No Increase in LOS After Ambulance Diversion Ban

When Massachusetts imposed its first-in-the-nation statewide ban on ambulance diversions on Jan. 1, 2009 some providers voiced concerns that the policy would lead to longer emergency department wait times and delayed ambulance turnarounds.

A study shows that those concerns have not materialized.

In fact, the average ED wait time and ambulance turnaround dropped in the nine Boston-area hospitals whose records were reviewed in the study, which appeared this month in the online version of Annals of Emergency Medicine.

Researchers examined ED records for all of 2008, the year before the ban was imposed, and for 2009, using length of stay as the measure for crowding. The data showed that none of the nine hospitals' EDs saw an increase in length of stay for admitted or discharged patients, and there was no increase in ambulance turnaround time, despite an increase in overall ED patient traffic.

Overall, ED volume at the nine hospitals increased by 3.6% after the diversion ban but length of stay fell 10.4 minutes for admitted patients and ambulance turnaround time fell 2.2 minutes, the study found.

"For us, the key point was that times went down at all. We had heard that things were going relatively well but we wanted to approach it quantitatively," says study coauthor Laura G. Burke, MD, MPH, an emergency physician with Beth Israel Deaconess Medical Center in Boston.

"We actually were surprised we found some decreases. The key take home is that it didn't cause disaster. Considering how frequently hospitals in our state and across the country have used diversion, that is an important finding that we eliminated it across the board and things went well."

Not only did the study alleviate fears about ED backlogs, Burke says the results also undermine arguments that diversion is an effective strategy for combating overcrowding.

"There were concerns when the ban was imposed that diversion had been the way of doing business for some time and it was a significant policy change so there were definite concerns that it would cause problems for hospitals," Burke says.

"But there has been research in emergency medicine that has looked at what are the main causes of ED crowding. The thought is that it is output factors that lead to ED crowding, predominantly boarding of admitted patients in the ED. If you want to impact crowding, ambulance diversion isn't the best way to go about it. Hospital-wide factors such as lack of bed availability or insufficient staffing cause boarding in the ED, which is a much greater contributor to crowding."

In addition, Burke says, diversion causes problems for patients and hospitals.

"If you are followed primarily at one hospital and forced to go to another hospital that causes problems for patients. When one hospital is on diversion it causes problems for other hospitals," she says.

Diversion planning also forces hospitals to construct overly complicated Rube Goldberg-type contraptions designed for a strategy that doesn't work. "I talked to people who have been involved in diversion for a long time and they talked about this whole infrastructure created for diversion and when to go on diversion but it really doesn't solve the problem of crowding and it creates a lot of problems," Burke says.

Massachusetts imposed the ban on ambulance diversions after a decade-long study determined that "diversion has been shown to be ineffectual in addressing ED overcrowding, and its elimination is in the best interest of patient safety." Bay State hospitals are prohibited from diverting ambulances unless the ED is on "Code Black" status for contamination, fire, flooding, or other disasters that limit operations.

"Massachusetts hospitals have led and continue to lead the nation in finding ways to reduce ambulance diversion," says Anuj Goel, the Massachusetts Hospital Association's vice president of legal and regulatory affairs.

"In 2009, we were the first state to restrict the use of ambulance diversion by developing a collaborative environment for hospitals, physicians, ambulance companies and state regulatory agencies to find ways to address administrative and regulatory barriers to this effort. Today, we've moved beyond ambulance diversion to focus on patient flow for care provided before and after emergency department visits, to assist patients in our communities receive both timely and effective medically necessary care."

Burke says the announcement of the diversion ban in June, 2008 forced hospitals to abandon a flawed strategy to address ED crowding and look at the problem from a new direction in the months before the ban was imposed.

"Several hospitals took that six months before the implementation of the ban to make some changes," she says. "We asked people informally what they did to prepare for the ban. There were all sorts of things to improve flow. Now hospitals have made these changes to improve patient flow and that led to decreases in patient crowding."

While pleased with the study's findings, Burke concedes it has "limitations" that might gloss over some wait time issues.

"We looked at medium monthly length of stay so there could be smaller isolated periods of crowding that our study doesn't take into account," she says. "We are not trying to say that the ban is going to cause your crowding to go down but in our study sample it didn't cause an increase in crowding."