In Fall 2026 Perth County Paramedic Services and the London Central Ambulance Communications Centre (CACC) will introduce the Medical Priority Dispatch System (MPDS) for all medical 911 calls in Perth County.
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What is the Medical Priority Dispatch System (MPDS)?
MPDS is a structured, medically approved system that helps Emergency Medical Dispatchers quickly identify the urgency of a call. By asking a specific list of more detailed questions, dispatchers can prioritize patients based on their needs and send the right resources to the right patients at the right time.
This modernized evidence-based system is designed to help Paramedics reach the most critically ill patients as quickly as possible. The system also includes quality assurance measures to ensure patients continue to receive the highest standard of care, while those who can safely wait, do so without risk.
MPDS is already used in ambulance communication centres across over 52 countries, including in Canada.
Why is MPDS being Implemented in Perth County?
The expansion of the Medical Priority Dispatch System is part of the Ontario Government’s Your Health Plan, to ensure that paramedic services provide the right care at the right time, while easing pressures on emergency departments.
Previously, Central Ambulance Communications Centres (CACC) in the province relied on a dispatching protocol known as Dispatch Priority Card Index. With this protocol, low priority calls for ambulance services were often over-prioritized, which could deplete communities of valuable paramedic resources.
The Medical Priority Dispatch System is designed to help Emergency Medical Dispatchers understand a patient’s level of urgency and triage them accordingly. The system allows Central Ambulance Communication Centres to match available paramedic resources with a patient’s condition, ensuring that the right paramedic resources are appropriately dispatched and patients with life-threatening conditions receive care immediately. The system optimizes paramedic resources, prioritizes the most urgent 911 calls, and ensures the right care at the right time for people.
How does MPDS work?
The Medical Priority Dispatch System is a specialized tool used by Emergency Medical Dispatchers to assess 911 medical calls and determine which require the fastest response. It uses a structured, evidence-based approach to triage emergencies based on severity, ensuring that patients in the most critical condition receive care first. Using MPDS, Emergency Medical Dispatchers can quickly identify:
- Life-threatening emergencies – such as cardiac arrest, severe breathing issues, allergic reactions, or unconsciousness
- Serious but stable conditions – urgent, but not immediately life-threatening
- Minor injuries or illnesses – that can safely wait for care
Built on decades of medical research and best practices, MPDS helps ensure that dispatch decisions are consistent, informed, and tailored to each patient’s needs. The goal of MPDS is to send the right resource to the right patient at the right time. While previous systems would dispatch ambulances on a first-come, first-served basis, this system supports a more clinically-driven approach.
What to Expect When You Call 911
When you call 911 for a medical emergency, you will notice that the Emergency Medical Dispatchers ask more detailed, scripted questions. This is not intended to delay the response time but will provide Paramedics with vital information before they arrive and help the dispatcher provide you with immediate assistance over the phone. You may notice some important changes:
- More detailed questions – Emergency Medical Dispatchers will ask additional questions about the patient’s condition and exact location, especially in life-threatening emergencies such as cardiac arrest, stroke symptoms, severe bleeding, trauma, or loss of consciousness.
- Paramedics dispatched right away - Even while you are still answering questions, Paramedics will already be on the way to you.
- Prioritized response times - If the situation is not life-threatening, you may experience longer wait times so that Paramedics remain available for those who need immediate critical care.
- Ongoing support from dispatchers – Emergency Medical Dispatchers undergo extensive training with MPDS and will stay in contact with you, providing support and instructions until help arrives.
Important: Answering questions does not delay help. In fact, the more details you provide, the faster and more accurately the right resources can be dispatched.
Why this change matters
The goal of MPDS is to save more lives and make sure patients receive the right care, at the right time. By prioritizing calls based on urgency, MPDS will:
- Ensure faster care for patients in life-threatening situations.
- Keep paramedics more available for emergencies.
- Safely manage non-urgent calls without taking resources away from critical needs.
- Support dispatchers with a proven, structured system used worldwide.
- Give the most urgent calls top priority, resulting in better outcomes for patients.
- Reduce the risk of under-prioritizing calls, resulting in better outcomes for patients.
- Reduce the need for Paramedics to drive with lights-and-sirens, improving paramedic and public safety by reducing the risk of traffic-related accidents.
- Ensure the best use of resources.
If you wait a while for the ambulance to arrive
You waited because there were others in your community who were more critically sick or injured than you.
If you’re having a heart attack, stroke, or other life-threatening emergency, you will receive help within minutes. If you’re having an urgent but not life-threatening emergency, you may wait longer for paramedics to arrive if paramedics are busy with other patients, or someone else calls 911 who needs immediate care.
For example, if you’ve broken your ankle, and someone else is having difficulty breathing, the next available paramedic will be sent to the person struggling for air.
This doesn’t mean your call is not important. We know how stressful it can be waiting for Paramedics to arrive. It’s difficult being sick or watching a loved one in pain. Rest assured, Paramedics will get to you as quickly as possible. They want nothing more than to help you in your time of need.
Our Commitment to the Community
Our dedication to serve the community has not changed. If you call 911, Perth County Paramedics will be there. The difference with MPDS is that life-threatening emergencies will get immediate priority, while less urgent situations may wait a little longer. Your safety continues to be our top priority.
