For too long, Charleston County's emergency workers put tradition before logic.
Any time EMS deployed two ambulances, it set up another at Aviation and Rivers avenues, ready to head out to the next call. That positioning didn't have anything to do with historical data or traffic patterns or even a good spot where paramedics could hang out while waiting for calls.
"We went there because we'd always gone there," said EMS director Don Lundy.
After decades of working that way, the procedure changed about a year ago, when the county agency started using information collected every day on its ambulances to station its personnel and equipment in places identified as the most needy. The result: A countywide response time that dropped from an average of 10 minutes and 15 seconds to 8 minutes and 21 seconds.
Lundy said the improvement in response time came overnight, to the point that he kept saying, "Let's wait for next month" before bragging about the faster times. But the trend held.
Charleston County's ambulances use a computer program that employs GPS mapping in real time. The program also records information along
its routes, including traffic patterns and the concentration of calls on particular days at particular times of the year.
The technology creates a virtual map of calls that haven't happened yet, color-coded much like a storm-tracking weather map to show the likelihood of a medical emergency. Lundy said the system takes into account social events, such as major shopping days that bring people to malls and football games that shift the population toward stadiums.
Those in the public safety industry call the effect "dynamic deployment."
As Lundy explains it, the county's emergency medical need "changes every five minutes or every five miles."
The farthest reaches of the county -- Edisto Island and McClellanville -- pose a unique set of challenges to keeping response times low. A trip to a hospital in downtown Charleston could take an hour and could take an ambulance 40 miles away from its station. Lundy said such a call can put a rural ambulance out of commission for other calls for two or three hours.
In recent weeks, EMS officials launched a new procedure that puts a supervisor in a sport utility vehicle stocked with medical equipment at the rural outposts between 8 a.m. and 6 p.m. An ambulance is then stationed away from that remote point and closer to more populated areas.
EMS Maj. Chuck Millican said the new plan amounts to four hours of additional paramedic coverage county-wide. He predicts a 20 percent to 30 percent increase in ability to respond to calls.
The only drawback is that the SUV lacks a stretcher and can only stabilize and treat a patient. The supervisor still must wait for an ambulance or, in severe cases, a helicopter to take a patient to a hospital.
Charleston County Councilman Dickie Schweers, who represents McClellanville, hadn't heard about the service shift but said it makes sense to put resources closer to the tax base.
"You really cannot expect the same level of service in a rural area that you get in an urban area," Schweers said. "If this is based on actual calls and if they are improving service to areas where service calls typically come from, that could be a good thing. It's not like they're neglecting the rural areas completely. They're just serving the need."
Charleston County EMS serves about 315,000 people, and calls climbed 6 percent this year, Lundy said. He attributes the jump to tourism from Southwest Airlines' new service and Carnival Cruise Lines making Charleston a home port, plus growing businesses such as Boeing.
Lundy said the new plan should serve more people, because the population shifts toward more populous areas of town during work hours and back toward suburbs between evening and early morning.
"People want an ambulance outside their homes, but I really want EMTs in the whole county, because I could be anywhere," Lundy said.
The new plan, rolled out in mid-November, exists on a trial basis while county officials assess its progress. Lundy said the change in deployment comes without a change in cost or personnel.
"It's all about the sick guy," Lundy said. "We want to get to the sick person quickly with the help that he needs, with the resources that we have."
Reach Allyson Bird at 937-5594 or Twitter.com/allyson jbird.