The Role of Dispatch in Pattern Surveillance

After the events of September 11, 2001, dispatch centers around the world have discovered they are sitting on a goldmine of information. Originally prompted by the need to prepare for potential bioterrorism, communication center managers, EMS medical directors and public health officials have discovered that monitoring 9-1-1 data for unusual patterns also reveals trends from crimes to flu outbreaks. During last year’s fires in San Diego, 9-1-1 data were used to get an early read on respiratory problems caused by heavy smoke and became the basis for alerts from public health officials.

“One way to look at this is that 9-1-1 is the first point of entry when something untoward occurs,” says Jeff Clawson, MD, Board of Certification chair for the National Academies of Emergency Dispatch in Salt Lake City, UT. “The thing we realized is that notifications may come into different dispatch centers in the same region, or to different dispatchers in the same center, but unless there’s some way of collecting this information so we can recognize trends and patterns with increasing presence of certain conditions or symptoms, we may or may not be able to detect that something is wrong.”

Enter First Watch—a software program that can extract dispatch information out of Priority Dispatch’s ProQA software, compile it and look for trends in certain geographic areas by city, county, state or region.

“If you’re going to function in dispatch in the 21st century, you have to use computers,” says Clawson. “We’ve long fought the battle between using card versions of our dispatch protocols versus the automated versions that run as expert systems that actually obtain information as soon as it’s known and electronically share it with First Watch. They compile the information and create a standard deviation system that gives users a warning at two standard deviations above or below the mean for sentinel calls like unconsciousness, difficulty breathing, or victims who are not alert. So, if there are suddenly a bunch of unconscious patients, it might trigger a bell.

“Basically, this system is predictive, but we know what the baselines are,” Clawson adds. “We know that pretty much the same number of people on a given day or time are going to have given problems. When 25 people suddenly keel over in the subway, like they did in Japan after the sarin attack, you know something is up. But it’s not always that dramatic, especially if it’s infectious disease-related.”

The National Academies of Emergency Dispatch has added into its software program specific modules for obtaining information on CBRN (chemical, biological, radiological and nuclear), in terms of all types of symptoms, as well as a pull-down list for SARS, says Clawson.

“In the computer age, where we have the ability to update the software of FTP sites, we can add in new modules quickly,” he says. “If we get information from the CDC or NIH, we have a CBRN group in the Academy that meets immediately, even if it’s over the phone, and they can formulate a symptom pull-down menu as information changes.

“With the new awareness of terrorism, our questions have changed a bit, but we found that a lot of the questions we already used were OK for the standard sort of application,” says Clawson. “The CBRN, hazmat and SARS pull-down additional questions are very detailed, so that has definitely changed, but they’re not used on each and every call.”

Unlike CPR protocols, which are changed by the American Heart Association approximately every 5 years, using dispatch information to predict outbreaks or trends requires faster action, says Clawson.

“With this sort of thing, we have to have an on-the-fly ability to react to whatever emerges, gather the information and update it across the board for anyone who is using the dispatch protocol. With the awareness of homeland security issues, most people who know there’s an update available will obtain it.”

Clawson estimates the number of National Academies protocol users worldwide at just under 2,900, with the vast majority in the United States, Canada, England, Germany and Italy.

“It doesn’t matter where you are in the world, it uses exactly the same codes and exactly the same questions, so the data are comparable,” he says.