North Shore hospitals are no longer closing their emergency rooms to ambulances during busy periods, a practice that was unpopular with first responders, who faced longer drives, and Cape Ann residents, who said it weakened Addison Gilbert Hospital.

The change in policy, ending the practice known as ambulance diversion, is being imposed on all Massachusetts hospitals by the state, which has been trying to get them to process emergency room patients more efficiently.

Starting the first of the year, hospitals will not be allowed to close their emergency rooms to ambulances to prevent overcrowding unless they are facing an internal disaster, such as a fire.

Hospitals will still be able to send patients to other facilities for more specialized care. Emergency rooms cannot divert patients who arrive at the hospital by means other than ambulance.

But even before the new rules go into effect, area hospitals have almost entirely ceased diverting emergency room patients.

During the first two weeks of December, the 14 hospital emergency rooms in Massachusetts' Northeast Region were closed to ambulances for a total of two hours, compared with a total of 75 hours during the same time period last year, according to Jonathan Epstein, executive director of the Emergency Medical Council Region III.

Hospitals in this area have had to be ahead of the rest of the state, because the Region III council has been tightening the rules on diversion for much of the year. In July it instituted a four-hour-per day maximum diversion for each hospital.

Diversion has been a sensitive subject on Cape Ann since the sale of Addison Gilbert Hospital in 1996 to Northeast Health System, the parent company of Beverly Hospital.

As the number of local ambulance trips to Beverly began increasing, many residents feared it was a result of extensive cuts in resources at Addison Gilbert and a sign that the local hospital could be in jeopardy.

Northeast Health System declined for months to provide diversion rates or hour totals for Addison Gilbert and only this summer acknowledged that emergency room closures at the hospital had increased.

According to figures released by the state Department of Public Health in October, the number of hours Addison Gilbert was on diversion were negligible early in the decade and began rising significantly in 2006 and 2007. This year had the highest total hours on diversion at the hospital, despite the numbers diving dramatically after the state restrictions were announced in the summer.

In 2005 Addison Gilbert's emergency room was on diversion for five hours, in 2006 it was in diversion for 27 hours, in 2007 it diverted for 71 hours and in the first 10 months of this year diverted for 79 hours. The highest single month of diversion at AGH was October 2007, which had 22 hours of emergency room closure.

Beverly Hospital also showed large diversion increases between 2004 and 2007, and the total numbers, like patient volume, were much larger at the bigger hospital. Beverly was in diversion for 245 hours in 2007.

The spike in diversion in 2007 mirrored regional trends. Salem Hospital was in diversion for 528 hours in 2007.

Epstein, the regional emergency director, said yesterday that by eliminating the option to divert patients, hospitals will be compelled to streamline the triage and treatment of emergency room patients and speed the process by which patients are either admitted to the hospital or released.

"Hospitals in the North Shore have focused on overcrowding and through-put by moving patients from ER into controlled-bed space," Epstein said. "Our focus is getting (patients) upstairs where nurse-patient ratio is better and care is more specialized."

Another benefit cited by the state to ending diversion is freeing ambulances from having to take long drives to more distant hospitals that take them out of service for other calls.

With diverting patents no longer a possibility for overcrowded emergency rooms, some have expressed concern that wait times in emergency rooms will increase, something that Epstein said the state will be monitoring closely.

He said examples of steps hospitals had taken to deal with crowding while not going on diversion include having administrators focus on expediting patient care, having doctors involved in triage and having committee meetings every day to discuss patient flow.

Northeast Health System declined to grant an interview on changes resulting from the end of ambulance diversion, but in a prepared statement said Addison Gilbert Hospital had invested in new cardiac monitoring equipment and developed a "Surge Capacity Protocol" to speed the flow of patients through the emergency room.

"Expediting patient flow and throughput in the Emergency Department safely and effectively is a constant focus at Addison Gilbert Hospital," the statement said. "We recurrently evaluate our policies and procedures to determine how we may be able to continue to deliver high-quality healthcare to our patients in a more efficient manner."

Sen. Bruce Tarr, R-Gloucester, who has been closely involved in discussions about the future of Addison Gilbert, said yesterday that the end of ambulance diversion was a positive step.

"I think it is definitely a good thing," Tarr said. "It will make hospitals work harder to triage and process patients through departments. That will take extra effort, but the result for patients will be good."

But he said patients being transported away from Addison Gilbert because of a lack of specialized services at the hospital was still an issue.

Peggy O'Malley of Partners for Addison Gilbert Hospital was less enthusiastic about the change, saying it would likely only provide "marginal" benefit for Cape Ann.

She said the real diversion issues at Addison Gilbert are a result of a lack of doctors, nurses, surgeons and in-patient beds, more so than the size of the emergency room.

Epstein said he hoped eliminating ambulance diversion would help stop some patients with medical emergencies from taking themselves to the hospital instead of calling an ambulance because they feared being shipped out of town.

"We want people to use the EMS system and use 911 appropriately," Epstein said. "We still have about 5 out of 6 check-in cardiac patients by car. If someone is having heart attack they should not be fearful of not going to the right hospital."