positions that should be established on each MCI are:

    • IC

    • Triage Unit Leader (Triage)

    • Medical Communications Coordinator (Med Com)

    • Patient Transportation Unit Leader (PTUL)

    • Ground Ambulance Coordinator (GAC)


Triage will be performed using the Simple Triage and Rapid Treatment (START) Triage System by the initial resources on scene (Attachment B).  When resources become available a Triage Unit Leader is established (usually the first in Captain, after being relieved by BC).  The Triage unit leader is responsible for the patient triage, treatment, and movement while in the triage area.  Below are basic functions of Triage on an MCI:


1. Inform Medical Group Supervisor/IC of resource needs.


2. Implement the triage process using START and JUMP START.

  • Triage ribbons should be used for initial triage of patients on Multi-Casualty Incidents.  This is considered the Primary Triage.  Patients triaged with ribbons will be assigned a triage tag once a treatment team is committed or before they leave the scene, this is considered Secondary Triage.

  • If appropriate resources are available, provide immediate spinal motion restriction (SMR) when dealing with potential spinal injuries.

  • Triage personnel will report the number of patients and triage category to their supervisor as soon as that information is available.


3. Coordinate movement of patients from the Triage Area to the appropriate treatment areas or directly to the transport areas (smaller incidents).


4. Ensure adequate patient decontamination and proper notifications are made.


5. Assign resources as triage personnel, litter bearers, or treatment teams.


6. Give periodic status reports to Medical Group Supervisor/IC.


The main goals of treatment on an MCI are to stabilize life-threatening injuries and prepare the patient for transport to the hospital.  Treatment can take place in the triage area if the patients have not been moved (small traffic collisions) or in an area set aside specifically for treatment (red, yellow, green tarps).  If a treatment area is established a Treatment Unit Leader should be established.  The Treatment Unit Leader is responsible for establishing Immediate, Delayed, and Minor treatment areas, and the movement of patients from the treatment area to the ambulance loading area.  Below are basic functions of Treatment on an MCI: 


1. Perform a secondary triage on all patients.


2. Place a triage tag on each patient for tracking.


3. Set up defined areas for treatment of Immediate, Delayed, and Minor patients.


4. Treat patients, stabilizing life-threatening injuries, and prepare patients for transport.


5. Assign (1) Paramedic and (1) EMT for each Immediate and Delayed patient as resources are available.  All Delayed and Immediate patients should be evaluated by a Paramedic if resources allow.


6. On large, spread out incidents with multiple treatment areas, a Patient Loading Coordinator can be utilized to prepare patients for transport and move them to the loading areas.  The Patient Loading Coordinator reports to the Treatment Unit Leader.


The transportation function in an MCI is made up of the Patient Transportation Unit Leader (PTUL), Medical Communications Coordinator (Med Com), and the Ground Ambulance Coordinator (GAC).  It is important to establish a Med Com early in the incident to ensure proper notification to the hospitals.  The Patient Transportation Unit Leader is responsible for the coordination of patient transportation and maintenance of records relating to patient identification and destination.  Below are some basic functions of Transportation on an MCI:


1. Establish communications with OCC / Base Hospital through a single Med Com.


2. Identify the Receiving Centers for each patient leaving the scene, utilizing: OCC, the Base Hospital, or the Patient Care Capacity Inventory established by OCEMS.  Tracking of all patients leaving the scene is critical for the overall incident.


Establish a clear path for ambulance ingress and egress.


The Medical Communications Coordinator (Med Com) is responsible for maintaining communications with the Base hospital to assure appropriate patient destinations. Med Com reports to the Patient Transportation Unit Leader.  It is important to start this process of determining patient destinations early, it takes the Base Hospital a few minutes to identify the closest receiving centers, specialty centers, and the number of patients each can take.


It is important to note, there should only be one Medical Communications Coordinator on an MCI, regardless of the size, complexity, or geography.  This will prevent the overloading of hospitals where possible.  If additional patient treatment or loading areas are necessary (spread out incident), a Patient Transportation Unit Leader can be established at remote locations and destinations will be received from Med Com on a medical tactical frequency.  The following are basic functions of Med Com:


1. Consider establishing a position forward of Ambulance Loading.  Med Com should not be a mobile position, establish a position near the patient loading area.


2. Contact OCC on 6 Alpha & ID themselves as “(incident name) Med Com” and request a frequency.


3. Provide incident description, estimated number of patients, and level of MCI.


4. Give Patient Report based on level of MCI, reporting should be limited to pertinent information and only if available.


5. On level 3 MCIs, if the Base becomes overwhelmed, OCC may relay destinations directly to Medical Communications or assist the Base Hospital.


6. Relay hospital destinations to Paramedic/EMT treatment teams directly or through the Patient Transportation Unit Leader.


7. For large or spread out incidents a medical tactical frequency should be requested and utilized to coordinate destination needs between Patient Transportation Unit Leader(s) and Med Com. 


8. In the event of communications failure, destinations will be determined per OCEMS’s Patient Care Capacity Inventory (PCCI), or utilizing ReddiNet through dispatch centers.


Level (1) Radio Report

– Triage Tag #                                                

– Patient age

– Major injuries                                              

– Patient gender

– Ambulance identifier                                  

– Vitals

– A destination or specialty request              

– Patient category (Immediate, Delayed, Minor)

– Need of a Trauma center (priority given to the most severe traumas first)


Level (2) Radio Report

  • Triage Tag #

  • Patient category (Immediate, Delayed, Minor)

  • A destination or specialty request

  • Ambulance identifier

  • Additional information when available


Level (3) Radio Report

  • On large or complex incidents, little to no information will be given to the base hospital or receiving center.  The Base will monitor ReddiNet and be ready to assist Med Com with the distribution of patients.

  • If time and resources allow, give Level #2 report.

MCI Levelin
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