When Deputy Fire Chief Anthony Sneidar arrived at the scene of the fatal Amtrak derailment last year, he was blocked by a swarm of police vehicles.

It had been 15 minutes since Train 188 had crashed rounding the Frankford Curve in the city's Port Richmond section. Despite the live wires on the tracks, Philadelphia police officers were extricating the wounded from the wreckage.

Sneidar was there to bring order to the chaos by seeing that victims were rapidly assessed and taken by ambulance to the right trauma center for their needs.

But the narrow, one-way streets were so choked with police cars that Sneidar's ambulance crews and medics couldn't get close, he later told the National Transportation Safety Board.

"Look, you've got to move them cars," Sneidar told the NTSB that he had pleaded over the radio to police. "They're just killing us here."

Officials say there is no evidence the logjam harmed patients beyond injuries they suffered in the crash. But the city will adopt a revised mass-casualty plan next week to ensure that responses to any future disasters go more smoothly, said Samantha Phillips, director of Philadelphia's Office of Emergency Management.

Among its guidelines: Police will be restricted from taking victims of such large-scale disasters to hospitals by themselves.

The May 12, 2015, derailment killed eight people and injured scores more.

Of the 43 Amtrak passengers who were found to be seriously injured, only three were transported to trauma centers by ambulance, according to an NTSB report. One died on arrival at Temple University Hospital.

The Fire Department and EMS carried an additional 21 victims to area hospitals for treatment, according to the NTSB.

In interviews with the NTSB in June, Fire Department officials complained that police ignored their requests to bring injured passengers to a staging area to be triaged. Their concern: People with certain injuries need to be handled with extra care, or to be treated en route by trained paramedics. Plus, they wanted to spread the burden across the city's hospitals so none would be overloaded.

"They didn't listen to me," Sneidar told the NTSB. "They kept going right into the street."

Philadelphia police rushed the majority of the injured Amtrak passengers to hospitals in the backseats of their cruisers, police vans, and patrol wagons. As a result, some hospitals were overwhelmed with wounded passengers while others received few or none.

Police officials defended their officers' actions, saying speed was the paramount concern that night.

"I would hate to think how it would have been if our cops waited for a triage operation," said a Police Department spokesman, Lt. John Stanford, who added that the new guidelines might be resisted by the rank and file.

"When you see individuals screaming for help in wreckage like that, your first instinct is to start helping," said Stanford. "Our number-one priority was to get people the treatment they needed."

SEPTA buses ferried scores of the walking wounded, dropping off dozens of new patients - some with compound fractures and collapsed lungs - at emergency departments with no advance warning, according to physicians on duty that night at Aria Health-Frankford Campus and Thomas Jefferson University Hospital.

In the days following the crash, hospital workers talked about having to triage patients once they arrived. Temple staffers, whose ER was already full when the accident occurred, set up a triage site outside the ER entrance in a newly expanded ambulance bay where they color-coded patients by condition.

The closest hospital to the crash site, Aria's Frankford campus, didn't have a trauma center but received 15 of the injured.  Nurses conducted impromptu triage in hospital's parking lot before dispatching patients to radiology for x-rays and CAT scans.

"There's no suggestion that the injuries were made worse (by police actions)," Phillips said. "We just could have done a better job and had a better alignment of resources."

How he got to the trauma center wasn't an issue for passenger Daniel Amryn, 43, who crawled from the wreckage with four broken ribs and torn ligaments in his left knee.

"I was rushed to the hospital via patrol wagon" with four other people, said Amryn, the CEO of NewBreed Advertising. "And thank God, because I was in massive pain and couldn't have waited any longer."

Philadelphia is one of the few cities where police take stabbing and shooting victims to hospitals. The practice, called "scoop and run," has been credited with dramatically lowering the city's homicide rate.

According to a 2014 study, when city police transported shooting victims, the survival rate was slightly better than when the gravely wounded were taken by ambulance.

But that doesn't mean police should do the same in a situation such as a train derailment, said the study's primary author, Roger A. Band, a physician in the department of emergency medicine at Jefferson.

"Our study only looked at patients who had penetrating trauma, gunshot wounds, or stab wounds in an urban setting, which is very different from patients who have sustained blunt traumatic injuries," Band said.

Blunt trauma may include injuries to head, neck, and spine. Without proper training and equipment, moving a victim with those injuries can exacerbate nerve damage and risk paralysis, said Gerald Wydro, chairman of emergency medicine at Aria Health.

Among the survivors, the NTSB recorded only one moderately severe head injury and one cervical spine injury. Twenty-four passengers were treated for "significant" chest injuries.

"I think the Police Department did a heroic job. They went on their instincts and did what they've been trained to do," said Wydro, who was working at Aria Frankford the night of the disaster. "But if they had added on the triage layer, it would have been even better."

Amryn, who continues to recover from the crash, said he was "eternally grateful" for the quick action by police.

"I was just happy to get out of there," Amryn said. "You can't remove the room for police to improvise.

"My vote would be to never do anything different."