Statistic Case

Every year, thousands of people die of heart attacks partly because of delays in waiting for

emergency medical care to arrive. One form of heart attack is ventricular fibrillation rhythm,

which is treated by a defibrillator. However, immediate medical attention is critical. In general,

if a patient receives treatment within 8 minutes, he or she is very likely to survive. It is

estimated that the probability of survival is reduced by 7% to 10% for each minute thereafter

that defibrillation is delayed.

The region in the Ambulance and Fire Department Response Interval Study is composed of the

three cities of Cambridge, Waterloo, and Kitchener. Each city has a fire department, and the

region has a 911 emergency telephone system. When a medical-related call is received by the

Police Dispatch Centre, it is relayed to the Central Ambulance Communication Centre (CACC).

The CACC dispatches both the ambulance and the fire department to certain calls that match

one of several criteria indicating the need for fire department personnel. There are two

ambulance services that cover the region: the Cambridge Memorial Hospital Ambulance Service

and the Kitchener-Waterloo Regional Ambulance Service. Currently, ambulance personnel sent

to the patient after a 911 call perform all defibrillation. A city counselor recently suggested

that, since the fire department has more centers, it is likely that