A veteran with diabetes and poor circulation checked into the Memphis VA Medical Center for a scan and possible repair of blood vessels in his right leg last year, but what he left with was a piece of plastic packaging that VA providers had mistakenly embedded in an artery.

Doctors didn’t discover the 10 inches of tubing — used by manufacturers to protect catheters during shipping and handling — until the veteran had to have the leg amputated three weeks later.

When they cut into his leg, they found a 3-inch segment, and after the procedure, they found another 7 inches in the amputated limb.

The error is one of a litany of patient safety issues at the Memphis hospital in recent years chronicled in a trove of internal documents obtained by the USA TODAY NETWORK that provide a revealing glimpse of one of the most troubled VA hospitals in the country.

The hospital is one of only four across the country on which the VA's top health official, Acting Under Secretary for Health Poonam Alaigh, requested weekly briefings, according to the documents.

The Memphis VA facility received one out of five stars in the agency’s internal quality-of-care rankings and the documents show reports of threats to patient safety at the hospital soared to more than 1,000 in 2016, up from 700 the year before.

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Among the serious incidents investigated in 2016: The medical center mishandled a tissue sample resulting in a repeat biopsy, a provider perforated a patient’s colon during a colonoscopy, and a patient with abdominal pain and blood in his urine waited two hours in the emergency room before leaving for another local hospital where the patient “was deemed urgent and seen immediately.”

As a result of the ongoing problems and heightened scrutiny, the Memphis hospital’s new director is undertaking sweeping personnel changes aimed at improving quality, and the House Veterans Affairs Committee is investigating the safety lapses.

U.S. Rep. Phil Roe, R-Tenn., the committee's chairman, said he is "outraged" by the ongoing issues at the hospital.

“I'm disappointed and outraged by the many failures at the Memphis VA medical center, particularly the allegations regarding patient safety," Roe said in a statement. "This is unacceptable, plain and simple."

Roe said he has been investigating the hospital since January, and sent investigators to "help uncover instances where the health and well-being of our nation's heroes is being endangered."

Memphis 1 of 4 under close watch by top VA official

There are 168 VA hospitals in the country and U.S. territories.

The other hospitals reporting weekly to the VA's top health official are in Washington, D.C.; Manchester, N.H; and Marion, Ill. An investigation found patients were in “imminent danger” at the VA hospital in Washington earlier this year because of equipment shortages, including critical surgical supplies.

A similar crisis unfolded at the Manchester VA hospital after The Boston Globe reported in July on inadequate care and other shortfalls there, including a fly-infested operating room and canceled surgeries.

In Marion, Ill., a significant decline in patient safety culture and reports of deaths prompted members of Congress earlier this year to demand an investigation.

In Memphis, the VA has quietly removed an array of top managers at the hospital in recent weeks, including the chiefs of surgery, anesthesiology, and research, according to the internal documents, all moves announced by new director David Dunning.

Dunning, a twice-deployed Army veteran, began in May as the first permanent director at the Memphis VA in nearly two years. Since taking over, he has aggressively filled hundreds of vacant positions, an area where he has previously said the hospital has struggled, which has affected some of the services that are offered.

A spokesman for VA Secretary David Shulkin said a top-to-bottom review after Dunning took over revealed problems in surgery, research, nursing, engineering and human resources, and as a result, a number of managers were relieved of their duties.

“In addition, VA is conducting an internal investigation to understand how these problems developed, and hold accountable those responsible,” VA Press Secretary Curt Cashour said.

Cashour said Shulkin, who took over as secretary in February, has made it a priority to quickly identify and address vulnerabilities across the VA hospital system.

“When we determine facilities need extra attention – such as those in Memphis and Marion, Ill. – they are receiving it,” Cashour said. “And we are not hesitating to take swift accountability actions when warranted.”

The Memphis VA declined to comment.

Memphis VA has a history of problems

Mary Davis says she knows first-hand just how bad care can be at the Memphis VA – and how tragic the consequences.

After her husband, Vietnam veteran Charles I. Davis, collapsed on the kitchen floor in their Atoka, Tenn., home in 2015, an MRI scan showed he had a tumor in his neck. She said when she asked doctors to check a scan taken at the VA the previous year, they found the tumor had been visible but VA clinicians had failed to diagnose it.

By the time they caught it, the tumor had damaged his spine and he is now paralyzed.

“They should have caught it,” she told USA TODAY. “I am totally 100 percent disappointed in the care.”

The hospital has faced problems and heightened scrutiny since at least 2011.

Years before a wait-time scandal made national news and spurred the resignation of the VA secretary in 2014, the Office of Inspector General found delays in several areas of the hospital in August 2011.

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At that time, the emergency department was so overcrowded, patients were left on stretchers in hallways awaiting treatment, some for as long as 14 hours and others who left without ever being seen.

According to VA statistics, the hospital is among the worst in the country for patient safety and inpatient outcomes. Death rates following acute care or pneumonia treatment also are among the worst of any of the agency’s medical centers.

“It’s a house of horrors,” said Sean Higgins, a former logistics technician who has been reporting on problems at the hospital and says supervisors retaliated against him for the disclosures.

Just last year, a suspicious brown liquid was found in the clogged floor sink of one of the hospital's rooms, the smell of which drew the attention of the operating room manager and housekeeping director during rounds, who thought there might be human tissue in the liquid.

A pipe fitter employed by the VA was called to unclog the sink, who put the liquid into a bucket, told the safety office and left it outside.

An OSHA investigation revealed the liquid had human parts in it, and was not marked properly as hazardous material. That probe also found the pipe fitter was not treated for potential exposure to Hepatitis B and wasn't trained on how to handle blood-borne pathogens.

In January, Roe said in a letter that he wanted an investigation of the facility after videos surfaced that allegedly showed VA employees abusing veterans.

Earlier this summer, Shulkin highlighted the facility in a White House briefing, where he said a VA employee had been kept on the payroll while serving a 60-day jail sentence for multiple DUI convictions.

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The internal documents also reveal that a surgical tech with a 10-year history at the VA was present at 33 of 47 surgeries by a contracted surgeon in 2016, but had no record of privacy training, background check or drug tests by VA human resources officials. VA employees indicated they knew the assistant was not a VA employee, but were afraid to report it.