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 he ended up with a piece of plastic packaging that VA providers had mistakenly embedded in a critical 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 worst of 168 VA hospitals in the country.

The hospital is one of only four 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 scores only one out of five stars in the agency’s quality-of-care rankings and the documents show reports of threats to patient safety at the hospital soared to more than 1,000 last year, up from 700 the year before.

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Among the other 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.”

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.

The VA quietly removed an array of top managers at the hospital in recent weeks, including the chiefs of surgery, anesthesiology, and research, according to internal documents.

In response to inquiries from USA TODAY, a spokesman for VA Secretary David Shulkin said a new director took over in May and did a top to bottom review of the facility. VA Press Secretary Curt Cashour said the staff changes are the result of that review, which found problems in surgery, research, nursing, engineering and human resources.

He said Shulkin, who took over as secretary in February, has made it a priority to quickly identify and address vulnerabilities across the VA 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 other VA hospitals reporting weekly to the VA's top health official:

• Marion, where significant declines in patient safety culture and reported deaths prompted an investigation earlier this year.

• Washington, D.C., where investigators found surgical shortfalls earlier this year that placed veterans in imminent danger.

• Manchester, N.H., where The Boston Globe revealed dangerous conditions in July, including a fly-infested operating room and canceled surgeries.

They may represent a small sliver of the VA’s 168 hospitals across the country, but the stakes are high for the thousands of veterans reliant on them.

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 diagnosis 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 Memphis VA has faced a seemingly intractable cascade of problems for years.

In 2012, investigators concluded veterans had endured serious treatment delays at the hospital. The emergency department was so overcrowded, patients were left on stretchers in hallways, some for as long as 14 hours and others who left without ever being seen.

A year later, they found delays in processing “urgent laboratory tests” and that patients had died in the emergency room. One received a medication for which the patient had a known drug allergy, another wasn’t monitored after receiving multiple sedating medications, and a third with high blood pressure suffered a bleed in the brain, again after inadequate monitoring.

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In 2014, employees started blowing the whistle on continuing lapses, from neglected medical records to contaminated medical equipment. A video in 2015 purportedly showed an empty nurses’ station in the critical spinal cord wing.

VA officials ousted the hospital’s director amid "underperformance" issues in February 2016, but the problems continued. OSHA, which monitors workplace safety, issued multiple citations to the hospital in May 2016 for improper disposal of human tissue.

A "house of horrors"

“It’s a house of horrors,” said Sean Higgins, a former logistics technician at the hospital.

Then there was the botched surgery in September 2016. An internal report says VA clinicians inserted a catheter into an artery that supplied blood to the veteran’s right foot but could not get it past a narrowed portion of the vessel. They pulled it out and administered medications to try and lessen any blockages.

What they didn’t realize is that they had not removed plastic packaging on the catheter before inserting it. And the packaging stayed in his leg.

An investigation found that after the procedure he had lost complete blood flow through the artery. The amputation came 22 days later.

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Cashour, the VA press secretary, said the agency is continuing to investigate problems discovered in the top-to-bottom review conducted in recent months, including shortfalls in the surgical department.

He said the VA wants to “understand how these problems developed, and hold accountable those responsible.”

Rep. Phil Roe, R-Tenn., chairman of the House Veterans Affairs Committee, said he is "outraged" by the ongoing issues at the Memphis VA. His staff has been investigating the hospital since January, when videos showed two staff members allegedly abusing a patient.

“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."