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Paramedics at the open door of an ambulance in the foreground, with several other ambulances in the background under a red sign reading 'Emergency'
When ambulances are delayed at overcrowded hospitals because they can’t offload patients, it means they can’t respond to emergency calls and people wait longer for paramedics to arrive. THE CANADIAN PRESS/Frank Gunn

Emergency department crowding has gone beyond hallways onto ambulance ramps. Now there’s nowhere left to wait.

A hospital’s emergency department (ED) has long been considered the canary in the coal mine for the health-care system: when it’s congested, the whole hospital is congested.

Routine and prolonged ED congestion has since led to declarations that patients waiting in an ambulance outside the ED are the new canaries in the coal mine.

But when ambulances waiting outside the ED become routine and prolonged, another new canary appears: patients at home waiting for an ambulance. They may represent the truest analogy for the canary in the coal mine because they are literally dying and are a clear indicator that the health-care system is congested at a dangerous level.

Pinch points

Delayed handovers of patients arriving by ambulance is a decades-old problem challenging health-care systems around the world. In the United Kingdom, the National Health Service has made eliminating handover delays one of its three priorty reforms for pre-hospital urgent care in its 10-year Long Term Plan.

A long hallway with patients on gurneys along one wall, with a paramedic speaking to one of the patients
When emergency departments become congested, there is spillover into hallways. Further congestion means spillover onto ambulance ramps, and eventually there are no ambulances available to respond to calls. THE CANADIAN PRESS/Nathan Denette

In Canada, where health care is provided by provinces, British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Québec, New Brunswick and Nova Scotia have all experienced challenges handing over patients in a timely manner.

Australia has likewise seen long lineups of ambulances queueing at hospitals, and has committed to hiring thousands of paramedics in an effort to combat year-on-year increases in patient handover times.


Read more: Ambulance ramping is a signal the health system is floundering. Solutions need to extend beyond EDs


Beyond ambulance handovers, delays and congestion also occur at other areas: the ED, wards and long-term care are some of the pinch points common in health-care systems around the world.

As an industrial engineer researching and working in health-care patient flow, this raises the question: where’s the next pinch point?

Code zero

We know hospital congestion is routinely caused by access block, which occurs when patients are blocked from flowing through the system by a lack of downstream capacity. This is often rooted in an inability to discharge patients from the hospital, which is often due to lack of space in long-term care.

Naturally, this stalls the flow of patients, causing them to wait in ward beds to be discharged from the hospital, in ED hallways waiting for ward beds, in ambulances waiting for ED beds, and eventually at home waiting for an ambulance.

This last group represents a new pinch point. Although ambulances not meeting targeted response times is not new, it is a relatively new phenomenon that there are no ambulances available to respond to calls in a timely manner — a situation known as “code zero.”

This new pinch point however, is substantially different from the others. The patients affected have not yet been seen by health-care providers, are not within meters of health-care services, and their urgencies are not known. These patients are at home, in unknown duress, waiting.

Acute care director of the National Health Service in the U.K. discusses ambulance delays, and a family tells how delays led to tragedy.

Patients waiting with an ambulance on the “ramp” (known as “ramping”) or in a hallway between the ED and the ward are known to be at higher risk for adverse outcomes. Patients with hospital stays prolonged by delay are likewise at higher risk for hospital-borne infections and adverse outcomes.

Less is known about patients waiting at home for an ambulance, but given their precarious circumstance, it is logical to assume they are also at high risk.

Patients at risk

Many emergency services system evaluations in Australia, Canada and the U.K. have reported waiting times longer than performance targets. But the extent to which they are waiting is new.

It has become all too common to read about code zero situations, in which there are no ambulances available. Again there are reports from Australia, the U.K. and Canada. People are dying while waiting.

In Australia, ambulance ramping and call delays were recently linked to 33 deaths over 18 months.

In three examples from the U.K., a woman died following a 16-hour wait for an ambulance, a man died when no ambulance was available to take him to the hospital, and an 87-year-old died after waiting 17 hours for an ambulance and then 13 hours in the ambulance at the hospital.

In all three U.K. cases, long handover delays and ambulance ramping were identified as the cause of ambulance unavailability.

System failures spilling over

In Canada, the frequency of zero ambulances available doubled in Ottawa in 2022, with offload delays identified as the number one cause. Code zeros are reported to be daily occurrences, with prolonged frequencies and durations in Hamilton, Ont. A woman in Montréal died after waiting seven hours for an ambulance.

A “canary in the coal mine” is an early indicator of potential danger or failure. The response was insufficient when the ED’s canary died, and the failure spilled over to the ambulance service. Now, with prolonged offload delays routinely causing zero ambulances to be available, the ambulance ramping canary isn’t long for this world either.

This time when the failure spills over, the “canary” at risk is not a metaphorical bird, but is instead a patient waiting at home for an ambulance.

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