· The Medical Priority Dispatch System (MPDS) is a tool that helps Ambulance Communications Officers prioritize medical 9-1-1 calls, not calls for police or fire. It helps identify which calls require the most urgent response based on the patient's condition at the time of the call. If the condition changes, the call can be reassessed. In Lambton County, MPDS supports the goal of getting the right care to the right patient at the right time.
Emergency Dispatch Updates
Ambulance Communications Officers who support Lambton County EMS are implementing a new system for prioritizing medical 9-1-1 calls. The change applies to medical calls only, not calls for police or fire. It will help ensure patients with the most serious medical conditions receive the fastest emergency response.
The Medical Priority Dispatch System (MPDS) helps Ambulance Communications Officers assess medical emergencies based on urgency and determine the most appropriate response.
The system supports effective use of emergency medical resources while helping ensure life-threatening emergencies receive priority attention.
MPDS is part of the Ministry of Health and Central Ambulance Communications Centre's transition to a standardized medical-call prioritization process across Ontario.
What stays the same: Reliable ambulance response
When you call 9-1-1 for a medical emergency, an Ambulance Communications Officer will be there to take your call.
Calls involving life-threatening emergencies, such as cardiac arrest, difficulty breathing, stroke symptoms, severe allergic reactions or unconsciousness, will continue to receive the highest priority response, as they do now.
What's changing
· Additional questions when making a call. When you call 9-1-1 for a medical emergency, you may be asked a few more questions. These questions help dispatchers understand what is happening, how serious the condition may be, and what response is most appropriate.
· Wait times for less urgent conditions. Lambton County EMS will continue to respond to non-life-threatening medical calls. During periods of high demand, patients with less urgent conditions may wait longer while paramedics respond to life-threatening emergencies. Dispatchers will continue to monitor calls, and priorities can change if a patient's condition worsens.
· Support while help is on the way. Dispatchers may provide instructions over the phone while paramedics are on the way, such as guidance for CPR, choking, or other urgent medical situations. During longer waits, callers may also receive a call back to check on the patient's status.
How this improves emergency medical care
The new Medical Priority Dispatch System will help Lambton County EMS continue to meet the emergency medical needs of our community by:
- prioritizing the most critical emergencies;
- supporting effective response coordination;
- helping determine the most appropriate emergency response;
- supporting appropriate use of lights-and-sirens responses to improve safety for paramedics and the public; and
- providing a consistent medical call assessment process.
Frequently Asked Questions
What is the Medical Priority Dispatch System?
What will happen when I call 911 for an ambulance?
· Ambulance Communications Officers will continue to be ready to take your call and coordinate emergency medical assistance. For a medical emergency, you may be asked a few more questions to help the dispatcher understand how urgent or serious the patient's condition may be. Resources may be assigned while the dispatcher continues gathering important information. You may also receive a call back during longer waits to check on the patient's status. Life-threatening emergencies, including situations such as cardiac arrest, difficulty breathing, stroke symptoms, severe allergic reactions, or unconsciousness, will continue to receive the highest priority response. Please stay on the line and answer each question as clearly as you can.
Will less urgent calls still receive a response?
· Yes. Lambton County EMS will continue responding to non-life-threatening medical calls. During periods of high demand, response times may be longer for less urgent calls while paramedics are attending to more critical emergencies. Dispatchers will continue to monitor delayed calls, including by calling back to check on a patient's condition when appropriate. Paramedics already on the way to a lower-priority call may be redirected to a higher-priority, life-threatening emergency if needed.
What if my condition worsens while I’m waiting for an ambulance?
· If a patient's condition changes while waiting for paramedics, tell the dispatcher when they call back or call 9-1-1 again if the situation becomes more serious. Medical calls can be reassessed and reprioritized as needed. The system is designed to help ensure the most seriously ill and injured patients receive priority emergency response.
Where else can I get care if my situation is urgent but not an emergency?
- For non-emergency health advice, call Health811 or visit Health811.Ontario.ca
- For community and social services, call 211 or visit 211Ontario.ca
- Contact your primary care provider, speak with a pharmacist, or visit a local walk-in clinic if one is available
- For local services and supports, visit Age-Friendly Sarnia-Lambton.
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